Administration of adjuvant chemotherapy in older patients with Stage III colon cancer: an observational study

According to established guidelines, patients with Stage III colon cancer should receive adjuvant chemotherapy. However, a significant proportion do not. This study assessed factors associated with the administration of adjuvant chemotherapy and causes of death.

Patients with Stage III colon cancer who underwent surgery between 2000 and 2009 were selected from two hospitals in the Netherlands. Patient characteristics including comorbidities and treatment preferences, tumour characteristics and follow-up were extracted from the medical records. The patient and tumour characteristics of patients who did receive chemotherapy were compared with those who did not using chi-squared analysis. Differences between the groups in causes of death were recorded together with the duration of follow-up.

A total of 348 patients were included. The median age was 73 years (range 33-93). Over half of the patients received adjuvant chemotherapy (50.6%). Patients who did not receive adjuvant chemotherapy were significantly older (P < 0.001), had more comorbidities (P < 0.001) and were more often living alone (P < 0.001). Patients who received no adjuvant chemotherapy had a reduced overall survival, and the cause of death was more often attributed to other causes (60%) than colon cancer (40%). For patients who received chemotherapy, the cause of death was usually attributed to colon cancer (71%).

Patients who did not receive adjuvant chemotherapy had a worse overall survival and the majority died due to other causes than colon cancer. In our aging society it will become even more important to develop tools to estimate remaining life expectancy in order to improve the selection of older patients for adjuvant treatments.