DIAGNOSIS OF COLON-CANCER BY LAVAGE CYTOLOGY WITH AN ORALLY-ADMINISTERED BALANCED ELECTROLYTE SOLUTION

Objective: We wished to evaluate the feasibility of colon lavage cytol ogy using an orally administered balanced electrolyte solution. Method s: Thirty-three patients undergoing colonoscopy for suspected colorect al cancer were entered into the study. Fifteen of these patients event ually had pathological confirmation of colorectal cancer, and one pati ent had prostatic adenocarcinoma with invasion of the rectum. The othe r 17 patients had no colonoscopic evidence of neoplasm and therefore s erved as controls. Prior to colonoscopy, patients received 10 mg of bi sacodyl by mouth and enough Colyte to produce a clear anal effluent fo r cytological examination. The colon lavage cytology was interpreted b y a cytopathologist blinded to the clinical features of each case. Res ults: In 14 of 15 (93%) cases of biopsy proven colorectal cancer, the lavage cytology was positive: 10 cases demonstrated adenocarcinoma cel ls and four cases showed dysplastic cells. In contrast, the cytology w as negative for dysplastic or malignant cells in the control patients. Conclusions: Colon lavage cytology using an orally administered balan ced electrolyte solution provides acceptable specimens for cytological evaluation and had a 93% sensitivity and 100% specificity in our popu lation.