Adjuvant continuous infusion 5-FU, whole-abdominal radiation, and tumor bed boost in high-risk stage III colon carcinoma: a Southwest Oncology Group Pilot study.
OBJECTIVE
Results of a combined modality adjuvant pilot program of low-dose continuous-infusion 5-fluorouracil, whole-abdominal radiation, and tumor bed boost in patients with colon cancer with involved nodes and serosal involvement are presented.


METHODS
Forty-one eligible patients with completely resected T3N1-2M0 colon cancer (modified Astler-Coller C2) were treated with 5-fluorouracil (5-FU) at a dose of 200 mg/m2/day by continuous infusion and 30 Gy of concomitant whole-abdominal radiation in 1 Gy fractions. An additional 16 Gy boost to the tumor bed was administered in 1.6 Gy fractions. After completion of combined modality treatment and a 21-day rest period, patients received 4 days of 5-FU at a dose of 1000 mg/m2 by continuous infusion every 28 days for nine cycles.


RESULTS
Five-year disease-free and overall survival estimates were 58 and 67%, respectively, for all T3N1-2 patients. Five-year disease-free and overall survival estimates for the 19 patients with four or fewer nodes were both 61%. Five-year disease-free survival and overall survival estimates for the 20 patients with more than four involved nodes were 55% and 74%, respectively (the exact number of involved nodes were unknown for two patients). Disease-free and overall survival estimates for patients treated with 5-FU and radiation compare favorably to the 5-FU plus levamisole arm of the intergroup adjuvant colon study (Int 0035/SWOG 8591) in patients with more than four positive nodes where the 5-year disease-free and overall survival estimates were 35% and 39%, respectively. Disease-free and overall survival estimates for patients with four or fewer nodes in the 5-FU plus levamisole arm of the intergroup study were 64 and 68%, which is not markedly different from results obtained with radiation and 5-FU in the current study. There were no treatment-related fatalities. Seventeen percent of patients had severe and 7% had life-threatening toxicity of any kind. One patient had an acute partial bowel obstruction and two patients had chronic low grade enteritis.


CONCLUSIONS
Continuous infusion 5-FU and whole-abdominal radiation with tumor bed boost should be further investigated in a larger trial of T3N1-2 colon cancer.
Fabian
C
C
University of Kansas Medical Center, Kansas City, USA.
Giri
S
S
Estes
N
N
Tangen
C M
CM
Poplin
E
E
Vogel
S
S
Goodwin
W
W
Rivkin
S
S
Fleming
T R
TR
Macdonald
J S
JS
D000328:Adult; D000368:Aged; D017024:Chemotherapy, Adjuvant / Q000009:adverse effects; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage* / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D010865:Pilot Projects
D005472:Fluorouracil