title: Carcinoid tumor of the renal pelvis: consideration on the histogenesis.
abstract: Carcinoid tumor of the renal pelvis is an extremely rare neoplasm and only two cases have been previously reported in the English-language literature. Reported herein is a third case of carcinoid tumor arising in the renal pelvis. The tumor extending from the left renal pelvis into the left kidney was incidentally found in a 55-year-old Japanese woman. Macroscopically, the tumor was predominantly located in the dilated renal pelvis and was grayish-white on cut surface. Microscopically, neoplastic cells proliferated with a ribbon-like, trabecular, tubular and solid pattern. Furthermore, the tumor focally invaded the kidney parenchyma. No precursor lesion of neuroendocrine tumor was observed in the peripheral urothelial epithelium. Neither urothelial carcinoma nor teratoma component was observed within the tumorous mass. The cytoplasm of neoplastic cells was focally positive for Grimelius stain and focally positive for chromogranin A and synaptophysin. However, no neoplastic cells reacted with cytokeratins 7 and 20. Ultrastructurally, neoplastic cells contained dense core granules in the cytoplasm. Urologists and pathologists should recognize that carcinoid tumor may arise from the renal pelvis.
authors: Department of Diagnostic Pathology, Kochi Red Cross Hospital, Kochi City, Japan. nkurodakrch@yahoo.co.jp
authors: Naoto
authors: N
authors: Kuroda
authors: Kazunobu
authors: K
authors: Katto
authors: Masato
authors: M
authors: Tamura
authors: Tomoyuki
authors: T
authors: Shiotsu
authors: Ondrej
authors: O
authors: Hes
authors: Michal
authors: M
authors: Michal
authors: Yoji
authors: Y
authors: Nagashima
authors: Masahiko
authors: M
authors: Ohara
authors: Takashi
authors: T
authors: Hirouchi
authors: Keiko
authors: K
authors: Mizuno
authors: Yoshihiro
authors: Y
authors: Hayashi
authors: Gang-Hong
authors: GH
authors: Lee
mesh_terms: D002276:Carcinoid Tumor / Q000378:metabolism / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000378:metabolism / Q000648:ultrastructure*; D007682:Kidney Pelvis / Q000378:metabolism / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged