Pathological changes after radiotherapy for primary pituitary carcinoma: a case report.

Pituitary carcinomas are extremely rare. The definition, diagnosis, therapy, and prognosis are controversial. So far, to our knowledge, there has been no report regarding pathological changes after radiotherapy for primary pituitary carcinoma. We reported a single case of a presumed prolactin staining pituitary carcinoma. We defined carcinoma by premorbid intracranial dissemination of the tumor. There were no proven extracranial metastases. The tumor was silent on PET scanning. The patient received external beam radiotherapy alone as primary therapy. Post-irradiation histology revealed that necrotic tissue made up approximately more than half. Tumor had viable cells. Probably approximately three-fifth of tumor cells were without alteration and approximately two-fifth were with degeneration. We confirmed that necrosis but no apoptosis were coexistent in the cells post irradiation for pituitary carcinoma.