bluuebunny/crossref_metadata_2025 huggingface dataset:
Rare Surgical Lung Biopsy Findings of Metastatic Pulmonary Calcification Associated with Chronic Renal Failure
Authors: Ronen N , Sheinin Y
Published: October 2020

Introduction/Objective

Metastatic pulmonary calcification is a metabolic lung disease characterized by depositions of calcium in lung parenchyma. Depositions of calcium salts are usually caused by hypercalcemia and are associated with end-stage renal disease, primary and secondary hyperparathyroidism, and hemodialysis. It is mostly asymptomatic and clinically silent but can lead to life-threatening respiratory failure.

Methods

We present a case of a 53-year-old woman, with a failed renal transplant and on hemodialysis, admitted with cough and shortness of breath. Computed tomography showed extensive diffuse bilateral groundglass and nodular opacities. Bronchoscopy was unremarkable. BAL results were negative for infection. The initial differential diagnosis included pneumonitis, interstitial lung disease, and chronic obstructive pulmonary disease. VATS lung wedge resection was performed.

Results

Microscopically there were numerous interstitial, peribronchial and perivascular calcifications highlighted by Van Kossa stain. Calcifications were associated with a marked interstitial fibrosis confirmed by trichrome stain. There was no evidence of significant acute and chronic inflammation, granulomas, fibroblastic foci and vasculitis.

Conclusion

Metastatic pulmonary calcification is found in 60–80% of autopsies of patients undergoing dialysis treatment. It is rarely diagnosed during their lifetime, because patients are usually asymptomatic, or the imaging findings are negative. The diagnosis of metastatic pulmonary calcification in our patient prompt further evaluation for repeat kidney transplant and the patient is being considered for parathyroidectomy for her tertiary hyperparathyroidism.
A Rare Case of Dedifferentiated Solitary Fibrous Tumor
Authors: Kanteti A P , Martinez Duarte E
Published: October 2020

Casestudy: Dedifferentiated solitary fibrous tumor is a rare malignant subtype of the common benign mesenchymal neoplasm with fibroblastic differentiation known as solitary fibrous tumor (SFT). These account for less than 2% of all soft masses; and about 20% of SFTs turn aggressive. They feature bland spindle cells creating a classic “pattern-less pattern” in collagenous stroma with prominent staghorn vessels. They can dedifferentiate into a biphasic tumor with low grade areas that are spindle cell rich and high-grade areas with epithelioid cells, mitotic figures and necrosis.

Here we present an 84-year-old female who came from an outside institution for a pathology review. The patient’s clinical history was lacking and biopsies from the right lower and middle lobes of the lung, azygous and hilar lymph nodes were investigated. The pathology revealed multiple areas with epithelioid cells that were pleomorphic and had high nuclear to cytoplasmic ratio. These areas also contained numerous mitotic figures, necrosis and giant cells; with lymphovascular space invasion. There was a clear demarcation between the epithelioid area and an area rich in spindle cells. The spindled areas revealed a fascicular architecture with intervening sclerotic stoma and prominent rounded and dilated blood vessels. Immunohistochemistry analysis of the epithelioid and spindle cell areas were positive for STAT6. Additional testing for CD34 was diffusely positive in the spindle cell component and only focally positive in the high-grade portion of the tumor. Ki-67stain was utilized to estimate the proliferative index which was up to 80 percent in the high-grade epithelioid component and about 15% in the spindle cell portion. These morphological and histochemical findings were consistent with the diagnosis of a dedifferentiated solitary fibrous tumor.
Pulmonary Hamartoma, A Relatively Common Diagnosis with a Rare Presentation
Authors: Sandeep F , Kaur G , Olayinka O , Sieber S , Pathan N
Published: October 2020

Casestudy: Pulmonary hamartomas (PH) are the most common benign tumors of lung, accounting for 75% of all the benign tumors and 8% of all the pulmonary neoplasms. These lung tumors are generally solitary and are observed in middle-aged and older adults with the peak incidence during the sixth decade of life. PH presents as asymptomatic nodule, found incidentally on routine radiographs and CT scans. The majority of PH are located in the lung parenchyma. Endobronchial hamartomas occur much less frequently. An extremely rare presentation of Hamartoma as a mediastinal mass is also reported in the past. The present article reports a case of a 72-year-old female, presented to her primary care physician with the complains of right lower abdominal pain. CT scan of the abdomen and pelvis revealed a partially visualized right paracardiac /mediastinal lipomatous mass. Patient stated that she was informed about a pericardial cyst of about golf ball size, noticed on a routine radiograph 40 years ago. Further workup with CT chest angiography revealed an 8.6 x 5.6 x 5.6 cm mediastinal mass associated with the right heart border and the right cardiophrenic angle, abutting the right diaphragm as well as the medial pleural reflection. A differential diagnosis of teratoma, lipoma/liposarcoma, and hamartoma was considered. Patient underwent robotic assisted surgical resection of the mass which emanated from right lower lung lobe. The histologic features and immunoreactivity pattern were consistent with a benign pulmonary hamartoma. Approximately 90 percent of PH presents as a peripheral intraparenchymal nodule whereas endobronchial hamartoma occurs much less frequently and represents 1.4% - 10 % of PH. A few cases of pulmonary hamartomas presenting as a mediastinal mass have been reported in the past few decades. Here in we report such a case of pulmonary hamartoma presenting as a mediastinal mass.
Basal Ganglia Intracranial Mixed Germ Cell Tumor With Predominance of Yolk Sac Component
Authors: Sameeta F , Liu S , Avalos Hernandez S R , Elkadi O , Herrera G
Published: October 2020

Introduction/Objective

Primary intracranial germ cell tumors (ICGCTs) represent a rare heterogenous group of neoplasms with an overall incidence of 3% of all pediatric brain tumors. ICGCTs are classified into germinomatous and non-germinomatous tumors and approximately 25% are mixed, and contain more than one histologic component. Most ICGCTs are located in suprasellar and pineal regions with some occurring in rare locations such as basal ganglia, thalamus and fourth ventricle.

Methods

In our case, A 9-year-old Asian-American male presented with headaches and a few weeks history of unilateral weakness. Imaging showed a left basal ganglia lesion with midline shift. Serum AFP was elevated at 17,974.5ng/ml.

Results

Histology revealed a biphasic tumor with a predominant yolk-sac component composed of sheets of pleomorphic cells with prominent nucleoli, focally arranged in a reticular pattern with hyaline globules, increased mitoses and foci of necrosis. A lesser component display features of germinoma, in the form of sheets and nests of large cells with clear vacuolated cytoplasm separated by fibrous septa with lymphocytic infiltrates. Tumor cells in yolk sac component were positive for AFP, while PLAP, CD117, D240 stained germinoma component. After receiving 6 courses of chemotherapy and radiation, MRI did not show any evidence of residual disease.

Conclusion

Pathogenesis of ICGCT is thought to be either from primordial germ cells that have migrated aberrantly during embryonic development or from pluripotent embryonic cells that have been entrapped into lateral mesoderm due to misfolding and misplacement and then undergo malignant transformation. The outcomes of ICGCTs differ among histological subtypes. Highest survival rates are seen in patients with germinomas or mature teratomas (10- year survival rate >90% in both groups. The lowest survival rates are seen in choriocarcinoma, embryonal carcinoma and yolk sac tumor.
Fibroadenoma of Ectopic Breast Tissue in the Groin – A Rare Disease Entity
Authors: Emechebe D , Alshal M , Rana T , Agaronov M
Published: October 2020

Introduction/Objective

Ectopic breast tissue (EBT) is a well-documented anomaly of the breast and commonly presents along the embryonic milk line extending between the axilla and groin. Reported incidence of accessory breast is 0.4–6% in females. Pathologies developing in an EBT are reported as a rare entity in the literature.

Carcinoma is reported as the common pathology followed by inflammation and fibroadenoma

Methods

We present a case of 43-year- old female who presented with a painless mass in her right groin for the past year which gradually increased in size. CT abdomen pelvis with contrast showed a 2.2 x 3.0 x 4.4 cm superficial soft tissue mass in the right groin which was suspected to be a lymph node. Further investigation and histopathological report of biopsy showed ectopic breast tissue with admixed chronic inflammation and reactive changes.However, excision of the mass three months later showed showed proloferation of both glandular and stromal elements.

Results

The tissue from the biopsy was positive for GATA 3, mammoglobin, GCDFP and CD 10 and the histological features on excision was confirmatory of fibroadenoma.

Conclusion

In conclusion, when tumors or nodules are found along the mammary line, the presence of breast tissue should be considered during the investigation. It is clinically wise to evaluate and screen carefully cases of supernumerary breast for any pathology and for any associated urogenital anomalies such as supernumerary kidneys, polycystic kidneys and renal cell adenocaricnoma. In our case, patient had no associated urogenital anomalies and she is on follow up.
Multiple Splenic Hamartomas in a Trauma Patient: Report and Literature Review of a Rare Entity
Authors: Khokhar H , Beversdorf W , Jetly R
Published: October 2020

Introduction/Objective

The most common non-hematopoietic primary lesions of the spleen are benign and vascular in nature. Most are encountered incidentally at autopsy, trauma, or by imaging. The histologic differential diagnosis is challenging and often requires the use of immunohistochemical stains to distinguish from other aggressive lesions.

We present a case of multiple splenic hamartomas discovered incidentally in a routine surgical specimen.

Methods

A 46-year-old male trauma patient with no known medical history underwent splenectomy after sustaining a grade 3 splenic laceration.

Results

The specimen weighed 198 grams and featured hemorrhagic capsular disruption. Within the intact parenchyma were multiple non-encapsulated, discrete pale foci ranging in size from 1–9 mm. Microscopically, these corresponded to multiple well-demarcated nodules with tortuous slit-like and dilated vascular channels lined by plump endothelial cells with no significant atypia or mitotic activity, and CD8+/CD31+/CD68+ (focal)/CD21-/CD34- phenotype by immunohistochemical staining. The intervening stroma was disorganized, with abundant foamy histiocytes and scattered lymphocytes with no defined white pulp-like structures. Histopathologic and immunohistochemical findings supported a diagnosis of splenic hamartomas.

Conclusion

Exclusive to the spleen, splenic hamartomas are composed of mixed normal red and white pulp elements in disorganized configuration. They have no known demographic predilection and are exceedingly rare, with one institutional study reporting an incidence of 0.024–0.13% at autopsies. Congenital malformations of red pulp, neoplasms of red pulp, and post-traumatic reactive origin have been discussed as possible etiologies. Although rarely presenting with splenomegaly and hypersplenism, most cases are asymptomatic. Differentiation from other splenic vascular lesions is often challenging, and CD8 positivity in endothelial cells is usually a defining characteristic.

Familiarity with the features of this rare and benign entity is important to distinguish it from malignant primary and metastatic tumors.
“Duodenal Submucosal Glandular Lesion with Brunner and Paneth Cell Differentiation”: A Variant of Pyloric Gland Adenoma? Morphologic and Immunohistochemical Similarities and Differences
Authors: Alawad M , Ilyas G , Xia R , Xie Q , Shin C
Published: October 2020

Introduction/Objective

Duodenal epithelial polyps are reported in up to 3% of patients referred for upper endoscopy. Most include non-neoplastic lesions such as Brunner gland nodule/polyp and pancreatic or gastric heterotopia.

Neoplastic lesions such as pyloric gland adenomas (PGA) are less frequently encountered and have the propensity to progress to adenocarcinoma. Herein we report a duodenal submucosal glandular lesion that has a morphologic resemblance to PGA, but very different in several aspects. We compare and contrast the characteristics of these two lesions.

Methods

This was a 63-year-old man referred for an upper GI endoscopy for complaints of indigestion, dyspepsia, and weight fluctuation. Endoscopy showed a 13 mm polypoid lesion in the second portion of the duodenum, opposite to and separate from the ampulla. An en-bloc hot snare was used to resect the polyp. Histopathologic examination showed features reminiscent of PGA, namely a complex submucosal proliferation of tightly packed variably dilated glands and villous fronds lined by a monolayer of columnar cells with basally located round nuclei and prominent nucleoli. In contrast, however, the columnar cells in most of the lesion contained abundant mucinous cytoplasm resembling Brunner’s glands as well as areas of prominent paneth cell differentiation. The characteristic amphophilic ground glass cytoplasm of PGAs was only noted in a minor component of the lesion. MUC6 and MUC5AC, immunostains that are typically expressed in PGA, were negative. Additionally, p53 showed a wild-type pattern, beta- catenin showed normal membranous staining, and the Ki-67 index was low.

Results

After review of the literature and expert consultation, we were not able to fully classify this lesion under any documented entity, however, we believe that it could be akin to PGA. Authors hypothesized that PGAs may originate from stem cells within Brunner glands as a response to chronic injury. These cells may then differentiate upwards, forming gastric foveolar metaplasia or downwards giving rise to Brunner gland hyperplasia.

Conclusion

Based on this hypothesis, the proliferating cells are prone to mutations resulting in a hyperplasia/metaplasia to dysplasia sequence that leads to the formation of PGAs or lesions such as the one demonstrated here.
The First Case Of The Myopericytomatosis Of The Foot With RAF1 Rearrangement Involving Intron 7 (ATG7-RAF- 1)
Authors: Dehghani A , Alshal M , Doi D , Shvartsbeyn M
Published: October 2020

Introduction/Objective

Myopericytomatosis, recently described by Yin P. Hung et al [1], is an extremely rare myopericytic proliferation with only less than 15 reported cases in the English literature. This neoplasm has been described as dermal or subcutaneous well-circumscribed nodules composed of ovoid to spindled cells in a perivascular distribution, with no significant necrosis, atypia or mitosis. It usually involves the lower extremities with the ankle being the most common location. Next-generation DNA sequencing (NGS) in all the previously reported cases exhibited PDGFRB alterations with no BRAF, NOTCH, and/or GLI1 alterations [1].

Methods

We report a 47-year-old man who presented multiple well-encapsulated nodules on his right foot that were localized to the fascia/subcutaneous fat by MRI; fibromas were the main radiologic differential diagnosis.

Results

The biopsy and subsequent excisional specimens showed diffuse involvement by numerous discrete myopericytomatous nodules composed of bland spindled to ovoid cells. Immunohistochemical staining demonstrated that the myopericytic cells are strongly positive for SMA, focally positive for caldesmon with a patchy cytoplasmic CD99 staining. Ki-67 showed a low proliferation rate of 1–2%. Desmin, CD31, CD34, HHV8, STAT6, S100, HMB45, and Melan-A immunostains were negative. The diagnosis of myopericytomatosis was made. The NGS revealed that the tumor cells are positive for RAF1 rearrangement involving intron 7 (ATG7-RAF-1) with no other findings, including PDGFRB alterations.

Conclusion

Myopericytomatosis is an exceedingly rare entity with most of the previously reported cases involving the lower extremities and only two cases involving the foot. In all the prior cases, the PDGFRB mutation N666K was noted [1]. We report the first case of RAF1 rearrangement in myopericytomatosis of the foot with no other genetic alterations.
Proximal Type - Epithelioid Sarcoma- A Rare And Aggressive Soft Tissue Neoplasm
Authors: Zaheer S , Xu K , Shakil F
Published: October 2020

Introduction/Objective

Epithelioid Sarcoma is a rare malignant soft tissue neoplasm that is well known for local recurrence, regional lymph node involvement, and metastasis. It accounts for less than one percent of all sarcomas. Two subtypes of epithelioid sarcoma are described: the conventional or classic subtype and the proximal subtype, with the classic type being more common than the proximal type. We present a case of proximal epithelioid sarcoma involving the inguinal region, in which the patient presented with the history of weight loss for one year and a slow- growing inguinal mass for the last few months. The biopsy was done in an outside hospital and showed carcinoma of unknown origin. Imaging also failed to reveal any clear source of this mass.

Methods

The mass was resected and sent to pathology, where H&E staining and immunohistochemistry was done for diagnosis.

Results

The H&E sections of the left inguinal mass showed proliferation of large epithelioid cells with a moderate amount of cytoplasm, vesicular nuclear chromatin and prominent nucleoli. Mitosis was also seen. Necrosis was not identified. Immunohistochemical staining was done and revealed that the tumor cells were immunoreactive for epithelial marker cytokeratin AE1/AE3 and showed loss of INI-1. Tumor cells were also negative for Myogenin, ERG, HMB-45, MART-1, Myo-D1, S100, and SMA. Considering the cytomorphology and immunophenotypic findings the diagnosis of epithelioid sarcoma, proximal type was made.

Conclusion

Epithelioid sarcoma is a malignant mesenchymal neoplasm with epithelioid cytomorphology and phenotype. Among the two types of epithelioid sarcoma, the proximal type is reported about 50% less than the classic type and is associated with aggressive behavior and worse prognosis. The classic cytomorphology and immunohistochemistry findings helped us in making the diagnosis in this case.
CDX2 Expression in Primary and Metastatic Prostatic Adenocarcinoma: A Retrospective Study
Authors: Girardo` C , Fakhri` N , Khokhar H , Jetly R , Bhalla R
Published: October 2020

Introduction/Objective

CDX2 encodes a transcription factor expressed in the nuclei of intestinal epithelial cells. The CDX2 immunohistochemical stain has excellent diagnostic utility in the setting of carcinoma of unknown primary, especially in combination with cytokeratins 7 and 20. While the stain is fairly specific for intestinal origin, it is also expressed in tumors of other origins. Only rare case reports have described positivity for CDX2 in metastatic prostatic adenocarcinoma. Having experienced a diagnostic dilemma involving CDX2 positivity in metastatic prostate cancer, we decided to study the rate of positivity for CDX2 in primary and metastatic prostate carcinomas. A literature search revealed several immunoassay studies and case reports of CDX2 positivity in the primary and metastatic setting.

Methods

Following IRB approval, a search of the electronic medical records was performed to identify prostatic adenocarcinoma diagnoses on prostatectomy and metastatic specimens. Formalin-fixed, paraffin embedded blocks were obtained. Unstained slides were cut at 4µm and the staining protocol for CDX2 from Cell Marque™ was performed. 109 cases were stained, including 88 prostatectomy and 21 metastatic specimens.

Results

Of the 109 cases, 75 were negative for CDX2, including 19 of the 21 metastatic cases. Of the remaining 34 cases, 10 were strongly positive for CDX2, including two metastatic cases (clavicle and right iliac bone). The remaining 24 were identified as weakly positive (12 cases), focally positive (7 cases), weakly and focally positive (3 cases), or patchy positive (2 cases). Overall, 36.36% of prostatectomy specimens had tumors with some CDX2 positivity, compared to 9.52% of metastatic cases. The patient ages at diagnosis ranged from 44 to 84 years, with a median value of 59 years, and at metastasis ranged from 51 to 87 years, with a median age of 64. PSA ranged from 2.8 to 3564 at diagnosis (median 9) and undetectable to 2024 at metastasis (median 56).

Conclusion

CDX2 is often positive to some degree in both benign and malignant prostates, and can present a diagnostic pitfall in the case of metastasis. Hence, CDX2 positivity does not exclude the diagnosis of prostate cancer in the evaluation of unknown primary. In our study, the number of metastatic cases studied was relatively low. Future studies with more cases could better quantify the positive rate for CDX2 in metastatic prostate adenocarcinoma.
Duodenal-Type Follicular Lymphoma: A Newly Recognized Entity in the 2016 World Health Organization Classification Update
Authors: Rajack F , Taddasse-Heath L , Naab T J
Published: October 2020

Introduction/Objective

Most cases of primary follicular lymphoma (FL) in the gastrointestinal tract occur in the second part of the duodenum, presenting with multiple small polyps. Duodenal type follicular lymphoma (D-FL) is a newly recognized entity in the 2016 WHO classification update.

Methods

Upper endoscopy in a 72 year old female with iron deficiency anemia revealed a single 8 mm sessile polyp with no bleeding in the duodenal bulb. Histology revealed dense infiltrate of small mature lymphocytes with a nodular growth pattern. Follicles, composed predominantly of centrocytes with scattered centroblasts, diffusely expressed CD20, CD10 and BCL-2.

Results

This immunoprofile characterizes follicular lymphoma. Real-time polymerase chain restriction assay detected BCL-2 MBR/JH DNA fusion sequence, usually resulting from t(14;18)(q32;q21) translocation and confirming D-FL. D- FL is often asymptomatic, discovered incidentally at endoscopy. It is usually low grade (grade 1–2), presenting at low stage, with immunophenotype and t(14;18)(q32;q21) similar to other FLs. However, in comparison to nodal FL, D-FL has higher selective use of V4 and V5 immunoglobulin heavy chain gene rearrangements, which has been linked to antigen dependent mechanisms in lymphoma development; this feature is shared with Mucosa-Associated Lymphoid Tissue (MALT) lymphoma.

Conclusion

D-FL often remains localized to the small bowel and has a good outcome even with local small bowel recurrences. It has a long term survival of >12 years. There is a low (<10%) risk of progression to nodal disease and given the indolent clinical course, a watch-and-wait approach is reasonable for most patients.
Identification of Lupus Podocytopathy with Coexistent Glomerular Diseases – A Case Report
Authors: Ding L , Tomaszewski J , Liu L , Murray B
Published: October 2020

Introduction/Objective

Lupus podocytopathy (LP), featured by nephrotic syndrome, is a unique subtype of lupus nephritis that mimics minimal change disease or primary focal segmental glomerulosclerosis (FSGS) on renal biopsy with diffuse podocyte foot process effacement and no capillary-loop immune deposits. LP usually presents on a background of ISN/RPS class I or class II lupus nephritis, and very rarely may present without immune deposits.

Diagnosis of LP, when confounded by other glomerular diseases associated with nephrotic syndrome, can be very challenging and requires thorough clinical and pathology correlations.

Methods

Here we report a case of LP in a patient with nephrotic syndrome and multiple comorbidities affecting kidneys. A 24-year-old female with type-I diabetes, psoriasis, and intermittent arthritis/rash of unknown etiology, presented with abrupt onset of nephrotic proteinuria attributed to recent low dose prednisone therapy, and renal insufficiency. A renal biopsy showed nodular glomerulosclerosis and FSGS. No immune deposits were identified by immunofluorescence or electron microscopy. Ultrastructurally there was also diffuse glomerular basement membrane thickening and over 90% podocyte foot process effacement. With no established systemic lupus erythematosus (SLE), the case was initially diagnosed as diabetic nephropathy with coexistent FSGS as the etiologies for nephrotic proteinuria, and the patient was put on ACEI and diuretics. However, massive proteinuria persisted, and the patient also developed pancytopenia. Serology concurrent with the biopsy came out later showing positive autoantibodies against dsDNA, Smith, and Histone. With continued worsening of creatinine, a renal biopsy was repeated revealing essentially similar findings to the first biopsy.

Results

Integrating the serology results and clinical presentation, SLE was favored. The pathology findings were re- evaluated and considered to be most consistent with LP and coexistent diabetic nephropathy, with FSGS either a component of LP or an independent lesion secondary to diabetes or hypertension. The patient was started with high dose prednisone at 60 mg/day. One month later, her proteinuria, serum creatinine, pancytopenia, skin rash, and arthritis were all significantly improved.

Conclusion

LP can be easily masked by coexistent glomerular diseases. Sufficient awareness of the entity is necessary for the appropriate diagnosis and treatment.
Morphologic and Immunohistochemical Analysis of Mesenteric and Retroperitoneal Mucinous Cystic Neoplasms
Authors: Van Treeck B J , Horton R , Graham R P , Pai R , Rosty C
Published: October 2020

Introduction/Objective

Mucinous cystic neoplasms (MCN) are neoplasms with mucinous epithelium surrounded by ovarian-type stroma, occurring in the pancreas and liver. Reports of MCN arising outside the liver and pancreas are rare. We aim to perform a clinicopathologic, morphologic and immunohistochemical analysis of mesenteric and retroperitoneal MCN arising separate from the pancreas and liver.

Methods

Seven mesenteric or retroperitoneal MCN (n=7) were identified and clinical and radiologic information obtained, where available. The following immunostains were performed on each case: keratin 7, keratin 19, estrogen receptor, progesterone receptor, calretinin, inhibin-α, and SF-1.

Results

All seven MCN were from women with a median age of 41 years (range: 28-70 years). The median size of the MCN was 8cm (range: 8-14.5 cm) involving the retroperitoneum (n=5) and mesoappendix (n=2). One patient was diagnosed with a synchronous right ovarian mucinous cystadenoma. Morphologically, all MCN displayed mucinous or mixed non-mucinous-mucinous cuboidal to columnar epithelium without dysplasia. Ovarian-type stroma was identified underlying the epithelium with foci of luteinized stromal cells. The ovarian-type stroma expressed estrogen and progesterone receptors in all seven cases, two cases stained with SF-1 showed diffuse strong stromal positivity, and one case stained with inhibin showed focal strong stromal positivity. Additional immunohistochemical analysis with CK7, CK19, calretinin, inhibin-α, and SF-1 on all cases is pending.

Conclusion

Clinicopathologic, morphologic, and immunohistochemical characteristics of mesenteric/retroperitoneal MCN are similar to their pancreas and liver counterparts. Familiarity with this entity and knowing it can arise in mesenteric/retroperitoneal locations is important for accurate diagnosis and to distinguish it from mucinous carcinoma, teratoma, endometriosis and other differential diagnoses which have different implications. We propose that mesenteric/retroperitoneal MCN may possibly arise from primordial germ cells that underwent aberrant migration during their retroperitoneal descent through the fetal dorsal mesentery which gives rise to the neck and body of the pancreas as well as the mesentery and mesoappendix.
Esophageal Pityriasis Lichenoides Chronica
Authors: Dasaraju S , Liu S , Elkadi O
Published: October 2020

Casestudy: Pityriasis Lichenoides is an uncommon inflammatory skin condition of unknown cause that ranges from mild chronic form to a more severe acute eruption. The mild form, pityriasis lichenoid chronica (PLC), is characterized by the gradual development of symptomless, small scaling papules that spontaneously flatten and regress over weeks. The acute form is characterized by the sudden eruption of small scaling papules that develops into blisters and crusted red brown spots. This acute form is called pityriasis lichenoides et varioliformis acuta (PLEVA). Both forms usually involve the skin of the trunk and proximal extremities. Visceral involvement is not a well described phenomenon. We report a case of a 69-year-old female with significant history of PLC controlled by immunosuppressive therapy. The patient presented with odynophagia and dysphagia that occurred after a period of discontinuation of her PLC treatment. She underwent endoscopy which showed distal esophageal narrowing and stricture. Biopsy revealed squamous esophageal mucosa with marked intraepithelial lymphocytosis along with basal cell hyperplasia, acanthosis, vacuolation and prominent apoptosis in the epithelial cells. PAS, CMV and HSV stains showed no fungal or viral organisms. The esophagus is commonly involved in a number of dermatologic conditions including pemphigus vulgaris, erythema multiforme, epidermolysis bullosa, lichen planus and lichen sclerosis. The pattern of involvement is often in the form of “lymphocytic esophagitis”. To our knowledge, there are no reported cases in the literature on PLC involving the esophagus. While the diagnosis heavily relies on clinical history of PLC, awareness of potential involvement of the esophagus and attention to certain endoscopic and morphological details may better help classify esophagitis biopsies.
A Case Of Pancreatic Hamartoma Mimicking Malignancy: An Uncommon Pitfall
Authors: Dasaraju S , Liu S , Kelly R , Mneimneh W
Published: October 2020

Casestudy

Hamartomas are benign, disordered, tumor-like growth of cellular constituents resembling the tissue of its origin. Hamartomas are usually seen in lung, heart, kidney and spleen. Pancreatic hamartomas (PH) are extremely rare, accounting for <1% of all hamartomas. PH occurs at any age (median: 50 years) without gender predilection. PH presents as single or multiple, solid and/or cystic mass composed of exocrine tissues. Admixed neuroendocrine cells may be seen, but well-formed islets are unusual. PH stroma is typically positive for CD34 by immunohistochemistry. We present a case of a PH resected for the clinical suspicion of malignancy, with the final diagnosis established postoperatively.

The case is that of a 74-year-old male with an incidental 2.3 x 1.7 x 1.1 cm hyperenhancing solid mass of the pancreatic uncinate process, found during anemia workup. The radiologic appearance was suspicious for a neuroendocrine tumor. Biopsy of the mass showed benign-appearing pancreatic ductal and acinar tissue. Given the clinical suspicion of malignancy, the patient elected to undergo a pancreaticoduodenectomy. Macroscopically the mass was well-circumscribed with solid, tan-white, firm cut surface. Microscopic examination revealed well- circumscribed proliferation of disorderly-arranged, well-differentiated, bland exocrine pancreatic tissue. Chromogranin, synaptophysin and CD56 immunostains did not highlight significant neuroendocrine component. Ki-67 proliferation index was low (1%). CD34 and CD117 immunostains were negative in the stroma. The findings were consistent with PH.

Conclusion

PH may mimic a malignant process of the pancreas. The preoperative diagnosis of PH is extremely challenging due to the lack of characteristic clinical and radiological features, therefore, the diagnosis of PH is often made on resection specimen. CD34 immunostain is not always helpful for the diagnosis as it may be negative in PH stroma. Although extremely rare, pancreatic hamartoma should be considered in the differential diagnosis of a pancreatic tumor.
Acquired Cystic Disease-Associated Renal Cell Carcinoma: An Unusual Case in the Absence of Acquired Cystic Disease or Dialysis
Authors: Pandiri M , Freeman J
Published: October 2020

Casestudy: Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a relatively recently recognized subtype of RCC. Although much less common than clear cell RCC and papillary RCC, it is the most common tumor occurring in patients with end-stage renal disease (ESRD) and acquired cystic disease (ACD). The tumor is said to occur exclusively in patients with acquired cystic disease, most commonly in patients undergoing long- term dialysis. We report a case of a 67-year-old male with stage IV chronic kidney disease due to membranous glomerulonephritis for 6 years with no history of dialysis and without a history of acquired cystic disease. The patient presented with left lower quadrant pain. On imaging, an enhancing exophytic mass was noted in the left kidney. Partial nephrectomy was performed, demonstrating a unifocal 2.2 cm nodular mass diagnosed as ACD-RCC.

Microscopically, the tumor revealed intracystic papillary growth, focal cytoplasmic vacuoles (sieve-like growth) with involvement of perinephric adipose tissue by the tumoral cysts. Immunohistochemical staining revealed tumor cells positive for CD10, MIT/113, MPAX8, AMACR, and negative for CK7 and CD117. This immunophenotype supports the diagnosis of ACD-RCC (although itis not specific). Although the patient lacks a clinical history of dialysis and no intratumoral oxalate crystals were noted, the morphological findings and immunohistochemistry support the diagnosis of ACD-RCC, with concurrence by outside expert opinion. In summary, we present this unusual case of ACD-RCC to emphasize the awareness of this entity when considering the differential diagnosis of RCC in adult patients with chronic kidney disease, and specifically distinguish it from the close differential of papillary renal cell carcinoma.
Epithelioid Variant of Angiosarcoma Associated with an Arteriovenous Fistula in the Setting of Post-Renal Transplant
Authors: Harrell M , Broehm C J
Published: October 2020

Introduction/Objective

Angiosarcomas are rare malignant tumors that mimic the function and morphologic features of endothelium. They are commonly associated with prior radiation exposure, but have rarely been reported arising in synthetic graft material, congenital syndromes, or in the vicinity of an ateriovenous fistula (AVF). Herein, we report the clinical and histologic features of an epithelioid angiosarcoma arising in an AFV in the setting of post-renal transplant.

Methods

A 67-year-old Native American man with a cadaveric kidney transplant twelve years earlier for end-stage renal disease presented with pain at the site of his wrist AVF. The initial clinical impression was of a thrombosed fistula, and a routine AVF revision was performed. Histologic sections demonstrated an infiltrative neoplasm comprised of round, moderately pleomorphic, epithelioid cells with centrally located nuclei and prominent nucleoli, which was associated with a large thrombosed vessel. By immunohistochemistry the neoplastic cells expressed CD31 and ERG, with patchy reactivity for CD34, pan-cytokeratin, and SMA. Desmin, caldesmon, calponin, EMA, and SOX10 were negative. INI-1 was retained. A re-excision was necessary for complete margination of the lesion, and demonstrated similar histologic findings to the initial specimen.

Conclusion

Angiosarcoma specimens in which epithelioid appearing cells predominate are classified as epithelioid angiosarcomas, a highly aggressive variant that conveys a comparatively worse prognosis than their non-epithelioid counterparts. These classically are positive for CD31, Fli-1, Factor VIII and vimentin, with variable staining for EMA, cytokeratins, and CD34. Epithelioid angiosarcoma arising from an AVF is a rare entity, with less than 30 cases reported in the literature. The diagnosis should be considered in patients presenting with an enlarging mass, pain, or bruising near a previously quiescent AVF site. Given the aggressive nature of this disease process, there may be consideration for routine submission of AVF revision specimens for histologic evaluation.
Pulmonary Cement Emboli After Kyphoplasty: A Case Of Bilateral Pulmonary Emboli And Exacerbation Of Interstitial Lung Disease
Authors: Balikani L , Chen F
Published: October 2020

Introduction/Objective

Osteoporosis often complicates the management of vertebral conditions, including spinal stenosis and vertebral fractures in the geriatric population. In addition to pharmacologic pain management; surgical interventions are employed if the pain is not adequately managed. The surgical interventions include vertebroplasty and kyphoplasty. These procedures involve the introduction of a cement polymer, Polymethylmethacrylate (PMMA), into the vertebral body. Cement leakage is a reported complication more commonly seen in vertebroplasty (30-75%) compared to kyphoplasty (8-33%). This occurs due to distant leakage of cement into the venous plexus or retrograde migration into the aorta which leads to pulmonary cement emboli (PCE). PCE are usually asymptomatic; few patients are symptomatic; seen in 0.9% for vertebroplasty and 0.4% for kyphoplasty. PMMA has a prothrombotic effect, contributing to the thrombosis of the pulmonary vessels. Symptoms typically arise weeks to months after the procedure. In addition, it has been reported that rarely PCE can present with ARDS especially in patients with interstitial lung abnormalities.

Methods

We present a case of an 80-year-old female with a history of hypertension, diabetes mellitus and osteoporosis who underwent a kyphoplasty procedure with use of PMMA for spinal stenosis. Her post-operative course was complicated by multiple surgical revisions. She was noted to have pulmonary cement emboli five months post kyphoplasty and developed significant shortness of breath eight months post procedure. She ultimately developed cardio-pulmonary failure and was found to have bilateral pulmonary emboli and cement emboli at autopsy. Microscopic examination of the cement emboli documented round to oval vacuole-like cavities within and around blood vessels consistent with PMMA.

Conclusion

The histo-pathologic findings of cement emboli are not well documented in human beings compared to animal models. We attempt to highlight the gross and microscopic findings of PMMA cement emboli which is essential in the clinical-histo-pathologic correlation and characterization of pulmonary emboli at autopsy.
Dediduosis: An Incidental Autopsy Finding Simulating Metastatic Disease
Authors: Quereda Bernabeu B , Strayer D
Published: October 2020

Casestudy

Deciduosis, defined as the presence of benign decidual cell clusters outside the endometrium, is an uncommonly reported entity described in pregnant women. It represents progesterone-induced metaplasia of stromal cells, and has been reported in ovary, cervix, uterine serosa and fallopian tubes. Deciduosis has been noted very rarely in peritoneum, omentum, appendix, diaphragm, abdominal organs and pelvic lymph nodes. As an incidental finding, it must be distinguished from more ominous entities which it may resemble.

Methods

A 30 year old female, 29w pregnant, died from an intracranial hemorrhage. Her history was significant for Crohn’s disease and multiple sclerosis, with no previous history of malignancy. At the time of autopsy, she had had an emergency C-section and delivered a healthy male newborn. She donated multiple organs which limited our examination. However, we examined her gynecologic and aerodigestive tract completely. Several enlarged abdominal lymph nodes were identified and sampled for histologic examination.

Results

Gross examination of the gynecologic tract was consistent with status post cesarean section, with no other significant findings. Microscopically, one abdominal lymph node showed multiple clusters of cells with abundant amphophilic cytoplasm, small round nuclei, inconspicuous nucleoli, and prominent myxoid change, obliterating the sinusoids. Similar cells were found in subserosal locations in both ovaries, the endocervical stroma and the mesoappendix. The cells were negative for cytokeratins and calretinin, ruling out metastatic carcinoma and mesothelioma, respectively. CD68 highlighted individual sinusoidal macrophages surrounding the clusters. The cells were positive for vimentin, CD10, and progesterone receptor. These findings are consistent with deciduosis. The absence of associated endometrial-type glands excluded a diagnosis of endometriosis with decidualized endometrial stroma.

Conclusion

Deciduosis is a rarely reported entity that is important to recognize when dealing with suspicious cell clusters simulating metastatic disease in a pregnant woman. There are few high quality photomicrographs in medical literature, particularly for unusual locations such as lymph nodes. We believe our findings will help illustrate the morphologic appearance and immunohistochemical characteristics of this entity, and help distinguish it from more serious diseases.
Primary Cutaneous Follicle Center Lymphoma (PCFCL) with Parotid Gland Involvement
Authors: Ayub S , Al-Duwal Z , Sellers D , Rosenberg A
Published: October 2020

Introduction/Objective

Primary cutaneous follicle center lymphoma (PCFCL) is the most common primary cutaneous B-cell lymphoma. It arises from mature germinal center B lymphocytes. Here we report two cases of PCFCL with parotid gland involvement.

Methods

First case is a 66-year-old male with an enlarging forehead mass for nine months and a painless nodule on the right pre-auricular skin. Second is a 39-year-old male with a history of a recurring scalp spindle cell B-cell lymphoma now presenting with an enlarging lesion on the scalp and “fullness” in the right neck. There was no nodal or other extranodal involvement found in either case. Skin and parotid gland biopsies were obtained in both cases.

Results

Case one: The skin and parotid gland demonstrated sheets of predominantly medium sized infiltrating lymphoma cells, positive for CD20, Bcl-6, CD5 (dim) and Bcl-2 (dim), and negative for CD10, Bcl-1, and MUM-1. The epidermis was spared.

Case two demonstrated medium sized, spindle shaped lymphoma cells. The skin showed a vague follicular growth pattern, sparing the epidermis. The parotid gland showed diffuse infiltration by lymphoma cells, positive for CD20 and Bcl-6, Bcl-2 (dim) and no definite positivity for CD10.

Fluorescent in situ hybridization for t(14;18) translocation was absent in both cases.

Conclusion

Dissemination of PCFCL to extracutaneous sites is uncommon (~10% of cases) and to our knowledge, has not been reported in the parotid gland. Here we present two unique cases, which in the absence of nodal disease, prove the diagnosis of PCFCL with parotid gland involvement.
When Patients Have Neuropathy: Frequency Of A Positive Immunofixation Electrophoresis (IFE) For Monoclonal Protein When The Serum Protein Electrophoresis (SPEP) Is Negative, The Veteran Affairs Medical Center (VAMC) Experience
Authors: Petersen J M , Litman M , Millili R , Jhala D
Published: October 2020

Introduction/Objective

Although serum protein electrophoresis (SPEP) is the backbone of testing to determine the presence of monoclonal proteins, immunofixation electrophoresis (IFE) is more sensitive with the ability to pick up fainter bands or bands comigrating with the normal beta protein peak. Given the costs of performing additional IFE and the known increased sensitivity, algorithms for reflex IFE published in the literature have stated that unexplained neuropathy would be an indication for reflex IFE even if the SPEP appears negative in a new patient. However, literature on exactly how many of these reflex IFE’s end up positive is sparse. Therefore, we present the Veteran Affairs Medical Center (VAMC) experience in a veteran population.

Methods

As part of a quality assurance/improvement project, retrospective Vista/Fileman search of all SPEPs with IFE performed from January 2017 to February 2019 was undertaken to identify all SPEPs/IFE with the standard comment language typically used in patients with neuropathy, namely a preliminary diagnosis of no monoclonal bands on SPEP with an IFE to confirm this diagnosis. All SPEPs and IFEs had undergone review by a pathologist prior to signout which includes a chart review in the computerized patient record system (CPRS) to rule out the documented presence of unexplained neuropathy in new patients who have not previously had IFE workup.

Results

There were 129 SPEP/IFE cases identified. Of these 129, the overwhelming majority or 123 specimens (95%) were negative on IFE. However, there were 6 specimens (5%) that demonstrated a band on IFE without a band being identified on the SPEP. These bands were in the beta region or very faintly located in the gamma region at or below the limit of detection of the SPEP

Conclusion

The performance of IFE for patients with unexplained neuropathy would, in the veteran population at the VAMC, identify a monoclonal band in about 1/20 cases. This provides support for the published algorithms advocating for performing IFE on negative SPEP specimens from patients with unexplained neuropathy, as this finding might be important and would otherwise have been missed if just the SPEP was performed alone.
Elevated Cardiac Troponin in the Setting of Periodic Symptomatology: A Case Report
Authors: Rohr J M , Pirruccello S , Sofronescu A
Published: October 2020

Introduction/Objective

Serial cardiac troponin measurement is a sensitive method to identify recent cardiac injury and is a necessary function of the clinical chemistry laboratory. We present a case of out-of-range cardiac troponin I (cTnI) elevation which remained spuriously elevated for at least 30 days.

Methods

Cardiac troponins were measured on a DxI (Beckman Coulter), Vitros 5600 (Ortho Clinical Diagnostics), iSTAT (Abbott), and Cobas e602 (Roche) according to the manufacturers’ instructions with appropriate controls.

Heterophile antibody blocking (Scantibodies Laboratories) was performed according to the package insert.

Results

A 58-year-old male with a medical history significant for chronic non-ischemic cardiomyopathy with open valvular repair (ejection fraction 15-20%), chronic atrial fibrillation, and Hodgkin’s lymphoma in remission presented to a rural clinic with chest pain and a cTnI of 0.8 ng/mL (reference <0.04 ng/mL). He was transferred to our tertiary center for open revision. The patient’s cTnI (measured on a Beckman Coulter DxI) was above linearity threshold (>71.00 ng/mL) starting day 1 after surgery. The patient self-discharged against medical advice on day 16. On day 21 he experienced new chest pain and dyspnea and was readmitted with a cardiac troponin T (cTnT) of >35 ng/mL (iSTAT; reference <0.08 ng/mL) and cTnI again above threshold. This value remained elevated for the next five days despite abated symptoms. To address the discordant laboratory and physical findings, dilutional cTnI measurements on serum from day 30 demonstrated linearity. Heterophile antibody testing was negative. cTnI on the DxI machine remained >71.00 ng/mL but was separately measured as 3.4 ng/mL (Vitros 5600, reference <0.08 ng/mL). cTnT was found to be 1.05 ng/mL (Cobas e602; reference 0.00 ng/mL). Comparative examination of all methodologies was unrevealing.

Conclusion

This case demonstrates a spurious elevation of cardiac troponins which remarkably demonstrated linearity on serial dilution. Multiple testing methodologies were necessary to prove fallacy. The cause of the result remains unclear. The clinical pathologist should be aware of possible false positives and investigate unlikely continuous cardiac troponin elevations.