Clinical significance of NOTCH1 and FBXW7 alterations in adult T-cell leukemia/lymphoma.

Here, we investigated the clinical significance of NOTCH1 and FBXW7 alterations for adult T-cell leukemia/lymphoma (ATLL) treatment outcomes. NOTCH1 alterations were identified in 37 (14.4%) of 257 patients, of which 33 were single nucleotide variants/insertion-deletions in the PEST domain, and 7 were in the heterodimerization or LIN-12/Notch repeats domains. FBXW7 alterations were observed in nine ATLL patients (3.5%). For patients without allogeneic hematopoietic stem cell transplantation (HSCT), NOTCH1, but not FBXW7, alterations were significantly and independently associated with worse overall survival (median OS 0.5 years, 95% confidence interval [CI] 0.4-0.5 years for 27 patients with NOTCH1 alterations vs 1.8 years, 95% CI 1.3-2.2 years for 170 patients without). Also, for patients receiving mogamulizumab, but not allogeneic-HSCT, NOTCH1, but not FBXW7, alterations were significantly associated with worse survival (median survival from the first dose of mogamulizumab 0.4 years, 95% CI 0.3-0.5 years for 12 patients with NOTCH1 alterations vs 1.4 years, 95% CI 0.9-2.0 years for 87 without). In contrast, NOTCH1 alterations had no significant impact on survival of patients who did receive allogeneic-HSCT. Thus, mogamulizumab-containing treatment was unable to overcome treatment refractoriness of ATLL with NOTCH1 alterations. Therefore, patients with NOTCH1 alterations are recommended for allogeneic-HSCT.