Do the results of systematic biopsies predict outcome in patients with T1-T2 prostate cancer treated with radiation therapy alone?

Contemporary pathology of prostate cancer

In less than 20 years since the introduction of serum PSA and the spring-loaded 18-gauge prostatic biopsy needle, pathologists have adjusted to the limited tissue requirements of narrow needle specimens to apply criteria for diagnosis and grading of prostate cancer, borrowing from lessons learned from radical prostatectomies. Substantial gains have been made during this period in the understanding of precancerous lesions, mimics of malignancy, the criteria for minimal cancer, variants of cancer, and treatment-induced changes. The light microscopic findings remain the criterion standard for diagnosis against which all new techniques should be measured. Numerous findings have proven to be of value, including simple quantitation of histopathologic features, cancer volume, perineural invasion, and others.

Pathologic features from prostate needle biopsy and prognosis after I-125 brachytherapy

To evaluate the role of detailed pathologic features in predicting outcome for early-stage prostate cancer treated with I-125 brachytherapy. The pretreatment biopsy slides of 103 patients with T1/T2 and Gleason scores of 4-7 prostatic carcinoma, which was treated by transperineal I-125 implantation, were reviewed retrospectively by a single pathologist (P.B.G.). Biochemical tumor control rates [prostate-specific antigen (PSA) below 1.0] were correlated with pretreatment PSA, Gleason score, the amount of tumor in the biopsy samples, and the presence of perineural invasion. In Cox proportional-hazard, multivariate analysis, the strongest predictors of failure were pretreatment PSA above 10 ng/ml (P = 0.013) and the length of the biopsy specimen replaced by tumor (P = 0.15). The percent of biopsy tissue replaced by tumor (P = 0. 74), perineural invasion (P = 0.78), and Gleason score (P = 0.66) were less predictive of prognosis. It was concluded that pretreatment PSA is the strongest predictor of biochemical failure. Detailed assessment of pathological features on needle biopsy added little prognostic information beyond that of pretreatment PSA alone. Like all other prognostic parameters for prostate cancer, there is considerable overlap in pathologic features between those patients who will or will not be controlled biochemically.