American Board of Internal Medicine (ABIM) Certification Practice Exam

When is adjuvant chemotherapy recommended for patients with stage II colon cancer?

1. When there is T1 disease

2. In cases of inadequate lymph node sampling

3. Only for low risk patients

4. For stage I disease only

The correct answer is: In cases of inadequate lymph node sampling

Adjuvant chemotherapy is recommended for patients with stage II colon cancer particularly in cases of inadequate lymph node sampling. The rationale behind this is rooted in the importance of the lymph node examination in staging and risk stratification. In stage II colon cancer, the overall prognosis is generally favorable, but certain high-risk features can necessitate the use of adjuvant chemotherapy to mitigate the potential for recurrence. A key factor in determining the appropriateness of adjuvant chemotherapy is the thoroughness of the lymph node evaluation. If the lymph nodes removed during surgery are inadequate (typically fewer than 12 nodes examined), there is a concern regarding the accuracy of staging and a higher potential for undetected metastasis. Consequently, the use of adjuvant chemotherapy can be justified in such scenarios to reduce the risk of recurrence and improve outcomes. The other options do not align with current clinical guidelines. For instance, T1 disease typically indicates a lower stage where adjuvant therapy is not indicated. Similarly, the idea of restricting adjuvant chemotherapy to only low-risk patients fails to acknowledge that even some high-risk characteristics in stage II patients may warrant treatment. Lastly, adjuvant chemotherapy is not relevant for stage I disease, which is usually treated surgically alone due to