<s>[INST] context: “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.”
“Dysgerminoma is the most common malignant germ cell tumour accounting for about 40% of all ovarian cancers of germ cell origin.”
“Dysgerminomas are the most common malignant germ cell tumours of the ovary and have been considered the female - equivalent of seminoma.”
Most common germ cell tumour of ovary is dermoid cyst (mature teratoma). It is benign in nature.
Remember:
• Most common ovarian tumour (overall) – Epithelial cell tumour.
• Most common tumour in young woman is – Germ cell tumour. 
• Most common malignant tumour of ovary – Serous cystadenocarcinoma.
• Most common benign tumour of ovary (overall) – Dermoid cyst. 
• Most common benign epithelial tumor of ovary – Serous cystadenoma. 
• Most common germ cell tumour – Mature teratoma (Dermoid cyst).
• Most common malignant GCT – Dysgerminoma.
• Most common ovarian tumour in pregnancy (but in remains undiagnosed) – Serous cystadenoma.
• Most Common benign tumour diagnosed in pregnancy – Dermoid cyst.
• Overall most common ovarian tumour diagnosed in pregnancy – Dermoid cyst.
• Most common malignant ovarian tumor detected during pregnancy – Dysgerminoma.
• Germ cell Tumor with best pregnosis Dyserminoma
• Germ cell tumor with worst prognosis- endodermal sinus tumor
• Germ cell tumor which has maximum bilaterality– Dysgerminoma
• Germ cell tumor which presents as accute abdomen- Endodermal Sinus Tumor
• Most common ovarian tumour to undergo torsion during pregnancy – Dermoid cyst.
• Most common ovarian tumour to involve opposite ovary by metastasis – Granulosa cell tumour.
• Most radiosensitive ovarian tumour – Dysgerminoma.
• Most rapidly growing ovarian tumour – Yolk sac Tm- (Endodermal Sinus Tumor)
• Most connective tissue tumour – Fibroma.
Ovarian Tumour: Causing:
• Pseudomyxoma peritonei – Mucinous cystadenoma.
• Meig’s syndrome – Ovarian fibroma
• Pseudomeig’s syndrome: – Brenner’s tumour
– Granulosa cell tumour
– Thecoma
• Ovarian tumour associated with hyperpyrexia and hypercalcemia – Mesonephroid tumour.
• Ovarian tumour arising from epithelium of urinary tract – Brenner Tm
• Feminizing tumours: – Granulosa cell tumour
– Theca cell tumour
– Fibromas
• Virilising tumour: – Androblastoma
– Hilus cell Tm
– Gynadroblastoma
– Adrenal cortical tumour
• Largest benign ovarian Tm – Mucinous cyst adenoma
• Mucinous tumours are associated with: – Dermoid cyst (MBD)
– Brenner’s tumour
• Tumour with lymphocytic infilteration: [/INST] question: Which of the following is the most radiosensitive ovarian tumors: | options: A: Dysgerminoma B: Dermoid cyst C: Serous cystadenoma D: Endodermal sinus tumour | answer: A </s>