Improvements in Health-Related Quality of Life of Patients with DLBCL after Treatment with Yttrium-90 Ibritumomab Tiuxetan (⁹⁰y-Zevalin).

PURPOSE: This health-related quality of life (HRQL) study aimed to evaluate the impact of ⁹⁰y-Zevalin therapy on the HRQL of older patients with relapsed diffuse large B-cell lymphoma (DLBCL) not eligible for stem cell transplantation. Ppsychometric performance of the FACT-G and EQ-5D in the same patient sample was also evaluated. The study was conducted alongside a single arm, phase II clinical trial of ⁹⁰Y-Zevalin radioimmunotherapy.

METHODS: The FACT-G scale contains 27 questions, grouped according to 4 “dimensions” of HRQL relevant to patients with cancer: Physical, Functional, Social and Emotional well-being. The scale provides a total score for overall HRQL and subscale scores for each dimension. The EQ-5D is a generic measure of HRQL used in a range of diseases and comprises a descriptive classification based on 5 broad dimensions and a visual analogue scale. Data from the 2 measures were analyzed with descriptive statistics. Validity was assessed in terms of correlations between individual dimensions. Changes in the dimensions and total scores of the FACT-G and EQ-5D from baseline to wk 12 post-⁹⁰Y-Zevalin therapy were assessed using paired t-tests. Wk 12 corresponded to the time of expected maximal response to ⁹⁰Y-Zevalin therapy.

RESULTS: Sixty-six of 104 patients enrolled in the clinical study completed the FACT-G and EQ-5D questionnaires at baseline and 35 completed the questionnaires at wk 12. Those who completed the questionnaires at both baseline and wk 12 were more likely to have responded to ⁹⁰Y-Zevalin (80% were responders) although they were comparable in terms of age (median = 72 yrs) and gender (54% male) to those who only completed the questionnaires at baseline. At baseline, the dimensions of HRQL with the worst scores and therefore most affected by DLBCL, included areas related to energy, pain, anxiety and depression, which would be expected given the symptoms commonly associated with DLBCL such as fatigue. The percentage of patients reporting “some or extreme problems” on each of the EQ-5D dimensions at baseline are summarized in the table. Moderate correlations were observed between the Physical Well-being of the FACT-G and the Usual Activities (=0.60) and Pain/Discomfort (=0.70) dimensions of the EQ-5D. The Emotional Well-being dimension of the FACT-G was moderately correlated with the Anxiety/Depression on the EQ-5D (=0.66). These data suggest the FACT-G and the EQ-5D were measuring some common concepts to patients. All summary dimensions of the FACT-G and EQ-5D showed either a positive trend or little change after treatment with ⁹⁰Y-Zevalin, with the Physical Well-being dimension of the FACT-G reaching statistical significance (P=0.03) and measuring a 10% improvement over baseline. The change in total score of the FACT-G almost reached significance (P=0.06), as did the emotional dimension of the FACT-G (P=0.10) and the mobility dimension of the EQ-5D (P=0.08).

CONCLUSION: Although number of participating patients was small, the EQ-5D and the FACT-G have demonstrated validity for patients with DLBCL following treatment with ⁹⁰Y-Zevalin. The greatest impact of ⁹⁰Y-Zevalin therapy is an improvement in physical well-being, with an increased level of energy, reduced amount of pain and reduced level of “feeling ill”.