Table 1.

Subtypes of ovarian cancer and characteristics of each.

Cancer	Type	Subtype	Grade	Characteristics	References
Ovarian cancer	Epithelial	Serous	High-grade	90% of serous ovarian cancer	[10,12,13,14,15]
				Generally diagnosed in older women
				Present at advanced stages
				Have poor prognosis (10-year survival rate of 30%)
				Originates in the ovary, fallopian tube, and others
				Have TP53 and BRCA mutation
				50% of tumors have homologous recombination deficiencies
			Low-grade	Usually diagnosed in younger women	[10,12,14,16,17]
				Grow slowly
				Have a better prognosis than high-grade serous carcinoma
				Originates in ovary
		Endometrioid	Low-grade	Chemosensitive	[10,18,19]
				Generally diagnosed in the early stage
				Originates in endometriosis
				Has better prognosis
		Mucinous	Low-grade	Most uncommon cancer in epithelial ovarian cancer	[10,19,20,21]
				Associated with metastasis from the gastrointestinal tract
				Most patients are diagnosed with stage I
		Clear cell	Low-grade	Relatively have a good prognosis	[1,10,19,22]
				Generally diagnosed in the early stage
				Have resistance to platinum-based chemotherapy in advanced stage
	Non-epithelial	Germ cell	-	3% of ovarian cancer	[1,10,23,24]
				Have obvious makers of tumor
				Diagnosed at a young age (10~30 years old)
				Histologically like men’s germ cell tumors in the testes
		Sex cord-stromal	-	Under 2% of ovarian cancer	[25,26]
				Generally diagnosed in the early stage
				Smoking decreases the risk of the tumor
				Rarely have malignance