Surveillance for second primary colorectal cancer after adjuvant chemotherapy: an analysis of Intergroup 0089.
BACKGROUND
The incidence of second primary colorectal cancer in patients with a history of colon cancer, compared with patients with a history of adenomatous polyps, is unknown. It is unclear whether guidelines for colonoscopy screening in patients with polyps are appropriate for patients with previous colon cancer.


OBJECTIVE
To determine the incidence of second primary colorectal cancer after treatment for localized colon cancer and to compare this incidence with that of first primary colorectal cancer in both the general population and high-risk patients.


METHODS
Historical cohort study.


METHODS
An international, multi-institutional trial of adjuvant 5-fluorouracil-based chemotherapy for localized colon cancer.


METHODS
3278 patients with resected stage II and stage III colon cancer.


METHODS
Occurrence of endoscopic or radiologic colon surveillance and incidence of second primary colorectal cancer.


RESULTS
Forty-two cases of second primary invasive colon cancer were found over 15 345 person-years of follow-up, yielding an incidence rate of 274 per 100 000 person-years (95% CI, 196 to 369 per 100 000 person-years) and a cumulative incidence of 1.5% (CI, 1.1% to 2.0%) at 5 years. This rate was compared with rates of first colon cancer in two reference groups: the general population and patients who had undergone frequent colonoscopy and polypectomy because of a history of adenomatous polyps; standardized incidence ratios were 1.6 (CI, 1.2 to 2.2) and 6.8 (CI, 2.7 to 22.0), respectively.


CONCLUSIONS
The incidence of second primary colorectal cancer remains high despite intensive surveillance strategies.
Green
Robert J
RJ
The Helen and Harry Gray Cancer Institute, 1309 North Flagler Drive, West Palm Beach, FL 33401, USA.
Metlay
Joshua P
JP
Propert
Kathleen
K
Catalano
Paul J
PJ
Macdonald
John S
JS
Mayer
Robert J
RJ
Haller
Daniel G
DG
D000236:Adenoma / Q000473:pathology / Q000601:surgery; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D003111:Colonic Polyps / Q000473:pathology / Q000601:surgery; D003113:Colonoscopy; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D006801:Humans; D015994:Incidence; D008297:Male; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors
D000964:Antimetabolites, Antineoplastic; D005472:Fluorouracil