Purpose: The Grade Group (GG) classification is recommended by guidelines as a reliable prognostic factor of prostate cancer. However, most studies have been performed on the Caucasian population. Our objective was to validate GG classification as a safe way to classify intermediate- and high-risk patients with African ancestry.
Patients and methods: This was a retrospective study in an Afro-Caribbean population. A total of 1236 patients were included between 2000 and 2015. Patients were stratified according to (GG). Survival analysis was performed using the Kaplan-Meier method, univariate and multivariate analyses using the Cox model.
Results: There was no significant difference at 5 and 10-year BCR-free survival between the intermediate- and high-risk groups, based on the D'Amico classification. There was a highly significant difference in BCR-free survival at 5 (p < 0.0001) and 10 years (p < 0.0001) for patients of GG 1 and 2 vs 3, 4, and 5, respectively. There was no significant difference in 5-year BCR-free survival of patients of GG grades 1 and 2, whether lymph-node dissection was performed or not. There was a significant difference between GG 2 and 3 patients in 5 (p = 0.008) and 10-year BCR-free survival (p = 0.01). High PSA (p < 0.0001), pathological GG ≥ 3 (p < 0.0001), pathological stage pT3 (p < 0.0001) and positive margins (p < 0.0001) were factors for BCR in multivariate analysis.
Conclusion: The GG 2015 classification appears to be a better prognostic factor than D'Amico classification for intermediate- and high-risk Afro-Caribbean patients.
Keywords: Afro-Caribbean; Biochemical recurrence; Grade Group; ISUP classification; Prostate cancer.