Y/6 chromosome translocation in a male with triple primary cancers involving the breast.

Cytogenic studies were performed in a 72-year-old male patient with triple primary cancers including breast, skin and lung. Left breast cancer was diagnosed at the age of 46 and he received mastectomy and thoracic irradiation. Squamous cell carcinoma and Bowen's disease were diagnosed from two separated parts of a skin lesion at the age of 70. Small-cell lung cancer was diagnosed 1 year later, and he received chemotherapy and radiotherapy. Chromosome analysis was carried out on both peripheral lymphocyte and skin fibroblast cultures at the age of 72. Out of 30 fibroblast cells karyotyped at the second passage, 7 cells (23%) consistently showed a reciprocal translocation t(Y;6)(q12;p21). The same translocation was found in one of 200 cells from lymphocyte cultures. The findings suggest that the translocation t(Y;6) might be inherent in nature, and that the patient was a mosaic of 46,XY/46,X,t(Y;6)(q12;p21). These results highlight the constitutional chromosomal abnormality as one of the possible high-risk factors for multiple primary cancers.