High-grade inflammation in prostate cancer as a prognostic factor for biochemical recurrence after radical prostatectomy

Abstract

Objectives. To assess the prognostic value of prostatic stromal inflammation in surgically treated localized prostate carcinoma for biochemical recurrence-free survival. Methods. Stromal prostatic inflammation grading was studied in 161 patients who underwent radical prostatectomy for prostate cancer without involvement of the lymph nodes and who did not receive preoperative or postoperative radiotherapy or hormonal therapy until recurrence occurred. Inflammation was graded as high-grade inflammation if confluence of inflammatory cell infiltrate and/or glandular epithelium disruption associated with interstitial inflammatory infiltrate were present and as low-grade inflammation otherwise. Each specimen was graded separately first in the stroma surrounding nonmalignant glands and second in the stroma surrounding malignant glands. Biochemical recurrence based on serum prostate-specific antigen (PSA) level was defined as two successive PSA measurements greater than 1 ng/mL. Results. Malignant tissue was significantly less involved in high-grade inflammation than benign adjacent tissue (9.3% and 19.9%, respectively; P <0.01). In a univariate Kaplan-Meier analysis, the 5-year recurrence-free survival rate for patients with high-grade and low-grade classified prostates was 61.0% and 66.7% in benign tissue and 27.0% and 65.3% in malignant tissue, respectively, with a significant difference between grades only in malignant tissue ( P <0.02). In a multivariate analysis controlling for Gleason grade, preoperative serum PSA, pathologic stage, and inflammation grade in malignant tissue, the latter factor remained significantly predictive of biochemical recurrence ( P = 0.03). Conclusions. Patients with high-grade inflammation surrounding malignant glands in radical prostatectomy specimens had significantly more postoperative biochemical recurrence than patients with low-grade inflammation.