| Theme |
Current Status of Colorectal Cancer Screening |
| Title |
Sensitivity and Positivity Rates for Fecal Occult Blood Test in Colorectal Cancer Screening Program |
| Author |
Takenobu Shimada |
Cancer Detection Center of Miyagi Cancer Society |
| Author |
Katsuaki Kato |
Cancer Detection Center of Miyagi Cancer Society |
| Author |
Yoshifumi Inomata |
Cancer Detection Center of Miyagi Cancer Society |
| Author |
Daisuke Shibuya |
Cancer Detection Center of Miyagi Cancer Society |
| Author |
Shigeru Hisamichi |
Cancer Detection Center of Miyagi Cancer Society |
| [ Summary ] |
The evaluation of immunological fecal occult blood test (IFOBT) for colorectal cancer screening should be carried out by focusing on not only the accuracy of diagnostic examinations but also the effectiveness of the entire system. From this point of view, the sensitivity and positivity rates for IFOBT were examined. A single screening program with a two-day IFOBT showed low sensitivity levels, only 42 - 58 %. However, the majority of false-negative cases for single-year screening were diagnosed as early stage cancers with the subsequent screening programs. Therefore, when cancer cases which were detected with IFOBT within one or two years after the first screening were excluded from the false-negative cases, the sensitivity rates was estimated to be 74 - 84 %. This suggests the importance of consecutive annual screening. In expectation of an increase in cancer detection rates, the cut-off values for IFOBT may be lowered. However, this change may concurrently cause higher positivity rates. Since the positive predictive value was low at around the cut-off value, it should be considerable that the lower cut-off values may limit the efficacy of the entire screening system. |