Hand and foot syndrome is caused by which anticancer drug
**Core Concept**
Hand and foot syndrome, also known as palmar-plantar erythrodysesthesia (PPE), is a common side effect of certain anticancer drugs that cause damage to the skin on the palms of the hands and soles of the feet. This condition is characterized by redness, swelling, and peeling of the skin, which can be painful and interfere with daily activities.
**Why the Correct Answer is Right**
The correct answer is 5-Fluorouracil (5-FU). 5-FU is a pyrimidine analog that works by inhibiting thymidylate synthase, an enzyme involved in DNA synthesis. This inhibition leads to the accumulation of thymine nucleotides and the depletion of thymidine triphosphate, ultimately resulting in cell death. However, the drug's mechanism also involves the production of a toxic metabolite, 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP), which inhibits thymidylate synthase and leads to the formation of DNA-DNA cross-links. These cross-links cause damage to the skin, leading to hand and foot syndrome.
**Why Each Wrong Option is Incorrect**
**Option A:** Capecitabine is a prodrug of 5-FU, and while it can cause hand and foot syndrome, it is not the primary cause of this condition. Capecitabine works by being converted to 5-FU in the body, which then causes the same toxic effects.
**Option B:** Oxaliplatin is a platinum-based chemotherapy agent that works by forming platinum-DNA adducts, leading to cell death. While it can cause neurotoxicity and other side effects, it is not typically associated with hand and foot syndrome.
**Option C:** Bevacizumab is a monoclonal antibody that targets vascular endothelial growth factor (VEGF), preventing angiogenesis and tumor growth. It can cause hypertension, proteinuria, and other side effects, but it is not associated with hand and foot syndrome.
**Option D:** Docetaxel is a taxane that works by stabilizing microtubules and preventing cell division. It can cause neutropenia, alopecia, and other side effects, but it is not typically associated with hand and foot syndrome.
**Clinical Pearl / High-Yield Fact**
Hand and foot syndrome is a common side effect of 5-FU and its prodrugs, such as capecitabine. To remember this, use the mnemonic "F-U-C-K" (5-Fluorouracil, Capecitabine, Cisplatin, and Fluorouracil's cousin, Capecitabine).
**Correct Answer:** A. 5-Fluorouracil (5-FU).