Significance of capsular attachment and invasion of cancer tissues in prostate cancer

Background: There is a discrepancy in tumor node metastasis (TNM) staging of capsular attachment and invasion; the condition was classified as pT3 in 1987, then as pT2 in 1992. Because capsular finding associated with radical prostatectomy is an important prognostic factor, the present study was conducted to characterize clinicopathological states of cancer tissues attached to and invading the capsule. Methods: Specimens removed by radical prostatectomy exhibiting pT2 or pT3 from 90 patients who did not receive any treatment before surgery were classified as Loc (24%, cancer tissues localized and apart from capsule), Inv (59%, attached to and invading but not penetrating capsule) and Pen (17%, penetrating capsule). Their clinicopathological profiles were examined. Results: Gleason score, volume of cancer tissues, seminal vesicle invasion, positive surgical margin and regional lymph node metastasis of Inv were distributed between those of Loc and Pen. Postoperative management was decided as routine check-up or endocrine therapy according to pathological findings. Median follow-up was 59 months. Prostate-specific antigen (PSA) relapse occurred in 13 patients, one of whom died of prostate cancer. The remaining of these patients lived. Rate of PSA relapse was not different between Loc and Inv, mainly due to endocrine therapy to Inv with high risk factors. Conclusion: Pathological profile of Inv lies between those of Loc and Pen. Therefore, pT2a (1997) would be subclassified as Loc and Inv. Patients with Inv may be required to receive the respective management according to clinicopathological profile, which would be different to that of Loc.