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': 'Which of the following is the most radiosensitive ovarian tumors: \nSelect and explain. \nA. Dysgerminoma, B. Dermoid cyst, C. Serous cystadenoma, D. Endodermal sinus tumour', 'role': 'user'}, {'content': 'Answer: A \nExplanation: “Below the age of 20 years 60% of the tumours are of germ cell origin and in girls under the age of 10 years almost 85% are of germ cell origin and are invariably malignant.”\n“Dysgerminoma is the most common malignant germ cell tumour accounting for about 40% of all ovarian cancers of germ cell origin.”\n“Dysgerminomas are the most common malignant germ cell tumours of the ovary and have been considered the female - equivalent of seminoma.”\nMost common germ cell tumour of ovary is dermoid cyst (mature teratoma). It is benign in nature.\nRemember:\n• Most common ovarian tumour (overall) – Epithelial cell tumour.\n• Most common tumour in young woman is – Germ cell tumour.\xa0\n• Most common malignant tumour of ovary – Serous cystadenocarcinoma.\n• Most common benign tumour of ovary (overall) – Dermoid cyst.\xa0\n• Most common benign epithelial tumor of ovary – Serous cystadenoma.\xa0\n• Most common germ cell tumour – Mature teratoma (Dermoid cyst).\n• Most common malignant GCT – Dysgerminoma.\n• Most common ovarian tumour in pregnancy (but in remains undiagnosed) – Serous cystadenoma.\n• Most Common benign tumour diagnosed in pregnancy – Dermoid cyst.\n• Overall most common ovarian tumour diagnosed in pregnancy – Dermoid cyst.\n• Most common malignant ovarian tumor detected during pregnancy – Dysgerminoma.\n• Germ cell Tumor with best pregnosis Dyserminoma\n• Germ cell tumor with worst prognosis- endodermal sinus tumor\n• Germ cell tumor which has maximum bilaterality– Dysgerminoma\n• Germ cell tumor which presents as accute abdomen- Endodermal Sinus Tumor\n• Most common ovarian tumour to undergo torsion during pregnancy – Dermoid cyst.\n• Most common ovarian tumour to involve opposite ovary by metastasis – Granulosa cell tumour.\n• Most radiosensitive ovarian tumour – Dysgerminoma.\n• Most rapidly growing ovarian tumour – Yolk sac Tm- (Endodermal Sinus Tumor)\n• Most connective tissue tumour – Fibroma.\nOvarian Tumour: Causing:\n• Pseudomyxoma peritonei – Mucinous cystadenoma.\n• Meig’s syndrome – Ovarian fibroma\n• Pseudomeig’s syndrome: – Brenner’s tumour\n– Granulosa cell tumour\n– Thecoma\n• Ovarian tumour associated with hyperpyrexia and hypercalcemia – Mesonephroid tumour.\n• Ovarian tumour arising from epithelium of urinary tract – Brenner Tm\n• Feminizing tumours: – Granulosa cell tumour\n– Theca cell tumour\n– Fibromas\n• Virilising tumour: – Androblastoma\n– Hilus cell Tm\n– Gynadroblastoma\n– Adrenal cortical tumour\n• Largest benign ovarian Tm – Mucinous cyst adenoma\n• Mucinous tumours are associated with: – Dermoid cyst (MBD)\n– Brenner’s tumour\n• Tumour with lymphocytic infilteration:', 'role': 'assistant'}]