Brief ArticleTime-to-Event Ratio to Predict Outcome in Patients with Acute Myeloid Leukemia Undergoing Allogeneic Hematopoietic Cell Transplantation?

- Time to transplantation, although is commonly used as a surrogate marker for patients with AML in CR1, it is composed of 2 components (diagnosis to CR and CR to transplantation) offsets each other. A new time to-event ratio (DCTR = diagnosis to CR/CR to transplantation) predicts leukemia-free survival DCTR seems a better surrogate marker than any other time-to-event variable, but this should be tested and confirmed by other groups.
- Patients with higher DCTR (>1.0) had significantly worse leukemia-free survival by 5 years than those with lower DCTR (≤1.0; P = .01). DCTR also showed a statistically significant association in the multiple regression analysis (HR, 1.8; 95% CI, 1.1 to 3.2; P = .03). These patients also had a marginally worse 5-year overall survival than those with lower DCTR (≤1.0; 31% [14% to 49%] versus 54% [43% to 64%]; P = .06).
- DCTR predicted survival better than the other measures of TTT, CR → HCT, and diagnosis → CR and therefore should be preferred in allogeneic HCT studies after further validation in larger and independent cohorts.

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