Pituitary metastases: current practice in Japan

With advancement of cancer treatment and development of neuroimaging techniques, contemporary clinical pictures of pituitary metastases (PMs) must have changed from past reports. The goal of this paper was to elucidate the clinical features of PMs and current clinical practice related to those lesions. In this retrospective study, questionnaires were sent to 87 physicians who had treated PMs in Japan. Between 1995 and 2010, 201 patients with PMs were treated by the participating physicians. The diagnosis of PM was histologically verified in 69 patients (34.3%). In the other 132 patients (65.7%), the PM was diagnosed by their physicians based on neuroimaging findings and clinical courses. The most frequent primary tumor was lung (36.8%), followed by breast (22.9%) and kidney (7.0%) cancer. The average interval between diagnosis of primary cancer and detection of PM was 2.8 ± 3.9 (SD) years. Major symptoms at diagnosis were visual disturbance in 30.3%, diabetes insipidus in 27.4%, fatigue in 25.4%, headache in 20.4%, and double vision in 17.4%. Major neuroimaging features were mass lesion in the pituitary stalk (63.3%), constriction of tumor at the diaphragmatic hiatus (44.7%), hypothalamic mass lesion (17.4%), and hyperintensity in the optic tract (11.4%). Surgical treatment was performed in 26.9% of patients, and 74.6% had radiation therapy; 80.0% of patients who underwent radiotherapy had stereotactic radiotherapy. The median survival time was 12.9 months in total. Contributing factors for good prognosis calculated by Cox proportional hazard analysis were younger age, late metastasis to the pituitary gland, smaller PM size, and radiation therapy. The Kaplan-Meier survival was significantly better in patients with breast cancer and renal cell cancer than in those with lung cancer. At the time of this writing, approximately 60% (120/201) of PMs had been treated by stereotactic radiation therapy in Japan. The median survival time was much longer than that reported in past series. To confirm the changes of clinical features and medical practice, a prospective and population-based survey is mandatory.