Absolute Lymphocyte Count at the End of Induction as a Surrogate Marker for Minimal Residual Disease in T-cell Acute Lymphoblastic Leukemia

ABSTRACT

Objective: The relation of absolute lymphocyte count (ALC) with minimal residual disease(MRD) in T cell – acute lymphoblastic leukemia (T-ALL) is not known. The objective of thestudy was to correlate ALC with MRD, steroid-response and complete remission (CR).Methods: De-novo T- ALL patients (age 1-18 y) recruited prospectively; 52 enrolled, 9excluded, and 43 analyzed. 39 achieved CR and MRD was available for 28 patients; 23 wereMRD negative. Results: ALC did not correlate with steroid response and CR. Median (range)ALC at the end of induction was significantly higher in patients who were MRD negativecompared to MRD positive [1.24 (0.12, 6.69) vs 0.62 (0.15, 0.87); P=0.03], respectively.Patients having ALC ≥700 ×109 /L were significantly more likely to be MRD negative thanthose with lower values (P= 0.028) Conclusion: Our study suggests that ALC is a favorablefactor, and may act as surrogate marker for MRD