Certified Tumor Registrar (CTR) Practice Exam

What information does the sequence number provide in a cancer diagnosis?

1. The date of the diagnosis

2. The number of treatment sessions

3. The number of primary tumors the patient has

4. The stage of cancer

The correct answer is: The number of primary tumors the patient has

The sequence number is an essential part of cancer registry data, specifically used to indicate the number of primary tumors a patient has. It helps registrars and researchers differentiate between multiple tumors in a single patient, particularly when patients have more than one tumor at different sites or when tumors develop independently over time. This systematic approach allows for accurate tracking and reporting of cancer cases, which is critical for obtaining accurate statistics, understanding population health, and determining treatment outcomes. Each primary tumor that is diagnosed will receive its own sequence number, making it easier to analyze and interpret patterns of disease distribution and associated factors effectively. While the date of diagnosis, number of treatment sessions, and stage of cancer are all critical components of a cancer registry, they do not pertain to the purpose of the sequence number. The sequence number focuses specifically on counting and identifying distinct primary tumors in the patient's medical history.