F-Hb concentration at FIT may help define screening interval

Top line:

patient’s feces hemoglobin concentration (f-Hb) on a fecal immunochemical test (FIT) may help determine optimal screening intervals such as: colorectal cancer (CRC).

methodology:

• In an ongoing study, researchers analyzed the dose-response relationship between f-Hb concentrations and the presence of advanced neoplasms (i.e., advanced adenomas or CRC). colonoscopy Screening in Germany.

• The analysis evaluated data from 7,398 men and women aged 50 to 80 years, after excluding younger and older patients and patients with colorectal cancer or a history of colorectal cancer. inflammatory bowel diseaseand those with other factors for colonoscopy.

• Participants underwent quantitative FIT (FOB Gold; Sentinel Diagnostics) before screening colonoscopy and f-Hb concentrations (μg/g feces): <1.7 (SENTiFIT detection limit, 270), from 1.7 <8, 8 to < 9, 9 to < 10, 10 to < 12, 12 to < 17, 17 to < 25 (positive FIT threshold), 25 to < 45, and ≥ 45.

• Subgroup analyzes were performed within f-Hb categories by gender and age.

• Adenomas larger than 1 cm, adenomas with a (tubulo)villous component, and high-grade dysplasia were considered advanced.

remove:

• Overall, 41% of participants had f-Hb concentrations less than 1.7 μg/g in feces, and 81% had f-Hb concentrations less than 8 μg/g. 10% had a positive test result with an f-Hb concentration of 17 µg/g or higher.

• The prevalence of advanced neoplasms increased from 6% in people with f-Hb concentrations <1.7 μg/g to 22% in the group with the highest FIT-negative results, and in the group with the highest FIT-positive results (≥17 μg/g). ) group increased up to 51%. /g).

• The overall diagnostic accuracy was 9.9% positive rate, 39% sensitivity and positive predictive value, and 93% specificity and negative predictive value at a cutoff of 17 µg/g.

in fact:

The study results “indicate that people at the upper end of negative FIT values ​​have a higher risk of colorectal cancer than those at the lower end,” the authors wrote. “Although it adds complexity, this suggests benefits from personalizing screening intervals.”

sauce:

The study was led by Dr. Tobias Niedermayer from the German Cancer Research Center in Heidelberg. Published online on November 7th Annals of Internal Medicine.

Limitations:

Limitations include limited generalizability to other FIT brands and other populations, statistical power, and cross-sectional design.

Disclosure:

This study was funded by grants from the German Research Council, the Federal Ministry of Education and Research, and German Cancer Aid. The authors reported no disclosures of interest.