Prognostic value of the frequency of vascular invasion in stage I non-small cell lung cancer

Preoperative CT Radiomics Nomogram for Predicting Microvascular Invasion in Stage I Non-Small Cell Lung Cancer

RATIONALE AND OBJECTIVES: This study aims to develop and validate a nomogram integrating clinical-CT and radiomic features for preoperative prediction of microvascular invasion (MVI) in patients with stage I non‑small cell lung cancer (NSCLC).

MATERIALS AND METHODS

This retrospective study analyzed 188 cases of stage I NSCLC (63 MVI positives and 125 negatives), which were randomly assigned to training (n = 133) and validation cohorts (n = 55) at a ratio of 7:3. Preoperative non-contrast and contrast-enhanced CT (CECT) images were used to analyze computed tomography (CT) features and extract radiomics features. The student's t-test, the Mann-Whitney-U test, the Pearson correlation, the least absolute shrinkage and selection operator, and multivariable logistic analysis were used to select the significant CT and radiomics features. Multivariable logistic regression analysis was performed to build the clinical-CT, radiomics, and integrated models. The predictive performances were evaluated through the receiver operating characteristic curve and compared with the DeLong test. The integrated nomogram was analyzed regarding discrimination, calibration, and clinical significance.

RESULTS

The rad-score was developed with one shape and four textural features. The integrated nomogram incorporating radiomics score, spiculation, and the number of tumor-related vessels (TVN) demonstrated better predictive efficacy than the radiomics and clinical-CT models in the training cohort (area under the curve [AUC], 0.893 vs 0.853 and 0.828, and p = 0.043 and 0.027, respectively) and validation cohort (AUC, 0.887 vs 0.878 and 0.786, and p = 0.761 and 0.043, respectively). The nomogram also demonstrated good calibration and clinical usefulness.

CONCLUSION

The radiomics nomogram integrating the radiomics with clinical-CT features demonstrated good performance in predicting MVI status in stage I NSCLC. The nomogram may be a useful tool for physicians in improving personalized management of stage I NSCLC.

Intratumoral and peritumoral radiomics nomograms for the preoperative prediction of lymphovascular invasion and overall survival in non-small cell lung cancer

OBJECTIVES

To evaluate the predictive value of intratumoral and peritumoral radiomics and radiomics nomogram for preoperative lymphovascular invasion (LVI) status and overall survival (OS) in patients with non-small cell lung cancer (NSCLC).

METHODS

In total, 240 NSCLC patients from our institution were randomly divided into the training cohort (n = 145) and internal validation cohort (n = 95) with a ratio of 6:4, and 65 patients from the Cancer Imaging Archive were enrolled as the external validation cohort. We extracted 1217 CT-based radiomics features from the gross tumor volume (GTV) and gross tumor volume incorporating peritumoral 3, 6, and 9 mm regions (GPTV₃, GPTV₆, GPTV₉). A radiomics nomogram based on clinical independent predictors and radiomics score (Radscore) of the best radiomics model was constructed. The correlation between factors and OS was evaluated with the Kaplan-Meier survival analysis and Cox proportional hazards regression analysis.

RESULTS

Compared with GTV, GPTV₃, and GPTV₆ radiomics models, GPTV₉ radiomics model exhibited better prediction performance with the AUCs of 0.82, 0.75, and 0.67 in the training, internal validation, and external validation cohorts, respectively. In the clinical model, smoking and clinical stage were independent predictors. The nomogram incorporating independent predictors and GPTV₉-Radscore was clinically useful, with the AUCs of 0.89, 0.83, and 0.66 in three cohorts. Pathological LVI, GPTV₉-Radscore-predicted, and Nomoscore-predicted LVI were associated with poor OS (p < 0.05).

CONCLUSIONS

CT-based radiomics nomogram can predict LVI and OS in patients with NSCLC and may help in making personalized treatment strategies before surgery.

KEY POINTS

• Compared with GTV, GPTV₃, and GPTV₆ radiomics models, GPTV₉ radiomics model showed better prediction performance for LVI status in NSCLC. • The radiomics nomogram based on GPTV₉ radiomics features and clinical independent predictors could effectively predict LVI status and OS in NSCLC and outperformed the clinical model. • The radiomics nomogram had a wider scope of clinical application.

Hemangiosis carcinomatosa as an independent risk factor for long-term survival in Non-Small Cell Lung Cancer patients

OBJECTIVES

Recent studies have shown that blood vessel invasion (V1) influences the long-term survival of patients with Non-Small Cell Lung Cancer (NSCLC). The aim of the present study was to emphasize V1 as an independent risk factor. We evaluated the effects of V1 on the survival of NSCLC patients with UICC stages I, II, and III after surgery.

METHODS

This retrospective study includes 747 consecutive patients with NSCLC who underwent anatomic resection and radical lymphadenectomy at our institution between January 2012 and December 2020. V1- were compared to V0-patients (no blood vessel invasion). All patients received adjuvant therapy according to European guidelines when indicated. After excluding patients with detection of lymphangiosis carcinomatosa, tumor-cells at the resection margin, distant metastases and those, that received neoadjuvant therapy, 1-, 3- and 5- year survival rates were assessed by Kaplan-Meier method. To proof V1 as an independent risk factor, a propensity score matched (PSM) analysis was performed regarding age, gender, UICC-stage, lymph-node involvement, and comorbidities.

RESULTS

A total of 461 patients (V0: 440; V1: 21) were included in this analysis. Baseline characteristics did not show any significant difference. Mean age in V0-group was 65.7 ± 10.5 years and 64.1 ± 8.6 years in V1-group (p-value = 0.5). In the V0-group 54.8% were male, whereas in the V1-group this number was 66.7% (p-value = 0.37). Mean survival in V1-group was significantly shorter compared to V0-group (V1: 45.8 ± 9.3 months; V0: 81.1 ± 1.1 months; p-value<0.001). This was confirmed after applying a propensity score matched analysis (V0: 99.9 ± 4.9 months; V1: 45.8 ± 9.3 months; p-value<0.001) - V1 is a prognostic marker independent of UICC stage. The 1-, 3- and 5-year survival rates were significantly shorter for V1-patients (1-year: V0: 100%; V1: 70.6%; p-value = 0.012) (3-year: V0: 95.2%; V1: 46.2%; p-value = 0.002) (5-year: V0: 90.5%; V1: 36.4%; p-value = 0.003).

CONCLUSION

As we have shown with our investigations, V1 has a major impact on long-term survival in NSCLC patients and furthermore, acts as an independent risk factor. Due to our small but specified sample size, our statement should be confirmed by a multicenter study. In the meantime, we suggest making the implementation of the V0/V1 specification mandatory in the tumor classification.

Ground Glass Opacity and Adjuvant Chemotherapy in Pathological Stage IB-IIA Lung Adenocarcinoma

Background

The prognostic value of ground glass opacity (GGO) in stage IA non-small cell lung cancer (NSCLC) has been widely recognized. However, studies investigating its value in the related stage IB-IIA lung adenocarcinoma (LUAD) remains lacking. The impact of adjuvant chemotherapy (ACT) on pathological stage IB-IIA LUAD is also controversial.

Materials and Methods

We retrospectively reviewed the clinical records of 501 patients with pathological stage IB-IIA LUAD at the Sun Yat-sen University Cancer Center from January 2008 to June 2018. We calculated and compared survival curves using the Kaplan-Meier test and log-rank test. Cox regression models were performed to determine independent prognostic factors of disease-free survival (DFS) and overall survival (OS). We established nomograms to predict the OS and DFS of LUAD patients. Calibration and receiver operator characteristic curves were conducted to assess the predictive performance of two nomograms. Based on the nomogram, we identified candidate patients that may most benefit from ACT after surgery.

Results

The number of patients with pure solid, part GGO, and pure GGO nodules was 240, 242, and 19, respectively, and 125 patients who received ACT. Patients with consolidation-to-tumor ratio (CTR) <0.75 had longer OS (P = 0.026) and DFS (P = 0.003). Pathological tumor size and at least 10 lymph nodes (LNs) resection were independent prognostic factors of both OS and DFS. CTR <0.75 was positively associated with DFS. The C-index of nomograms predicting individual OS and DFS was 0.660 and 0.634, respectively. Based on the nomogram for OS, ACT was found to be a positive prognostic indicator of OS (P = 0.031, HR = 0.5141, 95% CI 0.281-0.942) in patients with nomogram total points ≥5.

Conclusion

CTR <0.75 is associated with a better DFS in patients with stage IB-IIA LUAD. Nomograms developed by integrating pathological tumor size, at least 10 LNs resection, and CTR ≥0.75 for predicting individual OS and DFS displayed a good predictive capacity and clinical value, which were also proved to be a useful tool for selecting patients most benefiting from ACT.

Risk stratification and adjuvant chemotherapy after radical resection based on the clinical risk scores of patients with stage IB-IIA non-small cell lung cancer

INTRODUCTION

Despite the heterogeneity among patients with stage IB-IIA non-small cell lung cancer (NSCLC), clinically applicable models to identify patients most suitable for receiving adjuvant chemotherapy (ACT) are limited. We aimed to develop a model for risk stratification and the individualized application of ACT.

METHODS

Between January 2008 and March 2018, patients with T2N0M0 NSCLC at Sun Yat-sen University Cancer Center were retrospectively enrolled. Survival curves were estimated by Kaplan-Meier method and compared with log-rank test. Cox regression models were used to identify prognostic factors for disease-free survival (DFS) and overall survival (OS). Propensity score matching (PSM) was implemented. Subgroup analysis was performed based on clinical risk score (CRS) value and epidermal growth factor receptor (EGFR) mutation status.

RESULTS

Of 1063 patients with T2N0 NSCLC enrolled, 272 patients received ACT. Before PSM, patients with high CRS (>1) had a significantly worse OS and DFS outcomes. In the PSM, the baseline characteristics of the 270 pairs of patients were well matched. ACT was associated with improved OS outcomes for patients with a high CRS, while ACT was associated with improved OS and DFS outcomes in patients with wild-type EGFR. The interaction analysis showed an apparent interaction effect between ACT and EGFR-activating mutations as well as chemotherapy regimens and histology.

CONCLUSIONS

The CRS can predict the prognosis of patients with stage IB-IIA NSCLC. ACT could improve the outcome of patients with a high CRS. Patients with non-squamous cell histology receiving pemetrexed plus platinum might benefit more, but not those with EGFR-activating mutations.

Blood Vessel Invasion Predicts Postoperative Survival Outcomes and Systemic Recurrence Regardless of Location or Blood Vessel Type in Patients with Lung Adenocarcinoma

BACKGROUND

Presence of blood vessel invasion (BVI) is one of the prognostic indicators for lung cancer patients with surgical resection. However, prognostic roles of the location and the type of the involved blood vessel have not been fully evaluated yet.

PATIENTS AND METHODS

We retrieved the data of 217 cases of surgically resected lung adenocarcinoma from Asan Medical Center. Clinicopathologic features, including BVI, were reassessed. The location (tumor center and/or periphery) and involved blood vessel types (large and/or small vessels; arteries and/or veins) of BVI were separately examined on standard hematoxylin-eosin slides and confirmed by van Gieson elastic staining.

RESULTS

BVI was identified in 35% of cases (76/217), with the tumor center (intratumoral) as the location in more than half of the cases (42/76, 55.3%). The presence of BVI was significantly associated with higher pathologic stage, increased size of invasive components, frequent pleural invasion, lymphatic permeation, and spread through alveolar spaces. BVI was significantly associated with poor overall survival (OS) and recurrence-free survival (RFS) both in univariate and multivariate survival analyses [for OS, hazard ratio (HR) 1.92, 95% confidence interval (CI) 1.06-3.48, P = 0.031; for RFS, HR 2.65, 95% CI 1.64-4.28; P < 0.001]. BVI subgroups, according to location and type of the involved blood vessels, invariably displayed significantly poor RFS; however, the results for OS varied.

CONCLUSION

Regardless of their location or blood vessel type, presence of BVI is a useful predictor for postoperative survival outcomes, which should be carefully evaluated on pathologic examination.

[Prognostic Factors of N2 Stage Non-small Cell Lung Cancer after Surgery]

背景与目的

N2期非小细胞肺癌患者预后异质性很强，本研究旨在探索其预后相关因素。

方法

纳入四川大学华西医院胸外科2007年1月-2016年12月间行根治性切除的N2期患者，使用Cox模型比较临床病理学特征与总体生存率之间的关系，使用Kaplan-Meier法绘制生存曲线，并且根据淋巴结转移情况进行亚组分析。

结果

总共纳入773例N2期患者，中位随访时间57.2个月，5年总体生存率为34.8%。肿瘤原发灶-淋巴结-远处转移（tumor-node-metastasis, TNM）分期、多站淋巴结转移、跳跃性转移、脉管侵犯、辅助化疗为预后相关的独立风险因素。T1-3期患者具有相似的预后，T4期患者预后明显更差。单站跳跃性转移的患者预后最好，5年生存率达48.9%。

结论

N2患者中T4期预后差。在将来的分期中应结合淋巴结转移站数和跳跃性转移进行更精细的N分期划分。

Lung Cancer Staging

Lung cancer staging is a foundation of patient care, informing management decisions and prognosis. This comprehensive overview of the current 8th edition American Joint Committee on Cancer Cancer Staging Manual addresses common difficulties in staging, such as measuring the invasive component of adenocarcinomas and staging multiple lung nodules.

Risk analyses of N2 lymph-node metastases in patients with T1 non-small cell lung cancer: a multi-center real-world observational study in China

PURPOSE

N2 lymph-node metastases occur in approximately 6-17% of the patients with T1-2 non-small cell lung cancer (NSCLC). However, the clinical characteristics of N2 patients are not fully understood.

METHODS

This retrospective, multi-center analysis included T1 NSCLC patients receiving surgical resection during a period from Jan 2nd, 2014 to Dec 27th, 2017. The diagnosis was pathologically verified in all cases. Univariate and multivariate logistic regression analyses were conducted to analyze the factors that are associated with pN2 lymph-node metastases.

RESULTS

A total of 10,885 patients (48.4% men; 84.7% adenocarcinoma) were included in the analysis. The mean age was 59.0 ± 9.9 years. The mean tumor size was 1.8 ± 0.8 cm. Of the patients, 3260 (29.9%) were smokers or ex-smokers. Lymph-node metastases were verified in 1808 (16.6%) patients, and 1167 (10.7%) patients had N2 lymph-node metastases. The multivariate analyses indicated that larger tumor size, lower differentiation, CEA level ≥ 5 ng/mL, vascular invasion (+), and pleural involvement (+) were associated with higher percentages of N2 lymph-node metastases (p < 0.001 for all).

CONCLUSIONS

This study demonstrated the significant association between N2 lymph-node metastases and tumor size and differentiation, CEA levels, and status of vascular invasion and pleural involvement.

Tenascin-C increases lung metastasis by impacting blood vessel invasions

Metastasis is a major cause of death in cancer patients. The extracellular matrix molecule tenascin-C is a known promoter of metastasis, however the underlying mechanisms are not well understood. To further analyze the impact of tenascin-C on cancer progression we generated MMTV-NeuNT mice that develop spontaneous mammary tumors, on a tenascin-C knockout background. We also developed a syngeneic orthotopic model in which tumor cells derived from a MMTV-NeuNT tumor. Tumor cells were transfected with control shRNA or with shRNA to knockdown tenascin-C expression and, were grafted into the mammary gland of immune competent, wildtype or tenascin-C knockout mice. We show that stromal-derived tenascin-C increases metastasis by reducing apoptosis and inducing the cellular plasticity of cancer cells located in pulmonary blood vessels invasions (BVI), before extravasation. We characterized BVI as organized structures of tightly packed aggregates of proliferating tumor cells with epithelial characteristics, surrounded by Fsp1+ cells, internally located platelets and, a luminal monolayer of endothelial cells. We found extracellular matrix, in particular, tenascin-C, between the stromal cells and the tumor cell cluster. In mice lacking stromal-derived tenascin-C, the organization of pulmonary BVI was significantly affected, revealing novel functions of host-derived tenascin-C in supporting the integrity of the endothelial cell coat, increasing platelet abundance, tumor cell survival, epithelial plasticity, thereby promoting overall lung metastasis. Many effects of tenascin-C observed in BVI including enhancement of cellular plasticity, survival and migration, could be explained by activation of TGF-β signaling. Finally, in several human cancers, we also observed BVI to be surrounded by an endothelial monolayer and to express tenascin-C. Expression of tenascin-C is specific to BVI and is not observed in lymphatic vascular invasions frequent in breast cancer, which lack an endothelial lining. Given that BVI have prognostic significance for many tumor types, such as shorter cancer patient survival, increased metastasis, vessel occlusion, and organ failure, our data revealing a novel mechanism by which stromal tenascin-C promotes metastasis in human cancer, may have potential for diagnosis and therapy.

Intensity of SLX predicts distance of tumor spread through alveolar spaces in stage I lung adenocarcinoma

Background

Tumor spread through alveolar spaces (STAS) is a recently described invasive pattern associated with the prognosis and recurrence of lung adenocarcinoma. This study was performed to determine whether the presence and distance of STAS can be predicted by the immunohistochemical intensity of SLX, a well‐known cell adhesion protein.

Methods

In total, 245 patients with pathological stage I lung adenocarcinoma who underwent lobectomy with radical mediastinal lymph node dissection were identified from 1998 to 2012. Recurrence‐free survival (RFS) was compared between patients stratified by STAS and the immunohistochemical intensity of SLX in the main tumor. Patients were divided into three groups based on the intensity of SLX staining: high (n = 108), moderate (n = 48), and low (n = 89).

Results

STAS was observed in 71 patients (29.0%). Patients with STAS had significantly poorer five‐year RFS (67.1%) than those without STAS (84.8%). Although no relationship was observed between the existence of STAS and SLX intensity, the distance between STAS cells and the main tumor was significantly shorter in the moderate group (median 0.9 mm, range: 0.2–1.2 mm) than in the other two groups (median 1.2 mm, range: 0.4–5.0 mm). The five‐year RFS rates in the high, moderate, and low groups were 80.0%, 96.0%, and 75.8%, respectively. Multivariate analysis revealed that pathological stage, lymphatic/vascular invasion, and SLX intensity were independent predictors of recurrence.

Conclusion

SLX staining cannot predict the presence of STAS; however, it can predict the distance between STAS and the main tumor in stage I lung adenocarcinoma.

Elevated MACC1 expression predicts poor prognosis in small invasive lung adenocarcinoma

BACKGROUND

Patients with small (⩽ 2 cm) invasive lung adenocarcinoma are at high risk of poor prognosis and disease recurrence after complete surgical resection. Therefore, identification of high-risk individuals from these patients emerges as an urgent problem. Elevated MACC1 expression predicts a poor prognosis in multiple types of cancer that are independent of TNM staging. This study investigated the prognostic value of MACC1 expression in patients with small invasive lung adenocarcinoma.

OBJECTIVE

The current study aimed to evaluate the relationship between MACC1 expression in patients' tumor tissue and prognosis in small invasive lung adenocarcinoma.

METHODS

The records of 131 patients with small invasive lung adenocarcinoma who underwent complete surgical resection were reviewed. The MACC1 expression was detected by immunohistochemical staining in all specimens. Meanwhile, western blot and real-time quantitative PCR were used to examine the expression level of MACC1 in human lung adenocarcinoma cell lines. The effect of clinicopathological risk factors on patients' survival was analyzed using the Kaplan-Meier approach and multivariable Cox models.

RESULTS

Elevated MACC1 expression was observed in 53 (40.5%) specimens, and in A549, H358, H460 and H322 lung adenocarcinoma cell lines. MACC1 overexpression was associated with differentiation (P= 0.005) and blood vessel invasion (P= 0.001). Compared with low MACC1 expression, elevated MACC1 expression was associated with significantly shorter overall survival (odds ratio = 6.515; 95% confidence interval: 1.382-30.721; P= 0.018) and disease-free survival (odds ratio = 3.270; 95% confidence interval: 1.117-9.569; P= 0.031). Multivariate analyses demonstrated high MACC1 expression is an independent risk factor of worse overall survival (odds ratio = 5.684; 95% confidence interval: 1.145-28.210; P= 0.034) and disease-free survival (odds ratio = 4.667; 95% confidence interval: 1.372-15.877; P= 0.014).

CONCLUSION

MACC1 is an independent prognostic marker in patients with small invasive lung adenocarcinoma after complete surgical resection. Differential outcomes are associated with MACC1 expression level.

Preoperative bronchoscopic cancer confirmation does not increase risk of recurrence in stage1A non-small cell lung cancer

OBJECTIVE

This study was conducted to evaluate the risk of recurrence possibly caused by preoperative bronchoscopic cancer confirmation in stage1A non-small cell lung cancer.

METHODS

One hundred and seventy-nine cases of peripheral non-small cell lung cancer (including 151 adenocarcinoma) with no more than 3 cm in their tumor longer diameter were selected. All patients underwent preoperative diagnostic bronchoscopy followed by lobectomy, and were demonstrated to have pathologically free of lymph node involvement and pleural involvement. Radiological and pathological low-grade adenocarcinomas were excluded. Of 179 cases, 95 were confirmed lung cancer by bronchoscope (Group 1) and rest 84 had failed cancer confirmation by bronchoscope before surgery (Group 2). Forty-eight pairs for non-small cell lung cancer and 41 pairs for adenocarcinoma were identified from each group by propensity caliper matching. Kaplan-Meier method and log-rank test were performed on matched groups, and Cox proportional hazard model analysis was performed on whole matched cases.

RESULTS

Log-rank test revealed no significant inferiority of recurrence-free survival of Group 1 in both all-NSCLC and adenocarcinoma subset. Cox proportional hazard model analysis also revealed that the 'presence of preoperative bronchoscopic cancer confirmation' dose not increase risk of recurrence in both NSCLC and adenocarcinoma subset.

CONCLUSIONS

It is unlikely that preoperative bronchoscopic cancer confirmation would increase recurrence risk in stage1A non-small cell lung cancer; however, a future prospective study with larger cohorts would be warranted to validate the results.

A Prospective Study of Loose Tissue Fragments in Non-Small Cell Lung Cancer Resection Specimens: An Alternative View to "Spread Through Air Spaces"

The World Health Organization Classification of Lung Tumors considers "Spread Through Air Spaces" a form of invasion in lung adenocarcinoma. The recently described spread of free-floating cell clusters during lung specimen sectioning, otherwise known as "Spread Through A Knife Surface," represents an ex vivo artifact. The purpose of this study was to prospectively investigate the presence and frequency of these free-floating tumor cell clusters in surgically resected lung cancer specimens and their possible relation to gross examination procedures. A prospective, multi-institutional study of non-small cell lung cancer resection specimen was undertaken. At prosection the first cut was made with a clean knife; the second cut was made in a parallel plane to the first. Four tissue blocks were taken from upper and lower parts of first and second cuts. Hematoxylin and eosin-stained slides were examined for displaced benign and/or malignant tissue fragments. Forty-four resection specimens were studied. The mean number of tumor clusters for blocks 1 to 4 was 0.36, 1.44, 1.86, and 1.95, respectively, and for benign fragments was 0.11, 0.11, 0.13, and 0.25, respectively. Almost all cell clusters were intra-alveolar. Comparison of tumor cell clusters in block 1 with blocks 2 to 4 was significant with P-values (Friedman test for repeated measures 0.03) 0.031, 0.02, and 0.05, respectively. Overall 93% of the loose tissue fragments could be explained by mechanical forces associated with tissue handling. While the 2015 World Health Organization Classification of Lung Tumors recognizes Spread Through Air Spaces as a form of lung cancer invasion, such is debatable and in many instances likely represents mechanical artifact, including dissemination along the prosecting knife blade.

A comparative analysis of dual-phase dual-energy CT and FDG-PET/CT for the prediction of histopathological invasiveness of non-small cell lung cancer

PURPOSE

To compare dual-phase dual-energy CT (DE-CT) with FDG-PET/CT for predicting histopathological locoregional invasiveness of non-small cell lung cancers (NSCLCs).

MATERIALS AND METHODS

We selected 63 consecutive patients with NSCLC lesions (37 males, 26 females; age range, 44-85 years; mean age, 69 years) who were evaluated preoperatively by both DE-CT and PET/CT at our institution. Postoperative microscopic invasiveness (lymphatic permeation, vascular invasion, and/or pleural involvement) was reviewed, and we defined locoregionally invasive tumors as those that had at least one positive finding of microscopic invasiveness. DE-CT scanning in the arterial and delayed phases was performed after injection of iodinated contrast media using 140-kVp and 80-kVp tube voltages. Three-dimensional iodine-related attenuation of primary tumors in the arterial and delayed phases was quantified automatically using "syngo Dual Energy Lung Nodules" application software, and the ratio of arterial phase to delayed phase enhancement (A/D ratio) was calculated. The A/D ratio and SUVmax on PET/CT were evaluated with respect to postoperative invasiveness by univariate logistic regression analysis.

RESULTS

The A/D ratio was significantly correlated with lymphatic permeation, vascular invasion, and pleural involvement (p=0.011, p=0.021, and p=0.010, respectively). In contrast, the SUVmax was significantly correlated with pleural involvement (p=0.020) but not with lymphatic permeation or vascular invasion (p=0.088 and p=0.100, respectively). In the subgroup of patients with lesion diameters ≤2cm, the A/D ratio was significantly correlated with locoregional invasiveness (p=0.040), while the SUVmax was not (p=0.121).

CONCLUSION

For the prediction of microscopic invasiveness of NSCLCs, the diagnostic performance of dual-phase DE-CT may be comparable to that of FDG-PET/CT.