The pathological and clinical features of anterior lesions of prostate cancer: Evaluation in a single cohort of patients

Introduction. The aim of our work is to evaluate the principal differences of the pathological features in prostate cancer (PCa) lesions comparing those in the anterior region of the gland (APCa) to those in the posterior zone (PPCa) among patients who underwent to robotic-assisted radical prostatectomy (RP).
Material and methods. A total of 85 consecutive patients (mean age 66; IQR 62-71) with clinically suspected PCa were studied with multiparametric magnetic resonance of prostate before prostate biopsies. The prostate biopsies were RM-guided (60 inbore biopsy (MR-GB) and 25 Fusion-biopsy (FB). A total of 72 cases were eligible for robotic RP. An experienced genitourinary pathologist reviewed the histopathology of the tissue specimens of the patients after RP. The exclusion criteria were as follows: previous hormonotherapy, radiotherapy and chemotherapy for others cancers.
Results. Based on the histological diagnosis, after RP, 68 anterior prostate cancer, and 107 posterior lesions were found. We further subcategorized lesions into peripheral and central zones for each the anterior and posterior lesions. The specific distribution of lesions by pathologic stage was: T2 = 74 (42.3%), T3a = 87 (49.7%), T3b = 12 (6.9%), T4 = 2 (1.1%) cases. Tumor volume of posterior neoplasms ranged from 0.04 to 20.35 cm3, with a median of 3.39 cm3. Anterior tumor volume ranged from 0.17 to 15 cm3, with a median volume of 2.54 cm3: PPCa were larger than APCa but the difference in size was not significant. The prostate cancer grade group (GG) I was distributed as 16.6% and 36% in anterior and posterior lesions cases. GG II and III was 43.8% and 31.5% in anterior and posterior cases, respectively. Comparatively, GG IV-V showed 39.6% and 32.5% for anterior and posterior lesions respectively (p < 0.001). Extraprostatic extention of neoplasm (EPE) was found more frequently in anterior cases (31.4%) than in in posterior cases (25.1%), but without significant difference. Lymphovascular invasion was similar in both the groups: 24% and 28.6% in anterior and posterior group, respectively. Anterior lesions showed a significantly higher rate of lymph node metastasis (9.3%) than posterior lesions (3.4%) (p < 0.005).
Conclusion. In our study, we have found EPE, often associated with worse prognosis, more frequently (but not significantly) present in anterior lesions among PCa patients. Although posterior lesions are often related to pT3b stage, in our findings, anterior lesions were more often associated with a more aggressive neoplasm with more frequent nodal involvements.