[The two cases of carotid body tumor in the same family].

Carotid body tumor is a rare neoplasm, occasionally familial in occurence, is difficult to establish its malignancy histopathologically. In this paper, we report two cases seen in the same family. As far as our survey concerned present report on the familial incidence is the second in Japan. Case 1: I. K., 13 years old girl. She visited a hospital with complaints of the neck mass and low grade fever in Oct. 1985. Open biopsy of the neck mass was performed and the histopathological diagnosis was chemodectoma originated from the carotid body. She was referred to the ENT department of Kitasato University Hospital in Jan. 1986. Our initial impression was that the tumor was so large that in order to remove the tumor completely, it was neccessary to make a by-pass of the carotid artery, and the aurgery was deferred until her grow-up completed. Operation was done in May 1987, because the tumor began to grow rapidly. During operation, the electro-encephalogram was monitored and the by-pass of the carotid artery by using the