The impact of anticancer therapy on quality of life has been receiving increasing attention, particularly with diseases such as low-grade non-Hodgkin’s lymphoma (NHL), where palliation rather than cure is the primary objective of therapy. The Functional Assessment of Cancer Therapy-General (FACT-G) is a validated questionnaire that captures the major areas of patients’ subjective evaluation of the impact of their cancer on the following domains: physical, social, emotional, functional, and relationship with doctor (J Clin Oncol 11:570-579, 1993). There are two to seven questions per domain, yielding a total score from 0 to 112.
We used the FACT-G survey to assess quality of life in a phase III randomized trial of ibritumomab tiuxetan (Zevalin) radioimmunotherapy vs rituximab(Drug information on rituximab) (Rituxan) immunotherapy in patients with relapsed or refractory low-grade, follicular, or transformed NHL. The phase III trial enrolled 73 patients on the ibritumomab tiuxetan arm and 70 patients on the rituximab arm, with the following baseline characteristics: median age, 59 years (range: 29 to 80 years); 51% female; largest tumor > 5 cm, 45%; bone marrow involvement, 39%; and International Prognostic Index intermediate/high or high-risk group, 12%.
FACT-G total scores and subscale scores were compared between baseline and 3 months posttherapy within each of the treatment arms. Three months was chosen because patients were most likely to be in a maximal response from either therapy at this point. Not all patients completed the questionnaires; 62% and 51% of patients on the ibritumomab tiuxetan and rituximab arms, respectively, completed both a baseline and a 3-month FACT-G survey.
Of note, the mean baseline FACT-G score, prior to treatment, was high in both treatment arms: 86.9 for ibritumomab tiuxetan and 90.7 for rituximab. At 3 months posttherapy, the ibritumomab tiuxetan group experienced a statistically significant increase in the FACT-G total score (86.9 to 93.3; P = .001); the increase for the rituximab arm was not statistically significant (90.7 to 93.4; P = .185). Patients on the ibritumomab tiuxetan arm also experienced statistically significant improvement in the following FACT-G subscales: emotional, physical, and functional well-being; the rituximab group experienced a statistically significant improvement in the emotional subscale.
CONCLUSION: Ibritumomab tiuxetan therapy results in a statistically significant improvement in patient self-assessed quality of life. Such information may help patients and physicians with their treatment decisions.