[Indolent T-lymphoblastic proliferation in association with localized Castleman disease: A case report]. / Maladie de Castleman localisée avec prolifération lymphoblastique T indolente.

Herein we report the case of a 41-year-old woman who presented with pelvic pain. Magnetic Resonance Imaging exhibited a single pelvic mass, measuring 50mm long axis, alongside the right iliac vessels. Histological examination of the excision specimen showed a lymphoid tumor with features of localized Castleman disease, hyaline vascular type. Moreover we identified multiple interfollicular dark clusters, composed of cells morphologically resembling cortical thymocytes. Their immunophenotype was consistent with an intermediate stage of T-cell differentiation, with the expression of CD3, CD4, CD8, TdT, CD1a, CD99, CD2, CD5, CD7 and CD10, with 40% Ki67. After integration of clinical and molecular data, the retained diagnosis was an indolent T-cell lymphoblastic proliferation associated with hyaline vascular localized Castleman disease. The clinical course confirmed the indolent nature of the proliferation, despite a late local recurrence at 7 years of the initial diagnosis, without histological modification, due to an incomplete initial resection surgery.

[Medullomyoblastoma: a medulloblastoma with rhabdomyoblastic differentiation]. / Le médullomyoblastome : une variante de médulloblastome avec différenciation rhabdomyoblastique.

A 26 years old patient was operated for a tumor of cerebellar vermix, and then reoperated for a relapse at the age of 35 years, with a similar histological pattern in both cases. At pathologic examination, the tumor was composed of hypercellular sheets typical of medulloblastoma, containing also sparse large cells with eosinophilic cytoplasm and round nuclei containing voluminous nucleoli. Neuroblastic cells showed expression of neurofilament protein and synaptophysin. The large cells expressed desmin, myogenin, and neurofilament. These morphological and immunohistochemical features are characteristic of medullomyoblastoma. The patient deceased 11 years after the initial surgery. Medullomyoblastoma is a rare variant of medulloblastoma with a rhabdomyoblastic differentiation. The two tumoral populations share the same genetic alterations. The main differential diagnoses are atypical teratoid/rhabdoid tumor, immature teratoma, medulloepithelioma, primitive intracranial rhabdomyosarcoma and myoneurocytoma.

Primary malignant esophageal melanoma arising from localized benign melanocytosis.

A heavy drinker and smoker had a normal UGI-endoscopy in 1996. In 1999, a repeat examination disclosed distal esophageal benign melanocytosis, typical, macro- and microscopically. Endoscopic and microscopic features were stable in 2002 and 2004. In 2007, dysphagia prompted an endoscopy, which disclosed a poorly differentiated epidermoid carcinoma at 19 cm and black nodules of the cardia with a microscopy typical of malignant melanoma, uT3N1 at EUS. Radiochemotherapy led to an 8-month improvement, which did not prevent death one year after diagnosis.