bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extra-nodal Rosai-Dorfman Disease Confined to Breast
Authors: Ozluk E , Shackelford R 
Published: October 2020

Abstract

Introduction/Objective
First described by Rosai and Dorfman in 1969, Rosai-Dorfman Disease (RDD) is an uncommon, idiopathic, reactive lymph node process with an unknown etiology. It may involve extra-nodal organs including the skin, bone, soft tissue, and eyes. However, breast involvement is rare and RDD confined to breast without nodal involvement is extremely uncommon.

Methods
Here we present a case of RDD confined to breast. The patient was a 51-year-old African American woman who was found to have an irregular, solid left breast mass on routine mammogram, which had speculated irregular margins and measured of 37.0 x 32.0 x 32.0 mm. She did not have any symptoms, nor any palpable lymph nodes.
The clinician stated that the lesion was highly suspicious for a breast malignancy and requested a fine needle aspiration (FNA) of the mass, followed by total excision.

Results
An FNA was interpreted as atypical histiocytic cells in a mixed lymphoid background. Histopathologic examination revealed an ill-defined mass with sheets of histiocytes, plasma cells, and a mixed lymphocytic population, with occasional germinal centers. Some of the histiocytes were spindle shaped and associated with storiform collagen deposition. The histiocytes had single and multiple nuclei and exhibited occasional emperipolesis.
Immunohistochemical staining with S100 diffusely highlighted the histiocytes, whereas CD1a was negative. CD3 and CD20 immunostains were positive for mixed-type lymphocytic infiltration. Cytokeratin staining was performed and reassuringly stained only the benign ductal cells. A diagnosis of RDD of the breast was made, based on these histopathologic findings.

Conclusion
We report an example of an extra-nodal RDD involving the mammary gland that was initially suspected to be breast carcinoma. RDD may still be a diagnostic challenge, especially in a patient with suspected carcinoma. It is the pathologist’s role to lead the clinician to the proper diagnosis and render a correct histopathologic diagnosis.
Pediatric Pancreatic Teratoma: A Rare Case Report
Authors: Sameeta F , Anderson S A , Manci E , Haque M 
Published: October 2020

Abstract

Introduction/Objective
Teratomas are germ cell neoplasms arising from three germinal layers. They are classified as mature or immature. Mature cystic teratomas (MCTs), also known as dermoid cysts, are benign lesions. Common locations include the sacrococcygeal region, ovaries, testes, brain, mediastinumand retroperitoneum. MCT is extraordinarily rare in the pediatric pancreas; only 11 such cases have been reported in the English literature.

Methods
This eleven-month-old female presented for evaluation of two cystic masses in the body and tail of the pancreas. These masses were initially imaged as anechoic cysts in utero by ultrasound at 19 weeks gestational age and followed carefully over the interval. Her past medical history included a left upper lobectomy for congenital lobar emphysema. The pancreatic cysts were excised by laparoscopy.

Results
Grossly, the two tan-pink cysts measured 2.5 cm and 3.1 cm in greatest dimensions, had smooth inner linings and contained clear fluid. Microscopically, the cyst linings included low cuboidal, columnar, ciliated pseudostratified columnar respiratory or fundal gastric epithelia with underlying serous/mucous glands and smooth muscle. These findings were diagnosed as MCT.
Typically, MCT of pancreas have nonspecific clinical presentations, serum markers and imaging; all depending on the tissue types present; so, the diagnosis is primarily made postoperatively by pathological evaluation. Previously reported cases presented as single cysts, ranged 4 months to 16 years in age and measured 8 to 18 cm in greatest dimension. Complete surgical excision and careful follow-upare the mainstay of therapy

Conclusion
Pediatric pancreatic MCTs are extraordinarily rare, so the preoperative diagnosis and treatment is difficult. This case of MCT is the first reported multicystic presentation, the first documented fetal imaging and the smallest size in the English literature. This report shows that MCT must be considered in the differential diagnoses of fetal abdominal cysts and in multicystic pediatric pancreatic masses.
Apply Molecular Method To Diagnosis A Very Rare Bone Primary Myoepithelial Tumor: A Case Report
Authors: Chen F , Syed H 
Published: October 2020

Abstract

Introduction/Objective
A 38-year-old female without a history of trauma and malignancy presented with left knee pain and swelling for two weeks. MRI and PET scan find a left knee mass arising from the bone along the medial metaphysis of the distal femur. She underwent femur resection, and the specimen was sent for pathology evaluation.

Methods
Grossly, the cut surface of the sample revealed a 4.5 x 2 cm area of hemorrhagic softening of the bone with adjacent soft tissue nodules. Microscopically, the tumor showed biphasic or multiphase morphologic features, prominently presented with areas showing well-differentiated epithelial features and other areas with spindling and sheets of tumor cells. Areas suspicious for a vascular invasion were seen at the periphery of the soft tissue extension of the tumor. Immunohistochemistry stains showed the tumor cells are positive for vimentin, AE1/3, EMA, CK7, CK19, GATA3, and BRST2; and are negative for S100, HMB45, GFAP, Calponin, CDX2, PAX8, WT1, P63, CD34, and ER. The molecular test showed positive for the ESWR1 gene but negative for SYT gene translocation.

Results
A diagnosis of primary myoepithelial carcinoma of bone extension into surrounding soft tissue was made.

Conclusion
The most challenging differential diagnosis for this case is metastatic breast cancer. Many of the positive epithelial stains distinctly highlight the epithelial featured geographic areas sparing the background spindled stroma. The positive staining of GATA3 and BRST2, two commonly used breast linage markers, is unusual and not known in myoepithelial carcinoma. In light of the EWSR1 positive and SYT FISH negative results, combined with the morphologic features, locations as well as negative PET scan against its breast origins. Although many myoepithelial markers, such as S100, Calponin, P63, and GFAP were negative, make this case very unique. The molecular diagnosis is the mainstay for this final diagnosis.
Leiomyosarcoma of Urinary Bladder, A Review of Two Cases
Authors: Fakhri N , Bhalla R 
Published: October 2020

Abstract

Introduction/Objective
Leiomyosarcomas of the urinary bladder are rare smooth muscle tumor, and constitute 1% of all bladder malignancies. Although rare, leiomyosarcoma is a clinically significant disease, presenting as a high-grade advanced malignancy with associated substantial morbidity and mortality, if not treated early. The diagnosis can be delayed because of the asymptomatic presentation until the tumor reaches an advanced stage.

Methods
We present two cases of leiomyosarcoma of the urinary bladder. First case: a 63 years old female with a history of cervical carcinoma treated with radiation, 25 years ago, followed by uncomplicated clinical course, until recent development of vesicovaginal fistula. During her work up with cystoscopy, a large bladder mass was identified. Second case: a 71 years old female with a history of treated breast cancer, who presented with recurrent history of cystitis and hematuria. Cystoscopy revealed a nodular mass in the right posterior bladder wall.

Results
Microscopically, both lesions were highly cellular with infiltrative, interlacing fascicles of spindle cells and associated mitosis, cellular atypia and necrosis. Immunohistochemistry revealed positive expression of muscle- specific actin, desmin, and caldesmon; with negative expression of ALK-1, EMA, Cytokeratins and GATA3, in both the cases. Other spindle cell lesions including, leiomyoma, inflammatory myofibroblastic tumor and sarcomatoid carcinoma were included in the differential diagnosis, and ruled out by morphology and immunohistochemistry.

Conclusion
Our cases highlight the importance of awareness of the occurrence of leiomyosarcomas, a rare manifestation in bladder. Although rare, but they present with a poor outcome. The differential diagnosis of spindle cell lesions is extensive, including close benign and malignant mimics, the treatment of all being very different. Immediate radical cystectomy has been associated with longer survival rates for leiomyosarcoma. Leiomyosarcoma, being aggressive, with associated high recurrence rate and metastatic potential, an early correct diagnosis would aid in the institution of proper management.
Malignant Extrarenal Rhabdoid Tumor in a 5-Month-Old Male With Mediastinal and Heart/Great Vessel Involvement
Authors: Khokhar H , Craver R , Stark M 
Published: October 2020

Abstract

Introduction/Objective
Extrarenal rhabdoid tumor is a high-grade soft-tissue predominately pediatric malignancy with a frequency of 0.15 per million children less than 15 years. It is associated with del(22) (q11.2) with SMARCB1 loss, recognized by loss of INI-1 staining. It has distinct perinuclear hyaline inclusions; however, this feature can be present in other tumors. We describe a malignant extrarenal rhabdoid tumor involving the heart and great vessels to highlight the multiple modalities required for the diagnosis of this tumor in this unusual location.

Methods
We utilized routine histology, immunohistochemistry, and electron microscopy.

Results
This 5 -month -old male presented with respiratory distress due to a mass that invaded the heart, surrounding the great vessels. The tumor was composed of sheets of polygonal large cells with light pink to clear cytoplasm, eccentric nuclei with mild anisonucleosis, peripherally marginating chromatin, prominent nucleoli, with 2 mitoses per 10 high power field. Hyaline perinuclear inclusions were inapparent. There were frequent clusters of lymphocytes and eosinophils, with 10 percent necrosis and moderately increased vascularity. The tumor was positive for vimentin, SMA, EMA, MSA, S-100, keratin, and WT1, and negative for INI-1, CD34, ALK, AFP, PLAP, CD30, myogenin, NeuN1, synaptophysin, chromogranin, and NSE. Electron microscopy demonstrated occasional cells with perinuclear collections of intermediate filaments, some with whorls. The strong positivity for vimentin, keratin, SMA, MSA, S-100, negative staining for INA-1 and CD34, and visualization of perinuclear intermediate filament whorls by electron microscopy helped make the diagnosis of extrarenal rhabdoid tumor.

Conclusion
Malignant extrarenal rhabdomyosarcomas may occur in the middle mediastinum, invade the heart, occur in the first 6 months of life, and not have the typical rhabdoid cells. Diagnoses depend on multiple modalities
Abdominal Inflammatory Myofibroblastic Tumor: Minimal Inflammatory Infiltrate and Diffuse Immunoreactivity for Caldesmon are Potential Diagnostic Pitfalls
Authors: Alawad M , Dehghani A , Levitan D , Cruickshank K 
Published: October 2020

Abstract

Introduction/Objective
Inflammatory myofibroblastic tumor (IMT) is an uncommon spindle cell lesion that can involve various organs and occurs in multiple body sites. While older terminology (i.e. inflammatory pseudotumor) suggested otherwise, recent molecular studies point toward a neoplastic pathogenesis for IMTs. Herein, we report a case of an abdominal IMT and discuss the morphologic and immunohistochemical pitfalls pertaining to this entity.

Methods
A 75-year-old woman presented with complaints of generalized abdominal pain and distention. An abdominal CT scan showed multiple peritoneal masses, the largest of which measured 23 cm. Biopsy revealed compact fascicles of bland spindle cells exhibiting diffuse actin and caldesmon immunoreactivity, consistent with a spindle cell tumor with smooth muscle differentiation. Mitotic activity was low-to-unapparent. Surgical excision was performed. The cut surface of the tumor was tan-white with hemorrhagic foci. Histopathologic examination of the tumor showed elongated spindle cells set in a loose myxoid stroma rich in blood vessels and a mixed inflammatory infiltrate. Deeper sections of the tumor were more cellular, showing a similar morphology to that seen in the original biopsy, which was virtually devoid of inflammatory cells. Immunohistochemistry showed diffuse staining for desmin, caldesmon, smooth muscle actin, and ALK. FISH analysis showed ALK gene rearrangement in 52% of tumor cells, confirming the diagnosis of IMT.

Results
Studies in the literature show that IMTs express smooth muscle markers such as SMA (90%) and desmin (50%). However, immunoreactivity for caldesmon is rarely reported. ALK immunoreactivity is seen in about 35–60% of cases, and when gene rearrangement involving ALK is detected the diagnosis can be confirmed.

Conclusion
Historically, several terms have been used to describe IMTs, including inflammatory pseudotumor and inflammatory pseudosarcomatous fibromyxoid tumor. While the nomenclature consistently implies an inflammatory infiltrate, this tumor could have various morphological patterns with some areas showing very little to absent inflammation, as demonstrated in our case. Hence, making an accurate diagnosis could be challenging on a limited biopsy. Therefore, ALK testing should be included as part of the diagnostic workup of spindle cell neoplasms with smooth muscle differentiation.
Benign Rete Testis Mimicking as a Small Cell Carcinoma in a Hydrocele Specimen – A Rare Finding in a Veteran Patient and a Diagnostic Pitfall
Authors: Dalal S , Petersen J M , Jhala D 
Published: October 2020

Abstract

Introduction/Objective
Hydrocele specimens are one of the most common and routine urological specimens sent to pathology with mostly a benign outcome. Microscopic examination usually reveals loose connective tissue, mesothelial lining and possibly chronic inflammation, squamous metaplasia in long standing cases.

Methods
We present here a case of a veteran with rare finding of small, blue clusters of hyperchromatic cells in a hydrocele specimen mimicking small cell carcinoma.

Results
An elderly African American patient presented to the urology with a symptomatic hydrocele for elective removal. His review of systems preoperatively and intraoperative finding was otherwise unremarkable. Gross examination of the specimen showed a fibro-membranous tissue without any nodules or lesions. Microscopic examination showed fibromuscular tissue with scattered, detached clusters of small, blue, hyperchromatic cells with high nucleo-cytoplasmic ratio, nuclear molding without prominent nucleoli. Morphologically these features were suspicious for malignancy such as small cell carcinoma. However, no apparent mitotic figures or necrosis was noted. On immunohistochemical stains, these cells showed expression of CD 56, however proliferation rate on Ki67 was very low (0–1%).

Conclusion
Non-neoplastic proliferations are rare in testis and para-testicular structures. Rete testis is an anastomosing network of delicate channels located in the testicular hilum lined by flattened cuboidal to columnar epithelium with numerous microvilli. In a long-standing hydrocele specimen, the cells of rete testis may get sloughed off and form aggregates of small, blue hyperchromatic cells, morphologically mimicking as small cell carcinoma.
However, on close examination, these cells in cluster were “streaming”, no necrosis, atypical mitotic figures or apoptotic cells were noted. Also, it has been well known that normal rete testis cells are positive for CD 56. Thus, low ki67 proliferation rate, CD 56 positivity and absence of necrosis or mitotic figures were consistent with sloughed rete testis cells. This is a very rare finding in a routine hydrocelectomy specimens, not only highlighting the importance of thoroughly grossing the specimens; at the same time, knowledge of this benign mimicker is important to avoid erroneous diagnosis and management.
Histopathological Spectrum in Pancreaticoduodenectomy Specimens: Fifteen Year Study from a Tertiary Care Centre in North India
Authors: Siddiqui S H , Kumari N , Krishnani N 
Published: October 2020

Abstract

Introduction/Objective
The periampullary region is histologically complex owing to the confluence of three different kinds of epithelia (duodenal, pancreatic, biliary) harbouring four types of cancers. Although anatomical proximity warrants a common surgical approach, overall survival depends largely on the type of surgical indication. Malignant epithelial tumors are the predominant indications, accompanied by a myriad of benign tumors and tumor-like lesions. We reviewed our archival pancreaticoduodenectomies to analyze the spectrum of these lesions.

Methods
All pancreaticoduodenectomy specimens received in Department of Pathology, from 2005–2019 (15 years) were analyzed for histological spectrum.

Results
A total of 786 pancreaticoduodenectomies were received with an overall M:F= 2.3:1 and age range 17–91 years. Of these, 94.4% were neoplastic (742 cases) and 5.6% were non-neoplastic. Benign neoplastic lesions (19 cases, 2.4%) included adenomyoma (7 cases, 0.9%), solid-cystic pseudopapillary tumor of pancreas (5 cases, 0.6%), intraductal papillary mucinous neoplasm (2 cases, 0.3%) and one case each of serous cystadenoma, mucinous cystic neoplasm, dermoid cyst, gangliocytic paraganglioma and Peutz-Jeghers polyp. Ampullary adenocarcinoma was the predominant malignant epithelial lesion (609 cases, 77.5%) followed by distal CBD cancer (43 cases, 5.5%), pancreatic head cancer (20 cases, 2.5%), neuroendocrine tumors (22 cases, 2.8%), carcinoma gallbladder (5 cases, 0.6%) and one case of ampullary adenosquamous carcinoma (0.1%). Non-epithelial tumors included 9 cases of GIST (1.1%), 3 of carcinosarcoma and one case each of leiomyosarcoma and lymphoma. Non-neoplastic lesions (3.2%) included 22 cases of chronic pancreatitis and one case each of xanthogranulomatous pancreatitis, lymphoplasmacytic slcerosing pancreatitis and xanthogranulomatous cholecystitis. Ectopic pancreas was rare (2 cases, 0.3%) and 16 cases (2%) were negative for any specific pathology.

Conclusion
This is the largest data on histological spectrum of pancreaticoduodenectomies from India. The malignant lesions form the major bulk (94%), however benign lesions also account for a substantial percentage of surgical indications. Among malignant lesions, ampullary cancers outreach far above pancreatic cancers in the Indian subcontinent.
A PAX-8-positive Female Urethra Adenocarcinoma: A Case Report with Diagnostic Challenges in Intestinal- Type Adenocarcinoma
Authors: Torrez M , Allen R , Zhou J 
Published: October 2020

Abstract

Introduction/Objective
Female urethra adenocarcinoma (FUA) in women is extremely rare, representing 0.02% of all women’s cancers and &lt;1% of cancers in the female genitourinary tract. Intestinal-type primary adenocarcinoma of the urethra is even rarer, with only one documented case to our knowledge. Furthermore, PAX-8 immunoexpression in this entity has not been reported. Here we report an intestinal-type primary urethral adenocarcinoma that developed from inflammation-related metaplasia in urethral diverticulum with positive PAX-8 staining.

Methods
Clinical chart review and microscopic examination on the lung, urethral, and vaginal wall biopsies and immunohistochemistry were performed.

Results
A 64-year-old female with a 32-pack-year history of tobacco use was found to have multiple pulmonary nodules on imaging. The tumor cells were positive for CK7, CK20, SAT-B2, and PAX-8 and negative for TTF- 1/Napsin and ER. Positive PAX-8 immunoexpression raised the possibility of a gynecologic/Mullerian primary.
Subsequent colonoscopy and imaging showed no evidence of colorectal or uterine tumors. The patient began having hematuria with intermittent urinary retention, and cystoscopy showed a 4 x 3 cm mass involving bladder neck circumferentially and invading into the vaginal wall. Urethral and vaginal tumor biopsies were performed. Morphologic examination of the urethral biopsy demonstrated intestinal metaplasia of squamous mucosa with transition from a mature to dysplastic phenotype where the adenocarcinoma originated from. The vaginal wall biopsy showed the same morphology. The urethral and vaginal wall biopsies showed a similar immunophenotype as the pulmonary nodule biopsy.

Conclusion
FUA is a rare, aggressive tumor that occurs in Skene’s glands. In our current case, however, it appeared to arise from inflammation-related metaplasia in urethral diverticulum. Another important finding of the case is the positive PAX-8 expression. Therefore in PAX-8 positive tumors, primary adenocarcinoma of lower urinary tract should be in the differential, along with gynecologic/Mullerian tumors.
Amyloid Deposition Within a Large Pelvic Chronic Expanding Hematoma
Authors: Montoya-Cerrillo D M , Diaz-Perez J A , Rosenberg A E 
Published: October 2020

Abstract

Introduction/Objective
Chronic expanding hematoma (CEH) is a relatively rare complication of trauma that is usually mistaken for a soft tissue neoplasm. The identification of amyloid protein is of paramount clinical importance to exclude serious conditions causing systemic amyloidosis.

Methods
The case was retrieved from the pathology files at the University of Miami Hospital (UMH). Morphology and special stains were reviewed. The study was approved by the Institutional Review Board at UMH.

Results
A 44-year-old man with past history of a stab wound in the left buttock in the 1990s, was admitted with worsening abdominal pain, constipation, urinary obstruction and acute kidney injury. CT-scan showed a large mass involving the left gluteal area and pelvic cavity involving urinary bladder causing outlet obstruction and bilateral hydroureteronephrosis. Multiple radiology-guided biopsies were taken all identifying only fibrin, blood cells, and necrotic inflammatory cells. Excision of the gluteal mass and drainage of the pelvic component was performed confirming the diagnosis of CEH. Amyloid deposition with congo red stain birefringence under polarized light was identified. The patient’s symptoms and renal function improved and have been under follow-up for 1 month.

Conclusion
We have identified amyloid protein deposition whiting a CEH. This is an unusual finding with no previous description found in our search. The identification of amyloid whiting tumor-like lesions is relevant to exclude causes of systemic amyloidosis.