Baseline anaemia increases locally advanced rectal cancer mortality in older patients undergoing preoperative chemoradiation

Abstract

Purpose: The median diagnosis age of rectal cancer (RC) is 70 years old. The standard of care for locally advanced RC (LARC) is preoperative chemoradiation (CRT) followed by surgery. Anaemia is a frequent condition in older patients but is not a pure consequence of ageing. Methods: The patients aged 65 years or over, with clinical stage II/III LARC, and treated with preoperative concurrent CRT were retrospectively reviewed. Baseline haemoglobin (Hb) levels were collected. Results: One hundred and seven patients enrolled in this study, but 17 were excluded in relation with treatment disruption. Fifty-seven (63.3%) males and 33 (36.7%) females completed preoperative CRT whose median age at diagnosis was 73. Twenty-five (27.8%) patients presented with anaemia at rectal cancer diagnosis, and median Hb was 13.5 g/dL (IQR = 1.45) and 11.2 g/dL (IQR = 1.35), for non-anaemic and anaemic patients, respectively. For the enrolled older population, only 2 patients reported acute grade 3 toxicity. Baseline anaemia tended to decrease the LARC-free interval and was associated with a significantly higher hazard of all-cause and LARC mortality, approximately 5 times (HR = 5.25; 95% CI 1.48-18.66) and 10 times (HR = 10.09; 95% CI 2.40-42.48), respectively. Patients older than 75 presented a significantly negative impact on overall survival (OS) and LARC-specific survival (HR = 6.20, 95% CI 2.00-19.22; and HR = 7.61, 95% CI 2.08-27.87, respectively). Conversely, no significant impact was found for age-adjusted Charlson comorbidity index on OS, LARC-specific survival and LARC-free interval. Conclusions: Overall and LARC-specific survival were significantly lower for the baseline anaemic older patients and for those aged 75 years or over.