Treatment approaches and survival outcomes in elderly colorectal cancer patients: a single-center comparative study

Background: Geriatric patients account for nearly half of new colorectal cancer (CRC) cases. This study compares clinicopathological features, treatments, outcomes, and frailty in elderly (≥ 70) and younger (< 70) CRC patients at our center.

Materials and methods: Patients diagnosed with non-metastatic or de novo metastatic CRC between January 2015 and April 2024 were included. Demographic, pathological, and survival data were retrospectively collected. Analyses were performed using SPSS version 25, with statistical significance set at P < 0.05.

Results: Of the 414 non-metastatic CRC patients, 26.6% were aged ≥ 70. Elderly patients received less perioperative chemotherapy (60% vs. 81.6%, P < 0.001) and had more dose reductions (41.6% vs. 19.2%, P < 0.001). Frailty reduced perioperative chemotherapy in elderly non-metastatic patients (54.5% vs. 92.1%, P < 0.001) but did not affect dose reduction (37.9% vs. 33.3%, P = 0.764) or treatment duration (median 24 weeks for both groups, P = 0.909). In metastatic patients, frailty shortened chemotherapy duration (9.5 vs. 15.5 weeks, P = 0.129). Elderly patients had lower 5- and 8-year overall survival (OS) rates (64.7%, 60.1% vs. 83.0%, 78.8%, P = 0.004). In the de novo metastatic cohort (135 patients), age did not affect OS (19.4 vs. 17.3 months, P = 0.590) or PFS (9.8 vs. 7.5 months, P = 0.209). Rectal cancer (HR: 2.751, P = 0.005) and early chemotherapy termination (HR: 4.138, P < 0.001) worsened OS in non-metastatic CRC, while absence of RAS (HR: 2.043, P = 0.047), BRAF mutations (HR: 8.263, P = 0.010), and metastasectomy (HR: 3.650, P = 0.036) improved OS in metastatic CRC.

Conclusion: Age does not independently worsen CRC survival, though early chemotherapy discontinuation impacts outcomes. Reduced-dose chemotherapy or monotherapy can help minimize adverse effects in elderly patients.