THE ROLE OF DIAGNOSTIC OESOPHAGO-GASTRODUODENOSCOPY (OGD) AND COLONOSCOPY IN CANCER OF UNKNOWN PRIMARY

Objective: To study the role of gastrointestinal procedures, namely oesophago-gastroduodenoscopy (OGD) and colonoscopy, in helping to establish a definitive primary tumour site in cancer of unknown primary. Study Design: Prospective observational study. Place and Duration of Study: Shaukat Khanum Memorial Cancer Hospital & Research Centre, Lahore Pakistan, from Jan 2018 to Jan 2019. Methodology: A total of 115 patients included in the study were those, who underwent OGD and a colonoscopy for the diagnosis of a cancer of unknown primary. Data collected included demographics, baseline clinical characteristics, definitive diagnosis, tissue diagnosis and immune-histochemical stains. Primary outcome was the attainment of a definitive diagnosis via OGD and/or colonoscopy. Results: A total of 115 patients underwent a diagnostic gastrointestinal procedure. Of these 70 (61%) were males. Mean age was 63 ± 12.6 years (range 22-88 years). Abdominal pain comprised the most common presenting complaint, found in 61 (53%). The most common tissue diagnosis of the metastatic sites was adenocarcinoma 81 (70.45%). Tumour markers including carcinoembryonic antigen, alpha-fetoprotein and carbohydrate antigen 19-9 were checked in 90 (78.2%), 46 (40%) and 69 (60%) patients respectively. No patient reached a definitive diagnosis by means of OGD and/or colonoscopy. Conclusion: OGD and colonoscopy when done collectively as diagnostic procedures to look for a primary tumour, have no value in the evaluation of patients with cancer of unknown primary.