ISUP Group 4 – a Homogenous Group of Prostate Cancers?

• Published in: Pathology oncology research Vol. 24; no. 4; pp. 921 - 925
• Main Authors: Lu, Thomas Chengxuan, Moretti, Kim, Beckmann, Kerri, Cohen, Penelope, O’Callaghan, Michael
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-10-2018; Springer Nature B.V
• Subjects: Aged; Biomedical and Life Sciences; Biomedicine; Biopsy; Cancer Research; Health risk assessment; Health risks; Heterogeneity; Humans; Immunology; Male; Metastases; Middle Aged; Mortality; Neoplasm Grading - methods; Neoplasm Grading - standards; Oncology; Pathology; Proportional Hazards Models; Prostate cancer; Prostatic Neoplasms - classification; Prostatic Neoplasms - mortality; Prostatic Neoplasms - pathology; Risk analysis; Short Communication; Statistical analysis; Gleason score; Biopsy; Prostate cancer specific mortality; Prostate cancer; Grade group 4
• ISSN: 1219-4956; 1532-2807
• DOI: 10.1007/s12253-017-0331-2

The International Society of Urological Pathology (ISUP) and the World Health Organisation have adopted a five-tiered prognostic grade group for prostate cancer in 2014. Grade group 4 is comprised of Gleason patterns 4 + 4, 3 + 5 and 5 + 3. Recent articles have suggested heterogeneity in their prognostic outcomes. We aimed to determine whether there was a difference in mortality outcomes within the ISUP 4 grouping, as identified on needle biopsy. A total of 4080 men who were diagnosed with non-metastatic (N0 M0) prostate cancer on biopsy with Gleason scores of 7, 8 and 9 were included. Multi-variable Cox Regression and Fine and Grey competing risk analysis were used to determine the All-Cause Mortality (ACM) and the Prostate Cancer Specific Mortality (PCSM) as a function of Gleason Scores (Gleason 3 + 4, 4 + 3, 4 + 4, 3 + 5/5 + 3, 9). Gleason score 4 + 4 was utilized as the referent. The 60 months’ prostate cancer specific mortality with Gleason patterns 4 + 4 and 3 + 5/5 + 3 were 17% and 20% respectively (
P
 < 0.01). Patients with 3 + 5/5 + 3 disease, had no statistically significant difference in the ACM (adjusted hazard ratio [aHR] 0.99, 95% confidence interval [Cl] 0.68–1.4,
p
 = 0.99) and PCSM risk (aHR 0.77, 95% Cl 0.47–1.2,
p
 = 0.31) when compare with the referent group of patients. Patients with Gleason patterns 4 + 3 and 9 had statistically significant difference in their PCSM risk (aHR 0.70, 95% CI 0.54–0.91,
P
 < 0.001 and aHR 1.5, 95% Cl 1.2–1.9, P < 0.001) when compared to the referent group. Our analysis suggest that ISUP group 4 is homogenous in terms of the all-cause mortality and the prostate cancer specific morality risk as differentiated by the presence of Gleason 5 score.