This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Transplantation, Subject name: Surgery
What is the primary toxicity of doxorubicin (Adriamycin)? 
Select and explain. 
A. Cardiomyopathy, B. Pulmonary fibrosis, C. Peripheral neuropathy, D. Uric acid nephropathy
A: Cardiomyopathy
Answer: A: Cardiomyopathy 
Explanation: Doxorubicin, an antibiotic derived from Streptomyces species, has activity against sarcomas and carcinomas of the breast, liver, bladder, prostate, head and neck, esophagus, and lung. Its major side effect is production of a dilated cardiomyopathy. Patients receiving this agent should have echocardiography before and after treatment in order to monitor potential cardiac toxicity.