Association of hospital procedure volume and outcomes in patients with colon cancer at high risk for recurrence.
BACKGROUND
Studies that use registry data have demonstrated superior long-term overall survival after curative surgical resection of colon cancer at hospitals where the volume of such surgeries is high. However, because such administrative data lack information on cancer recurrence, the true nature of this relation remains uncertain.


OBJECTIVE
To determine whether hospital procedure volume predicts long-term outcomes of colon cancer surgery.


METHODS
Nested cohort study within a randomized clinical trial.


METHODS
Intergroup 0089 national adjuvant colon cancer study conducted between 1988 and 1992.


METHODS
3161 patients with high-risk stage II and stage III colon cancer.


METHODS
Overall survival and recurrence-free survival, by hospital procedure volume as defined by Medicare claims data.


RESULTS
With a median follow-up of 9.4 years, 5-year overall survival significantly differed across tertiles of hospital procedure volume (63.8% for patients who had resection at low-volume hospitals compared with 67.3% at high-volume hospitals; P = 0.04). After adjustment for other predictors of colon cancer outcome, the hazard ratio for overall mortality in patients treated at low-volume centers was 1.16 (95% CI, 1.03 to 1.32). However, the risk for cancer recurrence was not associated with hospital procedure volume. Five-year recurrence-free survival was 63.9% for patients who had resection at low-volume hospitals compared with 63.0% at high-volume hospitals (adjusted hazard ratio, 1.03 [CI, 0.89 to 1.18]). These findings did not materially change after stratification by other potential demographic and clinical predictors of outcome.


CONCLUSIONS
According to prospectively recorded data from a large clinical trial, patients whose colon cancer was resected at low-volume hospitals experienced a higher risk for long-term mortality; however, this increased mortality was not attributable to differences in colon cancer recurrences.
Dana-Farber Cancer Institute, Eastern Cooperative Oncology Group Statistical Center, and Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
Jeffrey A
JA
Meyerhardt
Paul J
PJ
Catalano
Deborah
D
Schrag
John Z
JZ
Ayanian
Daniel G
DG
Haller
Robert J
RJ
Mayer
John S
JS
Macdonald
Al B
AB
Benson
Charles S
CS
Fuchs
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D013505:Digestive System Surgical Procedures / Q000706:statistics & numerical data*; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D014481:United States / Q000453:epidemiology