The role of high-grade prostatic intraepithelial neoplasia for biochemical relapse of prostate carcinoma after radical prostatectomy

The objective of the study was to evaluate the relationship between high-grade intraepithelial neoplasia diagnosed after radical retropubic prostatectomy and the clinical and pathological characteristics of prostate cancer, and to evaluate the time to biochemical relapse of the disease within the groups of high-grade prostatic intraepithelial neoplasia (HGPIN) and non-HGPIN patients.
Material and methods. Patients, clinically diagnosed with local prostate carcinoma at the Clinic of Urology, Kaunas University of Medicine, during 2003–2007 and treated with radical retropubic prostatectomies, were distributed into two groups according to the HGPIN detected in the postoperative material: HGPIN and non-HGPIN. The two groups were compared in terms of preoperative and postoperative characteristics. The patients who were followed up for at least 12 months were included into the study. The biochemical relapse of prostate cancer was determined if there were two consecutive rises of prostate-specific antigen (PSA) level above 0.2 ng/mL or according to the attending physician’s opinion, there was a need for adjuvant treatment even with onetime rise of PSA level above 0.2 ng/mL.
Results. There was no significant difference between the HGPIN and non-HGPIN groups in terms of time to biochemical relapse and frequency of biochemical relapses, time before surgery, the timing of the HGPIN diagnosis, age, or PSA level. After radical prostatectomy, patients in the HGPIN group were found to have significantly more often poorer cancer cell differentiation according to the Gleason score (≥7 vs. <7; P=0.001) and higher TNM stage (T3a,b vs. T2a,b,c; P=0.001). Fewer positive resection margins were diagnosed in the HGPIN group (P=0.05). The groups did not differ in terms of the degree of differentiation according to the Gleason score or perineural invasion (P=0.811 and P=0.282, respectively).
Conclusions. HGPIN was more often associated with the characteristics of the poor prognosis for relapse of prostate cancer: poorer tumor cell differentiation according to the Gleason score and more cases of higher TNM stage. HGPIN did not have any influence on biochemical relapse of the disease during the short-term follow-up.