bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract

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 &gt;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

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

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 &gt;12 years. There is a low (&lt;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

Abstract

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

Abstract

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.