A report on Five Cases of Pulmonary Hamartoma.

Among bebign tumors of lung, pulmonary hamartoma shows a relatively high frequency of appearance, or about 20 per cent. It has been considered, however, to be rather rare, as compared with pulmonary carcinoma. The authors have encounted five cases of pulmonary hamartoma up this time. This paper deals with these cases. The five patients encounted were composed of three males and two females. Of them, one was 16 years old and three were more than 40 years old. Four patients were detected by regular examination. Pulmonary hamartoma occurred in the right lung in three cases, in the left lung in two cases, or in the upper, middle, and lobes in two one, and two cases. Chest X-ray finding revealed that all the lesions were clear in demarcation, round or elliptic in shape, free calcification, and presented homogeneous internal shadows. Surgical operation was performed on all the cases. A segment was excised in three cases and a lobe in one case. Epauxesiectomy was conducred in the other case, since the lesion was directy beneath the the pleura and could be separated from the pulmonary tissue. In excised specimens, the tumor was　1-2 cm in diameter and had no capsule. Its cut surface was grayish white, elastic, and, hard, exhibiting a lobular structure. Histologically, all the cases were diagnosed as cartilaginous hamartoma. Prognosis was good in them. Neither death nor complication pccurred to any case. The tumor has such characer that care should be taken not to excise too large a portion of the lung in order to preserve the pulmonary fuction.