Preoperative CT Features May Help Select Patients With Stage IA NSCLC for Sublobar Resection

Data regarding CT features in patients with non–small cell lung cancer (NSCLC) led investigators to conclude that patient selection for sublobar resection versus more extensive surgery may be possible after factors such as peritumoral interstitial thickening and pleural contact were found to independently predict pathologic lymphovascular invasion (pLVI) and recurrence-free survival (RFS).¹

On preoperative CT, pLVI only occurred in solid-dominant part solid nodules (PSNs) and solid nodules with a solid portion of more than 10 mm in patients with stage 1A NSCLC, according to data published in the American Journal of Roentgenology (AJR).

“In patients with stage IA non–small cell lung cancer, pathologic lymphovascular invasion was observed only in solid-dominant part solid nodules and solid nodules with solid portion diameter over 10 mm,” corresponding author, Mi Young Kim, MD, of the department of radiology at the University of Ulsan College of Medicine, Asan Medical Center, said in a press release.²

The study population totaled 904 patients who underwent either lobectomy (n = 574) or sublobar resection (n = 330) for stage 1A NSCLC. The median age of the population was 62 years, with an even distribution of men (n = 453) and women (n = 451). The study utilized 2 thoracic radiologists to evaluate the findings from preoperative chest CT.

Overall, pLVI was found in 10.2% of patients (n = 92), and was only present in solid-dominant PSNs and solid nodules with a solid portion diameter of more than 10 mm. Among this group of solid nodules, 1 of the independent predictors of pLVI was peritumoral interstitial thickening (odds ratio [OR], 13.22; P <.05), with an achieved sensitivity, specificity, and accuracy of 80.4%, 76.7%, and 77.4%, respectively. The other predictor was pleural contact (OR, 2.45; P <.05), with an achieved sensitivity, specificity, and accuracy of 35.9%, 82.5%, and 74.3%, respectively.

When either feature was present, the achieved sensitivity for pLVI was 90.2%, specificity was 64.3%, and accuracy was 68.9%. RFS was observed to be independently predicted by this group of solid nodules for patients who underwent sublobar resection (P < .05).

“pLVI occurred only in solid-dominant PSNs and solid nodules with a solid portion measuring over 10 mm on preoperative CT,” wrote the investigators. “Among such nodules, peritumoral interstitial thickening and pleural contact greater than one quarter of the circumference of the nodule’s solid portion were associated with increased risk of pLVI and were also independent prognostic factors for RFS after sublobar resection.”

For this research, the main limiting factor was that the retrospective study was conducted at 1 center. The research team recommends that a multicenter study should be undertaken to confirm the data.

The investigative team suggests that these features, including the focal nodules, peritumoral interstitial thickening, and pleural contact, should be assessed carefully to ensure optimal sublobar reselection for patients with stage 1A NSCLC.

References

1. Choe J, Kim MY, Yun JK, et al. Sublobar Resection in Stage IA Non-Small Cell Lung Cancer: Role of Preoperative CT Features in Predicting Pathologic Lymphovascular Invasion and Postoperative Recurrence. AJR Am J Roentgenol. Published May 12, 2021. doi:10.2214/AJR.21.25618

2. CT Promising for Sublobar Resection in Early-Stage Non-Small Cell Lung Cancer. News release.American Roentgen Ray Society. May 13, 2021. Accessed May 21, 2021. https://bit.ly/3vg5fiF