Objective:

To examine how diagnostic pathways influence disease stage at presentation, treatment intensity, survival outcomes, and healthcare expenditures in older adults diagnosed with colorectal cancer (CRC).

Approach:

• Study Design: Utilized SEER-Medicare data to identify patients aged 66–90 diagnosed with first primary colon and rectum/rectosigmoid cancer from 2005 to 2019.
• Data Sources: SEER aggregates data from 18 registries covering ~47.9% of the U.S. population, linked with Medicare claims data.
• Cohort Selection: Included patients continuously enrolled in Medicare Parts A and B for 12 months before or after diagnosis, excluding those with incomplete staging or benign cancers.
• Route to Diagnosis: Categorized patients based on their route to diagnosis (Routine Screening, Inpatient/Outpatient Visits, Emergency route) using a validated algorithm.

Key Findings:

• Colorectal cancer is a significant public health burden, particularly among individuals aged 50 and older.
• Screening uptake has increased among younger adults, but one-third of CRC cases still present emergently.
• Missed screening opportunities contribute to advanced-stage diagnoses and worse outcomes.

Interpretation:

Limitations:

• The study focused only on Medicare beneficiaries, which may limit generalizability to other populations.
• Data limitations in capturing complete patient demographics and socioeconomic factors may affect findings.

Conclusion: