bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rare Urinary Bladder Tumor with Unusual Morphology: A Potential Diagnostic Pitfall
Authors: Abdo M E , Walkenhorst M , AL-Kharouf I , Hamza A 
Published: November 2022

Abstract

Introduction/Objective
Transurethral resection of bladder tumor (TURBT) is a common surgical pathology specimen. The purpose of this report is to describe an unusual case encountered on a TURBT specimen with discussion of the differential diagnoses to avoid potential diagnostic pitfall.

Methods/Case Report
A 68-year-old male presented with history of urinary frequency, urgency and nocturia. Cystoscopy showed nodular, pedunculated lesion at the bladder trigone. Transurethral resection was performed. Histologic section showed a 4 mm polypoid lesion with classical appearance of cystitis glandularis and an adjacent area of relatively more atypical yet bland cells in tubular growth pattern. This elicited a differential diagnosis of nephrogenic adenoma / metaplasia, prostate type polyp / ectopic prostatic tissue and urothelial carcinoma with tubule formation. Immunohistochemical stains showed the lesional cells to be positive for high molecular weight cytokeratin and racemase (AMACR) and negative for GATA3, NKX 3.1, PAX-8, CK 7, CK 20, p63, PSA and PSAP. Literature review suggested that racemase is frequently positive in neuroendocrine tumors. Additional immunohistochemical stains performed showed the lesional cells to be positive for synaptophysin and chromogranin and negative for TTF-1 and CDX-2. Ki-67 proliferation index was less than 1%. Therefore, final diagnosis of well-differentiated neuroendocrine tumor, grade 1 involving urothelial mucosa was rendered. Patient did not have any history of prior malignancies. A subsequent PET / CT did not demonstrate any evidence of metastatic disease. Additional work up was also negative for carcinoid tumor of lung and well differentiated neuroendocrine tumor of gastrointestinal and pancreaticobiliary tracts. Multidisciplinary discussion recommended cystoscopy every 3 months for a year, then every 6 months for 2 more years and annually thereafter.

Results (if a Case Study enter NA)
n/a.

Conclusion
This case reminds pathologists that although rare, well differentiated neuroendocrine tumors can occur in the urinary bladder, they can show unusual histology with tubular growth, and can be racemase positive.
Eosinophilic Solid and Cystic Renal Cell Carcinoma with Non-typical Immunophenotype: A Series of Two Cases
Authors: Chen J , Harbert J , Bhalla R , Dewenter T 
Published: November 2022

Abstract

Introduction/Objective
Eosinophilic solid and cystic renal cell carcinoma (ESC RCC) is an emerging entity receiving increasing attention. Initially characterized in a large series by Trpkov et al, the distinct features of this tumor are voluminous eosinophilic cytoplasm with granular cytoplasmic stippling, mixed solid and cystic architecture, and CK20 positivity/CK7 negativity.

Methods/Case Report
We present two cases of ESC RCC diagnosed at our institution which exhibit a non-typical immunophenotype. The patients were a 58-year-old female and a 59-year-old male, with a 5.5 cm and 3.5 cm incidental renal mass, respectively. Both underwent uncomplicated partial nephrectomies. The tumors exhibited solid, alveolar, tubular and focally cystic growth patterns and were composed of cells with voluminous granular eosinophilic cytoplasm. Tubules and cysts were lined by single hobnail layer of neoplastic cells. Characteristic cytoplasmic stippling and compact leishmaniasis-like globules were present. The tumor nuclei were enlarged, with irregular nuclear contours and scattered multinucleation. The second case was significant for a diffuse neutrophil infiltration along with foamy macrophages. Immunohistochemically, the tumor cells were positive for PAX8, AMACR, CD10 and vimentin, while being negative for pan-cytokeratin, CD117, CAIX, Melan A, and HMB45. Interestingly, CK20 was only positive in very rare single cells and CK7 was focally positive in both cases. In our differentials, we considered SDH-deficient, low-grade FH-deficient, and MiT family translocation-associated RCC. FISH studies showed that the tumor cells have retained the expression of FH and SDHB, without TFE3 and TFEB alterations. Although our cases demonstrated non- typical CK20/CK7 expressions, based on the morphology with other molecular manifestations, the diagnosis of ESC RCC was rendered.

Results (if a Case Study enter NA)
NA.

Conclusion
ESC RCC poses diagnostic difficulties as many eosinophilic/oncocytic entities are included in the differentials, and the immunoprofile of this entity is variable. It is important to appreciate the characteristic histomorphologic features to increase its recognition as inclusion into the WHO classification system is likely.
Concurrent Prostatic Adenocarcinoma and Lymphoma: Clinicopathologic Study of 10 Cases
Authors: Cain S , Hamza A 
Published: November 2022

Abstract

Introduction/Objective
Synchronous and meta-synchronous hematolymphoid neoplasms and prostatic adenocarcinomas are known to occur, albeit rarely. The purpose of this study is to identify the clinicopathologic features of patients with coexisting prostatic adenocarcinoma and a lymphoma diagnosis.

Methods/Case Report
The institutional pathology archive was searched from 2016 to 2021. Data such as patient age, Gleason score, pathologic tumor stage, type of lymphoma and follow up data were collected.

Results (if a Case Study enter NA)
Ten patients were identified. Mean patient age was 65.4 ± 5.7 years. Nine specimens were prostatectomies and 1 was a needle core biopsy. Four patients had previous lymphoma diagnoses while 6 were diagnosed with lymphoma on lymph node dissection for prostatectomies. Seven patients had Gleason grade 3 + 4=7 disease, two had Gleason grade 4 + 3=7 and one had Gleason grade 4 + 5=9. Seven patients had small lymphocytic lymphoma/chronic lymphocytic leukemia, one had follicular lymphoma, one had mantle cell lymphoma and one had peripheral T-cell lymphoma. The patient with peripheral T-cell lymphoma died 18 months after lymphoma diagnosis and 11 months after prostate cancer diagnosis. The remaining 9 patients were alive for a mean of 27.7 ± 22.6 months after prostate cancer diagnosis.

Conclusion
There is minimal literature on patients with synchronous/meta-synchronous hematolymphoid neoplasms and prostatic adenocarcinoma. Our data provides one of the largest institutional series in this regard. Additional data and follow up is needed to evaluate if the concurrent low grade hematolymphoid malignancy, specifically small lymphocytic lymphoma/chronic lymphocytic leukemia, affects the survival outcome in these patients.
Sarcomatoid Chromophobe Renal Cell Carcinoma with Heterologous Elements: A Rare Form of an Aggressive Tumor
Authors: Hosseini H , Sham S , Unger P , Brodherson M S 
Published: November 2022

Abstract

Introduction/Objective
Chromophore renal cell carcinoma (ChRCC) accounts for approximately 4-10% of renal cell carcinomas. Compared with other subtypes of renal cell carcinoma, ChRCC generally has a more favorable outcome; however, sarcomatoid transformation is greatest in ChRCC. We report a case of ChRCC with extensive sarcomatoid transformation, which included the heterologous elements of osteosarcoma and chondrosarcoma. The presence of heterologous elements is distinctively rare, with only twelve previous cases in the English literature.

Methods/Case Report
A 64-year-old man presented with left flank pain and night sweats. The abdominal MRI showed a large exophytic hypervascular mass in the left kidney with metastasis to the left para-aortic lymph nodes. The patient underwent radical nephrectomy. Two months after the surgery, the patient was found to have extensive bony metastases. On gross examination, the nephrectomy specimen showed an 18 cm tumor replacing almost the entire kidney. The cut surface was white to tan with areas of hemorrhage and necrosis. Microscopic examination revealed a predominantly sarcomatoid ChRCC (nearly 80% of the tumor) with heterologous chondrosarcoma and osteosarcoma. The tumor extended into the perinephric adipose tissue and the adrenal gland. Multiple para-aortic lymph nodes contained sarcomatoid tumor with heterologous elements.

Results (if a Case Study enter NA)
NA.

Conclusion
ChRCC is frequently considered a more indolent renal cell carcinoma. It is important to recognize its higher propensity for sarcomatoid transformation. The presence of heterologous elements is exceptionally uncommon. Whether this correlates with a more aggressive tumor is not known because of the paucity of such cases.
Pitfalls in Pathology-Fibroepithelial Stromal Polyp of the Bladder
Authors: Li L 
Published: November 2022

Abstract

Introduction/Objective
The fibroepithelial stromal polyp is a benign polypoid proliferation of the stroma with overlying, usually squamous epithelium. It was originally reported in 1966 and is a generally recognized lesion of the female genital tract. Because the lesion contains atypical stromal cells, it can be mistaken for a sarcoma, particularly if it shows hypercellularity, pleomorphism, and atypical mitoses. It is often found in the female lower genital tract, urethra, and rarely extragenital sites, such as the breast. Other unusual locations such as the anus and nasal cavity have also been reported. The lesion is hormonally related and affects mostly reproductive-age women. Rare cases were reported in the male urinary tract and genital area. Because it is not well known in the bladder, overinterpretation as a sarcoma is possible.

Methods/Case Report
We report a ~60-year-old patient with a history of lower urinary tract symptoms due to prostatic hypertrophy on maximal medical therapy. He had been experiencing hematuria. On office cystoscopy, he was found to have a 3 cm prostate mildly obstructing the urethra, and 2 small velvety, erythematous patches on the posterior bladder wall. At cystoscopy, he was seen to have a small posterior bladder lesion, which was resected without difficulty. The pathology laboratory received two fragments of pink/tan soft tissue measuring 0.1 and 0.2 cm in the greatest dimension. On histology, the overlying urothelium was benign. The stroma was collagenous and hypocellular, containing scattered atypical and multinucleated cells, similar to the fibroepithelial stromal polyp well recognized in the female lower genital tract.

Results (if a Case Study enter NA)
N/A.

Conclusion
Benign fibroepithelial stromal polyp is an uncommon lesion usually seen in the lower genital tract of reproductive aged women. The presence in the bladder of a male is exceptionally rare. Recognition of the lesion will prevent overdiagnosis as a malignancy.
Endometrial Serous Adenocarcinoma with Septate Uterus: A Rare Case Report
Authors: Zedan M A , Wei E 
Published: November 2022

Abstract

Introduction/Objective
Congenital structural malformations of the uterus rarely coincide with uterine malignancies and can cause significant challenges to the detection of tumors originating from the uterine cavity. We report a case of delayed diagnosis of endometrial high-grade serous adenocarcinoma following an initial false-negative endometrial biopsy result. A septate uterus was discovered incidentally upon gross dissection, and it was recognized as the cause of the initial false-negative biopsy result. Exceptionally rare cases of uterine malformation combined with carcinoma have been reported in the literature and we are sharing this case to provide further awareness of such clinical scenario.

Methods/Case Report
A 67- year-old multigravida (G3P2103) female presented with postmenopausal bleeding. Initially, the patient underwent an endometrial biopsy revealing strips of benign glandular epithelium. Three months later endometrial biopsy showed high-grade serous carcinoma. A computed tomography scan (CT) of the abdomen and pelvis showed expanded and heterogeneously hypodense endometrium. The patient underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Gross examination of the specimen revealed a septate uterus with two cavities. Within the right cavity, there was an infiltrating polypoid mass and a superficial benign-appearing endometrial polyp was identified in the left cavity. After histologic examination of the right cavity mass, a diagnosis of endometrial high-grade serous adenocarcinoma was rendered.

Results (if a Case Study enter NA)
N/A

Conclusion
Congenital structural malformations of the uterus carry a higher risk of delayed or missed uterine cancer diagnosis. Septate uterus is associated with a higher chance of failed endometrial biopsy and can result in a false- negative outcome. The use of hysteroscopy, hysterosonography, and three-dimensional ultrasound could improve the diagnostic modality of malignant uterine tumors associated with structural malformations.
Uterine Leiomyosarcoma with a Novel RAB2A-PLAG1 Gene Fusion
Authors: Hosseini H , Vele O , Unger P , O'Leary X , DiNapoli S E , Mullaney K , Zaidinski M , Sukhadia P , Benhamida J K , Soslow R A , Villella J A 
Published: November 2022

Abstract

Introduction/Objective
Uterine leiomyosarcoma is a malignant neoplasm with three distinct histologic subtypes: spindle, epithelioid, and myxoid. Distinguishing leiomyosarcoma from mesenchymal uterine neoplasms such as endometrial stromal sarcoma can be challenging as they may exhibit a similar histology and immunohistochemical profile. In such cases, molecular studies can help achieve the definitive diagnosis. It has been shown that ~25% of the uterine myxoid leiomyosarcomas harbor TRPS1-PLAG1 and RAD51B-PLAG1 gene fusions. To our knowledge, no uterine leiomyosarcoma with RAB2A-PLAG1 gene fusion has been previously reported in the English literature.

Methods/Case Report
An 80-year-old woman presented with abnormal uterine bleeding. A large necrotic uterine mass with no evident lymphadenopathy was detected on imaging. Endometrial curettage demonstrated a malignant mesenchymal neoplasm that was positive for CD10, desmin, and vimentin and lacked expression of SMA, SMMH, synaptophysin, and chromogranin. AE1/AE3 highlighted rare foci. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy. The hysterectomy specimen was notable for a 10.8 cm rubbery focally calcified tan- white mass histologically composed of high-grade spindle and epithelioid cells with hypocellular and hyalinized areas. The mitotic activity was &gt;25/10HPF. Immunohistochemically, the neoplastic cells expressed CD10, caldesmon, desmin (patchy), SMA (weak focal), and CAM5.2 (patchy) while they were negative for ER, PR, HMB45, AE1/AE3, WT1, cyclin D1, BCOR, myogenin, pan-NTRK, and ALK. P53 staining showed a wild type expression pattern.
Histology and immunohistochemistry could not definitively differentiate between leiomyosarcoma and high grade endometrial stromal sarcoma. RNA sequencing identified a RAB2A-PLAG1 gene fusion. In light of the histology and ancillary studies, a diagnosis of leiomyosarcoma was rendered.

Results (if a Case Study enter NA)
NA

Conclusion
This is the first case of a uterine leiomyosarcoma with RAB2A-PLAG1 gene fusion. Pathologists should be cognizant of the extensive morphologic and immunophenotypic overlap between various uterine mesenchymal neoplasms. In challenging cases, molecular analysis is crucial in allowing the pathologist to arrive at the final diagnosis.
Two Giant Placental Chorangiomas Discovered at 34 week’s Gestation: A Case Report
Authors: Amer S , Yin J , Hennawy H 
Published: November 2022

Abstract

Introduction/Objective
Chorangioma is a benign vascular tumor of the placenta, likely hamartoma, occurring in 1% of all examined placentas and arising from the primitive chorionic mesenchyme. The clinical significance is related to the size of the tumor. Most chorangiomas are small and asymptomatic; however, those larger than 4 cm are associated with intrauterine growth restriction (IUGR), polyhydramnios, preterm delivery, arteriovenous shunting, hydrops, and fetal thrombocytopenia.

Methods/Case Report
Herein, we present a case report of a placenta with two chorangiomas that are prenatally detected in a 25-year-old G2P1 female patient by ultrasound which showed a placental mass and mild polyhydramnios. The patient also developed hypertension and preeclampsia so she was referred for early induction of labor. The patient was elected for caesarian section and the placenta was delivered at 35 weeks of gestation. Grossly, two tan soft well-circumscribed lobulated placental masses were identified and measured 9.5 x 9.1 x 3.3 cm and 5.5 x 4.5 x 1.9 cm, respectively. The two masses were joined together by a thick blood vessel. The larger 9.5 cm mass was connected to the placental disc at the umbilical cord insertion site and is associated with blood vessel thrombosis. Microscopically the mass showed proliferation of capillary-sized vessels with surrounding stroma consistent with chorangioma. Clinical, radiological, and microscopic profiles support the diagnosis of placental chorangioma.

Results (if a Case Study enter NA)
N/A

Conclusion
To our knowledge, this is the first case report of two giant placental chorangiomas connected together by a thick blood vessel. Although both are giant (more than 4 cm), early diagnosis and timely intervention led to good maternal and neonatal outcomes aided with neonatal intensive care unit management.
S-100 Negative Granular Cell Tumor of Oral Cavity with Aggressive Clinical Behavior
Authors: Mohamed R , Givi J P , Bacaj P 
Published: November 2022

Abstract

Introduction/Objective
Granular cell tumors (GCTs) are neoplasms with neuroectodermal (Schwann cell) differentiation that is typically benign and cured by surgical excision. These tumors characteristically display strong expression of S-100 protein. Similar tumors without expression of S-100 protein are called “S-100 negative granular cell tumors.” The few reported cases of S-100 negative GCT in the oral cavity describe indolent clinical behavior. We report a case of a 49-year-old male with recurrent S-100 negative GCT in the oral cavity.

Methods/Case Report
The patient presented initially with a mass in the hard palate, which was resected and diagnosed as an S-100 negative GCT. One year later, the patient developed severe epistaxis and anemia (hemoglobin 7.2 g/dL). A large tumor of the hard palate was the source of bleeding. It was resected and diagnosed as recurrent S-100 negative GCT. Histologically, this tumor consists of small nests of epithelioid to spindled cells with moderately abundant granular eosinophilic cytoplasm, round central nuclei with vesicular chromatin and distinct eosinophilic nucleoli, and significant mitotic activity. The cells are immunoreactive for SOX10 and negative for S-100, melan-A, keratin AE1/AE3, p40, synaptophysin, smooth muscle actin, desmin, and myogenin.

Results (if a Case Study enter NA)
N/A

Conclusion
S-100 negative GCTs are rare, and only a few case reports describe their involvement in the oral cavity. We report this case because of its rarity and aggressive clinical behavior. Recognition of this entity and its potential for locally aggressive growth is important. Management of this tumor by complete excision seems advisable.
Adenoid cystic carcinoma of the orbit: a single institute experience
Authors: Deb P Q , Mirani N 
Published: November 2022

Abstract

Introduction/Objective
Adenoid cystic carcinoma (ADCC) is a malignant neoplasm usually arising from the major and minor salivary glands. Orbital ADCC arising from the lacrimal gland is rare. They present with morphology and immunohistochemical properties identical to their salivary gland counterparts. Due to their rarity, orbital ADCCs are poorly studied. Here, we describe our institutional experience of diagnosing ADCC in orbit.

Methods/Case Report
We queried the electronic laboratory information system for primary tumors arising in the orbit that resulted in the diagnosis of ADCC in the last twenty years. Clinical history, radiology, and immunohistochemical profile were obtained and summarized for all cases.

Results (if a Case Study enter NA)
Eight cases were with the diagnosis of orbital ADCC. The age at diagnosis ranged between 38 to 79 years, with most patients diagnosed between 41 to 50 years. The male to female ratio was 1:1. The tumor size varied between 1.5 to 8.7 cm. Most tumors were graded as grade III and showed perineural invasion. Five out of eight tumors showed predominantly solid architecture. The immunohistochemical pattern was similar to salivary gland ADCC, with one case showing MYB rearrangement.

Conclusion
Our data suggest that orbital ADCC closely resembles their salivary gland counterparts. Although small, our study broadens the general understanding of this rare group of malignancies.
Mandibular Solitary Intraosseous Myofibroma: A Case Report and Review of Literature
Authors: Lazim A , Kuklani R , Laski R 
Published: November 2022

Abstract

Introduction/Objective
Myofibroma (MF) is a benign soft tissue neoplasm of myofibroblastic origin, which frequently occurs in children and rarely presents as an intraosseous neoplasm. Other benign mesenchymal lesions and other low-grade malignant soft tissue neoplasms mimic morphologically to MF, thus making the diagnosis of MF challenging and crucial.

Methods/Case Report
Herein, we describe a 9-year-old female who was referred to an oral surgeon by her dentist, for evaluation of a radiolucent lesion on her left mandible associated with impacted tooth #21 and 22, which had slightly increased in size over 2 weeks. Her medical history was non-contributory other than asthma. Clinical examination revealed a large 5x4 cm firm mass slightly tender and causing expansion along the buccal as well as lingual aspects of the mandible in the canine and first premolar region. A radiograph CBCT of the mandible revealed malposed tooth #21 and 22 and unilocular radiolucency associated with the crowns #21 and 22. No evidence of calcifications within the lucency was noted. The patient underwent an incisional biopsy of the mandibular lesion, which showed a benign tumor composed of bland spindled cells arranged in fascicles with scattered thin walled blood vessels. Mitotic figures were inconspicuous and there was no discernible necrosis. Immunohistochemical stains show that the lesional cells are positive for SMA and Vimentin (Fig. 1 A-D, H&E, SMA, Ki-67, Vimentin) and negative for S100, desmin and CD34. Ki-67 (proliferative index) is interpreted to be low (&lt;5%).

Results (if a Case Study enter NA)
NA

Conclusion
Mandibular intraosseous MF is extremely rare. Clinico-pathologic correlation, immunohistochemical features and sometimes molecular studies are essential for correct diagnosis and to rule out other benign and low-grade soft tissue neoplasms that mimic MF morphologically and radiographically. Thus MF, though rare neoplasm should be considered in the differential diagnosis of unilocular or multilocular radiolucent lesions of the jaws.