1. ¹School of Surgery and Pathology, University of Western Australia, Nedlands 6009, Australia
2. ²The St John of God CRC Unit, Perth, Western Australia, Nedlands 6009, Australia
3. ³Western Australian Institute for Medical Research, University of Western Australia, Nedlands 6009, Australia

Correspondence: Dr B Iacopetta, School of Surgery and Pathology M507, University of Western Australia, Nedlands 6009, Australia. E-mail: barry.iacopetta@uwa.edu.au

Received 6 November 2006; Revised 15 January 2007; Accepted 15 January 2007; Published online 13 February 2007.

Abstract

Two recent North American studies have shown that completion of 5-fluorouracil (5FU)-based adjuvant chemotherapy is a major prognostic factor for the survival of elderly stage III colon cancer patients. The aim of the present study was to confirm this finding in a population-based series from Australia. The study cohort comprised 851 stage III colon cancer patients treated by surgery alone and 461 who initiated the Mayo chemotherapy regime. One-third of patients who initiated chemotherapy failed to complete more than three cycles of treatment. Independent predictors for failure to complete were treatment in district or rural hospitals, low socioeconomic index and treatment by a low-volume surgeon. Patients who failed to complete chemotherapy showed worse cancer-specific survival compared not only to those who completed treatment (HR=2.24; 95% confidence interval (CI) (1.66–3.03), P<0.001) but also to those treated by surgery alone (HR=1.37; 95% CI (1.09–1.72), P=0.008). The current and previous studies demonstrate the importance of completing adjuvant 5-FU-based chemotherapy for colon cancer. Further prospective studies are required to identify better the physiological and socioeconomic factors responsible for failure to complete chemotherapy so that appropriate improvements in health service delivery can be made.