Lapatinib monotherapy in HER2+ relapsed or refractory inflammatory breast cancer (IBC): quality of life (QOL) assessment.

Abstract

Abstract Abstract #4097 Background: IBC is a rare, clinically distinct and aggressive form of breast cancer characterized by severe pain and a poor prognosis. EGF103009 was a phase II, open-label, multicenter study that showed lapatinib monotherapy is clinically active in women with relapsed/refractory HER2+ IBC that progressed on prior therapy with anthracylines, taxanes, and trastuzumab. This analysis focuses on the impact of lapatinib on QOL and pain symptoms (endpoints added during a study amendment) in these patients.
 Methods: QOL was assessed using the EORTC QLQ C-30, a 30-item instrument that assesses 15 domains consisting of 5 functional scales (physical, role, emotional, cognitive, social) and 9 symptom scales (fatigue, nausea and vomiting, pain, dyspnea, insomnia, appetite loss, constipation, diarrhea, financial difficulties) and a global QOL item. A high score for a functional scale/global QOL indicates a high and healthy level of functioning/QOL whereas a high score for a symptom scale indicates a high level of symptoms/problems. Pain was specifically assessed using the Brief Pain Inventory-Short Form (BPI-SF), which includes 4 severity items and 7 items assessing pain interference with general activity, mood, work, walking ability, relations, sleep, and enjoyment of life. Scoring produces 4 scores: pain severity, overall pain interference, activity-related pain interference and mood-related pain interference. Higher scores indicate greater pain severity or pain interference. Both questionnaires were completed at baseline and every 4 weeks thereafter. Mean change in scores from baseline (with 95% CI) were provided by visit.
 Results: Because QOL/pain scales were added late in the study, only 33 of 126 patients in the HER2+ cohort completed at least one question in the health outcome questionnaires at baseline. At week 8, 64% (n=21) of patients completed assessments, and the results showed moderate improvement (10-20 points) in average EORTC QLC scores for global QOL, role functioning and social subscales. The physical function subscale also showed improvement (9 points). All symptom scales (except diarrhea) were lower than baseline at most scheduled visits indicating improvement in symptoms. Scores for all 4 summary pain scores of the BPI-SF at week 8 were also lower than baseline values suggesting improvement in pain severity and pain interference (decrease ranged from 1.3 to 2.7 points). Sixteen of the 33 patients (48%) had partial response to treatment and 9 had stable disease.
 Conclusions: Results suggest that lapatinib monotherapy may improve level of functioning/QOL and provide relief from most symptoms, including pain, in the short term. These QOL benefits add to the clinical improvement associated with lapatinib therapy in these heavily pre-treated patients with an aggressive form of breast cancer. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4097.