[Randomized controlled trial of sequence mass screening program for colorectal cancer].
OBJECTIVE
In order to assess the effectiveness of mass screening program for colorectal cancer, a sequence mass screening program based on RPHA-FOBT and individual quantitative risk assessment model (attributive degree value, AD) was used and evaluated on its effectiveness in a randomized controlled trial.


METHODS
The residents of Jiashan county aged 30 years and over were randomized to either screening or control groups in 1989. Participants in screening group were asked to fill in a questionnaire and to submit one paper slide with stool. Participants who tested positive underwent diagnostic evaluations including flexible sigmoidoscopy and colonoscopy.


RESULTS
According to the cancer registry of Jiashan, after initial mass screening in 1989, the 8-year cumulative incidence per 1,000 of colorectal cancer in screening and control groups appeared to be 3.95 (95% CI 3.81 - 4.10) and 4.01 (95% CI 3.86 - 4.16) respectively. There was no significant statistical difference between two groups (P > 0.05). Nevertheless, the 8-year cumulative mortality for colorectal cancer in screening group (2.08 per 1,000; 95% CI 1.96 - 2.18) was reduced 14.7% comparing with the control group (2.44 per 1,000; 95% CI 2.33 - 2.55). In particular, the cumulative mortality of rectal cancer was significantly (31.7%) lower than that in control group. Log-rank test showed that survival rate of rectal cancer in screening group was higher than that in controls (log-rank = 9.01, P = 0.0027).


CONCLUSIONS
The sequential mass-screening program which based on RPHA-FOBT and ADV might reduce the mortality for colorectal cancer in the Chinese population.
Liu
X
X
Cancer Institute of Zhejiang University, Hangzhou 310009, China.
Zheng
S
S
Chen
K
K
Ma
X
X
Zhou
L
L
Yu
H
H
Yao
K
K
Chen
K
K
Cai
S
S
Zhang
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009780:Occult Blood; D012680:Sensitivity and Specificity; D012812:Sigmoidoscopy; D016019:Survival Analysis