A predictive model for life-threatening neutropenia and febrile neutropenia after the first course of CHOP chemotherapy in patients with aggressive non-Hodgkin's lymphoma.

The purpose of this study was to develop a model for predicting the occurrence of life-threatening neutropenia (LN, ANC < or = 0.5 x 10(9)/l) and febrile neutropenia (FN, an ANC < 0.5x10(9)/l in association with a body temperature of > or = 38.3 degrees C) after the first cycle of CHOP therapy in patients newly diagnosed with aggressive NHL. One hundred and forty-five patients, aged > or = 15 years, with newly diagnosed diffuse mixed, diffuse large-cell or large-cell immunoblastic lymphoma (IWF categories, F, G, H), who had been treated with CHOP at King Chulalongkorn Memorial Hospital between June 1994 and December 1998, were entered into the study. The criteria for eligibility included complete work-up for baseline evaluation, treatment with standard CHOP chemotherapy, at least one complete blood count performed during days 8-14 post-treatment or if at any time the patients experienced a BT of > or = 38.3 degrees C and were not treated with any colony-stimulating factors (CSFs). The median age of the patients was 47 years (range, 17-78). Forty-eight percent of the patients were in stage III/IV, 36% had ECOG performance status (PS) II-IV, 30% had > or = 2 extranodal diseases, 59% had serum LDH > 1 x normal and 23% had bone marrow involvement. The frequencies of patients in the low-, low-intermediate, high-intermediate and high risk groups according to the international index were 29%, 28%, 17% and 26%, respectively. Thirty-nine percent of the patients had LN at nadir and 33% developed FN after the first course of CHOP. By using stepwise logistic regression analysis, the pretreatment variables independently predictive of the LN at nadir and the FN were serum albumin concentration of < or = 3.5 g/dl, serum LDH > 1 x normal and whether there was bone marrow involvement of lymphoma at presentation. The model, based on the incorporation of these three factors, identified three risk groups of patients with a predicted probability of developing LN at nadir of 81.5% (95% CI, 68.5-90.7) (high risk), 23.9% (95% CI, 12.6-38.8) (intermediate risk) and 4.4% (95% CI, 0.5-15.1) (low risk). The predicted rate of FN in the three groups were 72.2% (95% CI, 58.4-83.5), 17.4% (95% CI, 7.8-31.4) and 2.2% (95% CI, 0.05-11.8), respectively. In conclusion, our model could be used as a means to identify patients with newly diagnosed aggressive NHL, treated with CHOP, who are at high risk (> or = 50% probability) of developing post-first course LN and FN, in whom CSF and/or antibiotic prophylaxis might be indicated.