[TSH-secreting fibrous pituitary adenoma showing calcification: a case report]

TSH-secreting pituitary adenoma with calcification and proliferation of the collagen fibers was presented. A 42-year-old man had shown general fatigue and thyroid hypertrophy caused by hyperthyroidism for 3 years. CT and MRI revealed pituitary adenoma with calcification extending into the cavernous sinus and sphenoid sinus. The patient was operated on using the transsphenoidal route twice, but the tumor was not able to be removed totally, partly due to the hardness of the tumor. The tumor in- and around the left cavernous sinus as well as the hardest part of the tumor itself due to the calcification could not be removed. Histopathological examination revealed chromophobe adenoma with proliferation of the collagen fibers. Immunohistological and electronmicroscopic examination demonstrated TSH-secreting adenoma. Postoperatively, thyroid function improved and the patient's symptoms due to hyperthyroidism disappeared.