Analysis of solitary pulmonary nodule after surgical resection in patients with 18F-FDG positron emission tomography integrated computed tomography in the preoperative work-up

Abstract

Introduction: To analyse clinicopathological characteristics of patients operated for pulmonary solitary nodule (PSN) and 18F-FDG integrated PET-CT scan after surgical resection.

Methodology: Retrospective study on a prospective database of patients operated from January 2007 to October 2017 for PSN without preoperative diagnosis. Dependent variable was anatomopathological result (benign vs malignant) of PSN. Variables of the study were: age, sex, PET-CT uptake, SUVmax, smoking history, COPD, previous history of malignant disease, tumoral location, and tumour size on CT-scan.

Results: A total of 305 patients were included in this study, 225 (73.8%) men, 80 (26.2%) women, mean age = 63.9 (range 29-86 years), mean size PSN = 1.68 (s.d. .65 cm), benign = 46 (15.1%), malignant = 258 (84.6%), type of resection: pulmonary wedge = 151 (49.5%), lobectomy = 141 (46.2%), segmentectomy = 12 (3.9%), exploratory intervention = 1 (0.3%). Postoperative mortality was 1.9%. COPD = 50.8% cases, previous cancer disease = 172 cases (56.4%), smoking history = 250 cases (82.0%), positive PET = 280 cases (91.8%), PSN in upper pulmonary fields = 204 cases (66.9%), median SUVmax = 3.4 (range 0-20.7). Backward stepwise binary logistic regression model showed that age, SUVmax, previous malignant disease and female sex were independent risk factors with statistical significance (p < .05). Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 94.6%, 23.4%, 87.1%, 44.0%, and 83.6% respectively. There were 14 false negative cases (4.6%) and 36 false positive cases (11.8%).

Conclusions: Age, SUVmax, previous malignant disease, and female sex were independent risk factors in our study. Each case should be individually evaluated in a multidisciplinary committee, and the patient's preferences or concerns should be kept in mind in decision-making. Surgical resection of PSN is not exempt from morbidity and mortality, even in sublobar or pulmonary wedge resection.

Keywords: Cirugía; Cáncer de pulmón; Lung cancer; Nódulo pulmonar solitario; PET-TC; PET-TC scan; Solitary pulmonary nodule; Surgery.