Ovarian Tumors in Children: They Happen

When people think of ovarian tumors, they most commonly think of women. However, ovarian tumors (also known as neoplasms) can also occur in children. Tumors are abnormal masses of tissue that form when cells in a certain area of the body reproduce at an increased rate.

The ovaries are a pair of glands that contain the eggs (female reproductive cells) and produce female hormones. Hormones are natural chemicals produced by the body and released into the blood that have a specific effect on tissues in the body.

Most ovarian tumors in children are known as germ cell tumors. As the name implies, these are tumors derived from germ cells. Germ cells are any cells that give rise to other cells that fuse with another cell during fertilization. These types of tumors can be cancerous (malignant) or non-cancerous (benign). Cancer is any of a large group of malignant diseases characterized by an abnormal, uncontrolled growth of new cells in one of the body organs or tissues.

The second most common type of ovarian tumor in children is the surface epithelial neoplasm, although information about them in children is limited. These tumors can also be cancerous or non-cancerous and arise from the epithelial surface of the ovaries, endometrial tissue (lining of the uterus) that is out of place, of Fallopian tube tissue. The uterus is a hollow organ in a female's body where the egg is implanted and the baby develops. Fallopian tubes are two structures that serve as passageways from the ovary to the uterus.

In an upcoming issue of the American Journal of Surgical Pathology, researchers reported detailed findings on surface epithelial neoplasms in children at the Stanford University School of Medicine between 1974 to 2010. Over that 36 year time frame, the researchers found 69 such tumors in 64 children. In 57.8% of the cases, the tumors were non-cancerous. In 37.5% of cases, the tumors were of borderline/low malignant potential. Only 4.7% of these tumors were malignant but no high-grade tumors (fast growing and aggressive) were found. This is unlike adults, where a high percent of high-grade ovarian tumors are found.

The types of surface epithelial neoplasms in children were classified as serous, mucinous, or mixed (different subtypes combined). The serous tumors are filled with serous fluid, a type of pale yellow and transparent body fluid. The mucinous tumors are made of epithelial cells in which the apical surface is lined with mucin (a gel-like secretion). The apical surface is the part of the cell exposed to the lumen (the inside space). 

Of the 64 children, 17 had follow-up data obtained on average 22 years later. Of these patients, recurrences occurred in about 12% of benign tumors, 33% of borderline/low malignant potential tumors, and 100% of malignant tumors. Recurrences occurred anywhere between 11 to 144 months after initial diagnosis and mostly occurred in the same ovary suggesting that incomplete surgical removal of the tumor was the likely cause of recurrence. Recurrence rates were similar in the 3 subroups (serous, mucinous, mixed). While all children with benign and borderline/low malignant ovarian tumors survived, only half of children with malignant ovarian tumors survived.

The authors noted that although two patients were treated with chemotherapy and one with sterilization procedures, that most cases can be treated by surgically removing the tumor. The researchers advocated for uniform treatment models, conserving the ovary, and trying to preserve fertility in any child with a suspected ovarian surface epithelial lesion.

Suggested reading: Memoir of a Debulked Woman: Enduring Ovarian Cancer

Related blog entries: Ovarian Cancer: Treatment with Avastin

Childhood Tumors: How PET/CT Scans Can Help
 
Reference: Hazard FK, Longacre TA. (2013, in press). Ovarian Surface Epithelial Neoplasms in the Pediatric Population: Incidence, Histologic Subtype, and Natural History. Am J Surg Pathol..