Refining Treatment for High-risk Early Stage Endometrial Cancer
Name of the Trial
Phase III Randomized Study of Pelvic Radiotherapy Versus Vaginal Cuff Brachytherapy, Paclitaxel, and Carboplatin in Patients with High-Risk Stage I or II Endometrial Carcinoma (GOG-0249). See the protocol summary.
Dr. D. Scott McMeekin and Dr. Marcus Randall, Gynecologic Oncology Group
Why This Trial Is Important
Endometrial carcinoma is cancer that starts in the tissue lining the uterus called the endometrium. Women with early stage endometrial cancer are usually treated with surgery to remove the uterus (hysterectomy) and the ovaries and fallopian tubes (bilateral salpingo-oophorectomy). Although these surgical procedures cure most women with early stage disease, as many as 25 percent will have their cancer recur. Previous research has identified several risk factors that are associated with a likelihood for recurrence, including grade II or III tumors, deep invasion of the uterine muscle, spread of the tumor outside the uterus, and evidence of cancer in the surrounding lymph nodes or blood vessels.
Currently, patients with high-risk early stage endometrial cancer are treated with adjuvant external-beam radiation therapy to the pelvis to help prevent recurrence. Although often effective, this type of radiotherapy carries the risk of potentially severe side effects that can substantially limit quality of life. Consequently, researchers are eager to find better ways to prevent or delay the return of cancer in these patients.
Most recurrences in women with high-risk early stage endometrial cancer occur either in the vaginal cuff (the upper part of the vagina that connected to the cervix before the uterus was removed) or at distant sites throughout the body. Some researchers have suggested, therefore, that post-surgical treatment may be made safer by targeting only the vaginal cuff with radiotherapy and more effective by adding chemotherapy to help prevent systemic disease.
In this clinical trial, women with high-risk early stage endometrial cancer will be randomly assigned following surgery to receive one of two types of adjuvant therapy: brachytherapy targeted to the vaginal cuff in combination with chemotherapy or standard pelvic external-beam radiotherapy. Brachytherapy involves implanting radioactive seeds in the area where cancer cells may be present or where recurrence is likely to happen.
"A variety of trials have shown the value of radiotherapy for women with high-risk early stage endometrial cancer, so this study is really building on our previous experiences and evaluating the possible benefits of adding chemotherapy to radiotherapy in this subset of patients," said Dr. McMeekin. "This large study should reveal whether there is a benefit from the addition of chemotherapy and clarify the best way to improve care for a substantial portion of women with early stage endometrial cancer," he added.