Prognostic Significance of Tumor Size of Small Lung Adenocarcinomas Evaluated with Mediastinal Window Settings on Computed Tomography

Abstract

BackgroundWe aimed to clarify that the size of the lung adenocarcinoma evaluated using mediastinal window on computed tomography is an important and useful modality for predicting invasiveness, lymph node metastasis and prognosis in small adenocarcinoma.MethodsWe evaluated 176 patients with small lung adenocarcinomas (diameter, 1–3 cm) who underwent standard surgical resection. Tumours were examined using computed tomography with thin section conditions (1.25 mm thick on high-resolution computed tomography) with tumour dimensions evaluated under two settings: lung window and mediastinal window. We also determined the patient age, gender, preoperative nodal status, tumour size, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and pathological status (lymphatic vessel, vascular vessel or pleural invasion). Recurrence-free survival was used for prognosis.ResultsLung window, mediastinal window, tumour disappearance ratio and preoperative nodal status were significant predictive factors for recurrence-free survival in univariate analyses. Areas under the receiver operator curves for recurrence were 0.76, 0.73 and 0.65 for mediastinal window, tumour disappearance ratio and lung window, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant predictive factors for lymph node metastasis in univariate analyses; areas under the receiver operator curves were 0.61, 0.76, 0.72 and 0.66, for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant factors for lymphatic vessel, vascular vessel or pleural invasion in univariate analyses; areas under the receiver operator curves were 0.60, 0.81, 0.81 and 0.65 for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively.ConclusionsAccording to the univariate analyses including a logistic regression and ROCs performed for variables with p-values of <0.05 on univariate analyses, our results suggest that measuring tumour size using mediastinal window on high-resolution computed tomography is a simple and useful preoperative prognosis modality in small adenocarcinoma.

Estimation of the pathological invasive size of pulmonary adenocarcinoma using high-resolution computed tomography of the chest: A consideration based on lung and mediastinal window settings

“…Several studies of PADC have reported that lesions eliminating ground glass opacity on HRCT images and those excluding lepidic growth lesions on pathology examination correlated with prognosis after resection [4][5][6][7][8][9][10][11][12]16,17]. However, there are only a few studies on the use of HRCT images to preoperatively estimate the newly proposed pathological invasive size of PADC.…”

“…Some studies suggested that the degree of invasion and the prognosis after resection are correlated with the tumor disappearance ratio on chest HRCT, that is, the ratio of tumor dimension in the mediastinal window setting to the whole tumor dimension in the lung window setting [4][5][6]. Other studies suggested that the degree of invasion and the prognosis after resection are correlated with the solid part of the tumor in the lung window setting [7][8][9][10] or with absolute values of the whole-tumor dimension in the mediastinal window setting [11,12].…”

The IASLC Lung Cancer Staging Project: Proposals for Coding T Categories for Subsolid Nodules and Assessment of Tumor Size in Part-Solid Tumors in the Forthcoming Eighth Edition of the TNM Classification of Lung Cancer

“…This method has been called the tumor disappearance rate or ratio. 24,[98][99][100] This is important because it has been shown that measuring the solid component of subsolid nodules correlates best with the likelihood of tumor invasion. Furthermore, use of narrow (mediastinal) windows facilitates demonstration of both the increasing overall tumor density and the increasing size of any solid components over time.…”

Challenges for real‐time intraoperative diagnosis of high risk histology in lung adenocarcinoma: A necessity for sublobar resection

“…Approximately 25% of cases detected at an early‐stage are candidates for surgical resection . Tumor size and nodal metastasis are well‐known prognostic factors in resected early‐stage lung ADC and one of the major factors that is considered in the treatment strategy. Additionally, given the advancing age of many patients diagnosed with lung ADC, there is a more prevalent risk for significant comorbidities in the aged population .…”