Intrapulmonary Lymph Nodes in Patients with Extrapulmonary Solid Tumors

Purpose: To clarify the possibility of metastatic lesions of intrapulmonary lymph nodes in patients with malignant neoplasms of extrapulmonary localization by analyzing retrospective and prospective material.Material and methods: Our study included 139 patients. The criterion for selecting patients was a morphologically confirmed on­cological diagnosis and the presence of lesions in the lungs. Patients were recruited from two large groups of leading localizations in the general structure of cancer incidence: a group of patients with colorectal cancer — 76 (54.7 %) and a group of patients with malignant breast tumors — 63 (45.3 %). A total of 312 lung lesions were identified and analyzed in 139 patients. High-resolution computed tomography with a slice thickness of up to 1-1.5 mm of the chest was performed in all patients. Assessment of dynamics in all patients was carried out for at least 3 years.Results: As a result, out of 139 patients with newly detected lesions in the lungs, 43 (30.9 %) patients had lesions identified, which we classified as intrapulmonary regional lymph nodes (RLNs). A total of 75 (24.0 %) lesions classified as typical or atypical RLNs were identified. We obtained the following data: RLNs were located predominantly in the lower lobes — 46.7 %, 84 % of RLNs were localized below the carina. A total of 37.3 % of lesions were classified as perifissural lesions, 62.7 % of identified lesions were classified as subpleural (peripleural) lesions. It was found that the RLNs were localized on the pleura or had a connection with it through a thin septum — 49.3 % and 38.7 %, respectively. The average diameter of the RLN in the lung was 4.0 mm. RLNs were triangular in shape in 64 %, round (lenticular) in 21.3 %, and oval in 14.7 % of cases. 96 % of the lesions we classified as RLN were monitored over time using HRCT for 3 years or more, 4 % of the lesions underwent surgical treatment. All the lesions that we observed over the course of 3 years remained without dynamics. Based on the data obtained, we concluded that RLNs in patients with solid tumors of extrapulmonary locations and lesions in the lungs are benign changes and do not require dynamic monitoring.Conclusions: Lesions in patients with solid tumors of extrapulmonary localization classified as RLN are benign changes and do not affect the stage and nature of the treatment, and also do not require dynamic monitoring.