Molecular IPSS Adds No Prognostic Power for HMA-Treated MDS

The Molecular International Prognostic Scoring System (IPSS-M) did not provide additional prognostic power compared with the IPSS-revised (IPSS-R) among patients with myelodysplastic syndrome (MDS) undergoing hypomethylating agent (HMA) therapy, according to an abstract from the 65th ASH Annual Meeting and Exposition.

Kelly S. Chien, MD, of the University of Texas MD Anderson Cancer Center in Houston, and colleagues conducted a retrospective study of patients with MDS treated with HMA therapy at a single tertiary cancer center. They sought to assess the efficacy of the IPSS-M. The study included 455 patients treated with HMA. About one-third (35%) had therapy-related MDS, one-third (37%) had complex cytogenetics, and one-third (37%) had TP53 mutations.

According to the IPSS-R, 58% of patients had high- or very high-risk disease; however, according to the IPSS-M, 75% had higher-risk disease, defined as moderately high, high, or very high.

Overall survival per the IPSS-R was 60.0 months in very low-risk disease; 87.4 months in low-risk disease; 36.2 months in intermediate-risk disease; 23.7 months in high-risk disease; and 12.8 months in very high-risk disease.

When the patients were reclassified by the IPSS-M, results were similar, with overall survival of not reached, 60.0 months, 40.8 months, 44.2 months, 33.4 months, and 16.6 months for very low-, low-, moderate low-intermediate-, high-, and very high-risk disease, respectively. The concordance index for the IPSS-M in this group of patients with MDS treated with HMA was 0.648.

“When analyzing patients with MDS who were more likely to undergo HMA as per standard-of-care treatment (those with IPSS-M moderate low-, moderate high-, high-, and very high-risk disease), the IPSS-M remained statistically significant (P<.0001) though less discerning in the patients with moderate-risk MDS, as seen by the concordance index of 0.620,” the researchers wrote in the abstract.

Based on these results, the researchers concluded that although overall survival was still inversely proportional to the IPSS-M, the molecular risk stratification provided no additional prognostic power. They said that further validation of prognostic scoring systems in patients treated with HMA is needed.

Reference

Chien K, Urrutia S, Li Z, et al. Performance of the Molecular International Prognostic Scoring System (IPSS-M) in hypomethylating agent–treated patients with myelodysplastic syndromes. Abstract #1857. Presented at the 65th ASH Annual Meeting and Exposition; December 9-12, 2023; San Diego, California.