CT features of pulmonary ACTH-Secreting Tumor

Abstract

The purpose of the study is to improve the accuracy of CT diagnostics of pulmonary ACTH-Secreting Tumor.Material and methods. During the period from 2010 to 2022 at the Endocrinology Research Centre and the National Medical Research Center of Surgery named after A. Vishnevsky of the Ministry of Health of Russia 23 patients with pulmonary ACTH-Secreting Tumor were examined and treated. CT-features were analyzed: localization, shape, contours, connection of the formation with the bronchus, connection of the formation with the vessel, adherence to the vessel and bronchus along the long axis, structure of the neoplasm. We also analyzed the largest size of the formation, the size of the largest regional lymph node, the density of the tumor on axial sections in the native, arterial, venous and delayed phases of the study.Results. In the study, we identified a new phenotypic CT sign – the relationship with the bronchovascular bundle. The connection with the bronchus and vessel was assessed in detail. In the majority of patients, the connection with the pulmonary vessels (in most cases with small bronchial arteries) was especially clearly noted: an intimate attachment of the tumor along its long axis to the vessel. Less often it was possible to trace the connection with the bronchus.Conclusion. ACTH-producing NET of the lung is most often a peripherally located oval-shaped formation with even/ lobulated contours, adjacent to the bronchovascular bundle along the long axis of the tumor, intensively enchancing (increase of density parameters by more than 40 HU compared with the unenhanced phase) in the venous, less often the arterial phase of bolus contrast enhancement.