The following is a summary of “Advanced-Stage Hodgkin Lymphoma International Prognostic Index: Development and Validation of a Clinical Prediction Model From the HoLISTIC Consortium,” published in the April 2023 issue of Oncology by Rodday, et al.
Classic Hodgkin lymphoma (cHL) has been diagnosed for 25 years using the International Prognostic Score (IPS). Analysis, however, has revealed that patients receiving current treatment performed the IPS less than optimally. Therefore, for a study, researchers sought to develop and validate a modern clinical prediction model for advanced-stage cHL using multisource individual patient data.
The study utilized Hodgkin Lymphoma International Study for Individual Care Consortium data. Model development was performed on 4,022 patients with newly diagnosed advanced-stage adult cHL from eight international phases III clinical trials from 1996 to 2014. In addition, external validation was performed on 1,431 contemporaneously treated patients from four real-world cHL registries. Piecewise linear splines were evaluated to consider association over a full range of continuous variables. Cox proportional hazard models were used to estimate 5-year progression-free survival (PFS) and overall survival (OS).
In the development cohort, nodular sclerosis was the most prevalent histology, and the median age was 33 (18-65) years. The Kaplan-Meier estimates for the 5-year PFS and 5-year OS were 0.77 and 0.92, respectively. Age, sex, stage, mass, absolute lymphocyte count, hemoglobin, albumin, and a little difference for PFS versus OS were all significant predictive variables. Additionally, there are nonlinear correlations between age and absolute lymphocyte count and the results. In the development model, the 5-year PFS and OS c-statistics were 0.590 and 0.720 when optimism was considered. There was a reliable performance, good discrimination, and calibration regarding internal-external validation. There was improved calibration for PFS and OS compared to the IPS and superior OS discrimination.
The study developed and externally validated a clinical prediction model in >5,000 patients with advanced-stage cHL. Several novel nonlinear relationships were identified, and the prediction of patient outcomes was improved. An online calculator was created for individualized point-of-care use.