Intraoperative electron beam radiation therapy for locally recurrent rectal carcinoma

Treatment results for locally recurrent rectal cancers are poor. This is a result of the fact that surgery is hampered due to the severance of the anatomical planes during the primary procedure and that radiotherapy is limited by normal tissue tolerance, especially after previous irradiation. This paper describes the results of a combined treatment modality in this patient group.

From 1994 to 1998, 37 patients with locally recurrent rectal cancer, but without distant metastatic disease, received a combined treatment consisting of 50.4 Gy preoperative irradiation or, in case of previous radiotherapy, 30 Gy reirradiation or no irradiation, followed by radical surgery and intraoperative electron beam radiotherapy boost.

Fifteen patients received a radical resection (R0), eight a microscopic irradical resection (R1), and 14 a macroscopic irradical resection (R2). The overall 3-year local control (LC), disease-free survival (DFS), and overall survival rates were 60%, 32%, and 58% respectively. Radicality of resection (R0/R1 vs. R2) turned out to be the significant factor for improved survival (p < 0.05), DFS (p = 0.0008), and LC (p = 0.01). Preoperative (re-)irradiation is the other significant factor in survival (p = 0.005) and DFS (p = 0.001) and was almost significant for LC (p = 0.08). After external beam radiation therapy (EBRT) a significantly higher resection rate was obtained (R0/R1 vs. R2 p = 0.001). Symptomatic peripheral local recurrences have a significantly worse prognosis and higher rate of R2-resection (p = 0.0005).

Centralization of locally recurrent rectal cancer patients enabled the development of an aggressive multimodality treatment, which in turn led to promising results. Distant failure is still a drawback.