Focus on Prostate Cancer
Reporting combined outcomes with Trifecta and survival, continence, and potency (SCP) classification in 337 patients with prostate cancer treated with image-guided hypofractionated radiotherapy
- To report the image-guided hypofractionated radiotherapy (hypo-IGRT) outcome for patients with localised prostate cancer according to the new outcome models Trifecta (cancer control, urinary continence, and sexual potency) and SCP (failure-free survival, continence and potency).
Patients and Methods
- Between August 2006 and January 2011, 337 patients with cT1–T2N0M0 prostate cancer (median age 73 years) were eligible for a prospective longitudinal study on hypo-IGRT (70.2 Gy/26 fractions) in our Department.
- Patients completed four questionnaires before treatment, and during follow-up: the International Index of Erectile Function-5 (IIEF-5), the International Prostate Symptom Score (IPSS), and the European Organization for Research and Treatment of Cancer prostate-cancer-specific Quality of Life Questionnaires (QLQ) QLQ-PR25 and QLQ-C30.
- Baseline and follow-up patient data were analysed according to the Trifecta and SCP outcome models. Cancer control, continence and potency were defined respectively as no evidence of disease, score 1 or 2 for item 36 of the QLQ-PR25 questionnaire, and total score of >16 on the IIEF-5 questionnaire.
- Patients receiving androgen-deprivation therapy (ADT) at any time were excluded.
- Trifecta criteria at baseline were met in 72 patients (42% of all ADT-free patients with completed questionnaires).
- Both at 12 and 24 months after hypo-IGRT, 57% of the Trifecta patients at baseline were still meeting the Trifecta criteria (both oncological and functional success according to the SCP model).
- The main reason for failing the Trifecta criteria during follow-up was erectile dysfunction: in 18 patients after 6 months follow-up, in 12 patients after 12 months follow-up, and in eight patients after 24 months.
- Actuarial 2-year Trifecta failure-free survival rate was 44% (95% confidence interval 27–60%).
- In multivariate analysis no predictors of Trifecta failure were identified. Missing questionnaires was the main limitation of the study.
- The Trifecta and SCP classifications can be used as tools to report RT outcome.