Volume and Mass Doubling Time of Lung Adenocarcinoma according to WHO Histologic Classification

Abstract

Objective This study aimed to evaluate the tumor doubling time of invasive lung adenocarcinoma according to the International Association of the Study for Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) histologic classification. Materials and Methods Among the 2905 patients with surgically resected lung adenocarcinoma, we retrospectively included 172 patients (mean age, 65.6 ± 9.0 years) who had paired thin-section non-contrast chest computed tomography (CT) scans at least 84 days apart with the same CT parameters, along with 10 patients with squamous cell carcinoma (mean age, 70.9 ± 7.4 years) for comparison. Three-dimensional semiautomatic segmentation of nodules was performed to calculate the volume doubling time (VDT), mass doubling time (MDT), and specific growth rate (SGR) of volume and mass. Multivariate linear regression, one-way analysis of variance, and receiver operating characteristic curve analyses were performed. Results The median VDT and MDT of lung cancers were as follows: acinar, 603.2 and 639.5 days; lepidic, 1140.6 and 970.1 days; solid/micropapillary, 232.7 and 221.8 days; papillary, 599.0 and 624.3 days; invasive mucinous, 440.7 and 438.2 days; and squamous cell carcinoma, 149.1 and 146.1 days, respectively. The adjusted SGR of volume and mass of the solid-/micropapillary-predominant subtypes were significantly shorter than those of the acinar-, lepidic-, and papillary-predominant subtypes. The histologic subtype was independently associated with tumor doubling time. A VDT of 465.2 days and an MDT of 437.5 days yielded areas under the curve of 0.791 and 0.795, respectively, for distinguishing solid-/micropapillary-predominant subtypes from other subtypes of lung adenocarcinoma. Conclusion The tumor doubling time of invasive lung adenocarcinoma differed according to the IASCL/ATS/ERS histologic classification.

Consecutive Serial Non-Contrast CT Scan-Based Deep Learning Model Facilitates the Prediction of Tumor Invasiveness of Ground-Glass Nodules

“…Previous studies have reported that the size of GGNs is a critical risk factor for potential invasiveness (3)(4)(5)21). Lee et al found that the optimal cutoff size for preinvasive lesions was less than 10 mm (sensitivity, 53.33%; specificity, 100%) in a pure GGN cohort; this could be used as a selection criterion to identify patients suitable for sublobar resection (25).…”

“…We combined baseline and 3-month follow-up continuous CT scan images to obtain the original features and changed features that maximized the risk of tumor invasion. Recently, numerous studies and guidelines have advocated that early follow-up of patients with GGN should replace unnecessary surgical resection (3,5,19). However, subtle changes between the short-term follow-up images and the baseline CT images are often invisible to mostly radiologists, hence the need to evaluate invasiveness using DL algorithms.…”

“…Most previous CT-based quantitative studies have used single screening images to estimate the invasiveness of GGNs on the basis of size, density, and mass volume (4,5). However, there are known limitations to this approach owing to inter-and intraobserver variability in morphological features of GGNs.…”

Lung Cancer Stage Shift as a Result of COVID-19 Lockdowns in New York City, a Brief Report

“…Within thoracic oncology, computed tomographic (CT) quantification of volume-doubling time (VDT) has been used as a means to measure the presumed exponential nature of lung cancer growth grossly, in order to better understand time to progression 13 , 14 . VDT varies by methodology and histologic type but a recent study by Hong et al places the VDT of squamous cell carcinoma at 149 days (∼21 weeks) and adenocarcinoma ranging by subtype from 232 days or ∼33 weeks (solid/micropapillary) to 1140 days or ∼ 163 weeks (lepidic) 15 . While 21 weeks is likely much longer than any experienced delay during the lockdown, it certainly puts context to the minimum of 11 weeks delay that many New Yorkers may have experienced.…”

The Natural Growth Rate of Growing Malignant Pulmonary Nodules with Ground-Glass Opacity and Association of Clinic Features With It

“…The patients with the following characteristics (Fig. 1) will be selected in this study, including (1) GGN was identi ed by a pathology, (2) pulmonary nodules were regarded as pure GGOs or part-solid GGOs based on the chest CT examination with slice thickness less than 1.25 mm, (3) the GGN was at least twice determined by chest CT scanning with an interval of over 30 days [20] , and (4) either the density, volume, or mass of GGN, estimated by the CT embedded software, was increasing, i.e., the GNN was growing. Only the largest size of GGN was recorded if multiple GNNs were detected from a patiented, these patients also included.…”