Factors associated with early termination of CHOP therapy and the impact on survival among patients with chemosensitive intermediate-grade non-Hodgkin's lymphoma

Six to eight cycles of CHOP therapy (cyclophosphamide, doxorubicin, vincristine, and prednisone) is standard for intermediate-grade non-Hodgkin's lymphoma (NHL) but is associated with toxicity that may cause premature termination of therapy. We studied factors associated with premature termination of CHOP therapy (receiving fewer than 6 cycles) and the relationship of premature termination with survival. Subjects consisted of a population-based sample of Iowa residents with intermediate-grade NHL who were planned to receive > or = 6 or more cycles of CHOP and who were chemosensitive (ie, achieved a documented partial or complete response to CHOP). In a comparison with patients 18-59 years of age, the odds of premature termination of CHOP therapy was 2.6 (95% CI, 0.7-9.2) for those aged 60-74 and 6.2 (95% CI, 1.7-23.3) for those aged > or = 75. Patients with cycle 1 febrile neutropenia hospitalization (FNH) were 4.4 times (95% CI, 1.4-13.8) more likely to terminate CHOP prematurely than those without cycle 1 FNH. Among patients aged 60-74, but not those aged > or = 75, premature termination appeared to be associated with decreased 5-year survival (hazard ratio [HR] = 6.0; 95% CI, 2.4-15.2) compared with those completing CHOP therapy (HR = 2.1; 95% CI, 1.0-4.2). Findings for overall survival were similar. First-cycle FNH and age > or = 60 years were associated with premature termination of CHOP therapy. The association of premature termination with survival among chemosensitive patients differed by age.