Primary genitourinary melanoma accounts for less than one per cent of all cases of melanoma. Most cases attributed to the prostate actually originate from the prostatic urethra. Due to its infrequency, primary malignant melanoma of the genitourinary tract presents a difficult diagnostic and management challenge. We report a case of primary malignant melanoma of the prostate found during transurethral resection of the prostate.

Background: Cancers of the male urethra constitute less than 1% of all malignant urological tumours, and the occurrence of sarcomas in the urethra is even less frequent. To our knowledge, only one case has been previously described in the English literature.

Urinary bladder pheochromocytoma is rare. From a case report of unsuspected pheochromocytoma and literature review, the authors develop a diagnostic and therapeutic algorithm for the management of this ectopic pheochromocytoma localization.

Most tumors affecting Vater's ampulla are adenocarcinomas, and other histological variants are less frequent. Signet ring cell carcinoma is more commonly found in the stomach than at other sites of the digestive system. Signet ring cell carcinoma of the Vater's ampulla is extremely rare, and only 15 cases have previously been described in the literature. It mainly occurs in elderly patients (median age = 57 years). We report a case of advanced signet ring cell carcinoma of the ampulla of Vater, with invasion of the duodenum (D3) admitted in the Medical Oncology Unit of HASSAN II University Hospital.

Granular cell tumor (GCT) was first described by Abrikossof in 1926. This tumor is a benign neoplasm of unclear histogenesis that is generally believed to be of nerve sheath origin. GCT is not common and most often affects the tongue, skin, and soft tissue, although it may occur anywhere in the body. Gastrointestinal tract involvement, and especially that of the colon, is very rare. This usually benign tumor appears as a submucosal nodule, measuring less than 2 cm in diameter and is often found incidentally during colorectal examinations. We describe the case of a 27-year-old man with a GCT in the cecum that was detected after a screening colonoscopy. Endoscopic examination revealed a yellowish submucosal tumor, 0.7 cm in diameter. An endoscopic mucosal polypectomy was done for histological confirmation and treatment.