Over-diagnosed prostate cancer in solid organ recipients: lessons from the last 3 decades

Introduction: Prostate cancer (PC) is the most common neoplasia in men. With aging of solid organ transplant recipients (SOTR), its incidence is likely to increase. The aim of this study was to analyze PC screening results retrospectively in renal transplant recipients (RTR), hepatic transplant recipients (HTR) and cardiac transplant recipients (CTR).

Patients and methods: A retrospective monocentric study of PC diagnosed in renal, hepatic or cardiac transplanted patients since 1989 was performed. All the patients were followed annually by digital rectal examination and prostate serum antigen (PSA) dosage.

Results: 57 PC were diagnosed in 1565 SOTR male patients (3.6%): 35 RTR, 15 HTR, and 7 CTR. Standard incidence ratio (SIR) was 41.9. Mean age at the time of diagnosis was 64.5 (60.5-69.2). Mean time between transplantation and PC diagnosis was 95.7 (39.0-139.5) months. Median PSA rate was 7.0 (6.2-13) ng/mL. Clinical stages were T1, T2, and T3, respectively, for 29, 22 and 6 patients. Diagnosis was done by screening in 52 patients, after prostatitis in 1 and bone pain in another. Three PC were discovered on prostate chips after transurethral resection. Two patients were treated by active surveillance. 39 (68%) patients (25 RTR, 11 HTR and 3 CTR) were treated by radical prostatectomy. Histological results were 30 pT2 and 9 pT3 tumors, with 7 positive surgical margins. Gleason score was 5, 6, 7, 8 and 9 in, respectively, in 2, 24, 11, 1 and 1 patients. One patient with positive pelvic nodes was treated with hormonal therapy (HT). One had a biochemical relapse at 10 months and underwent salvage radiotherapy. Median follow-up was 85.2 months (46.1-115.0). 23 (40.4%) patients died. Two (3.6%) RTR and 1 (1.8%) CTR died from their PC. Standard incidence ratio were, respectively, 42.4, 48.2 and 39 in RTR, HTR and CTR.

Conclusion: Systematic screening in male SOTR after 50 years old could not be recommended. In the last 3 decades, we diagnosed too many low-risk prostate cancers strongly increasing the SIR but failing to decrease prostate cancer related mortality. SOTR should undergo individual screening with prior MRI when PSA rates are high. Management should not be different from that of the general population.