Fig. 3.

Algorithm 2: Investigation pathway for a patient with a de novo raised carcinoembryonic antigen (CEA). ^aOrgan-specific investigations: tumor markers, CT scan, colonoscopy, gastroscopy, mammography, cystoscopy, US, bone scan, biopsy, other test as required. Clinical review includes: a full history and examination of the thyroid, breast, thorax, abdomen and pelvis, visual field testing, fundoscopy, long bones examination. Look for melanoma. In females, cervical examination. In males, a prostate examination. PET/CT, positron emission tomography-computed tomography.