Prediction of and surgical strategy for adherent hilar lymph nodes in thoracoscopic surgery

Adhesions between the hilar lymph nodes (HLN) and pulmonary artery are challenging during thoracoscopic surgery. Preoperative assessment of appropriate surgical access and feasibility of thoracoscopic surgery for lobectomy are crucial. However, there have been only a few reports of this issue. We investigated the association between the radiological features and the presence of HLN adhesions and validated the possibility of preoperatively predicting their presence. The types of adhesions were classified, and surgical strategies for each category were summarized.

We retrospectively identified 19 patients with adherent HLN (group A) from 1134 patients who had undergone thoracoscopic surgery for lobectomy between January 2008 and December 2017. One case in group A was matched to two cases with normal HLN (group N) by propensity score matching. We compared the radiological features of HLN between the two groups on preoperative CT scans. For group A, we assessed the recurrence of regional lymph nodes (RLNs) and classified the types of adhesions.

Adherent HLN were larger and had higher CT values than normal HLN. Calcification in the RLNs indicated the possibility of adhesions in HLN. Group A had adhesions due to inflammation but no postoperative recurrence of RLNs.

Adhesion of HLN to the pulmonary artery may be predicted to some extent by using preoperative CT scans. Our findings may contribute to improving the safety of thoracoscopic surgery.