The researchers assessed the long-term results of reirradiation in patients with recurrent rectal carcinoma, and published their findings in the September issue of Cancer.
A total of 103 patients with recurrent adenocarcinoma of the rectum underwent reirradiation with concurrent 5-fluorouracil-based chemotherapy.
The initial radiation dose to the pelvis ranged from 3000 to 7400 centigrays (cGy), with a median dose of 5040 cGy.
The median time from initial treatment to recurrence was 19 months.
The reirradiation doses ranged from 1500 to 4920 cGy, with a median dose of 3480 cGy.
After the reirradiation, 34 patients also underwent surgical resection for residual disease. Of these, 14 patients underwent pelvic exenteration and 11 patients underwent abdominoperineal resection. A further 4 patients underwent transanal transabdominal proctosigmoidectomy, 2 patients underwent full thickness local excision, and 3 patients underwent a Hartmann resection.
Follow-up ranged from 3 to 84 months, with a median follow-up of 2 years.
The team found that median survival for the whole group was 26 months and the 5-year actuarial survival rate was 19%.
|19% of reirradiated patients were alive after 5 years.
The median interval and 5-year survival rate of patients undergoing surgical resection after reirradiation was 44 months and 22%, compared with 14 months and 15% for patients treated with reirradiation only.
Treatment was generally well tolerated.
Some 15 patients required a treatment break and early termination of treatment for Grade 3 and higher diarrhea, moist desquamation, or mucositis.
The authors observed late complications in 22 patients. These included persistent, severe diarrhea in 18 patients (with 10 patients requiring long-term parental support), small bowel obstruction in 15 patients, fistula formation in 4 patients, and coloanal stricture in 2 patients.
However, there was no difference in incidence of acute or long-term complications by the total radiation dose delivered.
Mohammed Mohiuddin, of the University of Kentucky Medical Center, Lexington, concluded on behalf of fellow authors, "In patients with recurrent rectal carcinoma, high doses of reirradiation can be delivered with acceptable risks, without prohibitive long-term side effects.
"Surgical salvage and long-term survival of patients are possible."