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: Surgery
[{'content': 'Prognosis of melanoma depends ona) Stageb) Depth of melanoma of biopsyc) Duration of growthd) Site \nSelect and explain. \nA. acd, B. bcd, C. abd, D. ab', 'role': 'user'}, {'content': "Answer: C \nExplanation: Prognosis of melanoma depends most importantly on staging. The most current staging system (of AJCC) takes into account following factors\n\n\ndepth of invasion (Breslow's thickness) - this is the single most important prognostic factor\nulceration - presence of ulceration carries worse prognosis.\nlymph node status\nsatellite lession\ndistant metastasis\n\nOther prognostic factor (not included in staging)\n\nSite or anatomic location - people with lesion of the extermities have a better prognosis than people with melanomas of the head & neck or trunk. (feet and mucous membrane also have poor prognosis- Harrison)\nGender -females have better prognosis than males\nHistologic type - Lentigo maligna has best prosnosis & acral lentiginous worst.\nOld age especially > 60 have poorer prognosis.\n\nAlso know\nThe factor that most closely correlates with local recurrence is primary tumor ulceration (Sabiston 18/e p774)", 'role': 'assistant'}]