Allelic losses at 8p, 10q, 11p, 13q, 16q, 17p, and 18q in prostatic carcinomas: The impact of zonal location, Gleason grade, and tumour multifocality

Abstract

Molecular genetic investigations have made it clear that the development and progression of prostate cancer is associated with losses of genetic material in certain chromosomal arms. However, there are only few data about the question of whether the zonal location, a higher Gleason grade, or multifocality of the tumour have any influence on the pattern of allelic losses.

In the present study, 48 tumour foci from 32 radical prostatectomy specimens were investigated for allelic losses at chromosomes 8p, 10q, 11p, 13q, 16q, 17p, and 18q with a set of 20 microsatellite markers. The results were analysed for the zonal location of the tumour foci and the presence of a Gleason grade 4 differentiation.

Overall, focal allelic losses at 8p, 10q, 11p, 13q, 16q, 17p, and 18q were observed in 62.5%, 17.2%,. 3.2%, 18.8%, 40%, 9.7%, and 22.6% of the 32 cases, respectively. Comparing the frequencies of allelic losses with the zonal location or the Gleason grade, no highly significant correlations were found at any chromosomal locus investigated. However, the observation of different patterns of allelic losses in 12 of 14 cases containing more than one tumour focus indicates a high rate of genetic heterogeneity.

We conclude that allelic losses at the chromosomal loci investigated are not strongly associated with a specific zonal location or a higher Gleason grade of prostatic carcinoma. Genetic heterogeneity of multiple tumour foci within one gland might contribute to the difficulties in predicting the prognosis for this common malignancy.