Chest pain is a common symptom with a complex etiology involving multiple organs and systems. Cardiovascular, digestive and respiratory diseases can cause chest pain. A single condition usually reformulates and can cause this symptom, but a combination of conditions can also cause it. This case reports a 69-year-old male suffered from recurrent chest pain. Coronary heart disease, gastroesophageal reflux disease and left lung adenocarcinoma were diagnosed successively for nearly 1 year. The patients focus on one disease, and the medical staff neglects to deal with multiple diseases simultaneously. Ambiguous evidence and patients' unmotivated attitudes towards treatment make early diagnosis of lung cancer difficult. Treatment for coronary heart disease and gastroesophageal reflux disease masks the symptoms of lung cancer to some extent, resulting in a skewed diagnostic focus. This report highlights the need for clinicians to improve communication with patients to enhance treatment adherence and provide comprehensive screening, identification, and treatment of chest pain etiologies to prevent delays in patient treatment. The findings also suggest that awareness of the therapeutic and prognostic impact of interstitial lung disease on lung cancer should be improved, which is essential for the development of clinical treatment protocols.© 2025. The Author(s).