American Board of Internal Medicine (ABIM) Certification Practice Exam

The R-CHOP regimen is a commonly used chemotherapy protocol for the treatment of certain types of non-Hodgkin lymphoma, particularly diffuse large B-cell lymphoma and follicular lymphoma. The components of the R-CHOP regimen consist of rituximab, cyclophosphamide, doxorubicin (also known as hydroxydaunorubicin), vincristine (Oncovin), and prednisone.

Cyclophosphamide is an alkylating agent that plays a crucial role in the R-CHOP regimen. It contributes to the effectiveness of the treatment by interfering with the cancer cell's ability to replicate DNA. This makes it particularly useful in combination with other agents in the regimen to target and kill rapidly dividing cells, which is characteristic of cancer.

In contrast, the other therapies mentioned – imatinib, dabigatran, and cisplatin – do not form part of the R-CHOP regimen. Imatinib is a targeted therapy for specific types of chronic myeloid leukemia and gastrointestinal stromal tumors, dabigatran is an anticoagulant used to prevent blood clots, and cisplatin is a platinum-based chemotherapy agent primarily used in the treatment of testicular cancer and various solid