Medically reviewed by Dr. C.H. Weaver M.D. Medical Editor updated 4/2019
Patients diagnosed with Stage I uterine cancer have cancer that has not spread outside the uterus. Stage IA is cancer confined to the inner layer of cells of the uterus (endometrium). Stage IB is cancer that invades less than one half of the muscle wall of the uterus. Stage IC is cancer that invades more than one half of the muscle wall of the uterus.
Stage II uterine cancer involves the main body of the uterus and the cervix. Stage IIA cancer involves the uterus and only the surface lining of the cervix. Stage IIB cancer involves the uterus and extends into deep layers of the cervix.
Stage I and II uterine cancers are curable with surgery alone for the majority of patients. Optimal treatment may require additional therapeutic approaches in selected situations. Thus, it is important for patients to be treated at a medical center that can offer multi-modality treatment from gynecologic oncologists and radiation oncologists.
The standard treatment for stage I - II uterine cancer is a total abdominal hysterectomy (removal of the uterus) and bilateral salpingo-oophorectomy (removal of the fallopian tubes and ovaries) with or without removal of the pelvic and para-aortic lymph nodes. Despite complete surgical resection of all cancer, 5-20% of patients will experience recurrence of their cancer. This is because some patients with stage I cancer have microscopic cancer cells that have spread outside the uterus and therefore were not removed by surgery. These cells can cause relapses that follow treatment with surgery alone, therefore some patients may benefit from additional adjuvant treatment (adjuvant therapy) to decrease the risk of cancer recurrence. There is a progressive increase in local and distant cancer recurrences in patients with Stage IA, IB and IC disease and in patients with well, moderately and poorly differentiated cancers following treatment with surgery alone. To learn more about surgery, go to Surgery for Uterine Cancer.
Adjuvant therapy is the delivery of cancer treatment following local treatment with surgery and may include chemotherapy, radiation therapy and/or biologic therapy.
Radiation therapy is the most commonly used adjuvant therapy for early-stage uterine cancer. The decision about whether to use radiation therapy is often based on a woman’s risk of cancer recurrence. Women at low risk of recurrence may be treated with surgery alone, while women at higher risk of recurrence may be treated with surgery followed by radiation therapy. Risk of recurrence is influenced by characteristics such as the extent of the cancer and the grade of the cancer. The grade of the cancer refers to how abnormal the cancer cells appear; higher-grade cancers have a higher risk of recurrence.
Women who are candidates for adjuvant radiation therapy may be treated with external beam radiation therapy to the pelvis and/or vaginal brachytherapy.(1-3)
Adjuvant External Beam Radiation Therapy: External beam radiation therapy (EBRT) is given via machines called linear accelerators, which produce high-energy external radiation beams that penetrate the tissues and deliver the radiation dose deep into the areas where the cancer resides. Studies suggest that adjuvant radiation therapy to the pelvis reduces the risk of cancer recurrence but does not improve overall survival for most women with early-stage uterine cancer.(1)
Adjuvant Brachytherapy: Brachytherapy treatment involves the placement of a radioactive isotope into the vagina in order to treat the “vaginal cuff” region. The vaginal cuff is the part of the vagina that was closest to the uterus; it is a common site of uterine cancer recurrence.
Studies suggest that brachytherapy reduces the risk of cancer recurrence in the vagina with fewer side effects than external radiation therapy to the pelvis. Brachytherapy can, however, adversely affect sexual function. Furthermore, the effect on overall survival is likely to be small.(1)
Treatment of Stage II uterine cancer with surgery followed by adjuvant brachytherapy and external beam radiation therapy has been reported to cure 60-80% of patients.
The results of a clinical trial performed in 788 women with endometrial cancer at high-risk stage I or II or stage III or IV uterine cancer that did not extend beyond the abdominal cavity and had ≥2 cm residual tumor was reported in 2019 that evaluated 3 different chemotherapy treatment regimens was reported. Women were treated with either doxorubicin + plus cisplatin, Taxotere (docetaxel) + cisplatin, or paclitaxel + carboplatin and directly compared. No difference in overall survival or time to cancer progression was found suggesting all 3 regimens were feasible.
At 5 years the survival without cancer progression was 73.3% for doxorubicin + cisplatin, 79.0% for Taxotere + cisplatin, and 73.9% for paclitaxel + carboplatin; 5-year OS rates were 82.7%, 88.1%, and 86.1%, respectively.(4)
Strategies to Improve Treatment
The progress that has been made in the treatment of Stage I uterine cancer has resulted from the development of multi-modality treatments and doctor and patient participation in clinical trials. Future progress in the treatment of Stage I uterine cancer will result from continued participation in appropriate clinical trials. Currently, there are several areas of active exploration aimed at improving the treatment of uterine cancer.
Minimally invasive surgery: Traditionally, surgery for uterine cancer has been performed using a procedure known as a laparotomy. During a laparotomy, the surgeon makes a large incision in the abdomen in order to view and remove the uterus and other organs. A less invasive approach to surgery is laparoscopy, in which the surgeon makes only a few small incisions in the abdomen and views the inside of the abdomen using a small camera. Minimally invasive surgery may also be performed using robotics, in which a surgeon remotely operates a machine that holds the surgical instruments. Potential benefits of minimally invasive surgery include faster recovery time and less pain. Studies conducted thus far suggest that minimally invasive surgery is a safe and effective alternative to laparotomy for selected women with uterine cancer. Other studies are underway.(2)
Preservation of fertility: Up to 5% of uterine cancer diagnoses occur in women under the age of 40, many of whom have not yet had children.1 For some of these women, it may be possible to preserve the uterus and the ability to have children after cancer treatment by treating the cancer with a progestin (a hormonal therapy drug). This option is usually only considered for women with very early-stage and low-grade cancer.
- Lu KH. Management of early-stage endometrial cancer. Seminars in Oncology. 2009;36:137-144.
- Humphrey MM, Apte SM. The use of minimally invasive surgery for endometrial cancer. Cancer Control. 2009;16:30-37.
- Cannon GM, Geye H, Terakedis BE et al. Outcomes following surgery and adjuvant radiation in stage II endometrial adenocarcinoma. Gynecologic Oncology. 2009;113:176-180.
- JAMA Oncol. 2019 Mar 21. Epub ahead of print