Overview of ovarian tumors

Last updated: May 24, 2023

Summary

The ovaries consist of different types of tissue (epithelial, germ cells, and sex cord tissue), which may give rise to benign or malignant tumors. Epithelial ovarian tumors are the most common tumor subtype.

For information about ovarian cancer, see “Ovarian cancer”.

Classification of ovarian tumors

Epithelial ovarian tumors
- Arise from ovarian surface epithelium
- Most commonly benign
Germ cell ovarian tumors
- Arise from the primordial germ cells (e.g., oocytes)
- Can be benign or malignant
Sex cord and stromal ovarian tumors
- Arise from sex cord cells (e.g., Sertoli or granulosa cells) or stromal cells (e.g., fibroblasts or primitive gonadal stroma)
- Can be benign or malignant

Cellular origins of ovarian tumors

Epithelial ovarian tumors

Frequency ^[3]
- Most common benign and malignant ovarian tumor subtype
- Epithelial tumors account for ∼ 90% of all ovarian malignancies
Histological classification
- Benign: lack hyperproliferative and invasive behavior
- Borderline ovarian tumors: a histopathological term that describes an ovarian tumor of low malignant potential that expresses cytologic features of malignancy without frank invasion
- Malignant: evidence of invasion
Clinicopathological classification ^[4]
- Type I ovarian tumors: low-grade, indolent tumors that typically manifest as large, unilateral, cystic neoplasms
  - Histologic subtypes include low-grade serous, endometrioid, clear cell, mucinous carcinomas, and malignant Brenner tumors
  - Account for ∼ 10% of ovarian cancer deaths
  - Associated with low levels of chromosomal instability
  - p53 mutations are uncommon.
- Type II ovarian tumors: high-grade, aggressive tumors that typically involve both ovaries and are diagnosed at an advanced stage
  - Histologic subtypes include high-grade serous, carcinosarcoma, and undifferentiated carcinoma
  - Account for ∼ 90% of ovarian cancer deaths
  - Associated with high levels of chromosomal instability
  - p53 mutations are common

Types of epithelial ovarian tumors
Type		Cystadenoma		Brenner tumor ^[5]	Cystadenocarcinoma		Endometrioid carcinoma ^[3]^[6]	Clear cell tumors ^[3]^[7]
Type		Ovarian serous cystadenoma	Ovarian mucinous cystadenoma	Brenner tumor ^[5]	Serous	Mucinous ^[8]	Endometrioid carcinoma ^[3]^[6]	Clear cell tumors ^[3]^[7]
Classification		Benign			Malignant
Epidemiology		Most (serous) and second most common (mucinous) benign ovarian tumor		Rare Peak age: 40–60 years	Most common malignant ovarian tumor	Rare Can also be metastatic from GI malignancies (e.g., of the appendix)	10% of epithelial tumors Concomitant endometrial carcinoma in 10–15% of cases	5–10% of epithelial tumors Most commonly occur in perimenopausal women
Epidemiology				Rare Peak age: 40–60 years	Most common malignant ovarian tumor		Associated with endometriosis ^[9]
Clinical features		Typically asymptomatic Symptoms of abdominal displacement may be present (e.g., pain, ↑ urinary frequency)				Acute abdominal pain Pseudomyxoma peritonei ^[10] Rupture of a mucinous cystadenoma or cystadenocarcinoma leading to the spread of tumor cells throughout the peritoneum. Mucinous cells cause gelatinous ascites and intraabdominal adhesions.	Pelvic pain Symptoms of abdominal displacement may be present (e.g., pain, ↑ urinary frequency) Abnormal vaginal bleeding
Ultrasound appearance		Unilocular cystic mass Absent flow on Doppler	Large, multilocular cystic tumor	Mostly small tumors with a solid component and calcifications Absent or only minimal flow on Doppler	Cystadenocarcinomas are often bilateral (serous >> mucinous)		Mostly large, unilateral, solid or multilocular-solid tumor with papillary projections	Large (up to 30 cm in diameter), cystic/solid unilateral masses
Ultrasound appearance		Unilocular cystic mass Absent flow on Doppler	Large, multilocular cystic tumor		Tumor with mixed cystic/solid components and heterogeneous texture May contain papillary projections and/or thick septations	Similar to mucinous cystadenoma Additional solid components and signs of malignancy (e.g., invasion of adjacent structures) may be present Mural thickening
Pathology	Gross examination	Cysts with watery fluid	Smooth or bosselated appearance Cyst is loculated; loculi contain gelatinous material	Encapsulated, pale yellow solid tumor	Similar to serous cystadenoma	Cysts filled with mucoid material, cellular debris, and/or blood	Possible appearances are: Smooth surface with cystic spaces filled with blood-stained fluid Completely solid with necrosis/hemorrhage	Endometriosis-associated tumors are filled with chocolate-colored fluid
Pathology	Histology	May contain small papillary projections Psammoma bodies Cyst is lined by serous epithelial cells (similar to the epithelium of fallopian tubes)	Cyst is lined by columnar epithelium that secretes thick mucus (similar to the epithelium of cervix)	Similar to transitional cells of the bladder (urothelium) Circular patches of cells with coffee bean nuclei	Tumor cells with papillary structures and small cytoplasm Psammoma bodies are a typical feature .	Cystic or colloid type, depending on intracellular or extracellular mucin deposition Cystic type: > 50% of intracellular mucin in ≥ 90% of tumor cells Colloid type: large quantities of extracellular mucin (≥ 50% of tumor volume)	Characteristic confluent glandular/expansile pattern Tightly packed, back-to-back glands lined with tumor cells Absent intervening stroma	Variable appearance: tubulocystic, papillary, and solid
Tumor marker		CA-125

CA-125 is used as a tumor marker for epithelial ovarian cancer but can also be elevated in endometriosis, cirrhosis, and malignancies (e.g., uterine leiomyoma).

Most ovarian tumors are benign, not malignant. High-grade serous carcinoma of ovary Serous papillary cystadenoma of the ovary with Psammoma bodies Ovarian mucinous cystadenoma Brenner tumor

Ovarian germ cell tumors

Frequency: ∼ 5% of all ovarian tumors ^[3]
Subtypes are determined by structural differentiation
- Extraembryonic differentiation: yolk sac tumor
- Somatic differentiation: teratoma
- No differentiation: dysgerminoma

Types of ovarian germ cell tumors
Type	Teratoma			Yolk sac tumor of the ovary (endodermal sinus tumor) ^[11]	Dysgerminoma ^[12]	Nongestational choriocarcinoma ^[13]	Embryonal carcinoma of the ovary
Type	Dermoid cysts (mature cystic teratoma)	Struma ovarii (mature teratoma) ^[14]	Immature teratoma ^[15]	Yolk sac tumor of the ovary (endodermal sinus tumor) ^[11]	Dysgerminoma ^[12]	Nongestational choriocarcinoma ^[13]	Embryonal carcinoma of the ovary
Classification	Benign		Malignant, aggressive
Epidemiology	Most common of all germ cell tumors (90% of all cases) Most common ovarian tumor in women < 30 years ^[16]	∼ 5% of all ovarian teratomas ^[17]	Rare Peak age: women < 20 years of age ^[18]	Occurs mainly in children and adolescents ^[18]	Most common malignant ovarian germ cell tumor in adolescents and young women ^[18]	∼ 5% of all malignant germ cell tumors ^[18]	Occurs mainly in children and adolescents
Clinical features	Mostly asymptomatic		Unspecific symptoms, including: Painful abdominal mass Amenorrhea	Rapid growth; acute onset of symptoms (pelvic mass and pain)			Precocious puberty Menstrual irregularities
Clinical features	Larger tumors may cause: ↑ Abdominal girth Pressure symptoms (e.g., ↑ urinary frequency) Lower abdominal pain	Symptoms of hyperthyroidism Palpable lower abdominal mass and pain					Precocious puberty Menstrual irregularities
Ultrasound appearance	Heterogeneous mass Hyperechoic nodule Echogenic shadowing Absent internal vascularity and/or fluid-fluid levels	Multilocular solid appearance Struma pearl may be present.	Large tumor with a solid component Solid component arises from the wall of the cyst and makes up ≥ 15% of total cyst size; contains smaller, fluid-filled cysts (e.g., blood, mucus). Small areas of calcification	Well vascularized tumor Contains a slightly hyperechoic solid component with an irregular, but still fine-textured appearance No acoustic shadowing	Large, solid, well- vascularized, multilobulated tumor that is well-defined relative to its surroundings Heterogeneous internal echogenicity	Well-vascularized mass with inhomogeneous texture Irregular contour Ovarian crescent sign may be present	Large, solid, well-defined tumor
Histopathology	Contains somatic tissue (e.g., hair, teeth, sebaceous glands) from any of the three embryonic germ layers: Endoderm Mesoderm Ectoderm	Endodermal differentiation into thyroid tissue ^[17]	Composed of immature neuroectodermal tissue	Macroscopic appearance: yellow, friable mass (due to hemorrhage) Schiller-Duval bodies (resemble glomeruli on microscopy) ^[19]	Equivalent to seminoma (e.g., presence of fried egg cells; see “Seminoma” for more details)	Cytotrophoblasts/syncytiotrophoblasts without chorionic villi	Syncytiotrophoblast-like tumor cells Aggregates of primitive embryonal cells Glandular or papillary pattern
Tumor markers	None		LDH (rare) ^[20]		LDH ^[21] hCG (rare: ∼ 5%)	hCG	hCG AFP
Tumor markers	None		AFP (rare) ^[22] CA-125 (rare)	AFP ^[23]	LDH ^[21] hCG (rare: ∼ 5%)	hCG	hCG AFP
Risk of malignant transformation	∼ 1% (usually to squamous cell carcinoma) ^[24]	Very rarely into thyroid carcinoma	N/A

Dermoid cyst (mature teratoma) Mature teratoma of the ovary Struma ovarii Dysgerminoma Schiller-Duval body

Sex cord-stromal tumors of the ovary

Frequency: < 5% of all ovarian tumors ^[25]

Types of sex cord-stromal tumors of the ovary
Type		Ovarian fibroma ^[26]	Theca cell tumor (thecoma) ^[27]	Sertoli-Leydig cell tumor ^[28]^[29]^[30]^[31]	Granulosa cell tumor ^[28]^[32]^[33]
Classification		Benign		Usually benign	Malignant
Epidemiology		Peak age: postmenopause ^[34]		Rare Peak age: 30–40 years	Most common type of sex cord-stromal malignancy (∼ 90%) Peak age: 50–55 years
Clinical features		No hormonal activity Lower abdominal discomfort and/or a pulling-sensation in the inguinal area May be associated with Meigs syndrome: ascites and pleural effusion in association with a benign ovarian tumor; surgical removal of the tumor leads to complete resolution of symptoms. ^[35]	Abnormal postmenstrual bleeding due to estrogen production	Symptoms of excessive androgens and/or estrogen production ↑ Testosterone Virilization, hirsutism, acne, temporal balding Amenorrhea, clitoral enlargement, ↓ fertility ↑ Estrogen Menstrual bleeding abnormalities Endometrial polyps and hyperplasia	Symptoms caused by estrogen and/or progesterone secretion Adult subtype: menstrual irregularities (e.g., postmenopausal bleeding, endometrial hyperplasia with metrorrhagia) Juvenile subtype: precocious puberty Breast tenderness Associated with increased risk of endometrial cancer
Ultrasound appearance		Round or oval solid tumor with minimal to moderate vascularization Regular to slightly irregular internal echogenicity Cystic spaces may be present.	Ultrasound appearances include: Well-defined hypoechoic, solid mass with clear margins Echogenic mass with distal acoustic attenuation Anechoic lesion with through-transmission Visible endometrial thickening (secondary to hyperestrogenism)	Most commonly between 5 and 15 cm in diameter Large papillary projections may be visible.	Typically, large tumor with multilocular solid appearance with > 10 small locules Typically mixed or low level echogenicity
Pathology	Gross examination	Smooth, lobulated Cut surface: chalky, firm, yellow-to-white color	Solid yellow-orange tumor	Small, yellow-brown tumor	Tan/yellow color Encapsulated; smooth lobulated surface, possibly with areas of necrosis/hemorrhage
Pathology	Histology	Clusters of spindle-shaped cells (fibroblasts)	Ovarian stromal cells filled with lipids on microscopy	Seminiferous-like tubules lined by Sertoli cells and Reinke crystals	Call-Exner bodies: granulosa cells arranged in clusters surrounding a central cavity with eosinophilic secretions, resembling primordial follicles
Tumor markers		None			Inhibin

Call-Exner bodies are characteristic of Granulosa cell tumors: “Call your Ex and Grandparents!”

Call-Exner bodies

Start your trial, and get 5 days of unlimited access to over 1,100 medical articles and 5,000 USMLE and NBME exam-style questions.

Start free trial

Evidence-based content, created and peer-reviewed by physicians. Read the disclaimer