Table 3.

Multivariable hazard of relapse in AYA by time of relapse

Relapse during therapya (all AYA: n = 93)Relapse after completion of therapya (AYA who completed therapy: n = 42)
HR (95% CI)PHR (95% CI)P
Duration of therapy
Duration of maintenanceb0.9 (0.7–1.2)0.60.7 (0.6–0.8)<0.001
Duration of consolidationb0.9 (0.7–1.2)0.60.8 (0.6–1.0)0.03
Oncology service and therapy types
Pediatric oncology + pediatric therapy1.0 (—)1.0 (—)
 Adult oncology + adult therapy1.9 (0.7–5.2)0.20.8 (0.1–4.7)0.8
 Mixed oncology + mixed therapy0.3 (0.1–1.5)0.20.3 (0.04–1.9)0.2
Insurance and SES
Private insurance + high SES1.0 (—)1.0 (—)
 Public insurance + low SES0.5 (0.2–1.4)0.26.8 (0.8–60.8)0.09
 Mixed profile0.6 (0.2–1.7)0.41.2 (0.1–12.5)0.9
Race and ethnicity
Non-Hispanic white1.0 (—)1.0 (—)
 Nonwhite race/ethnicity2.2 (1.0–4.8)0.050.2 (0.03–1.9)0.2
Clinical trial enrollment
Enrolled on clinical trial1.0 (—)1.0 (—)
 Not enrolled on clinical trial2.6 (1.0–6.3)0.041.1 (0.2–6.0)0.9
Female1.0 (—)1.0 (—)
 Male0.8 (0.4–1.7)0.61.3 (0.3–5.1)0.7
 Age, y1.00 (1.0–1.1)0.51.0 (0.9–1.1)1.0
Time in monthsb1.1 (0.8–1.4)0.70.98 (0.96–1.0)0.03
Clinical prognosticators
WBC <50K1.0 (—)1.0 (—)
 WBC >50K1.6 (0.8–3.1)0.27.9 (1.6–38.8)0.01
Precursor B cell1.0 (—)1.0 (—)
 T cell1.3 (0.6–2.6)0.50.3 (0.04–1.6)0.2
 No high-risk cytogenetics identified1.0 (—)1.0 (—)
 High-risk cytogenetic profile1.2 (0.6–2.6)0.7
 M1 marrow at end of inductionc1.0 (—)1.0 (—)
 M2-M3 marrow at end of inductionc2.0 (0.9–4.9)0.11.2 (0.2–6.6)0.9
 CNS negative1.0 (—)
 CNS positive8.6 (2.1–35.0)0.003
  • aAdjusted discrete time survival analysis, modeling hazard of relapse with death due to nonrelapse causes and date of last contact as censoring events. Bolded values represent statistically significant findings. On-therapy model adjusted for AYA*time interaction.

  • bThese variables were modeled as time-varying covariates. Time at risk represents: (i) months from CR1 in the model calculating hazard of relapse on therapy; (ii) months from completion of therapy in the model calculating hazard of relapse after completing therapy. HRs represent each additional month of time from remission/completion of therapy, or each additional month of therapy.

  • cPatients with M2-M3 marrows at the end of induction were compared with patients who either (i) had M1 marrows at the end of induction or (ii) did not have a documented end of induction marrow, but the first marrow documented after initiation of treatment (>36 days) was M1.