Outcomes and Prognostic Factors (Figure 1, Table 2)
The median follow-up of the entire study cohort was 66months (range:6-114 months). The 5-year EFS and OS of the cohort were 80% (95%CI:71–89%) and 91% (95%CI: 85–97%), respectively (Figure 2&3). The 5-year EFS/OS in limited stage disease were 78% (95%CI: 65-91%)/89% (95%CI:79–99%) and in advanced stage 80% (95%CI: 68–92%) /91% (95%CI: 83–98%) respectively. Among the study cohort of 21 patients, there were three relapses and one toxic death. Three patients relapsed at a median of 37months (range:19-55 months) from diagnosis, of which two expired secondary to progression of the disease and one patient is alive in remission following salvage chemotherapy. None of the relapsed patients in the study cohort underwent hematopoietic stem cell transplant due to socio-economic constraints. Among the three relapsed patients only one had partial response (PR) post-induction.
Patients who presented late (≥3 months) from symptom onset had a significantly poorer 5-year event free survival of 44.4±22.2% compared to patients presenting early (<3months) 93.3±6.4% (p-0.030). Also, there was a trend towards poorer overall survival among pB-LBL patients presenting with osteolytic primaries compared to soft tissue lesions (5-year OS-75±21.7% vs 90.9±8.7%; p-0.080). None of the patients with MDD detected in the marrow baseline relapsed. Elevated serum lactate dehydrogenase (LDH) >1 ULN at diagnosis was associated with significantly poorer overall survival (p-0.032). Age, gender, stage, baseline bone marrow involvement, and Post-induction response had no bearing on survival outcomes.