Radiotherapy of rectal cancer in elderly patients: Real-world data assessment in a decade

There is paucity of data on the efficacy and toxicity of radiotherapy in rectal cancer (RC) elderly patients. The objective was to identify management strategies and resulting outcomes in RC patients ≥70 years undergoing radiotherapy.

A retrospective study included consecutive RC patients ≥70 years undergoing rectal radiotherapy.

From 2004-2015, 340 RC patients underwent pre-operative (n = 238; 70%), post-operative (n = 41, 12%), or exclusive (n = 61, 18%) radiotherapy, with a median age of 78.5 years old (range: 70-96). Radiotherapy protocols were tailored, with 54 different radiotherapy programs (alteration of the total dose, and/or fractionation, and/or volume). Median follow-up was 27.1 months. Acute and late grade 3-4 radio-induced toxicities were reported in 3.5% and 0.9% of patients. Metastatic setting (OR = 6.60, CI95% 1.47-46.03, p = 0.02), exclusive radiotherapy (OR = 5.08, CI95% 1.48-18.21, p = 0.009), and intensity-modulated radiotherapy (OR = 6.42, CI95% 1.31-24.73, p = 0.01) were associated with grade ≥3 acute toxicities in univariate analysis. Exclusive radiotherapy (OR = 9.79, CI95% 2.49-43.18, p = 0.001) and intensity-modulated radiotherapy (OR = 12.62, CI95% 2.05-71.26, p = 0.003) were independent predictive factors of grade ≥3 acute toxicities in multivariate analysis. A complete pathological response was achieved in 12 out of 221 pre-operative patients (5.4%). Age, tumor stage, and surgery were independent predictive factors of survival in multivariate analysis. At end of follow-up, 7.1% of patients experienced local relapse.

Radiotherapy for RC in elderly patients appeared safe and manageable, perhaps due to the tailoring of radiotherapy protocols. Tailored management resulted in acceptable rate of local tumor control.