Prevalence of and risk factors for presenting initial respiratory symptoms in patients undergoing surgery for lung cancer

Background: Patients with early stage lung cancer seldom present initial respiratory symptoms, causing a delayed diagnosis and missed opportunity to receive operation. This study aimed to investigate the prevalence of initial respiratory symptoms and identity what factors would predispose lung cancer patients to present initial respiratory symptoms in patients undergoing lung cancer surgery. Methods: A retrospective chart review was conducted on 3,203 patients undergoing surgery for primary lung cancer. The prevalence of initial respiratory symptoms was investigated and the comparisons of clinicopathological parameters were performed between patients with and without initial respiratory symptoms or between patients with single and multiple initial respiratory symptoms. Independent risk factors for presenting initial respiratory symptoms or multiple initial respiratory symptoms were identified using a logistic regression. Results: A total of 1,474 (46.0%) patients with lung cancer were admitted to hospital due to present initial respiratory symptoms. Symptom clusters of cough or sputum (33.1%) and bloody sputum or hemoptysis (16.7%) presented as the two major chief complaints for medical consultation while chest pain (6.9%) and chest distress or dyspnea (5.6%) remained relatively unusual. Multiple analyses found that coexisting chronic obstructive pulmonary disease (OR=1.70, 95% CI=1.41—2.05), tumor size >3 cm (OR=2.27, 95% CI=1.93—2.67), squamous cell carcinoma (OR=2.22, 95% CI=1.86—2.65), tumor located in left lower lung (OR=1.39, 95% CI=1.10—1.74) and advanced tumor stage (OR=1.27, 95% CI=1.06—1.52) were independent risk factors for presenting initial respiratory symptoms. Furthermore, current smoking (OR=1.36, 95% CI=1.07—1.73), tumor size >3 cm (OR=1.53, 95% CI=1.21—1.93) and squamous cell carcinoma (OR=1.68, 95% CI=1.32—2.15) were demonstrated to be independent risk factors for presenting multiple initial respiratory symptoms. Conclusions: Presenting initial respiratory symptoms was the common cause for medical consultation in patients undergoing lung cancer surgery. Patients with lung cancer in larger tumor size or squamous cell carcinoma more likely presented initial and even multiple initial respiratory symptoms.