A randomized controlled trial found that nomograms based on multiple Cox regression models could effectively predict the risk factors associated with overall survival and cancer-specific survival in patients with localized prostate cancer as well as assess survival differences between surgery and radiotherapy.
Prostate cancer affects a substantial proportion of men across the globe, with more than 80% of the patients being diagnosed with localized prostate cancer, which corresponds to tumor (T) stage of T2c or below. There is a lack of definite guidelines for treatment modalities in localized prostate cancer.
A randomized controlled trial aimed to formulate a nomogram for predicting the risk factors of overall survival (OS) and cancer-specific survival (CSS) in elderly individuals with localized prostate cancer based on surgery- and radiotherapy-based survival differences. The findings are published in the journal BioMed Central Urology.
Baseline Characteristics
The study enrolled 90,434 patients, with 63,328 and 27,106 patients in the training and validation cohorts, respectively. The mean age of the patients was 71.4 ± 5.29 years, and the majority of patients were White (78.3%). Of the total patients, 18.97% had grade I, 44.73% had grade II, 36.27% had grade III, and 0.03% had grade IV tumors. There were no statistically significant differences in the baseline features of the two groups.
Prognostic Factors in Localized Prostate Cancer
Based on the COX regression analysis, the factors related to patient outcomes were age, T stage, surgery, chemotherapy, radiotherapy, biopsy Gleason Score, prostate-specific antigen (PSA), age, race, tumor grade, and marriage. Independent risk factors affecting CSS were Gleason score, age, race, marriage, surgery, PSA, T stage, and radiotherapy, whereas those associated with OS outcomes were age, race, Gleason score, PSA, marriage, surgery, and radiotherapy.
Nomogram Construction and Survival Prediction
Internal cross-validation, calibration curve, area under curve, and external temporal validation values indicated that the discriminability strength of the nomogram was high, based on predicting the CSS and OS patient outcomes.
Clinical Application of Prediction Model
The OS and CSS nomograms demonstrated the best clinical potential for predicting localized prostate cancer. The OS and CSS rates were found to be relatively higher in patients in the low-risk group compared to high-risk group patients in training and validation cohorts. The lowest OS and CSS rates were observed in high-risk patients who did not undergo radiotherapy but received local irradiation.
Source:
Zhanghuang, C., Zhu, J., Li, Y., Wang, J., Ma, J., Li, L., Yao, Z., Ji, F., Wu, C., Tang, H., Xie, Y., Yan, B., & Yang, Z. (2024). Prognostic significance of surgery and radiotherapy in elderly patients with localized prostate cancer: establishing and time-based external validation a nomogram from SEER-based study. BMC Urology, 24(1). https://doi.org/10.1186/s12894-023-01384-6
