Radiotherapy (radiotherapy, radiatio) is used postoperatively in a risk-adapted manner = adjuvant radiotherapy). The following procedures are available for this purpose:
- Vaginal brachytherapy ((local, intravaginal irradiation) in the afterloading procedure (typical dose concept 3 times 5-7 Gy).
- External radiotherapy as teletherapy (percutaneous irradiation) with high-energy photons at the linear accelerator.
- Intensity-modulated radiotherapy.
Primary radiotherapy is indicated in patients,who can not be operated because of other disease risks. Note: X-ray sensitivity of tumor cells, that is, the effectiveness of radiotherapy on cancer cells, in endometrial cancer is strongly influenced by the gene ERCC6L2. A mutation of this gene that prevents cancer cells from repairing double-strand breaks in their DNA causes this. Patients with this mutation had 100% survival after radiotherapy. Of the patients whose ERCC6L2 was not disrupted, only half had died after 10 years.CONCLUSION: This finding suggests that ERCC6L2 is a predictive biomarker of radiotherapy response.
Stage-dependent radiotherapy [S3 line]
Postoperative external beam radiotherapy of the pelvis, endometrial carcinoma type I, stage I-II.
| Stage | Recommendations |
| pT1a, pNX/0, G1 or G2, endometrioid EC (type I), after hysterectomy with or without lymph node dissection | Neither brachytherapy nor percutaneous irradiation |
Postoperative vaginal brachytherapy for endometrial carcinoma type I, stage I-II.
| Stage | Recommendations |
| pT1a, pNX/0 without involvement of myometrium, G3, endometrioid EC (type I). | Vaginal brachytherapy may be performed to reduce the risk of vaginal recurrence |
| pT1b, G1 or G2 pNX/0 and stage pT1a (with myometrial involvement), G3 pNX/0, endometrioid EC (type I) | Vaginal brachytherapy (to reduce the risk of vaginal recurrence). |
| pT1b pNX G3 or stage pT2 pNX, endometrioid EC (type I). | Vaginal brachytherapy should be performed; alternatively, percutaneous radiotherapy may be performed |
| After systematic LNE at stage pT1b pN0 G3 or at stage pT2 pN0, endometrioid EC (type I). | vaginal brachytherapy |
| pT1pNX (any grading) with “substantial VSI” (highest stage in three-tiered graduation of lymphatic vessel invasion) | Percutaneous pelvic irradiation instead of vaginal brachytherapy |
Postoperative radiotherapy for endometrial carcinoma type I, stage III-IVA.
| Stage | Recommendations |
| Positive LK, involvement of the uterine serosa, adnexa, vagina, bladder, or rectum (i.e., stages III to IVA overall) with endometrioid EC (type I) | Postoperative external pelvic irradiation in addition to chemotherapy to improve local control |
Postoperative radiotherapy for endometrial carcinoma type II.
- The indication for postoperative vaginal brachytherapy or external pelvic irradiation for type II carcinoma (serous or clear cell) should be based on the recommendations for type I (endometrioid) carcinoma of grade G3 of the same stage.
Further notes
- Adjuvant radiation therapy is not indicated for low local recurrence risk (recurrence of disease at the same site): stage T1a (FIGO I A), endometrioid carcinoma, G1/G2.
- In advanced endometrioid carcinoma (stage III/IV), local radiotherapy as radiochemotherapy (combination of radiotherapy and chemotherapy) may reduce the number of local recurrences compared with chemotherapy alone, but the number of distant metastases was surprisingly higher (27 versus 21%), so no advantage in progression-free survival was apparent after local radiotherapy.
- Adjuvant radiochemotherapy (RCT; adjuvant: after surgery) versus adjuvant external pelvic radiation (RT) alone, at a median follow-up of 60.2 months, showed that the rates of 5-year recurrence-free survival differed significantly: 75.5% (concurrent RCT) versus 68.6% (RT alone; HR 0.71; 95% confidence interval [95% CI] 0.53-0.95, p = 0.022); however, the rate for 5-year overall survival did not differ: in the RCT group, this was 81.8% and in the RT alone group, this was 76.7% (HR 0.76; 95% CI 0.54-1.06; p = 0.11). Note: In both study arms, 30% of patients had stage I tumors, 24% (RCT) or 27% (RT) had stage II tumors, and 46% (RCT) or 43% (RT) had FIGO stage III tumors.CONCLUSION: Chemotherapy should be weighed on an individual basis, with special consideration given to higher therapy-related toxicity and tumor stage.
- Adjuvant external pelvic radiotherapy frequently causes incontinence (urinary or fecal incontinence). Adjuvant vaginal brachytherapy is much less likely to cause side effects. External pelvic radiotherapy should now only be used in patients at high risk of recurrence.
- In stages T1 and T2 (FIGO I and FIGO II), radiotherapy significantly reduced the local recurrence rate (tumor recurrence at the same site) with no effect on overall survival. The figures are not meaningful for advanced stages.
- For pelvic wall recurrences, radiotherapy achieves a 5-year survival rate of about 70-80%.
- Palliative radiotherapy (treatment that does not aim to cure a disease but to relieve symptoms or reduce other adverse consequences): As a palliative measure for vaginal bleeding or pain from vaginal stump or pelvic wall recurrence, low total dose radiotherapy can be used even after previous radiotherapy [S3 guideline]….
