Patients with metastatic castrate-sensitive prostate cancer (mCSPC) must deal with pain as a significant aspect of their quality of life. It was unknown, nevertheless, whether a dynamic change in pain over time in these patients can predict overall survival (OS) or time to radiographic progression (TTRP).
The study of LATITUDE, which randomized men with de novo mCSPC to receive ADT with abiraterone versus ADT alone, was exploratory. The Brief Pain Inventory-Short Form gathered data on the patient-reported worst pain score (WPS). Researchers used independent univariate joint models to ascertain the relationship between dynamic changes in WPS and OS, and TTRP used independent univariate joint models. A Cox proportional hazard regression model was built for the time-to-event submodel. A linear mixed effect model was constructed for the longitudinal submodel. The random effect connected the two submodels. Markov chain Monte Carlo techniques were used to fit the joint models.
Over 1,125 patients in total who had at least 3 measures of their pain scores were included. Initially, patients were divided into two groups depending on the occurrence of early discomfort. Patients’ median OS and median TTRP at baseline for those with and without pain were 35.7 and 41.1 months and 31.8 and 23.1 months, respectively. According to Cox multivariable regression, a baseline WPS that was 1 unit higher was linked to worse OS and TTRP (hazard ratio [HR]: 1.05; 95% CI: 1.02-1.09); and time-dependent area under curve [tAUC]: 0.64) and inferior TTRP (HR: 1.05 [1.01-1.08]; tAUC 0.64). According to independent joint modeling, a dynamic rise of one unit in the present value of WPS was linked to worse OS and TTRP (HR: 1.32 [1.26-1.38]; tAUC: 0.74) and TTRP (HR: 1.32 [1.26-1.38]; tAUC 0.70).
The data mentioned above drew attention to a potential dynamic interaction between patient-reported pain with OS and TTRP in mCSPC. Such dynamic pain evaluation was found to have better predictive capacity than baseline pain, as indicated by greater tAUC. Beyond its position as a crucial aspect of quality of life, dynamic evaluation of pain score offered the ability to adjust subsequent treatment based on response to the first therapy.