A recent study published by Soria et al. in European Urology Focus described the development of a model that classifies the individual risk of recurrence and/or progression based on several prognostic factors. The investigators also validated the International Bladder Consultation Group (IBCG), model. They built a nomogram to predict PFS select patients who may benefit from adjuvant BCG instead of adjuvant chemotherapy using a multivariable Cox-regression model, a Cox-based nomogram, and decision curve analysis (DCA).
In this retrospective study, the investigators included 636 intermediate-risk NMIBC patients. The median follow-up period was 92.3 months (interquartile range IQR 56.3–117.5). During this time, the investigators found that 346 (54%) had disease recurrence, and 91 (14%) patients had disease progression. The median time to recurrence was 22 months (IQR 6–66) and 71 months to progression (IQR 36–108). The investigators identified time to recurrence < 1 year as the most important predictor of recurrence-free survival (PFS) (hazard ratio [HR] 86.22). Furthermore, they found that age (HR 1.04, p < 0.001), time to recurrence < 1 yr (HR 3.41, p < 0.001), tumor size > 3 cm (HR 1.51, p = 0.006), and tumor grade G2 (HR 1.73, p = 0.01) are independent predictors of PFS.
The authors demonstrated the improved accuracy of their model compared to the IBCG model, which does not consider some of these clinical variables. Using decision curve analysis, the authors show that their model is superior to the strategy of treating all the patients with BCG across threshold probabilities of progression to muscle-invasive disease between 5% and 40%. The authors note the study's limitations, including the lack of external validation in a different cohort.
This study is an important contribution towards personalized adjuvants strategies for NMIBC based on a refined nomogram. Prospective testing of these strategies is needed.
Written by: Bishoy M. Faltas, MD, Director of Bladder Cancer Research, Englander Institute for Precision Medicine, Weill Cornell Medicine, New York City, New York
Reference:
- Soria F, D'Andrea D, Abufaraj M, Moschini M, Giordano A, Gust KM, Karakiewicz PI, Babjuk M, Gontero P, Shariat SF. “Stratification of Intermediate-risk Non-muscle-invasive Bladder Cancer Patients: Implications for Adjuvant Therapies.” Eur Urol Focus. 2020 Jun 9:S2405-4569(20)30115-2. doi: 10.1016/j.euf.2020.05.004. Online ahead of print.