[A case of occult breast carcinoma with micronodular shadows on chest x-ray film].

A 57-year-old woman was admitted to our hospital for the evaluation of roentgenological micronodular shadows of the bilateral middle and lower lung fields. Physical findings were normal except for left axillary lymph adenopathy. The level of tumor marker NCC-ST-439 was markedly elevated (2800 U/ml). Histological examination of the transbronchial biopsy and the swollen lymph node biopsy specimens showed proliferation of identical tumor cells. Breast or lung carcinoma was suspected as the primary site. Echogram of the left breast showed microcalcification without a mass. The biopsy specimen obtained from the calcified lesion indicated occult breast carcinoma. From these findings the diffuse micronodular shadows on the chest roentgenogram were considered to be the metastatic lesions of occult breast carcinoma. This case indicates that occult breast carcinoma should be considered as a possible primary site for diffuse pulmonary metastatic lesions.