An international prognostic index for patients with chronic lymphocytic leukemia (CLL), known as CLL-IPI, was predictive of time from diagnosis to first treatment (TTFT) and 5-year median overall survival in patients across different risk categories treated with chemoimmunotherapy, according to a systematic review and meta-analysis published in Blood (2018 Jan 18;131[3]:365-8).
But limited data were available for patients treated with targeted therapies that are likely to have a profound effect on overall survival; thereby restricting the use of CLL-IPI in current clinical practice.
Novel therapies such as ibrutinib, idelalisib, and venetoclax have changed the treatment landscape for CLL, Stefano Molica, MD, of Azienda Ospedaliera Pugliese-Ciaccio, Catanzaro, Italy, and his colleagues wrote. “Because observation remains the standard of care for asymptomatic early-stage patients, the introduction of these agents does not impact the utility of the CLL-IPI for predicting time from diagnosis to first treatment, but it likely has a profound impact on the survival of patients of all risk categories once treatment is indicated.”
The CLL-IPI tool, first published in 2016 to predict clinical outcomes in CLL patients, combines five parameters: age, clinical stage, TP53 status [normal vs. del(17p) and/or TP53 mutation], immunoglobulin heavy chain–variable mutational status, and serum b2-microglobulin. The prognostic tool was validated across several studies conducted in different countries with diverse practice settings, including academic hospitals, national population-based cohorts, and clinical trials.
The researchers conducted a systematic review and meta-analysis to understand the utility of CLL-IPI tool in predicting OS and TTFT across each risk category of CLL patients.
They included nine studies with 7,843 patients to assess the impact of the CLL-IPI on overall survival. The patient distribution into the CLL-IPI risk categories was low risk (median 45.9%), intermediate risk (median 30%), high risk (median 16.5%), and very high risk (median 3.6%).
The researchers relied on 11 series comprising 7,383 patients to assess 5-year survival probability, which was 92% for low risk, 81% for intermediate risk, 60% for high risk, and 34% for very high risk. They used seven studies comprising 5,206 patients to assess TTFT and found that the probability of remaining treatment free at 5 years was 82% in the low-risk group, 45% in the intermediate-risk group, 30% in the high-risk group, and 16% in the very-high-risk group.
Although a significant step toward harmonizing international prognostication for CLL, additional studies validating the utility of the CLL-IPI for predicting OS in patients treated with targeted therapy are needed, they wrote.
The researchers reported having no financial disclosures.