Clinicopathologic features and prognostic factors for patients with colorectal cancer who are 75 years and older.

Colorectal cancer (CRC) is common and can be considered as a disease of older adults. About one half of the cases were diagnosed in patients over 70 years of age. Decision-making about treatment for these older patients can be complicated by age-related physiological changes, impaired functional status, limited social support, and comorbidities. Many trials excluded patients using an upper limit of 75 years of age. Little is known about prognostic factors in patients who are over this age limit. In this study, we conducted an analysis in the Surveillance, Epidemiology and End Results (SEER) database to identify specific clinicopathologic features and prognostic factors for these vulnerable cancer patients (N= 293,616). They were predominantly female and had more stage I and II diseases in comparison to younger patients. On average, these patients had lower 5-year cause-specific mortality than younger patients (41.98% vs. 63.14%, P<0.001). Gender, marital status, ethnicity, Tumor-Node-Metastasis stage, grade, histologic subtype, tumor size, status of surgery and radiotherapy were all independent prognostic factors for these elderly CRC patients. In particular, surgery could improve prognosis for all CRC patients with the exception of those who are older than 94 years old and with stage III disease. The identified clinicopathologic features and prognostic factor will help guide treatment decision-making for this oldest old subset of patients with CRC.