The value of fibrosis score and 18F-FDG by positron emission tomography-computed tomography in lung cancer patients with interstitial lung disease.

Background: Compared to general population, patients with interstitial lung disease (ILD) shows an increased risk of lung cancer (LC), and higher LC complications. Hence, this study aims to analyze the factors related to the postoperative complications and mortality of patients with malignant lung tumor-and ILD after surgical resection.

Methods: This study analyzed the clinical information, surgical conditions, preoperative computed tomography (CT) and positron emission tomography (PET) examination data, as well as postoperative follow-up data of 60 non-small cell LC patients and 60 non-small cell LC patients with interstitial lung disease (LC-ILD). In this study, 120 patients with non-small cell LC were retrospectively reviewed, of which 60 were assigned to LC group and 60 to LC-ILD group. Cohorts were evaluated for differences in clinical data, surgical conditions, preoperative CT/PET examination data, and postoperative follow-up data.

Results: The postoperative complications in the LC-ILD group were slightly higher than those in the LC group (P<0.001), and the prognosis of LC patients with ILD was significantly worse than that of those without ILD (P=0.048). The standardized uptake value ratio (SUVR) of noncancerous interstitial pneumonia (IP) area in patients with postoperative complications was higher than that of patients without complications (P=0.005), and it was the risk factor for postoperative complications in LC-ILD group [hazard ratio (HR) 3.384 (1.023-25.441); P=0.02]. Until the end of follow-up, the CT scores of non-survivors were higher than those of survivors (9.30±3.56 vs. 5.52±2.26; P=0.001). Age [HR 3.919 (1.094-7.789); P=0.04], the CT score [HR 2.352 (1.028-4.033); P=0.007], and smoking history [HR 0.354 (0.096-0.643); P=0.03] were the risk factors for mortality.

Conclusions: The postoperative complications and mortality of LC-ILD significantly increase. Higher SUVR of noncancerous IP area usually indicates an increase of postoperative complications. Higher CT score and smoking history suggest a poor prognosis. A follow-up longitudinal study is needed to validate the findings.