Rectal cancer
Radiation therapy is used particularly for rectal cancer (cancer of the rectum), usually in combination with chemotherapy (radiochemotherapy, RCTX). It is used either before (neoadjuvant) or after surgery. However, studies have shown an advantage when radiotherapy was used before surgery rather than after: Forgoing neoadjuvant radiotherapy in patients with stage II/III rectal cancer decreased the probability of survival.
Therapy for stage II or III rectal cancer should be given in the following standard treatment steps:
- Radiochemotherapy (RCT; eg, fluorouracil/oxaliplatin; irradiation with 50.5 Gy)-with the goal of reducing tumor mass before surgical removal of the tumor.
- Surgery
- Chemotherapy (3 cycles of fluorouracil, leucovorin and oxaliplatin) – with the aim of destroying any micrometastases in the body.
Anal carcinoma
For anal carcinoma (anal cancer), radiochemotherapy (RCTX) is considered the standard of care. The success of therapy often does not become apparent until weeks or months after completion of treatment. The decision to perform any “salvage” surgery should not be made until 26 weeks after the start of RCTX.
The standard of care is radiation to the tumor, inguinal lymph nodes, and pelvic lymph nodes (total dose of 50.4-59.4 Gy) and concurrent intravenous chemotherapy (5-fluorouracil on days 1-4 and days 29-32 and mitomycin C on days 1 and 29).
Liver Metastases
Local ablative procedure for liver metastases (daughter tumors in the liver):
- Selective Internal Radiation Therapy (SIRT), indication: disseminated liver metastases from colorectal carcinoma in patients for whom no other therapeutic option is considered, and then only within clinical trials.
