Abstract and Introduction
Abstract
The clinical significance of atypical glands suspicious for malignancy (atypia) on prostate biopsy is unclear. We studied a cohort of 139 patients with atypia who underwent repeat prostate biopsy. We analyzed clinical and pathological variables that may be associated with cancer on repeat biopsy. Cancer was diagnosed in 41 (29%) of patients with atypia: 26 of 41 (66%) were Gleason 6, 20% were Gleason 7 and 7% were Gleason 8 (Gleason <6 not reported). There were no significant associations of age, race, family history, PSA, PSA density (PSAd), number of previous biopsies or time to repeat biopsy with cancer diagnosis. In multivariate regression, histological inflammation was associated with an 85% decreased probability of cancer on repeat biopsy (odds ratio; OR 0.15; 95% confidence interval; CI 0.04–0.57; P=0.04). Radical prostatectomy was performed in 14 of 41 (34%) patients with cancer; 6 (43%) were Gleason sum ≥7, 3 (21%) were pT3a and 1 (7%) had lymph node metastases. In conclusion, inflammation was independently associated with a significantly decreased risk of cancer on repeat biopsy. However, some patients with initial atypia have higher-risk prostate cancer. Additional studies are needed to elucidate these associations.
Introduction
Atypical glands suspicious for malignancy (atypia) are a relatively common pathological finding on prostate biopsy. Also called atypical small acinar proliferation, atypia is a term for small foci that are suspicious for, but not diagnostic of, adenocarcinoma. The prevalence of atypia on initial prostate biopsy is ~5%. Prostate cancer screening has led to roughly 1 000 000 prostate biopsies yearly in the United States of America. Based on a 5% prevalence of atypia, it is estimated that 50 000 new cases will be diagnosed yearly, each of which will require a repeat biopsy to evaluate for malignancy. Although there is ~40% probability of detecting cancer on repeat biopsy for atypia, cancer prevalence varies widely from one study population to another: 17–70%. Potential explanations for this variation include small sample sizes, variable biopsy schema, diagnostic biases and disparate patient populations.
Current recommendations are that, because of the relatively high probability of cancer, repeat biopsy is indicated after diagnosis of atypia. However, clinical and pathological variables associated with diagnosis of cancer on repeat biopsy for atypia have not been defined. Further investigation of these variables may elucidate connections of atypia with cancer diagnosis and thus lead to refinements in clinical care. We investigated the clinical and pathological characteristics of patients who underwent repeat biopsy for atypia found on initial prostate biopsy, analyzed variables associated with cancer on repeat biopsy and reviewed the pathological findings of patients who underwent prostatectomy.