Decreasing Prevalence of Benign Etiology in Resected Lung Nodules Suspicious for Lung Cancer over the Last Decade

This study investigated treatment strategy for suspicious lung cancer with postoperatively proven benign etiology. In this retrospective study, we collected patients who underwent pulmonary resection for radiologically suspected lung cancer from 2010 to 2019 at Department of Thoracic Surgery, Fudan University Shanghai Cancer Center (FUSCC). Radiological features, preoperative follow-up time, preoperative pathology and postoperative pathology of these patients were documented. We classified resected benign lesions based on paraffin section and compared the therapy management performed on indeterminate lung nodules of 2 time periods (2010-2014 vs 2015-2019). 17,188 patients were included in this cohort and 1,381 (8.03%) cases were postoperatively proved to be benign lesions. Resected benign lesions proportion significantly decreased by years, from 14.5-6.2%. The respective resected benign lesions proportions for pure GGO nodules, part solid nodules and solid nodules were 5.3%, 3.0% and 11.7%. The resected benign lesions rate for patients with longer preoperative follow-up time was much lower (p < 0.001). Among the benign lesions, 14.2% were benign tumors, 25.7% were granulomatous, 30.2% were pneumonia, 18.0% were fibrosis and 11.9% were other types. If we consider that resections for granulomatous and pneumonia radiologically featured as solid nodules exceeding 2 cm, benign tumor and inflammatory pseudotumor are therapeutic, the nontherapeutic pulmonary resection rate is 4.26%. For patients with GGO nodules, the median preoperative follow-up time increased with the time being and the resected benign rate in period 2 (2015-2019) was significantly lower than that in period 1 (2010-2014). Wedge resection was the most common surgery strategy especially for small nodules and no matter for small or large nodules, the frequency of sublobar resection in period 2 was higher than that in period 1. The resected benign lesions rate at our department was relatively low and decreasing over the last decade. Meanwhile, our follow-up and surgical strategy improved over time. For patients with GGO nodules, 4-6months preoperative follow-up is recommended to avoid surgical intervention for benign lesions. For solid nodules with inconclusive diagnosis, limited resection should be first considered to maintain the balance between reducing the risk of cancer progressing and minimizing the resection for benign lesions.