FREQUENCY OF CHROMOSOME-7 GAIN IN HUMAN BREAST-CANCER CELLS - CORRELATION WITH THE NUMBER OF METASTATIC LYMPH-NODES AND PROGNOSIS

Trisomy 7 has been reported in various malignant neoplasms, but there are no reports in breast cancer. In order to evaluate the contribution of chromosome 7 gain to breast cancer, we investigated the relationsh ip of numerical abberation of chromosome 7 with clinicopathological va riables and prognosis in seventy-nine breast cancer cases (invasive ca rcinomas) using the technique of fluorescence in situ hybridization (F ISH) on paraffin-embedded sections. A significant correlation of the f requency of cells with extra copies of chromosome 7 (percent polysomy 7 cell score) was found with tumor size, regional lymph node status, t nm stage, histological extension, estrogen receptor (ER), and DNA ploi dy. The number of metastatic lymph nodes was positively correlated wit h percent polysomy 7 cell score (correlation coefficient=0.623, p< 0.0 1). Furthermore, cases with a high percent polysomy 7 cell score had a shorter disease-free survival and overall survival times, especially in the lymph node-positive group. It was demonstrated that percent pol ysomy 7 cell value was closely associated with lymph node metastasis a nd prognosis and might be a useful prognostic predictor of breast canc er patients. (C) 1998 Tohoku University Medical Press.