Most patients with chronic lymphocytic leukaemia (CLL) are diagnosed with early stage disease and managed with active surveillance. The individual course of subjects with early stage CLL is heterogeneous and their probability of needing treatment is hardly anticipated at diagnosis. The strategy medical guidelines recommend for patients with early-stage CLL who don’t have disease symptoms, is based on a ‘watch and wait’ approach. A new prognostic tool predicts how long someone diagnosed with CLL will be able to wait before starting cancer treatment.
The aim of the study was to develop an international prognostic score (IPS-E) to predict time to first treatment (TTFT) in CLL patients with early, asymptomatic disease. Individual patient data from 11 international cohorts of patients with early stage CLL (n=4933) were analyzed to build and validate the prognostic score.
Three covariates were consistently and independently correlated with TTFT: unmutated IGHV genes, absolute lymphocyte count >15 x109/l, and presence of palpable lymph nodes. The IPS-E was the sum of the covariates (one point each). Furthermore, a distinction was made between low-risk (score 0), intermediate-risk (score 1) and high-risk patients (score 2-3) showing a distinct TTFT.
The-index was 0.74 in the training series and 0.70 in the aggregate of validation series. By meta-analysis of the training and validation cohorts, the 5-year cumulative risk of treatment start was 8.4%, 28.4%, and 61.2% among low-risk, intermediate-risk, and high-risk patients, respectively.
In conclusion, the IPS-E is a simple and robust prognostic tool that can predict the treatment needs of CLL patients at an early stage. The tool can be useful in clinical management and in setting up early stage clinical trials.