Pulmonary artery enlargement on routine staging 18F-fluodeoxyglucose positron emission tomography/CT for lung and oesophageal cancer.

Abstract

Pulmonary hypertension (PH) is an underdiagnosed condition associated with poor survival and increased post-operative mortality in lung cancer. CT-based parameters of pulmonary artery enlargement are strong predictors of PH. We used these parameters to investigate pulmonary artery enlargement in lung and oesophageal cancer. Consecutive patients with lung cancer (n = 100) or oesophageal cancer (n = 100) undergoing staging 18F-fluodeoxyglucose PET/CT were retrospectively identified. The transverse diameter of the main pulmonary artery (mPA) and ascending aorta, and the pulmonary artery-to-ascending aorta (PA:A) ratio were obtained. Abnormal values were defined following the Framingham Heart Study cohort. Lung cancer patients had a significantly increased mPA diameter compared to the oesophageal cancer patients (males: 27.29 ± 0.39 vs. 25.88 ± 0.24 mm, females: 26.10 ± 0.28 vs. 24.45 ± 0.18 mm). Similarly, a significantly increased proportion of these patients had an abnormal mPA diameter (males: 35.1% vs 12.5%, females: 32.6% vs 10.7%). Lung cancer patients also had a significantly higher PA:A ratio (males: 0.83 ± 0.01 vs. 0.79 ± 0.008, females: 0.85 ± 0.01 vs. 0.79 ± 0.009), with a larger proportion having an abnormal PA:A ratio (males: 24.6% vs 11.1%, females: 27.9% vs 14.3%). Simple measurements of mPA diameter and PA:A ratio reveal that lung cancer patients exhibit increased rates of pulmonary artery enlargement compared to oesophageal cancer patients. This study demonstrates there is an increased prevalence of pulmonary enlargement in lung cancer, easily detected on routine staging scans, holding implications for further work-up and risk stratification.