노인에서 코로나19 확진 후 식욕저하 및 체중감소를 주소로 내원한 폐암 1예

A Case of Lung Cancer with Persistent Anorexia and Weight Loss after COVID-19 Infection

Post-acute COVID-19 syndrome is characterized by complaints of malnutrition, reduced fat mass, and low-level inflammation that occur after infection with coronavirus disease 2019 (COVID-19), and continuous functional decline such as fatigue and loss of appetite can occur. A 77-year-old male patient visited the Department of Family Medicine of a national university hospital complaining of unintentional weight loss of more than 5% and anorexia for two months. After he was diagnosed with COVID-19 two months prior, the symptoms began, and he had been receiving treatment at a primary clinic for suspected post-acute COVID-19 syndrome. Physical examination revealed pain in multiple areas, including the right chest, shoulder, and lumbar region, and decreased respiratory sounds in the left upper lung region. In blood tests, mild elevations of alkaline phosphatase and gamma glutamyl peptidase and severe elevations of carcinoembryonic antigen and carbohydrate antigen 19-9 were observed. Chest radiographs showed a focal opacity in the upper left region. On chest computed tomography, a 3-cm mass was observed in the left upper lobe. Subsequent positron emission tomography and endobronchial ultrasonography using a guide sheath confirmed that it was nonsmall-cell lung cancer with multiple metastases. This case reports anorexia and weight loss after COVID-19 infection and confirmed advanced lung cancer that was misdiagnosed as post-acute COVID-19 syndrome.