Three-Dimensional Histologic, Immunohistochemical and Multiplex Immunofluorescence Analysis of Dynamic Vessel Co-Option of Spread Through Air Spaces (STAS) in Lung Adenocarcinoma
Yagi Y, Aly RG, Tabata K, Barlas A, Rekhtman N, Eguchi T, Montecalvo J, Hameed M, Manova-Todorova K, Adusumilli PS, and Travis WD. Three-Dimensional Histologic, Immunohistochemical And Multiplex Immunofluorescence Analysis Of Dynamic Vessel Co-Option Of Spread Through Air Spaces (Stas) In Lung Adenocarcinoma. J Thorac Oncol 2019.
J Thorac Oncol
BACKGROUND: Spread through air spaces (STAS) is a method of invasion in lung adenocarcinoma, associated with tumor recurrence and poor survival. The spatial orientation of STAS cells/clusters to the lung alveolar parenchyma is not known. The aim of this study was to utilize high resolution and high-quality three-dimensional (3D) reconstruction of images from immunohistochemistry (IHC) and multiplex immunofluorescence (IF) experiments to understand the spatial architecture of tumor cell clusters by STAS in the lung parenchyma.
METHODS: Four lung adenocarcinomas: 3 micropapillary (MIP) predominant and 1 solid (SN) predominant adenocarcinoma subtypes, were investigated. A 3D reconstruction image was created from the formalin fixed paraffin-embedded (FFPE) blocks. 350 serial sections were obtained and stained with hematoxylin and eosin (H&E) (100 slides), IHC (200 slides), and multiplex IF (50 slides) with the following antibodies: CD31, collagen type 4, TTF-1 and E-Cadherin. Whole slide images (WSIs) were reconstructed into 3D images for evaluation.
RESULTS: Serial 3D image analysis by H&E as well as IHC and IF showed the MIP clusters and SN nests of STAS focally attached to alveolar walls away from the main tumor.
CONCLUSION: Our 3-D reconstructions demonstrated STAS tumor cells can attach to alveolar walls rather than appearing free floating as seen on 2D sections. This suggests that tumor cells detach from the main tumor, migrate through air spaces and reattach to alveolar walls through vessel co-option allowing them to survive and grow. This may explain the higher recurrence rate and worse survival for STAS positive tumors undergoing limited resection compared to lobectomy.
ePub ahead of print