Primary vulval rhabdoid tumor in an adult: a case report, immunohistochemical profile and literature review

Extrarenal rhabdoid tumour of the vulva: diagnostic and management challenges

Extrarenal rhabdoid tumour (ERT) of vulva is a rare gynaecological neoplasm with an aggressive course and no clear management guidelines. We present the case of a 25-year-old woman with a rapidly increasing mass in right vulva suggestive of sarcoma. Wide local excision was done. Histopathology examination revealed ERT of vulva. Six weeks later she manifested lung metastases. Despite adjuvant chemotherapy, the disease progressed and she died 8 months later. We review the literature and briefly discuss the epidemiology, treatment approaches, prognostic factors and expected outcomes of this rare disease.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Finding in a Rare Case of Follicular Carcinoma of Thyroid with Rhabdoid Morphology

Rhabdoid tumor commonly occurs in the kidney and has an aggressive clinical course with high mortality. Extrarenal rhabdoid tumours can involve a number of organs, but poorly differentiated follicular carcinoma with rhabdoid phenotype is an extremely rare clinical entity. The 18F-FDG PET feature of this thyroid malignancy is not available in the literature to the best of our knowledge. But, this feature has significant clinical relevance in management of such patients. We present such a case.

Embryonic signature distinguishes pediatric and adult rhabdoid tumors from other SMARCB1-deficient cancers

Extra-cranial rhabdoid tumors (RT) are highly aggressive malignancies of infancy, characterized by undifferentiated histological features and loss of SMARCB1 expression. The diagnosis is all the more challenging that other poorly differentiated cancers lose SMARCB1 expression, such as epithelioid sarcomas (ES), renal medullary carcinomas (RMC) or undifferentiated chordomas (UC). Moreover, late cases occurring in adults are now increasingly reported, raising the question of differential diagnoses and emphasizing nosological issues. To address this issue, we have analyzed the expression profiles of a training set of 32 SMARCB1-deficient tumors (SDT), with ascertained diagnosis of RT (n = 16, all < 5 years of age), ES (n = 8, all > 10 years of age), UC (n = 3) and RMC (n = 5). As compared with other SDT, RT are characterized by an embryonic signature, and up-regulation of key-actors of de novo DNA methylation processes. Using this signature, we then analysed the expression profiling of 37 SDT to infer the appropriate diagnosis. Thirteen adult onset tumors showed strong similarity with pediatric RT, in spite of older age; by exome sequencing, these tumors also showed genomic features indistinguishable from pediatric RT. In contrary, 8 tumors were reclassified within carcinoma, ES or UC categories, while the remaining could not be related to any of those entities. Our results demonstrate that embryonic signature is shared by all RT, whatever the age at diagnosis; they also illustrate that many adult-onset SDT of ambiguous histological diagnosis are clearly different from RT. Finally, our study paves the way for the routine use of expression-based signatures to give accurate diagnosis of SDT.