Medical Mystery: Her fibroid only seemed typical

A woman in her 30s, who had one child and hoped for another baby, was being monitored by her gynecologist for the last two years. Her problem: a uterine fibroid that had grown to the size of a grapefruit.

Uterine fibroids (leiomyomas) are the most common pelvic tumor in women, affecting between 15 percent and 25 percent of women in their childbearing years. Although the uterus is by far the most common location for these benign tumors, they can occur elsewhere, such as the skin and colon.

Most fibroids are small and can be left alone, as many shrink on their own. But when they grow, women can experience pelvic pressure or pain, heavy or prolonged menstrual bleeding and anemia, and have trouble getting pregnant.

At that point, surgical options usually need to be considered.

Because our patient wanted to have another child, a myomectomy (removal of only the fibroid) as opposed to a hysterectomy (removal of entire uterus) was undertaken.

As with any other surgical procedure or biopsy, after being removed the uterine fibroid was sent to the pathology lab for further evaluation. Pathologists are physicians who examine blood samples, fluids, and tissues to help make the proper diagnosis and ensure the right treatment.

Under the microscope, most uterine fibroids consist of bland, spindled cells with pink cytoplasm, features typical of benign, smooth muscle cells.

Our patient's fibroid did have some of those features - plus some far more unusual ones.

The microscopic findings observed in our patient's fibroid suggested a syndrome termed hereditary leiomyomatosis and renal cell cancer syndrome.

These patients typically have multiple fibroids - in men, they occur in the skin, and in women, the uterus and the skin. More important, they are at risk for developing a type of aggressive kidney cancer at a young age. The syndrome is due to a mutation in a gene called fumarate hydratase.

Patients with the suspected syndrome should undergo genetic testing with a genetic counselor to confirm the diagnosis. A multidisciplinary team approach, including gynecologists, dermatologists, urologists, pathologists, and genetic counselors, is required for optimal patient management.

Though our patient did not have cancer, the fact that the pathologist was able to identify that she was at high risk of developing a serious malignancy in the future meant that she and her medical team could be on the alert. Working with a genetic counselor would also help any of her family members who shared the mutation to get an early warning of potential risk.

Walter Klein, M.D. is a board certified pathologist at Bryn Mawr Hospital and an active member of the Montgomery County Medical Society and the Pennsylvania Medical Society.