[Malignant peritoneal mesothelioma in a child. Diagnostic difficulties in a locally "non tumoral" form, revealed by cervical lymph node metastasis]. / Mésothéliome malin péritonéal chez un enfant. Difficultés diagnostiques devant une forme localement "non tumorale", à présentation métastatique ganglionnaire cervicale.

We report the unusual case-history of a ten-year-old girl who presented with enlarged cervical and supraclavicular lymph nodes apparently due to sinus histiocytosis upon initial histological evaluation. However, they were shown to be nodal metastases from an epithelial form of malignant mesothelioma coexpressing keratin, vimentin, and desmin. Exploratory laparotomy disclosed a diffuse "non tumoral" peritoneal mesothelioma. The neoplastic cells were so highly differentiated that analysis of peritoneal fluid pointed to reactive mesothelial hyperplasia. Intensive combination chemotherapy failed to achieve complete remission, but the child's condition was satisfactory after two and a half years follow-up. On the basis of data from the literature, we review the course, immunohistochemical features, and differential diagnosis of malignant peritoneal mesothelioma.

[Well differentiated adenocarcinoma ("yellow cancer") of the prostate. Problems of diagnosis and prognosis (author's transl)]. / L'adénocarcinome très différencié ("yellow cancer") de la prostate. Problèmes de diagnostic et de pronostic.

This paper reports the case of a very large hyperdifferentiated prostatic adenocarcinoma, characterized by a very high lipid content; there is little information in the literature about diagnosis and prognosis of this rare type of cancer. Relevant characteristics of this tumor were its middle prostatic location, its soft consistency and its homogeneous yellow appearance (the so called "yellow cancer") - In spite of its large size, the growth remained confined to the prostate. The histological aspect of this cancer is close to intense glandular hyperplasia, so the differential diagnosis is quite difficult on scanty biopsy samples without lipid stains.

[Urothelial bladder carcinoma in situ involving the whole urinary tract. One case (author's transl)]. / Carcinome urothélial in situ étendu à tout l'arbre urinaire. A propos d'un cas.

We report a case of urothelial carcinoma in situ extended to the whole excreto-urinary tract and involving the prostatic gland and the papillary ducts of the kidney. The patient was followed up for almost five years. The evolution was unfavorable, as multifocal invasion appeared. We emphasize the difficulties of the pathological diagnosis on biopsy samples and relate the usual behaviour of this type of cancer who may often simulate an interstitial cystitis. Because of uncertain prognosis and difficulties in the evaluation of the disease, the optimal management for such patients remains imprecise in spite of the benefit of cytologic surveillance. Thus, in the absence of obvious invasion the choice of treatment depends at time on morphological data as well as on topographic and functional criteria.