Uterine fibroid biopsy

Uterine fibroids are growths that appear in the uterus. They form in the myometrium, the muscle located just beneath the endometrium. It is possible to have several fibroids, which can grow quite large, varying in size from 1 to 20 cm.

This disorder affects nearly half of all women by the time they are 50. Frequently detected by chance during a routine exam, most fibroids cause no particular symptoms.

Symptoms, when they do occur, may include:

• Bleeding between menstrual cycles (metrorrhagia)
• Heavy menstrual bleeding (menorrhagia)
• Pelvic pressure
• Frequent urination
• Intestinal symptoms, including constipation

Fibroids can also increase the risk of infertility and are a source of risk during pregnancy (miscarriage, early contractions).

Uterine fibroids are benign tumors with no malignant potential. Even though the word “tumor” can make us fear the worst – uterine cancer – fibroids are a benign condition. They are noncancerous and do not metastasize to other organs.

The main risk is their similarity to uterine sarcoma, an extremely rare type of cancer. Uterine sarcoma accounts for 1 to 3 percent of malignant gynecologic tumors and tends to grow rapidly. Uterine sarcoma must be treated surgically, in order to completely remove the tumor. In practice, surgery consists in the removal of the uterus, fallopian tubes and ovaries (total hysterectomy with bilateral salpingo-oophorectomy). The main consequence of surgery is that the patient will no longer be able to become pregnant. There are also general risks inherent to any surgery.

Treating a fibroid, on the other hand, may simply involve a uterine artery embolization procedure. This minimally invasive interventional radiology technique is performed on an outpatient basis under local anesthesia. It preserves the patient’s fertility and carries a very low risk of complications. 

It is therefore crucial to determine whether a patient has a fibroid or cancer before any treatment is given. Previously, the diagnosis was primarily based on a pelvic MRI. But images of fibroids are complex, and it can be difficult to distinguish between a fibroid and uterine sarcoma.

A recent study (SARCGYN) analyzed the efficacy of biopsy in the preoperative diagnosis of uterine sarcoma (1). The results are unequivocal: a biopsy is a safe and accurate test.

According to the study, the microscopic and array-CGH analyses offered diagnostic precision of 94 percent and 100 percent, respectively. Performed on 34 patients, the biopsy caused no complications.

The study recommends systematically performing a biopsy following a suspicious MRI in order to determine the appropriate treatment.

A biopsy is used to rule out sarcoma, allowing the patient to avoid an unnecessary hysterectomy and benefit instead from a less aggressive, more appropriate treatment.

A uterine fibroid biopsy is a medical exam performed under local anesthesia in which a sample of tissue is removed using a needle. It is a pain-free procedure, possibly resulting in temporary discomfort and light bleeding after the exam.

In practice, the biopsy consists in removing a sample of the inner lining of the uterus.  Great care must be taken to avoid contaminating the neighboring areas in the event of a malignancy.

The sample is then sent to the lab for anatomic pathology analysis. This analysis makes it possible to accurately determine the cells’ malignant potential and identify not only the presence of cancer, but also its type, aggressiveness and stage.