This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
[{'content': 'Abnormal rise of HCG in a female of reproductive age group may indicate the following malignancy: \nSelect and explain. \nA. Choriocarcinoma, B. Colon carcinoma, C. Serous cystadenoma, D. Teratoma', 'role': 'user'}, {'content': "Answer: A \nExplanation: hCG is composed of and subunits and can be produced as intact hormone, which is biologically active, or as uncombined biologically ine subunits. Ectopic production of intact hCG occurs most often in association with testicular embryonal tumors, germ cell tumors, extragonadal germinomas, lung cancer, hepatoma, and pancreatic islet tumors. Eutopic production of hCG occurs with trophoblastic malignancies. hCG subunit production is paicularly common in lung cancer and pancreatic islet cancer. Ref: Longo D.L., Jameson J.L. (2012). Chapter 100. Paraneoplastic Syndromes: Endocrinologic/Hematologic. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.", 'role': 'assistant'}]