Treatment Of Uterine Cancer
Like with the treatment of cancer of the cervix, the treatment has to be planned carefully taking into consideration the exact location of the cancer at the time of diagnosis. The ynecologist/oncologist will include information about the histology, the grade of the tumor and the cancer stage before the ideal treatment modality and/or combination can be recommended for the patient. A large body of literature exists from many clinical trials where treatments have been refined and survivals are now about 15 to 20% better for most stages compared to the early 1980's.
Five-year survivals for Uterine Cancer
One such study involved a group of patients with uterine cancer who were separated into grades and surgical treatment was given in combination with or without radiation.
The following 5-year survivals were obtained (data averaged from Ref. 1, p. 1198 and 1200, arranged as a table here).
| Vaginal recurrence rate (different grades of uterine cancer) |
| Grade: |
With radiation: |
Without radiation: |
| 1 |
4% |
4% |
| 2 |
3% |
9% |
| 3 |
9% |
24% |
It is clear from this that there was a 15% survival advantage for grade 3 tumors with radiation therapy of the pelvic lymph nodes. This way the high number of invisible lymph gland metastases in grade 3 tumors were neutralized.
Similarly, there have been studies regarding recurrence rates after hysterectomy for grade 1 patients where only surgery was chosen as the sole therapy. In one such study patients were followed who developed isolated high vaginal recurrences. They were treated with a combination of external beam radiation combined with brachytherapy (see below) and then followed for 5-year survival studies. The tumor size at the time of the recurrence determined the longterm survival: It can be seen from the table, there was a much better survival with the smaller lesions than with larger lesions, when they both were treated with radiotherapy.These type of observations and others are what oncologists incorporated into the present day treatment against uterine cancer.
| 5-year survival for isolated high vaginal recurrence (uterine cancer) |
| size of lesion (diameter): |
% survival: |
| 2 cm or less |
74% |
| more than 2 cm |
30% |
Treatment against uterine cancer has become complex as so many variables have entered into the equation. Early cancer like stage IA and IB are often treated with surgery only, although some authorities err on the cautious side and cover with some form of radiotherapy.
As the table below shows, stage IC and stage II do best with a combination of surgery and radiotherapy. Stage III and IV are usually treated with radiotherapy alone because surgery or combination surgery and radiotherapy did not yield better survivals. There is a subgroup of patients with stage IV disease who will benefit from a radical surgical procedure called " pelvic exenteration". They have to be in fairly stable condition for this surgical procedure, in which all of the visible cancerous tissue is removed in an extensive debulking procedure. Subsequent to that radiotherapy and chemotherapy to prevent recurrence is given. 5- year cure rates of 40% to 50% have been achieved this way!
| 5-year survival for uterine cancer |
| Stage (FIGO): |
% survival: |
Comments: |
| IA, IB |
90% |
low risk:surgery |
| IC |
80% |
higher risk:surgery+radio-Rx |
| II |
75% |
Surgery + radiotherapy |
| III |
46% |
extended field radio-Rx for paraaortic lymph nodes |
| IV |
5%(or 40%*) |
| * With radical surgery ( called "pelvic exenteration"), followed by radiotherapy and chemotherapy, 5-year survivals of 40% to 50% have been reported, but not every patient is a suitable candidate for this very extensive surgery. |
Surgery: Surgery consists usually of an abdominal hysterectomy and removal of both fallopian tubes and ovaries (called"bilateral salpingo-oophorectomy"). The oncological gynecologist also removes samples of pelvic and paraaortic lymph glands. All of the material is sent to the pathologist who will report back, which of he tissues contained cancer cells. This data is needed to decide whether radiotherapy is needed.
Radiotherapy is delivered in two ways. External beam therapy delivers radiation through the skin in overlapping beams that are mostly concentrating in the uterus, pelvic and paraaortic lymph gland areas.
Using spatial computer models radiation doses can be accurately delivered in differently shaped pelvic cavities. and can be modifed according to body size and shape. This is supplemented by a direct dose of radiation from local "brachytherapy". With this form of radiotherapy a device, which has an "arm" (the name "brachy" means arm) that fits into the uterus and another piece that fits into the upper vagina, is placed for several hours until a certain dose has been delivered to the tissues.
Between these two delivery methods the radiation specialist can deliver curative doses of radiation with a minimum of side effects. The older technique with radioactive radium has largely been replaced in the 1980's with radioactive caesium (137-Cs), which has less side-effects than radium and is easier to apply. About 2% of patients experience major side effects such as bladder, rectum or gastrointestinal scarring. This, however is considered a very acceptable risk given the alternatives of not treating the cancer.
Chemotherapy:
It appears that uterine cancer is not very sensitive to chemotherapeutic intervention. However, multidrug combination therapy when combined with radiotherapy and surgery has made some difference in survival data as mentioned above. There are still tremendous immunosupressant side-effects that need to be overcome. Some future approaches might include monoclonal antibodies directed against tumor markers (Ref. 2).
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