1. ¹Division of Clinical Oncology, Department of Internal Medicine I, University Hospital, Waehringer Guertel 18-20, Vienna A-1090, Austria
2. ²Department of Surgery, University Hospital, Waehringer Guertel 18-20, Vienna A-1090, Austria
3. ³Department of Surgery, Wr. Neustadt General Hospital, Corvinusring 3-5, Wr.Neustadt A-2700, Austria
4. ⁴Department of Surgery, Neunkirchen General Hospital, Peischinger Strasse 19, Neunkirchen A-2620, Austria
5. ⁵Department of Internal Medicine, Kirchdorf General Hospital, Kirchdorf an der Krems A-4560, Austria

Correspondence: Dr B Schuell, E-mail: birgit.schuell@meduniwien.ac.at

Revised 1 August 2005; Accepted 12 August 2005; Published online 13 September 2005.

Abstract

To investigate whether a relationship between chemotherapy-associated adverse events and treatment efficacy exists, we have analysed the toxicity, objective response and survival data of 303 patients with advanced colorectal cancer. Patients were divided into two groups: the first with beneficial effect (I, n=245), and the second with progressive disease (II, n=58). Differences in terms of incidence rates, type and severity of adverse events were analysed with univariate and multivariate models. The median number of side effects in group I was 6 vs 4 in group II (OR=1.342; P=0.0001). An inverse correlation between disease control and treatment tolerance was confirmed when side effects were analysed according to severity and type of treatment-associated toxicities (haematological: P=0.0005 vs nonhaematological P=0.0001). When median survival was analysed according to the number of adverse events, it was 10 (95% CI, 3–7), 16 (14–18), and 18 (16–20) months in case of 0–1, 2–5, and 6 adverse events, respectively (P=0.01). In conclusion, the results of this analysis suggest that occurrence of side effects during chemotherapy in advanced colorectal cancer is an independent and reliable prognostic indicator for response and survival.