Baseline clinical characteristics
Charts of 120 patients were identified (CHOP=108, EPOCH=12). Overall, there were 64(53%) men and 56(47%) women. 11(92%) men received EPOCH while 53(49%) men received CHOP (p=0.01). There were no statistical differences in BMI, age at diagnosis, types of lymphoma, ECOG performance score, presence of B-symptoms, comorbidities and stage of NHL between the two treatment groups (Table 1). Majority of patients,105(97.2%) in the CHOP group were already on ART prior to starting chemotherapy, and only 3 patients (2.8%) in the CHOP group started ART after completion of chemotherapy cycles. All patients in the EPOCH group were on ART prior to starting chemotherapy. Most patients were on first line ART (CHOP=101, 94%; EPOCH=12, 100%) with more proportion of the EPOCH group (n=10, 83%) taking Tenofovir/Lamivudine/Efavirenz than the CHOP group (n=24, 22%); (p<0.001), but there were no differences in the other ART regimens and PCP prophylaxis (Table 2). No patient had ART interrupted while receiving chemotherapy.
Fifty-nine (49%) patients completed 6 and more cycles of chemotherapy, including 51(47%) in the CHOP group and 8(67%) in the EPOCH group, p=0.2. Reasons for non-completion of chemotherapy cycles were serious adverse events (n=12, 10%), other reasons (n=4, 3%), and were not described in 104(87%) patients. Nineteen patients (18%) in the CHOP group and 3(25%) in the EPOCH group had serious adverse event, p=0.53. Most were laboratory adverse events like neutropenia (CHOP=13, 12%; EPOCH=2, 17%); p=0.65), anaemia (CHOP=12, 12%; EPOCH=1, 8%; P=0.71), and thrombocytopenia (CHOP=7, 6%; EPOCH=0; p=0.36). Others were sepsis (CHOP=1), treatment related death (EPOCH=1) and hepatic encephalopathy (CHOP=1), (Table 3). The lowest neutrophil count recorded was 0.12 x10^3/uL after the first cycle of chemotherapy in a patient treated with EPOCH in figure 1.
Treatment response and survival
Only patients who completed at least 6 cycles of chemotherapy were evaluated for response. Overall treatment response rate was 40% in the CHOP group and 59% in the EPOCH group (P=0.66). Complete response (CR) was achieved in 29(27%) patients in the CHOP group and 5(42%) patients in the EPOCH group. Partial response was observed in 16(13%) patients in the CHOP group and 2(17%) patients in the EPOCH group. There was no statistical difference between all the response categories (Table 4).
The entire study population had a one year (12 months) overall survival (OS) rate of 56.7% (95% CI, 45.4–66.5), (Figure 2). Patients treated with CHOP had a shorter one year OS of 54.5% (42.8–64.8) than those treated with EPOCH, 80.2% (95% CI, 40.3–94.8), but the difference was not statistically significant (Hazard ratio, 0.43 (95% CI, 0.10-1.78; p=0.24), (Figure 3). Subset analysis for patients with DLBCL showed a one year OS rate of 56.1% (95% CI, 33.0–74.0) in the CHOP group and 100% in the EPOCH group (HR, <0.001, p=1). Predictors of survival were analysed using patients’ age, sex, type of chemotherapy received, completion of 6 or more cycles of chemotherapy, type of lymphoma, stage of lymphoma, presence of B-symptoms and comorbidities. At univariable analysis, factors that were associated with favourable survival were ECOG performance score of 3-4, BMI 18.5-24.9 kg/m2 and completion of 6 or more cycles of chemotherapy. However, at multivariable analysis, only BMI 18.5-24.9 kg/m2 (normal BMI), (p=0.03) and completion of 6 or more cycles of chemotherapy, (p<0.001) were favourably associated with survival, Table 5.