MICROSATELLITE INSTABILITY IN PROSTATE-CANCER

Assessment of the genetic instability of a microsatellite has indicate d a new mechanism in human carcinogenesis. Examination was made to det ermine whether microsatellite instability is associated with the onset of prostate cancer. Twenty-nine DNA samples from 24 primary prostate cancer, two metastatic lymph-node and three benign prostatic hypertrop hy patients were used. Differences in unrelated microsatellites for tu mor and normal DNA were detected in nine of 24 (37.5%) cases. Seven of 11 (63.6%) with poorly differentiated adenocarcinomas and seven of 15 (46.7%) stage D metastatic patients showed somatic instability in a n umber of microsatellites. Statistically significant differences in wel l to moderately differentiated tumors and poorly differentiated cancer (P=0.015, Chi-square test), were detected but not for stages A-C and D (P=0.2311). Genetic alterations would thus appear to be rare in low grade and/or early prostate cancers but more common in high grade and/ or advanced prostate cancers.