A giant leiomyoma of the breast

Breast leiomyoma is a rare benign tumor arising from the nipple and/or areola or from smooth muscle metaplasia of myoepithelial or myofibroblast cells. Despite its benign morphology, breast leiomyoma can create diagnostic confusion. Here, we report a rare case of a single leiomyoma of the breast in a 52-year-old woman. The patient reported a lump in her right breast for 1 year, and in the past 6 months, it has grown in size. Physical examination showed a dense mass in the right breast, without axillary lymphadenomegaly. Excisional biopsy revealed a well-defined cell tumor by intertwining the spindle cell folds with fibrillar and eosinophilic cytoplasm. Histopathological and immunohistochemical studies help to discriminate between leiomyoma and other benign and malignant breast lesions. Her results are discussed in our report.

Scrotal hemangiosarcoma in a Large White boar

ABSTRACT: Tumors are rarely diagnosed in swine specie because of the short lifespan of production animals. Normally, these tumors do not present any clinical signs and are often detected at the time of slaughter. A 2-year-old Large White boar, used in the reproductive management of a farm and without a history of pre-existing problems, was examined for skin lesions on the scrotum. Samples were collected from skin segments containing lesions for histopathological and immunohistochemical diagnosis. Microscopically, the nodes in the scrotum pouch consisted of poorly demarcated, highly cellular, expansile, and multifocally invasive neoplasms, composed of immature endotheliocytes organized into neovascular formations. The tumor cells were pleomorphic, slightly oval to spindle-shaped, with eosinophilic cytoplasm and hyperchromatic nuclei with one to three nucleoli. All the nodules analyzed were compatible with hemangiosarcoma. After immunohistochemical evaluation, for the quantification of tissue angiogenesis the neoplastic cells immunoexpressed the CD31 monoclonal antibodies and factor VIII, through the identification of proteins expressed on the surface of endothelial cells. The Ki67 cell proliferation marker was positive in approximately 10% of the neoplastic cells, demonstrating a high degree of malignancy. Hemangiosarcoma in swine species has already been identified in several organs and tissues; however, to date, no study has demonstrated the diagnosis of this condition on the skin of the scrotum, as reported in this study. Therefore, it is expected that this report will contribute to the knowledge of the frequency of neoplasms in swine species.

Triple-negative apocrine carcinoma as a rare cause of a breast lump in a Syrian female: a case report and review of the literature

Background Apocrine carcinoma is a rare tumor that constitutes < 4% of all breast malignancies, characterized by the proliferation of large atypical cells with strictly defined borders, abundant eosinophilic cytoplasm, large nuclei, and prominent nucleoli in more than 90% of tumor cells. Triple-negative apocrine carcinoma is a rare molecular subtype that constitutes less than 1% of triple-negative breast cancers and is characterized by negative expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor, with positive expression of androgen receptor. Case presentation We report a case of a 45-year-old Syrian female who presented to our hospital due to a painless palpable mass in her left breast. Following physical and radiological examinations, an excisional biopsy was performed. Microscopic examination of the specimen followed by immunohistochemical staining revealed the diagnosis of a triple-negative apocrine carcinoma. Conclusion Triple-negative apocrine carcinoma is an extremely rare neoplasm that must be considered in the differential diagnoses of breast lesions through detailed clinical, histological, and immunohistochemical correlations. In our manuscript, we aimed to present the first case report of a Syrian female who was diagnosed with a triple-negative apocrine carcinoma, aiming to highlight the importance of detailed clinical, histological and immunohistochemical correlations with a detailed review of diagnostic criteria, molecular characteristics, and treatment recommendations.

Plexiform Cellular Schwannoma in Infancy and Childhood: A Clinicopathological Study of Seven Cases of an Underrecognized Nerve Sheath Tumor with a Tendency Toward Local Recurrence

Plexiform cellular schwannoma (PCS) is very rare, and it is not completely understood. We present our experience with 7 additional cases of PCS in infancy and childhood to further characterize its distinctive clinicopathological features. There were 5 females and 2 males with a mean age of 28 months (ranging, 2 months to 8 years). The involved sites included the left forearm ( n = 2), sacrococcygeal region ( n = 2), retroperitoneum ( n = 1), thoracic spinal canal and thoracic cavity ( n = 1), and neck ( n = 1). Tumor sizes ranged from 3 to 13 cm in maximum diameter (mean, 7.1 cm). Histologically, all tumors consisted of abundant spindle cells arranged in a multinodular or plexiform growth pattern, possessing elongated, hyperchromatic nuclei and pale eosinophilic cytoplasm with indistinct cell margins. Mitotic figures were easily identified, with a mean count of 4 per 10 consecutive high power fields (HPF). Immunohistochemically, all tumors were strongly and diffusely positive for S100 protein, SOX10 and H3K27me3. The Ki-67 index ranged from 5% to 30% (mean, 15%). Follow-up (available in 6 cases) revealed that 5 patients experienced local recurrence and were treated by re-excision. There was no evidence of recurrence and metastasis in 3 patients, and the other 2 were alive with the disease. In conclusion, PCS is an uncommon nerve sheath tumor predominantly occurring in infants and children, featuring a plexiform or multinodular growth pattern and exhibiting a tendency toward local recurrence. PCS is easily mistaken as malignant peripheral nerve sheath tumor (MPNST) due to its locally aggressive behaviors and worrisome features, including hypercellularity, hyperchromatism and high proliferative activity. Increased awareness of its potential occurrence and greater familiarity with its characteristic features are helpful for both clinicians and pathologists to avoid misdiagnosis and unnecessary overtreatment.

Primary Hemangioblastoma of Kidney with Molecular Analyses by Next Generation Sequencing: A Case Report and Review of the Literature

Background: Hemangioblastoma is an indolent mesenchymal tumor most frequently occurring in the central nervous system (CNS), but can also arise extraneuraxially, as part of von Hippel-Lindau (VHL) disease or in sporadic cases. Extraneuraxial hemangioblastomas (EH) occur outside the central nervous system. It includes tumors arising from the nervous paraneuraxial structures and visceral organs. Sporadic hemangioblastoma of the kidney, a rare subset of EH, is an under-recognized renal neoplasm. There have been only 25 cases described to date in the English language literature. We report herein one additional case in a patient without VHL disease.Case presentation: A 61 year old male presenting with gross hematuria was found to have a 3.5 cm renal mass at the lateral mid to lower pole of the left kidney on computed tomography urogram. Patient underwent a partial nephrectomy for the mass. The pathological examination showed a well-circumscribed non-encapsulated tumor composed of sheets of large polygonal cells traversed by a rich vascular network. The tumor cells showed clear to eosinophilic cytoplasm and overall bland nuclei. The diagnosis of hemangioblastoma was confirmed by positive immunostaining for alpha-inhibin, S100, neuron-specific enolase, PAX8, and negative staining for epithelial membrane antigen, HMB-45, and Melan-A. VHL gene mutation was not detected in this tumor. The diagnosis of sporadic renal hemangioblastoma was made.Conclusion: Sporadic renal hemangioblastoma (RH) is a rare subset of EH. We report herein one such case in a patient without clinical or molecular evidence of VHL disease. We reviewed the literature to better understand the clinical, radiological and pathologic features of this neoplasm. From our review cases and the present case, we have found that the majority of RHs showed a positive immunostaining for PAX8, which supports the idea that the immunoprofiles of EH can vary depending on sites of origin. Diagnosis of renal hemangioblastoma is challenging because of its rarity and overlapping microscopic and immunophenotypic features with renal cell tumor, especially with clear cell renal cell carcinoma. However, accurate diagnosis is necessary, since RH is clinically benign and correct recognition of this pathological entity is important to avoid unnecessary over treatment.

Case report: A EWSR1-CREM-Rearranged Gastric Mesenchymal Tumor Accompanied by Gastritis Cystica Profunda and with Probable Benign Behavior

Background:Genomic rearrangements involving EWSR1 and the CREB family of transcription factors are increasingly detected in an array of mesenchymal neoplasms, including clear cell sarcoma-like tumors of the gastrointestinal tract (CCSLGT), a gastrointestinal malignancy. Gastritis cystica profunda (GCP) is a rare disease characterized by cystic dilatation of gastric glands into the submucosa and generally regarded as a precursor to tumor.Case presentation:Herein, we report a peculiar case in which a EWSR1-CREM-rearranged gastric mesenchymal tumor was admixed with GCP in a gastric fundic mass in a 64-year-old woman. Histologically, the mass showed readily distinguishable epithelial and mesenchymal components. All layers of the gastric wall were invaded, although no lymph node or neural invasion, or tumoral vascular emboli was noted. The epithelial component consisted of foveolar-type glands interspersed with pyloric-type ones, with glands showing metaplastic growth. Most glands were elongated with irregular contour, with some forming cystic structures containing eosinophilic secretory material. The epithelial cells showed focally atypical hyperchromatic nuclei, inconspicuous nucleoli, slightly eosinophilic cytoplasm, and infrequent mitosis. The mesenchymal component consisted of monomorphic, ovoid-shaped cells often arranged in sheets surrounding the glands. These cells displayed scanty cytoplasm, regular nuclei, and rare mitotic figures. Immunohistochemically, the epithelial cells were uniformly positive for cytokeratins and negative for markers of neuroendocrine differentiation, and the mesenchymal neoplasm showed focal positivity for CD10, CD117 and CD56 as well as negativity for cytokeratin, neuroendocrine markers, DOG-1, CD34, SMA, desmin, HMB-45, Melan A, and S-100. An EWSR1-CREM fusion was identified with genomic profiling and confirmed with fluorescence in situ hybridization in the tumor. Given the low mitotic activity, absence of nodal or distant spread and vascular or neural invasion, and the disease-free status at 28-month follow-up, both lesions were likely benign. Conclusions:To our knowledge, this is the first to report a EWSR1-CREM fusion in a gastric mesenchymal tumor with accompanying GCP. Whether this case suggests a novel entity or falls into one of proposed classes awaits report of more similar cases and insights into the relationship between GCP pathogenesis and oncogenesis.

Malignant Gastrointestinal Neuroectodermal Tumor: a case report and a review of the literature

Introduction/Objective Malignant gastrointestinal neuroectodermal tumor (GNET) is a rare soft tissue tumor arising in the wall of the gastrointestinal tract. The GNET was first described as an osteoclast rich tumor of the gastrointestinal tract with features resembling clear cell sarcoma, with only few cases reported in the literature. Methods/Case Report We report a case of a 71-year-old man with a past medical history of hypertension, hyperlipidemia, and benign prostatic hyperplasia presented with complaints of dyspnea, dizziness, fatigue, black stools, and a recent syncopal episode. Laboratory testing revealed anemia (HB 5.4 g/dL). Esophagogastroduodenoscopy demonstrated a submucosal gastric mass. An abdominal CT scan confirmed a 7.8 cm mass along the gastric cardia and fundus. Results (if a Case Study enter NA) Biopsy rendered a gastrointestinal neuroectodermal tumor (GNET). Microscopically, the tumor cells were spindle with eosinophilic cytoplasm and arranged in fascicules. They were positive for CD56, CD99, and Fli-1, synaptophysin, and negative for chromogranin, TTF-1, SMA, desmin, CD34, EMA, pan-cytokeratin, and lymphoid markers. Two months later, further imaging confirmed metastasis to the liver and spleen. GNETs typically arise within the muscularis propria of the gastrointestinal tract and often extend into the submucosa and subserosa. Conclusion The most important differential of GNET is the clear cell sarcoma of the gastrointestinal tract (CCS-GI). Both share similar morphological as well as molecular features and show S100 positivity; however, the lack of melanocytic differentiation in GNET distinguishes it from CCS-GI. Both typically show rearrangements of the EWSR1 gene, with t(12;22) (q13;q12) EWSR1-ATF1 or t(2;22)(q34;q12) EWSR1-CREB1 fusions. Pathologists should be aware of GNET diagnostic entity due to its aggressive behavior and high rate of recurrence and mortality even after complete resection.

Extrauterine Epithelioid Trophoblastic Tumor (ETT) Arising from an Antecedent Undiagnosed Molar Pregnancy Presenting as an Adnexal mass: A Case Report

Introduction/Objective Epithelioid trophoblastic tumor (ETT) is an extremely rare neoplasm derived from chorionic type intermediate trophoblast. ETT usually follows an antecedent term pregnancy but can also follow spontaneous abortions or molar pregnancy. ETT most often arises from the endometrium, followed by the cervix. Extrauterine ETT are extremely rare, with few cases reported in literature. Methods/Case Report A 41-year-old woman with three term pregnancies presented with abdominal pain, ten years after her last pregnancy. Imaging findings of a 3.5 cm adnexal mass coupled with an elevated serum β-hCG (~ 900 mIU/ml), led to the suspicion of an ectopic pregnancy. Hysterectomy with salpingectomy revealed a 4.7 cm, tan- yellow, necrotic mass in the adnexal region abutting but distinct from the uterine serosa. Histologic evaluation showed a well- circumscribed tumor with pushing borders. The tumor cells were epithelioid with well-defined eosinophilic cytoplasm, monomorphic nuclei, frequent mitosis, and abundant geographic necrosis. The tumor cells were positive for β-hCG, GATA-3, PLAP and inhibin, with focal weak staining squamous markers p63 and p40. DNA fingerprinting analysis, performed to confirm the diagnosis of ETT, revealed a homozygous tumor with two copies of non-maternal genes indicating that the antecedent index gestation giving rise to the tumor was an undiagnosed hydatidiform mole. Following surgery, serum β-hCG levels were normal and the patient is currently on surveillance. Results (if a Case Study enter NA) NA Conclusion We present an extremely rare case of extrauterine ETT arising from a previously undetected molar pregnancy. The diagnosis should be suspected when a mass is observed at extrauterine sites with elevated β-hCG levels in patients with or without vaginal bleeding. Histologic differential of squamous cell carcinoma needs to be ruled out with immunostains. Due to its rarity and highly variable presentation, this entity remains a diagnostic challenge. DNA fingerprinting analysis demonstrating non-maternal genes can help confirm the diagnosis of ETT.

Case of renal cell carcinoma with immunotherapy effect mimicking xanthogranulomatous pyelonephritis

Introduction/Objective The histologic features of renal cell carcinoma (RCC) after immunotherapy are not fully established. We report the pathologic findings of one case of clear cell RCC after treatment with pembrolizumab which is a humanized monoclonal anti-PD1 antibody. Methods/Case Report 46-year-old man completed three cycles of pembrolizumab for recurrent basal cell carcinoma. A 5.0 cm mass was incidentally found within left kidney during staging CT scan. He subsequently had left radical nephrectomy. Pathologic examination of nephrectomy specimen identified one 5.0 cm, well-circumscribed, solid mass in the upper pole, confined to the kidney with predominantly hemorrhagic, focally golden-yellow soft cut surface. The remaining parenchyma appears unremarkable. The pelvicalyceal system is not dilated. Sections of tumor show predominance of foamy histiocytes, lymphoplasmacytic infiltrate, and scattered cells having pale or eosinophilic cytoplasm, conspicuous nucleoli and low nuclear: cytoplasm ratio. Cholesterol clefts and hemosiderin deposits are noted. The immunostaining profile highlights areas suspicious for viable tumor cells by using pan-keratin, CK8/18, EMA, CA9 and CD10. Focal positivity in the same area is noted by the stains of PAX 8 and AMACR. However, with numerous histiocytes, it is difficult to determine if the tumor cells are positive for Vimentin. Moreover CD 117 is negative in the tumor cells. Results (if a Case Study enter NA) NA Conclusion Differential diagnosis includes renal cell carcinoma and xanthogranulomatous pyelonephritis. The overall findings support a clear cell RCC affected by the immunotherapy. With immunotherapy-based combinations becoming standard of care in advanced malignancies, it makes the pathological diagnosis more challenging and difficult, especially for incidental tumors.

Characterization of A Rare Case of Vulvar Epithelioid Sarcoma with local recurrence and metastases

Introduction/Objective Epithelioid sarcoma (ES) is a rare, malignant mesenchymal neoplasm that has a known tendency for local recurrence, regional lymph node involvement, and distant metastases. Two histologic variants have been recognized: classic ES also known as the distal type, and proximal-type ES (PES). The classic ES is common in young adults. It occurs more frequently in the distal upper extremities followed by the distal lower limbs and has a male prevalence of 2:1. Conversely, PES commonly involves deep tissues in the pelvic region, including the genital area. It tends to occur in older patients and follows a more aggressive clinical course. In the female genital tract, PES occurs most frequently in the vulva. The incidence of primary sarcoma of the vulva accounts for 1.5-5% of all malignant tumors, making PES a very rare incidence. Methods/Case Report Here we report a 60-year-old female diagnosed with vulvar epithelioid sarcoma treated with a right radical vulvectomy and bilateral inguinal lymph node dissection in 2008. In 2017, further surgery and adjuvant radiation were given for local recurrence. In 2020, the patient developed left hip pain and was found to have an expansile lytic lesion in the left proximal femur. Extensive resection was performed. Grossly the vulvar lesion was nodular with diffuse hemorrhage, degeneration, and necrosis. Microscopically, the tumor cells had large vesicular nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. Histologically, the morphology of the tumor cells are similar for the primary vulvar specimen and the bone metastases. Immunohistochemically, the tumor cells are positive for vimentin, GATA, FLI-1, SMA, SMHC, partially positive for CAM5.2, AE1/AE3, CD31, and CD163. Immunohistochemistry was negative for CDX2, CD56, S-100, TTF-1, CK5/6, CK20, P40, mammoglobin, MOC31, ER, CK7, CK903, HMB45, PAX8. A Ki-67 proliferative index was around 30-40%. NGS molecular testing detected a SMARCB1 mutation with loss of exons 1-3 and exons 7-9 supporting the diagnosis of epithelioid sarcoma. Results (if a Case Study enter NA) NA Conclusion In summary, we report a case of PES of the vulva in a 60 year old female. Grossly, the lesion was nodular with histology showing large vesicular nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm. It showed loss of INI1/SMARCB1 nuclear expression. The patient is receiving further adjuvant treatment and shows no new metastases.