Correlation between maximal tumor diameter of fresh pathology specimens and computed tomography images in lung adenocarcinoma

Accuracy of solid portion size measured on multiplanar volume rendering images for assessing invasiveness in lung adenocarcinoma manifesting as subsolid nodules

Background

The solid component of subsolid nodules (SSNs) is closely associated with the invasiveness of lung adenocarcinoma, and its accurate assessment is crucial for selecting treatment method. Therefore, this study aimed to evaluate the accuracy of solid component size within SSNs measured on multiplanar volume rendering (MPVR) and compare it with the dimensions of invasive components on pathology.

Methods

A pilot study was conducted using a chest phantom to determine the optimal MPVR threshold for the solid component within SSN, and then clinical validation was carried out by retrospective inclusion of patients with pathologically confirmed solitary SSN from October 2020 to October 2021. The radiological tumor size on MPVR and solid component size on MPVR (RSSm) and on lung window (RSSl) were measured. The size of the tumor and invasion were measured on the pathological section, and the invasion, fibrosis, and inflammation within SSNs were also recorded. The measurement difference between computed tomography (CT) and pathology, inter-observer and inter-measurement agreement were analyzed. Receiver operating characteristic (ROC) analysis and Bland-Altman plot were performed to evaluate the diagnostic efficiency of MPVR.

Results

A total of 142 patients (mean age, 54±11 years, 39 men) were retrospectively enrolled in the clinical study, with 26 adenocarcinomas in situ, 92 minimally invasive adenocarcinomas (MIAs), and 24 invasive adenocarcinomas (IAs). The RSSl was significantly smaller than pathological invasion size with fair inter-measurement agreement [intraclass correlation coefficient (ICC) =0.562, P<0.001] and moderate interobserver agreement (ICC =0.761, P<0.001). The RSSm was significantly larger than pathological invasion size with the excellent inter-measurement agreement (ICC =0.829, P<0.001) and excellent (ICC =0.952, P<0.001) interobserver agreement. ROC analysis showed that the cutoff value of RSSm for differentiating adenocarcinoma in situ from MIA and MIA from IA was 1.85 and 6.45 mm (sensitivity: 93.8% and 95.5%, specificity: 85.7% and 88.2%, 95% confidence internal: 0.914-0.993 and 0.900-0.983), respectively. The positive predictive value-and negative predictive value of MPVR in predicting invasiveness were 92.8% and 100%, respectively.

Conclusions

Using MPVR to predict the invasive degree of SSN had high accuracy and good inter-observer agreement, which is superior to lung window measurements and helpful for clinical decision-making.

Updates on lung adenocarcinoma: invasive size, grading and STAS

Advancements in the classification of lung adenocarcinoma have resulted in significant changes in pathological reporting. The eighth edition of the tumour-node-metastasis (TNM) staging guidelines calls for the use of invasive size in staging in place of total tumour size. This shift improves prognostic stratification and requires a more nuanced approach to tumour measurements in challenging situations. Similarly, the adoption of new grading criteria based on the predominant and highest-grade pattern proposed by the International Association for the Study of Lung Cancer (IASLC) shows improved prognostication, and therefore clinical utility, relative to previous grading systems. Spread through airspaces (STAS) is a form of tumour invasion involving tumour cells spreading through the airspaces, which has been highly researched in recent years. This review discusses updates in pathological T staging, adenocarcinoma grading and STAS and illustrates the utility and limitations of current concepts in lung adenocarcinoma.

Honeycomb lung is a major risk factor for preoperative radiological tumor size underestimation in patients with primary lung cancer

Background

Lung cancer frequently occurs in lungs with background idiopathic interstitial pneumonias (IIPs). Limited resection is often selected to treat lung cancer in patients with IIPs in whom respiratory function is already compromised. However, accurate surgical margins are essential for curative resection; underestimating these margins is a risk for residual lung cancer after surgery. We aimed to investigate the findings of lung fields adjacent to cancer segments affect the estimation of tumor size on computed tomography compared with the pathological specimen.

Methods

This analytical observational study retrospectively investigated 896 patients with lung cancer operated on at Fujita Health University from January 2015 to June 2020. The definition of underestimation was a ≥10 mm difference between the radiological and pathological maximum sizes of the tumor.

Results

The lung tumors were in 15 honeycomb, 30 reticulated, 207 emphysematous, and 628 normal lungs. The ratio of underestimation in honeycomb lungs was 33.3% compared to 7.4% without honeycombing (P=0.004). Multivariate analysis showed that honeycombing was a significant risk factor for tumor size underestimation. A Bland-Altman plot represented wide 95% limits of agreement, -40.8 to 70.2 mm, between the pathological and radiological maximum tumor sizes in honeycomb lungs.

Size Measurement and Segmentectomy Resection Margin of Early-Stage Lung Adenocarcinoma Manifesting on Virtual 3D Imagery and Pathology: A Pilot Correlation Study

Background: The objective of our study was to assess if 3D reconstructed images could be extrapolated to reflect pathologies, as evaluated by early-stage lung adenocarcinoma tumor size and simulated segmentectomy resection margin. Methods: Retrospectively selected patients (n = 18) who underwent segmentectomy at Changhua Christian Hospital between 2012 and 2018 and then had pulmonary 3D reconstruction using Ziostation2 were included in our study. Tumor size and simulated segmentectomy resection distance on a 3D model were measure and compared to pathology. Results: Both tumor size and segmentectomy resection margin showed positive correlations between 3D image measurements and pathological measurements. The resection margin showed a stronger correlation and was beneficial in pre-operative planning. Conclusions: A 3D reconstructed model aided understanding of pulmonary anatomy, prompting confidence in surgical approaches and ensured segmentectomy outcome success. Regardless of age and pulmonary function, 3D simulation can accurately mimic segmentectomy, making it a simple, effective and feasible pre-operative planning tool.

Rates of invasive disease and outcomes in NSCLC patients with biopsy suggestive of carcinoma in situ

INTRODUCTION

Carcinoma in situ is a rare non-invasive histology of non-small cell lung cancer (NSCLC) with excellent survival outcomes with resection. However, management of lung biopsy suggestive of in situ disease remains unclear. To inform decision-making in this scenario, we determined the rate of invasive disease presence upon resection of lesions with an initial biopsy suggestive of purely in situ disease.

METHODS

The study included 960 patients diagnosed with NSCLC from 2003 to 2017 in the National Cancer Database whose workup included a lung biopsy suggestive of in situ disease. Among the cohort who proceeded to resection, we identified the rate of invasive disease discovered on surgical pathology along with significant demographic and clinical contributors to invasion risk. Survival outcomes were measured for the observed cohort that did not receive local therapy after biopsy.

RESULTS

Invasive disease was identified at resection in 49.3 % of patients. Lesion size was associated with risk of invasive disease: 35.7 % for ≤1 cm, 45.2 % for 1-2 cm, 55.7 % for 2-3 cm, and 87.5 % for 3-5 cm (p < 0.001). Of patients with squamous histology, 61.5 % had invasive disease versus 46.5 % with adenocarcinoma histology (p = 0.026). On multivariable logistic regression, invasive disease remained associated with tumor size (OR 1.9 per cm, 95 % CI 1.5-2.4, p < 0.001), and squamous histology (OR 1.8, 95 % CI 1.1-3.2, p = 0.028). Overall survival at 3 years was 51.5 % in the observed cohort.

CONCLUSION

Nearly half of patients with biopsy suggestive of in situ disease had invasive disease at resection. Tumor size and histology are strong predictors of invasive disease and may be used for risk stratification. However, the findings support the practice of definitive therapy whenever feasible.

Benefits of the multiplanar and volumetric analyses of pancreatic cancer using computed tomography

Although pancreatic cancer tumors are irregularly shaped in terms of their three-dimensional (3D) structure, when T staging by imaging results, generally only the axial plane is used to measure the largest tumor diameter. We investigated the size of pancreatic cancer tumors using multi-plane and 3D reconstructed computed tomography (CT) images and investigated their clinical usefulness. Patients who underwent surgery for pancreatic adenocarcinoma were included. We measured the largest diameter of each pancreatic tumor in the axial, coronal, and sagittal planes of CT images. In addition, maximal diameter and cancer volume were measured from 3D images that were constructed using a semi-automated software system. Final data were compared with pathologic examination and the effect of each value on prognosis was analyzed. A total of 183 patients were analyzed. The maximal diameters measured on the axial, coronal, and sagittal planes were 2.9 ± 1.1, 3.2 ± 0.9, and 3.2 ± 1.0 cm, respectively, which were significantly smaller than pathologic results (3.4 ± 1.4 cm, all p<0.05 by paired t-test). The longest diameter among them (3.4 ± 1.1 cm) was nearly similar to the pathologic diameter. Cancer volume measured on 3D images demonstrated a higher area under the receptor operating characteristic curve [0.714, (95% confidence interval: 0.640-0.788)] for predicting early death compared to any unidimensional CT diameters measured. The longest pancreatic tumor diameter measured on multiplanar CT images was most accurate when compared to its corresponding pathologic diameter. Tumor volume had a stronger correlation with overall survival than tumor diameter.

The progression of non-small cell lung cancer from diagnosis to surgery

OBJECTIVES

The IASLC 8th TNM Staging 8th differentiates between a greater number of T-stages. Resection remains the mainstay of curative treatment with often significant waiting times. This study aims to quantify the T-stage progression and growth of non-small cell lung cancers (NSCLCs) between radiological diagnosis and resection, and its impact on disease recurrence and survival.

MATERIALS AND METHODS

A retrospective analysis of NSCLC resections (289) in a high-volume centre between July 01, 2015 and June 30, 2016. Baseline demographics, time from diagnostic CT to surgery, tumour size (cm) and T-stage from diagnostic CT, PET-CT and post-operative histopathology reports were recorded. The primary outcome was increase in T-stage from diagnostic CT to resection. Kaplan-Meier and cox proportional hazard analyses were used to determine recurrence-free survival and survival.

RESULTS

Median increase in tumour size between diagnosis and resection was 0.3 cm (p < 0.0001). Median percentage increase in size was 13%. T-stage increased in 133 (46.0%) patients. N stage increased in 51 patients (17.7%), 32 (11.1%) to N2 disease. Mean survival in those upstaged was 43.5 (39.9-47.1) months versus 53.4 (50.0-56.8) months in patients not upstaged (p = 0.025). Mean recurrence-free survival in those upstaged was 39.1 (35.2-43.0) months versus 47.7 (43.9-51.4) months in patients not upstaged (p = 0.117). Upstaging was independently associated with inferior survival (HR 1.674, p = 0.006) and inferior recurrence-free survival (HR 1.423, p = 0.038).

CONCLUSIONS

A significant number of patients are upstaged between diagnostic and resection resulting in reduced survival and recurrence-free survival. A change in management pathways are required to improve outcomes in NSCLC.