In ovarian cancer there are different types, each with different degrees of malignancy, but the most important prognostic factor is the extent of the tumor at diagnosis. The types of ovarian cancer are named for the cells from which the cancer derived. They can also be classified in two groups: primary and secondary tumors. To identify the type of tumor, a laparotomy (surgery of the abdominal cavity) must necessarily be conducted.
Although their classification is very complex, the most common are epithelial tumors (90% of cases). The other cases include germ cell tumors and very rarely stromal tumors.
- Serous: serous adenocarcinomas are the most common ovarian cancers. At the time of diagnosis generally, they have an average size of 15 cm, and in most cases are bilateral.
- Mucinous: represents 15% of malignant ovarian tumors. Its name derives from cell that produce mucin (mucus species), which extends throughout the peritoneal cavity. They appear in younger women, usually diagnosed in early stages and have a better prognosis than serous.
- Endometrioid: they have a solid and dark appearance. In half the cases they are bilateral and represent 15-25% of ovarian cancers.
- Clear cell: its name derives from the cells that form it because they have a clear appearance. 5% of ovarian cancers are this type. They are bilateral in 20-40% of cases.
- Borderline tumors: some epithelial tumors have low malignancy. Their main feature is that they do not invade the ovary in depth. Usually they occur in young women and progress slowly. Prognosis is favorable in most cases.
Germ cell tumors
They appear in the second or third decade of life. They are very sensitive to chemotherapy, and surgical treatment is more conservative than in the case of epithelial tumors. The most common varieties are teratomas and dysgerminomas.
Sex cord stromal tumors
These are the least common types, and they include:
- Granulosa: they are more common in postmenopausal women, and produce estrogen (female hormone), so they may have early symptoms because the increase in estrogen, as the absence of menstruation or, conversely, heavy bleeding, increased endometrial thickness. Because they express early symptoms, they are usually diagnosed before progressing in advanced stages, which improves prognosis.
- Ovarian Thecoma: usually benign, and about half produce estrogen and / or androgen (mainly male hormone), which may facilitate early diagnosis, as in the case of tumors derived from the granulosa.
- Androblastoma or sertoli-Leydig cell tumor (SLCT): are usually benign and reproduce testicular elements therefore half of these tumors can produce androgens, and this may lead to symptoms such as: acne, enlargement of the clitoris, decreased menstrual bleeding …,so they are the leading cause of virilization (masculinization) syndrome of ovarian origin.
Secondary ovarian malignancies
Ovarian cancer can occur as a result of other types of cancer, such as carcinomas of the genital tract, gastrointestinal and breast. Malignant cells from these primary tumors spread to the ovary and form a new tumor (metastasis).