Hypercalcemia and local production of parathyroid hormone-related protein by a perisellar rhabdomyosarcoma after remote pituitary irradiation.

Objective: To describe a case of metastatic rhabdomyosarcoma originating from the sphenoid sinus in a patient previously treated with conventional irradiation for a prolactinoma, presenting as hypercalcemia in the setting of a normal level of serum parathyroid hormone-related protein (PTHrP).

Methods: We report the case of a patient who underwent remote pituitary irradiation for a prolactinoma and then presented decades later with hypercalcemia of unknown cause. His clinical course, the initial biochemical and radiologic investigations, and the results of examination of pathology specimens are reviewed.

Use of novel immunohistochemical markers expressed in colonic adenocarcinoma to distinguish primary ovarian tumors from metastatic colorectal carcinoma.

Distinguishing primary ovarian carcinoma, particularly endometrioid and mucinous subtypes, from metastatic colorectal carcinoma to the ovary is often difficult on histologic examination alone. Recently, three immunohistochemical markers CDX2, a homeobox gene encoding an intestine-specific transcription factor; alpha-methylacyl-CoA racemase (AMACR/P504S), a mitochondrial and peroxisomal enzyme with fairly restricted expression in selective tumors and beta-catenin, an adenomatous polyposis coli (APC) mutation product resulting in activation of the Wnt pathway, have been reported to have specific and sensitive expression in colorectal carcinomas. We evaluated a panel consisting of antibodies to CDX2, beta-catenin and P504S in 23 primary ovarian adenocarcinomas (13 mucinous and 10 endometrioid) and compared the findings to 22 metastatic colorectal adenocarcinomas (seven mucinous and 15 nonmucinous tumors with endometrioid-like morphology hereafter referred to as pseudo-endometrioid) to the ovary stained with the same panel.