Prognostic significance of nucleolar surface area in prostate cancer

In an effort to define ultrastructural histologic features that might serve as predictors of tumor aggressiveness, a retrospective study was conducted on 52 patients with localized and metastatic adenocarcinomas of the prostate. Nucleolar surface area measurements were made by stereologically analyzing pictures obtained by the backscattered electron imaging (BEI) attachment to a scanning electron microscope (SEM). The data were compared with the Gleason grading system which is based on light microscopic glandular patterns. In patients with no evidence of disease three years or more after radical prostatectomy, the initial biopsy demonstrated nucleolar surface areas which averaged 1.28 micrometers2 (range 0.60 to 2.27 micrometers2) whereas, patients with metastases or dying of cancer exhibited an average nucleolar surface area of 5.17 micrometers2 (range 2.49 to 10.01 micrometers2). With a single exception in this 52-patient survey, progressive disease was always accompanied by nucleolar surface measurements larger than 2.40 micrometers2. There was close correlation in nucleolar surface measurements between the initial biopsy and the radical prostatectomy specimens; in contrast, Gleason grades varied by more than 30 per cent between the initial and final specimens in 70 per cent of the cases. Only 9 of 16 patients with aggressive disease ever demonstrated Gleason grades above 6. The development of an ultrastructural grading system may provide a means of determining prognosis in prostatic cancer in objectivity and specificity to light microscopic grading systems.