P208 A pilot study of low-dose capecitabine plus trastuzumab as first-line treatment for patients older than 75 years with HER2-positive advanced gastric cancer

Abstract

Background Elderly patients often present with concomitant co-morbidities and age-associated physiologic problems, such as impaired organ function and functional changes that make the selection of optimal treatment difficult. We report the treatment outcome in 13 elderly patients with HER2-positive advanced gastric cancer who were given low-dose capecitabine plus trastuzumab. Methods Patients older than 75 years with gastric cancer were eligible for inclusion if their tumours showed overexpression of HER2 protein by immunohistochemistry (IHC 3+), or gene amplification by FISH and IHC 2+. Capecitabine 1000 mg/m 2 was given orally twice a day for 14 days followed by a 1-week rest. Trastuzumab was given as an intravenous infusion of 8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks. Chemotherapy was given every 3 weeks for eight cycles. Findings Between December 2011 and July 2013, 13 consecutive patients (seven with IHC 3+ and six with IHC 2+ and FISH+) with a median age of 79 years (range 75–92) were enrolled. Eastern Cooperative Oncology Group (ECOG) performance status was 0 in one patient, 1 in seven patients, and 2 in five patients. A total of 54 cycles of capecitabine plus trastuzumab were administered (median of three cycles; range 2–8). Of the 12 patients with measurable lesions, the overall response rate was 41.6% (95% confidence interval [CI] 13.7–69.5). Disease control was achieved in 75.0% of patients. Median progression-free survival was 8.2 months (95% CI 2.5–13.7) and median overall survival was 10.9 months (95% CI 1.4–20.4). Grade 3–4 toxicities were stomatitis (7.6%) and anaemia (7.6%). No treatment-related deaths or symptomatic congestive heart failure were observed. Interpretation Our findings suggest that low-dose capecitabine plus trastuzumab is effective and well tolerated in elderly patients with advanced HER2-positive gastric cancer who are considered ineligible for combination chemotherapy. Prospective trials investigating this regimen in elderly patients with advanced gastric cancer are warranted.