Nationwide incidence, treatment, and outcomes of patients 80 years and older with rectal adenocarcinomas: Analysis of 5,076 patients.

Abstract

723 Background: Elderly patients have been underrepresented in randomized clinical trials of rectal cancer, and the value and tolerance of treatment options in this population remain unclear. We used the National Cancer Data Base (NCDB) to assess the incidence, treatment patterns, and overall survival (OS) outcomes of patients 80 years or older with newly diagnosed non-metastatic rectal adenocarcinomas. Methods: 5076 patients 80 years and older diagnosed with non-metastatic rectal adenocarcinomas from 2004 to 2013 were identified. Univariable and multivariable (MVA) analysis were performed to identify patient, tumor, and treatment characteristics associated with receipt of standard of care therapy (SOCT) and factors predictive of OS. SOCT was defined as surgical resection for Stage I patients and receipt of neoadjuvant therapy followed by surgical resection for Stage II/III patients. Kaplan-Meier curves were generated to assess the effect of stage and treatment received on overall survival. Results: At presentation, 935 (18.5%) were TXN0, 1557 (30.8%) were Stage I, 1552 (30.6%) were Stage II, and 1,032 (20.1%) were Stage III. The rates of patients receiving no therapy were: 29.6% for TXN0, 22.6% for Stage I, 16.5% for Stage II, and 12.2% for Stage III. The rates of patients not receiving SOCT were: 22.6% for Stage I, 51.4% for Stage II and 39.4% for Stage III cases. Survival was significantly worse for patients not receiving standard of care therapy: Stage I (52.1% receiving SOCT vs. 7.6% not receiving SOCT; p < 0.01), Stage II (49.8% receiving SOCT vs. 14.5% not receiving SOCT; p < 0.01), and Stage III (47.5% receiving SOCT vs. 10.2% not receiving SOCT; p < 0.01). On MVA of patient, tumor, and treatment variables, receipt of SOCT was associated with improved OS for the entire cohort (p < 0.01) and when examined by stage (p < 0.01). Conclusions: In this nationwide sample of patient’s ≥ 80 years old with rectal cancer, there was a high rate of patients receiving no therapy. Those that did receive standard therapy achieved reasonable outcomes, suggesting avoidance of guideline care in this population should not be advised.