EARLY COLORECTAL CANCER DETECTION IN SOUTH AFRICAN PUBLIC HOSPITALS USING A POINT-OF-CARE FECAL IMMUNOHISTOCHEMISTRY TEST shakeelkader2006@gmail.com

PW02-14

EARLY COLORECTAL CANCER DETECTION IN SOUTH AFRICAN PUBLIC HOSPITALS USING A POINT-OF-CARE FECAL IMMUNOHISTOCHEMISTRY TEST

2

South Africa

Oral or Poster

Colorectal cancer (CRC) is the third most diagnosed cancer worldwide, with increasing incidence in sub-Saharan Africa. In South Africa, late-stage diagnosis and limited endoscopic capacity hinder early detection efforts. This study evaluates whether a point-of-care fecal immunohistochemistry test (POC-FIT) can risk-stratify symptomatic patients and prioritize those at highest risk for CRC in resource constrained country without a current screening policy for CRC.

From September 23, 2022, adults (≥18 years) with ≥1 “red flag” lower gastrointestinal symptom (weight loss, altered bowel habits, rectal bleeding, iron deficiency anemia, abdominal mass) referred for colonoscopy at two public hospitals in Durban were enrolled in a prospective cohort. Demographic, clinical, POC-FIT, and colonoscopy findings were recorded. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of POC-FIT for invasive adenocarcinoma were calculated.

Of 326 patients, 293 were included in the interim analysis. Cecal intubation was achieved in 87.9%, with adequate bowel prep in 68.5%. Colonoscopy was normal in 71%; 19 (6.5%) had low-grade dysplasia, 5 (1.7%) high-grade dysplasia, and 24 (8.2%) invasive adenocarcinoma. Of 243 patients with valid POC-FIT, the positivity rate was 60%. POC-FIT sensitivity and specificity for invasive adenocarcinoma were 72% and 41%, respectively, with a PPV of 9% and NPV of 95%.

POC-FIT has high NPV but low PPV for CRC among symptomatic South African patients. Larger sample analysis will inform development of a clinical prediction model integrating FIT with demographic and clinical data in a country without a current screening program.