Early treatment response including PPR and MRD positive at day 46 are strong independent negative predictors for CDKN2A-deleted ALL
When monitoring for early treatment responses,results showed thatn=78 (71.3%)patients were PGR and n=110 (99.1%)patients achieved first completeremission(CR).n=10 (41.6%) cases had PPR in T-ALL subgroup while nosignificant differences between two subgroups(P =0.148).There was no significant difference among the two subgroups for other early treatment response factors.(Table 2)
By the end of follow-up,n=14 relapse(n=5 death after relapse),n=1 induction failure,n=1 death due to severe pneumonia(SP) and one patient got second malignancy(Langerhans cell histiocytosis,LCH).Unfortunately, the patients got cutaneous peripheral T-cell lymphoma soon after HLA identical hematopoietic stem cell transplantation(HSCT) and finally died from gastrointestinal and pulmonary hemorrhage.The patient only had survived for 16 months after the first diagnosis.It should be noted that the patient had no other genetic abnormalities except CDKN2A deletion.
To test whether the co-variables described abovehad independent prognostic value in CDKN2A-deleted patients,we performed univariate analysis and multivariable analysis to assess their independent predictive power for EFS (Table 3).Univariate analysis revealed that EFS in CDKN2A-deleted ALL was associated with CNS2,cytogenetic risk groups,PPR,PER, and MRD≥0.01% at day 46(P <0.05) while no significant difference was observed in age,sex, and WBC counts.Seven variables(CNS2,WBC counts≥50×109/L,cytogenetic risk groups,PPR,PER, and MRD≥0.01% at day 19,46) were estimated by Cox regression models,results showed both PPR(HR=3.135,95%CI:1.138-8.638) and MRD positive at day 46(HR=3.812,95%CI: 1.388-10.464)wereindependent inferior prognostic factors for event-free survival(P <0.05),suggesting the adverse impact of these factors in CDKN2A-deleted ALL.(Table 4)