Long-term follow-up of conservatively managed incidental carcinoma of the prostate A multivariate analysis of prognostic factors

Abstract

Objective. To evaluate the disease-specific mortality of conservatively managed incidental carcinoma of the prostate (T1a and T1b) in relation to prognostic factors. Material and methods. Since 1987 all patients with prostate cancer have been recorded and followed in the population-based Prostate Cancer Register of the South-East Healthcare Region in Sweden, which is covered by four departments of pathology. At two of these departments, tissue was obtained from 197 consecutive, previously untreated patients (aged <80 years) with incidental carcinoma who underwent transurethral resection of the prostate between 1987 and 1991. The amount of tumour, Gleason score and levels of Ki-67, p53, chromogranin A and serotonin were determined. Univariate analysis and multiple Cox regression hazard analysis were used for analysis. Results. During follow-up (mean 7.8 years; maximum 17.5 years), 158 patients (80%) had died, 33 of them of prostate cancer, corresponding to 17% of the entire cohort. Of 86 patients with Gleason score ≤5, three died of prostate cancer. Independent predictors of disease-specific mortality in multivariate analysis were category T1b prostate cancer, Gleason score >5 and high immunoreactivity of Ki-67. Conclusions. Elderly men with category T1a and/or Gleason score 4–5 prostate cancer have a favourable prognosis with conservative management. Immunohistochemical staining with Ki-67 may be of help in situations where further prognostic information is required.

• Prostate cancer
• prognostic factors
• incidental carcinoma
• survival
• p53
• Ki-67
• chromogranin A