Preoperative three-dimensional lung volumetry predicts respiratory complications in patients undergoing major liver resection for colorectal metastases

Abstract

Colorectal liver metastases (CRLM) are the predominant factor limiting survival in patients with colorectal cancer and liver resection with complete tumor removal is the best treatment option for these patients. This study examines the predictive ability of three-dimensional lung volumetry (3DLV) based on preoperative computerized tomography (CT), to predict postoperative pulmonary complications in patients undergoing major liver resection for CRLM. Patients undergoing major curative liver resection for CRLM between 2010 and 2021 with a preoperative CT scan of the thorax within 6 weeks of surgery, were included. Total lung volume (TLV) was calculated using volumetry software 3D-Slicer version 4.11.20210226 including Chest Imaging Platform extension ( http://www.slicer.org ). The area under the curve (AUC) of a receiver-operating characteristic analysis was used to define a cut-off value of TLV, for predicting the occurrence of postoperative respiratory complications. Differences between patients with TLV below and above the cut-off were examined with Chi-square or Fisher's exact test and Mann-Whitney U tests and logistic regression was used to determine independent risk factors for the development of respiratory complications. A total of 123 patients were included, of which 35 (29%) developed respiratory complications. A predictive ability of TLV regarding respiratory complications was shown (AUC 0.62, p = 0.036) and a cut-off value of 4500 cm³ was defined. Patients with TLV < 4500 cm³ were shown to suffer from significantly higher rates of respiratory complications (44% vs. 21%, p = 0.007) compared to the rest. Logistic regression analysis identified TLV < 4500 cm³ as an independent predictor for the occurrence of respiratory complications (odds ratio 3.777, 95% confidence intervals 1.488-9.588, p = 0.005). Preoperative 3DLV is a viable technique for prediction of postoperative pulmonary complications in patients undergoing major liver resection for CRLM. More studies in larger cohorts are necessary to further evaluate this technique.

Keywords: Colorectal liver metastases; Hepatobiliary; Lung volumetry; Respiratory complications; Surgery.

Figure 1

Three-dimensional computer-tomography-based lung volumetry of a male patient. (A) axial view; (B) Three-dimensional model of the respiratory system; (C) coronal view; (D) sagittal view. Green shading: right lung; Yellow shading: left lung; Blue shading: trachea with main bronchi; Total lung volume calculated as the sum of the right and left lung volumes.

Figure 2

Flowchart of inclusion and exclusion criteria, leading to the final study population. Abbreviations: CRLM, colorectal liver metastases; CT, Computerised Tomography.

Figure 3

Receiver operating characteristic (ROC) curve of the main cohort: Total lung volume can predict postoperative respiratory complications. Abbreviations: AUC, Area Under the Curve.