Limited resection for noninvasive bronchioloalveolar carcinoma diagnosed by intraoperative pathologic examination

Limited resection is comparable to lobectomy for tumor size ≤ 2 cm pulmonary invasive mucinous adenocarcinoma

OBJECTIVES

Invasive mucinous adenocarcinoma (IMA) has a rare incidence with better prognosis than nonmucinous adenocarcinoma. We aimed to investigate the prognosis between limited resection and lobectomy for patients with clinical stage IA IMA ≤ 2 cm.

METHODS

Data were taken from two cohorts: In Shanghai Pulmonary Hospital (SPH) corhort, we identified 403 patients with clinical stage IA IMA who underwent surgery. In the SEER corhort, 480 patients with stage T1 IMA who after surgery were included. Recurrence-free survival (RFS) for SPH corhort, lung cancer-specific survival (LCSS) for the SEER corhort and overall survival (OS) for both corhort were compared between patients undergoing lobectomy and limited resection by Log-rank and Cox proportional hazard regression model.

RESULTS

In SPH corhort, patients who underwent limited resection had equivalent prognosis than those underwent lobectomy (5-year RFS: 79.3% versus. 82.6%, p = 0.116; 5-year OS: 86.2% versus. 88.3%, p = 0.235). However, patients with IMA > 2 to 3 cm had worse prognosis than those with IMA ≤ 2 cm (5-year RFS: 73.7% versus. 86.1%, p = 0.007). In the analysis of IMA > 2 to 3 cm subgroup, multivariate analysis showed that limited resection was an independent risk factor of RFS (hazard ratio, 2.417; 95% confidence interval, 1.157-5.049; p = 0.019), while OS (p = 0.122) was not significantly different between two groups. For IMA ≤ 2 cm, limited resection was not a risk factor of RFS (p = 0. 953) and OS (p = 0.552). In the SEER corhort, IMA ≤ 2 cm subgroup, limited resection was equivalent prognosis in LCSS (p = 0.703) and OS (p = 0.830).

CONCLUSIONS

Limited resection could be a potential surgical option which comparable to lobectomy in patients with clinical stage IA IMA ≤ 2 cm.

Construction and validation of a predictive model of invasive adenocarcinoma in pure ground-glass nodules less than 2 cm in diameter

OBJECTIVES

In this study, we aimed to develop a multiparameter prediction model to improve the diagnostic accuracy of invasive adenocarcinoma in pulmonary pure glass nodules.

METHOD

We included patients with pulmonary pure glass nodules who underwent lung resection and had a clear pathology between January 2020 and January 2022 at the Qilu Hospital of Shandong University. We collected data on the clinical characteristics of the patients as well as their preoperative biomarker results and computed tomography features. Thereafter, we performed univariate and multivariate logistic regression analyses to identify independent risk factors, which were then used to develop a prediction model and nomogram. We then evaluated the recognition ability of the model via receiver operating characteristic (ROC) curve analysis and assessed its calibration ability using the Hosmer-Lemeshow test and calibration curves. Further, to assess the clinical utility of the nomogram, we performed decision curve analysis.

RESULT

We included 563 patients, comprising 174 and 389 cases of invasive and non-invasive adenocarcinoma, respectively, and identified seven independent risk factors, namely, maximum tumor diameter, age, serum amyloid level, pleural effusion sign, bronchial sign, tumor location, and lobulation. The area under the ROC curve was 0.839 (95% CI: 0.798-0.879) for the training cohort and 0.782 (95% CI: 0.706-0.858) for the validation cohort, indicating a relatively high predictive accuracy for the nomogram. Calibration curves for the prediction model also showed good calibration for both cohorts, and decision curve analysis showed that the clinical prediction model has clinical utility.

CONCLUSION

The novel nomogram thus constructed for identifying invasive adenocarcinoma in patients with isolated pulmonary pure glass nodules exhibited excellent discriminatory power, calibration capacity, and clinical utility.

Clinical and radiomic factors for predicting invasiveness in pulmonary ground‑glass opacity

Patients with preinvasive or invasive pulmonary ground-glass opacity (GGO) often face different clinical treatments and prognoses. The present study aimed to identify the invasiveness of pulmonary GGO by analysing clinical and radiomic features. Patients with pulmonary GGOs who were treated between January 2014 and February 2019 were included. Clinical features were collected, while radiomic features were extracted from computed tomography records using the three-dimensional Slicer software. Predictors of GGO invasiveness were selected by least absolute shrinkage and selection operator logistic regression analysis, and receiver operating characteristic (ROC) curves were drawn for each prediction model. A total of 194 patients with pulmonary GGOs were included in the present study. The maximum diameter of the solid component, waveletHLL_ngtdm_Coarseness (P=0.03), waveletLHH_firstorder_Maximum (P<0.01) and waveletLLH_glrlm_LongRunEmphasis (P<0.01) were significant predictors of invasive lung GGOs. The area under the ROC curve (AUC) for the prediction models of clinical features and radiomic features was 0.755 and 0.719, respectively, whereas the AUC for the combined prediction model was 0.864 (95% CI, 0.802-0.926). Finally, a nomogram was established for individualized prediction of invasiveness. The combination of radiomic and clinical features can enable the differentiation between preinvasive and invasive GGOs. The present results can provide some basis for the best choice of treatment in patients with lung GGOs.

Sublobectomy for stage IA1-2 invasive lung adenocarcinoma with consolidation tumor ratio ≤ 0.25

BACKGROUND

Sublobectomy for early-stage non-small cell lung cancer (NSCLC) remains a matter of debate. This study aimed to discuss the feasibility of sublobectomy in patients with pathological-stage IA1-2 confirmed as pathologically invasive but radiologically noninvasive adenocarcinoma.

METHODS

From 2011 to 2019, we screened clinical stage IA1-IA2 lung cancer patients who underwent surgery at the Guangdong Provincial People's Hospital (GDPH). Inclusion criteria were maximum tumor diameter of 2.0 cm or less, consolidation tumor ratio (CTR) ≤ 0.25, and pathologically confirmed invasive adenocarcinoma. Sublobectomy (segmentectomy and wedge resection) and lobectomy groups were created, and propensity scores were computed. The primary endpoints were lung cancer-specific overall survival (LCSS) and LCS- relapse-free survival (LCS-RFS) after adjusting propensity scores.

RESULTS

A total of 1731 patients were screened, and 100 patients were enrolled. The lobectomy group had 51 patients and the limited resection group had 49. No cases relapsed, and two patients died from nontumor causes. For the entire cohort, the 5-year LCSS and 5-year LCS-RFS were 100% in the lobectomy and limited resection groups. When propensity scores matched, there were no differences in LCSS and LCS-RFS between the two groups (LCSS:100%, LCS-RFS 100% in lobectomy and limited resection, respectively).

DISCUSSION

Sublobectomy may be curative for pathologically invasive but radiologically noninvasive adenocarcinoma at pathological stage IA1-2.

Could concurrent biopsy and microwave ablation be reliable? Concordance between frozen section examination and final pathology in CT-guided biopsy of lung cancer

PURPOSE

Microwave ablation combined with concurrent biopsy has been used for lung cancer. Frozen section (FS) diagnosis is an important supplement for the final pathology (FP). Thus, a retrospective study was conducted to evaluate the concordance between FS examination and FP in the computed tomography (CT)-guided biopsy of lung cancer.

MATERIALS AND METHODS

Patients who underwent percutaneous transthoracic needle lung biopsies and were diagnosed using both intraoperative FS examination and FP were retrospectively enrolled. Concordance between FS findings and FP in the diagnosis of malignant lung cancer and the definitive histology types were recorded.

RESULTS

Overall, 163 patients were enrolled. The concordance rate in the diagnosis of malignant tumors was 96.3%. The definitive histology types were concordant between FS examinations and FP in 112 patients (68.7%). Lung cancers undefined with FS but diagnosed as adenocarcinoma with FP were the most common type, observed in 18 patients. The concordance in the histology type was lower for those requiring immunohistochemistry for FP diagnoses (47.3 vs. 79.6%, p < 0.000). Concordance rates differed for the different histology types diagnosed using FP (adenocarcinoma vs. squamous cell carcinoma vs. small-cell lung cancer vs. others, 76.6 vs. 56.2 vs. 69.2 vs. 0.0%, p < 0.000).

CONCLUSIONS

FS was inferior to FP in the diagnosis of definitive histology types, but had a high concordance with FP in the diagnosis of malignant lung cancer.

Differentiation of adenocarcinoma in situ with alveolar collapse from minimally invasive adenocarcinoma or invasive adenocarcinoma appearing as part-solid ground-glass nodules (≤ 2 cm) using computed tomography

PURPOSE

To investigate the differentiating computed tomographic (CT) features between adenocarcinoma in situ (AIS) with alveolar collapse and minimally invasive adenocarcinoma (MIA) or invasive adenocarcinoma (IA) appearing as part-solid nodules.

METHODS

A total of 147 consecutive patients with 157 pathology-confirmed part-solid ground-glass nodules (GGNs) ≤ 20 mm without other pathological condition such as inflammation and fibrosis who underwent chest CT were included.

RESULTS

The 157 part-solid GGNs included 33 (21.02%) pathologically confirmed AISs with alveolar collapse. Multivariate analysis revealed that smaller lesion size (odds ratio [OR] 0.671), and well-defined border (OR 5.544), concentrated distribution (OR 7.994), and homogeneity of the solid portion (OR 4.365) were significant independent predictors for differentiating AIS with alveolar collapse from MIA (P < 0.05) with excellent accuracy (area under receiver operating characteristic [ROC] curve, 0.902). Multivariate analysis revealed that smaller lesion size (OR 0.782), and size (OR 0.821), well-defined border (OR 5.752), and homogeneity of solid portion (OR 6.182) were significant independent predictors differentiating AIS with alveolar collapse from IA (P < 0.05) with excellent accuracy (area under ROC curve 0.910).

CONCLUSION

Among part-solid GGNs, AIS with alveolar collapse can be accurately differentiated from MIA on the basis of smaller lesion size, well-defined border, concentrated distribution, and homogeneity of solid portion, and from IA according to smaller lesion size, and smaller size, well-defined border, and homogeneity of solid portion.

Surgical choice for patients with stage I non-small-cell lung cancer ≤2 cm: an analysis from surveillance, epidemiology, and end results database

Background

No consensus was reached on the surgical procedure for patients with stage I non-small-cell lung cancer (NSCLC) ≤ 2 cm. The aim of this study is to investigate the appropriate surgical procedure for stage I NSCLC ≤2 cm.

Methods

Patients with stage I NSCLC ≤2 cm received wedge resection, segmentectomy, lobectomy between January 2004 and December 2015 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. Data were stratified by age, gender, race, side, location, grade, histology, extent of lymphadenectomy. Overall survival (OS) and lung cancer-specific survival (LCSS) were compared among patients received wedge resection, segmentectomy, lobectomy. Univariate analysis and multivariable Cox regression were performed to identify the prognostic factors of OS and LCSS.

Results

A total of 16,511 patients with stage I NSCLC ≤2 cm were included in this study, of whom 2945 patients were classified as stage I NSCLC ≤1 cm. Lobectomy had better OS and LCSS when compared with wedge resection in patients with NSCLC ≤2 cm. Only OS favored lobectomy compared with segmentectomy in stage I NSCLC>1 to 2 cm. Multivariable analysis showed that segmentectomy had similar OS and LCSS compared with lobectomy in patients with stage I NSCLC ≤2 cm. Lymph node dissection (LND) was associated with better OS in patients with NSCLC ≤2 cm and better LCSS in patients with stage I NSCLC>1 to 2 cm.

Conclusions

Segmentectomy showed comparable survival compared with lobectomy in patients with stage I NSCLC ≤2 cm. LND can provide more accurate pathological stage, may affect survival, and should be recommended for above patients.

Clock dial integrated positioning combined with single utility port video-assisted thoracoscopic surgery: a new localization method for lung tumors

Background

Preoperative localization of lung tumor mainly consisted of two methods: CT-guided percutaneous localization and electromagnetic navigation bronchoscopy-guided localization. However, these invasive methods could result in serious complications. In order to avoid the adverse effects of preoperative invasive localization, we propose a method of intraoperative noninvasive localization for lung tumors: clock dial integrated positioning (CDIP).

Methods

To retrospectively analyze the clinic data about the application of CDIP for 127 lung tumour patients in single utility port video-assisted thoracoscopic surgery (SUPVATS) between June 2017 and October 2017.

Results

One hundred and twenty-four cases (97.64%) underwent thoracoscopic surgery, which including 14 lobectomy, 107 partial resection, 2 lobectomy plus partial resection and 1 left pneumonectomy. Three cases (2.36%) underwent thoracoscopic biopsy. The mean operation time and intraoperative bleeding were 47.9±22.1 min and 70.1±40.3 mL, respectively. The mean postoperative hospital stay and chest drain duration were 3.9±2.2 and 3.6±1.8 days, respectively. There were 118 cases of malignant tumors, including adenocarcinoma (n=101), squamous cell carcinoma (n=9), large cell carcinoma (n=2), small cell lung carcinoma (n=3), and metastatic lung carcinoma (n=3). The remaining nine cases were benign tumors, including granuloma (n=3), intrapulmonary lymph node (n=2), sclerosing hemangioma (n=2), and hamartoma (n=2). The incidence of postoperative complications was 10.2%. There was no mortality, secondary operation, or conversion to open procedure due to massive intraoperative bleeding.

Conclusions

CDIP combined with SUPVATS is a safe, feasible, and effective method for the localization of lung tumors. This novel method can provide a reliable alternative technique when the marker is dislocated.

A single-arm study of sublobar resection for ground-glass opacity dominant peripheral lung cancer

BACKGROUND

The optimal mode of surgery for ground-glass opacity dominant peripheral lung cancer defined with thoracic thin-section computed tomography remains unknown.

METHODS

We conducted a single-arm confirmatory trial to evaluate the efficacy and safety of sublobar resection for ground-glass opacity dominant peripheral lung cancer. Lung cancer with maximum tumor diameter 2.0 cm or less and with consolidation tumor ratio 0.25 or less based on thin-section computed tomography were registered. The primary end point was 5-year relapse-free survival. The planned sample size was 330 with the expected 5-year relapse-free survival of 98%, threshold of 95%, 1-sided α of 5%, and power of 90%. The trial is registered with University Hospital Medical Information Network Clinical Trials Registry, number University Hospital Medical Information Network 000002008.

RESULTS

Between May 2009 and April 2011, 333 patients were enrolled from 51 institutions. Median age was 62 years (interquartile range, 56-68), and 109 were smokers. Median maximum tumor diameter was 1.20 cm (1.00-1.54). Median maximum tumor diameter of consolidation was 0 (0.00-0.20). The primary end point, 5-year relapse-free survival, was estimated on 314 patients who underwent sublobar resection. Operative modes were 258 wide wedge resections and 56 segmentectomies. Median pathological surgical margin was 15 mm (0-55). The 5-year relapse-free survival was 99.7% (90% confidence interval, 98.3-99.9), which met the primary end point. There was no local relapse. Grade 3 or higher postoperative complications based on Common Terminology Criteria for Adverse Effect v3.0 were observed in 17 patients (5.4%), without any grade 4 or 5.

CONCLUSIONS

Sublobar resection with enough surgical margin offered sufficient local control and relapse-free survival for lung cancer clinically resectable N0 staged by computed tomography with 3 or fewer peripheral lesions 2.0 cm or less amenable to sublobar resection and with a consolidation tumor ratio of 0.25 or less.

Oncologic Outcomes of Surgery Versus SBRT for Non-Small-Cell Lung Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

The optimal treatment of stage I non-small-cell lung carcinoma is subject to debate. The aim of this study was to compare overall survival and oncologic outcomes of lobar resection (LR), sublobar resection (SR), and stereotactic body radiotherapy (SBRT).

METHODS

A systematic review and meta-analysis of oncologic outcomes of propensity matched comparative and noncomparative cohort studies was performed. Outcomes of interest were overall survival and disease-free survival. The inverse variance method and the random-effects method for meta-analysis were utilized to assess the pooled estimates.

RESULTS

A total of 100 studies with patients treated for clinical stage I non-small-cell lung carcinoma were included. Long-term overall and disease-free survival after LR was superior over SBRT in all comparisons, and for most comparisons, SR was superior to SBRT. Noncomparative studies showed superior long-term overall and disease-free survival for both LR and SR over SBRT. Although the papers were heterogeneous and of low quality, results remained essentially the same throughout a large number of stratifications and sensitivity analyses.

CONCLUSION

Results of this systematic review and meta-analysis showed that LR has superior outcomes compared to SBRT for cI non-small-cell lung carcinoma. New trials are underway evaluating long-term results of SBRT in potentially operable patients.

Two nomograms based on CT features to predict tumor invasiveness of pulmonary adenocarcinoma and growth in pure GGN: a retrospective analysis

PURPOSE

The aim of the study is to construct two nomograms for predicting the invasive extent of pulmonary adenocarcinoma and nodule growth in patients with pulmonary pure ground-glass nodules (pGGN).

METHOD

Consecutive patients with pGGNs (n = 172) were retrospectively studied at one institution, formed the development cohort in predicting IPAs' nomogram. A separate cohort of patients with pGGNs (n = 116) from another institution was used for validation. For the predicting growth nomogram, the primary cohort of patients with pGGNs (n = 80) was from the former institution. We developed the nomogram for predicting IPA using binary logistic regression model, and a Cox multivariable model for the growth nomogram. We assessed nomogram model performance by calibration and discrimination (C-index).

RESULTS

The variables selected in binary logistic regression model (lesion size and shape) had a significant effect on identifying IPA from preinvasive lesion. The C-index of the development and validation cohort were 0.819 (95% CI 0.753-0.874) and 0.811 (95% CI 0.728-0.878), respectively. The risk variables (lesion size, blood vessel types) were selected in the multivariable Cox model. The C-index was 0.880 in the development cohort.

CONCLUSION

Our nomograms are reliable prognostic methods that can predict the invasiveness of pulmonary adenocarcinomas and the growth of pure GGN in preoperative.

Three-dimensional mean CT attenuation value of pure and part-solid ground-glass lung nodules may predict invasiveness in early adenocarcinoma

AIM

This study evaluated the relationship between three-dimensional (3D) mean computed tomography (CT) attenuation values of ground-glass nodules (GGN) and pathological invasiveness in early lung adenocarcinoma. The diagnostic accuracy of 3D CT attenuation values was compared with that of two-dimensional (2D) CT attenuation values and standardised uptake value on positron-emission tomography (PET).

MATERIALS AND METHODS

Surgical and radiological data from 96 pure or part-solid GGNs of <20 mm were analysed retrospectively. Mean 2D and 3D CT attenuation values of the tumours were obtained with semi-automated volumetric software. Pathological invasiveness was diagnosed according to the International Association for the Study of Lung Cancer (IASLC))/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification. Pre-invasive lesions and minimally invasive adenocarcinomas were classified as non-invasive adenocarcinoma. Univariate and multivariate analyses determined relationships between pathological invasiveness and clinical/radiological findings. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cut-off value for detecting invasive adenocarcinoma.

RESULTS

A total of 66 non-invasive and 30 invasive adenocarcinoma cases between 2010 and 2016 were analysed. Univariate analysis revealed four tumour invasiveness-associated predictors: maximum diameter, SUVmax, mean 2D CT attenuation value, and mean 3D CT attenuation value (p<0.05). Multivariate analysis revealed that the maximum diameter, SUVmax, and mean 3D CT attenuation value were significant predictors of pathological invasiveness (p=0.023, 0.022, 0.004). The area under the ROC curve to predict invasive adenocarcinoma for mean 3D CT attenuation value was 0.838 and the cut-off value was -489 HU.

CONCLUSION

The mean 3D CT attenuation value could distinguish pre-invasive lesions and minimally invasive adenocarcinoma from invasive adenocarcinoma.

A prospective 5-year follow-up study after limited resection for lung cancer with ground-glass opacity

OBJECTIVES

The incidence of small-sized pulmonary adenocarcinomas with ground-glass opacity (GGO) has recently increased, with excellent postoperative prognosis. The limited resection of such cancers has been deemed to be acceptable based on retrospective studies. We conducted a prospective multi-institutional study evaluating the validity of limited resection for small-sized pulmonary adenocarcinoma with GGO.

METHODS

The inclusion criteria were 25-80 years of age, no prior treatment, a maximum tumour diameter of 8-20 mm, a GGO ratio of ≥ 80%, clinical T1N0M0, lower 18F-fluorodeoxyglucose accumulation than the mediastinum, resectable by sublobar resection, pulmonary lobectomy tolerable and an intraoperative pathological diagnosis of bronchiloalveolar carcinoma. Wedge resection was preferred, but segmentectomy was permitted. Disease-specific survival and overall survival were analysed.

RESULTS

From November 2006 to April 2012, 73 patients were enrolled from 13 institutions. One patient was ineligible, and the remaining 72 patients were preregistered. The tumours of 3 and 14 patients were intraoperatively diagnosed as benign lesions and adenocarcinomas with mixed subtype, respectively. Intraoperative cytological/histological examination of surgical margin was not performed in 2 patients, and the remaining 53 patients were ultimately eligible for this study. The mean tumour size was 14.0 mm and the mean GGO ratio was 95.9%. Thirty-nine and 14 patients underwent wedge resection and segmentectomy, respectively. Although all tumours were intraoperatively diagnosed as bronchioloalveolar carcinomas, 6 were ultimately diagnosed as adenocarcinoma with a mixed subtype. No completion lobectomy was performed. As of 1 May 2017, no recurrence of the original lung cancer was observed during 60.0-126.3 months after surgery. Two patients died from other diseases. The 5-year disease-specific and overall survival rates were 100% and 98.1%, respectively. The reduction in the pulmonary function after limited resection was minimal.

CONCLUSIONS

With these criteria, limited resection was performed safely without any recurrence, and the postoperative pulmonary function was well preserved. The outcomes of limited resection for small-sized lung cancer with GGOs that met the criteria of this study were satisfactory.

Prognostic factors for stage I lung adenocarcinoma and surgical management of subsolid nodules

Background

This study aims to identify the prognostic factors for stage I lung adenocarcinoma and to evaluate the surgical management of subsolid nodules.

Methods

The study included 133 patients (90 males, 43 females; mean age 64.9 years; range, 29 to 82 years) who had undergone operation in our clinic for stage I lung adenocarcinoma between January 2007 and December 2015. Clinical, radiological and pathological data were retrospectively evaluated and their effects on recurrence and survival were examined by Kaplan-Meier and Cox regression analyses.

Results

Comparing the histopathological tumor types according to the pathological tumors size, we determined that the prevalence of invasive adenocarcinoma significantly increased with increasing tumor size (p<0.001). For all nodules, a tumor disappearance rate lower than 25% negatively influenced disease-free survival and a maximum standardized uptake value higher than 5.6 negatively influenced overall survival (p=0.027 for both). The grouping, which was performed considering the maximum standardized uptake value 5.6 as the cut-off value, was an independent prognostic factor for overall survival (hazard ratio: 5.973, 95% confidence interval: 1.186-30.073, p=0.03). Five-year overall survival rate was statistically significantly higher in patients who underwent wedge resection or segmentectomy for subsolid nodules compared to those who underwent lobectomy (100% vs. 79.3%, p=0.044).

Conclusion

Sublobar resections can be safely performed in subsolid nodules smaller than 2 cm in diameter with tumor disappearance rate ≥25% and maximum standardized uptake value ≤5.6.

Assessing the inter-observer variability of Computer-Aided Nodule Assessment and Risk Yield (CANARY) to characterize lung adenocarcinomas

Lung adenocarcinoma (ADC), the most common lung cancer type, is recognized increasingly as a disease spectrum. To guide individualized patient care, a non-invasive means of distinguishing indolent from aggressive ADC subtypes is needed urgently. Computer-Aided Nodule Assessment and Risk Yield (CANARY) is a novel computed tomography (CT) tool that characterizes early ADCs by detecting nine distinct CT voxel classes, representing a spectrum of lepidic to invasive growth, within an ADC. CANARY characterization has been shown to correlate with ADC histology and patient outcomes. This study evaluated the inter-observer variability of CANARY analysis. Three novice observers segmented and analyzed independently 95 biopsy-confirmed lung ADCs from Vanderbilt University Medical Center/Nashville Veterans Administration Tennessee Valley Healthcare system (VUMC/TVHS) and the Mayo Clinic (Mayo). Inter-observer variability was measured using intra-class correlation coefficient (ICC). The average ICC for all CANARY classes was 0.828 (95% CI 0.76, 0.895) for the VUMC/TVHS cohort, and 0.852 (95% CI 0.804, 0.901) for the Mayo cohort. The most invasive voxel classes had the highest ICC values. To determine whether nodule size influenced inter-observer variability, an additional cohort of 49 sub-centimeter nodules from Mayo were also segmented by three observers, with similar ICC results. Our study demonstrates that CANARY ADC classification between novice CANARY users has an acceptably low degree of variability, and supports the further development of CANARY for clinical application.

Three-dimensional (3D)- computed tomography bronchography and angiography combined with 3D-video-assisted thoracic surgery (VATS) versus conventional 2D-VATS anatomic pulmonary segmentectomy for the treatment of non-small cell lung cancer

Background

Compared to the pulmonary lobe, the anatomical structure of the pulmonary segment is relatively complex and prone to variation, thus the risk and difficulty of segmentectomy is increased. We compared three‐dimensional computed tomography bronchography and angiography (3D‐CTBA) combined with 3D video‐assisted thoracic surgery (3D‐VATS) to perform segmentectomy to conventional two‐dimensional (2D)‐VATS for the treatment of non‐small cell lung cancer (NSCLC).

Methods

We retrospectively reviewed the data of randomly selected patients who underwent 3D‐CTBA combined with 3D‐VATS (3D‐CTBA‐VATS) or 2D‐VATS at the Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University Hospital, from January 2014 to May 2017.

Results

The operative duration of 3D group was significantly shorter than the 2D group (P < 0.05). There was no significant difference in the number of dissected lymph nodes between the two groups (P > 0.05). The extent of intraoperative bleeding and postoperative drainage in the 3D group was significantly lower than in the 2D group (P < 0.05). Chest tube duration in the 3D group was shorter than in the 2D group (P < 0.05). Incidences of pulmonary infection, atelectasis, and arrhythmia were not statistically different between the two groups (P > 0.05). However, hemoptysis and pulmonary air leakage (>3d) occurred significantly less frequently in the 3D than in the 2D group (P < 0.05).

Conclusion

3D‐CTBA‐VATS is a more accurate and smooth technique and leads to reduced intraoperative and postoperative complications.

[Combining 3D-CTBA and 3D-VATS Single-Operation-Hole to Anatomical Segmentectomy in the Treatment of Non-small Cell Lung Cancer]

背景与目的

中国是肺癌高发地区，其发病率及死亡率在恶性肿瘤中均占首位。目前低剂量CT检查的普及使早期肺癌检出率显著提高，解剖性肺段切除目前广泛应用于Ia期非小细胞肺癌（non-small cell lung cancer, NSCLC）及不能耐受肺叶切除肺癌患者。但因肺段解剖结构及手术操作相对复杂，使得其具有较高的手术风险与难度。我们应用三维计算机断层扫描支气管血管成像（three-dimensional computed tomography bronchography and angiography, 3D-CTBA）及三维电视辅助胸部外科技术（three-dimensional video-assisted thoracic surgery, 3D-VATS）单操作孔行解剖性肺段切除微创手术技术治疗NSCLC，以探讨其临床效果，为其临床应用提供相关可行性及理论依据。

方法

回顾性分析苏州大学附属第一人民医院胸外科2015年10月-2017年04月共施行57例术前对肺部病灶予以3D-CTBA重建以及术中应用3D-VATS单操作孔进行解剖性肺段切除治疗NSCLC病例。

结果

全组均全腔镜下顺利完成，无中转开胸。手术时间平均（142.2±28.3）min，术中出血量平均（93.8±46.5）mL。平均淋巴结清扫数目（9.1±2.2）个，术后胸腔引流量平均（429.8±181.2）mL。术后留置胸管时间（2.8±1.1）d。平均住院时间（5.2±1.3）d。术后病理示良性病变9例，约占15.7%，恶性病变48例，约占84.2%。术后并发症：肺部感染3例（5.2%），肺不张1例（1.7%），少量咯血1例（1.7%），肺漏气2例（> 3 d, 3.5%），心律失常4例（7.0%）。术后平均随访10个月，无支气管胸膜瘘、乳糜胸、包裹性胸腔积液等并发症，随访患者中无复发及远处转移病例。

结论

应用3D-CTBA及3D-VATS单操作孔行解剖性肺段切除治疗NSCLC的安全有效，适用于早期NSCLC以及不能耐受肺叶切除患者。

Survival and risk factors for progression after resection of the dominant tumor in multifocal, lepidic-type pulmonary adenocarcinoma

BACKGROUND

It remains unclear whether a dominant lung adenocarcinoma that presents with multifocal ground glass opacities (GGOs) should be treated by local therapy. We sought to address survival in this setting and to identify risk factors for progression of unresected GGOs.

METHODS

Retrospective review of 70 patients who underwent resection of a pN0, lepidic adenocarcinoma, who harbored at least 1 additional GGO. Features associated with GGO progression were determined using logistic regression and survival was evaluated using the Kaplan-Meier method.

RESULTS

Subjects harbored 1 to 7 GGOs beyond their dominant tumor (DT). Mean follow-up was 4.1 ± 2.8 years. At least 1 GGO progressed after DT resection in 21 patients (30%). In 11 patients (15.7%), this progression prompted resection (n = 5) or stereotactic radiotherapy (n = 6) at mean 2.8 ± 2.3 years. Several measures of the overall tumor burden were associated with GGO progression (all P values < .03) and with progression prompting intervention (all P values < .01). In logistic regression, greater DT size (odds ratio, 1.07; 95% confidence interval, 1.01-1.14) and an initial GGO > 1 cm (odds ratio, 4.98; 95% confidence interval, 1.15-21.28) were the only factors independently associated with GGO progression. Survival was not negatively influenced by GGO progression (100% with vs 80.7% without; P = .1) or by progression-prompting intervention (P = .4).

CONCLUSIONS

At 4.1-year mean follow-up, 15.7% of patients with unresected GGOs after resection of a pN0 DT underwent subsequent intervention for a progressing GGO. Some features correlated with GGO growth, but neither growth, nor need for an intervention, negatively influenced survival. Thus, even those at highest risk for GGO progression should not be denied resection of a DT.

Preoperative nomogram for identifying invasive pulmonary adenocarcinoma in patients with pure ground-glass nodule: A multi-institutional study

PURPOSE

To construct a preoperative nomogram to differentiate invasive pulmonary adenocarcinomas (IPAs) from preinvasive lesions in patients with solitary pure ground-glass nodules (GGN).

METHODS

A primary cohort of patients with pathologically confirmed pulmonary solitary pure GGN after surgery were retrospectively studied at five institutions from January 2009 to September 2015. Half of the patients were randomly selected and assigned to a model-development cohort, and the remaining patients were assigned to a validation cohort. A nomogram predicting the invasive extent of the solitary GGNs was constructed based on the independent risk factors. Predictive performance was evaluated by concordance index (C-index) and calibration curve.

RESULTS

Out of 898 cases included in the study, 501 (55.8%) were preinvasive lesions and 397 (44.2%) were IPAs. In the univariate analysis, lesion size (p < 0.001), lesion margin (p = 0.041), lesion shape (p < 0.001), mean computed tomography (CT) value (p = 0.018), presence of pleural indentation (p = 0.017), and smoking status (p = 0.014) were significantly associated with invasive extent. In multivariate analysis, lesion size (p < 0.001), lesion margin (p = 0.042), lesion shape (p < 0.001), mean CT value (p = 0.014), presence of pleural indentation (p = 0.026), and smoking status (p = 0.004) remained the predictive factors of invasive extent. A nomogram was developed and validation results showed a C-index of 0.94, demonstrating excellent concordance between predicted and observed results.

CONCLUSIONS

We established and validated a novel nomogram that can identify IPAs from preinvasive lesions in patients with solitary pure GGN.

Evaluation of grading systems in stage I lung adenocarcinomas: a retrospective cohort study

AIMS

There is no internationally accepted grading system for lung adenocarcinoma despite the new WHO classification. The architectural grade, the Kadota grade and the Sica score were evaluated and compared with overall (OS) and disease-free survival (DFS).

METHODS

Comprehensive histological subtyping was used in a series of resected stage I lung adenocarcinoma to identify subtypes of adenocarcinomas, the architectural grade, the Kadota grade, the Sica grade, the mitotic count, nuclear atypia, the presence of lymphovascular, vascular and airway propagation, necrosis, and micropapillary or solid growth pattern in any percentage. Statistical models fitted included Kaplan-Meier estimates and Cox proportional hazard regression models.

RESULTS

261 stage I adenocarcinomas were included. The 5-year survivals of different subtypes were as follows: lepidic (n=40, OS: 92.5%; DFS 91.6%), acinar (n=54, OS: 81.8%; DFS: 68.6%), papillary (n=49, OS: 73.6%; DFS: 61.0%), solid (n=95, OS: 64.7%; DFS: 57.8%) and micropapillary (n=23, OS: 34.8%; DFS: 33.5%). Concerning the architectural grade, there were significant differences between OS and DFS of low and intermediate (pOS=0.005, pDFS<0.001), low and high (pOS<0.001, pDFS<0.001) and intermediate and high grades (pOS=0.002, pDFS<0.001). Low-grade and intermediate grade tumours did not differ in survival according to Kadota grade and Sica grade. In the multivariable model, architectural grade was found to be an independent prognostic marker. In another model, architectural pattern proved to be superior to architectural grade.

CONCLUSIONS

Of the three grading systems compared, the architectural grade makes the best distinction between the outcome of low-grade, intermediate-grade and high-grade stage I adenocarcinomas.

Stereotactic body radiotherapy for operable early-stage non-small cell lung cancer

PURPOSE

To analyze outcomes of stereotactic body radiotherapy (SBRT) for operable patients with early-stage non-small cell lung cancer (NSCLC) and to evaluate factors associated with outcomes.

METHODS

We retrospectively analyzed operable patients with NSCLC, staged as cT1-2N0M0, treated with SBRT between 2006 and 2015. Both biopsy-proven and clinically diagnosed NSCLC were included. Local control and survival rates were calculated and compared between subsets of patients. We investigated factors associated with outcomes.

RESULTS

We identified 88 operable patients among 661 patients with cT1-2N0M0 NSCLC. The median age was 79 years (range: 55-88). The median follow-up time after SBRT was 40 months (range: 4-121). Fifty-nine patients had been pathologically diagnosed and the other 29 had been clinically diagnosed as having NSCLC. Local control, cause-specific survival (CSS) and overall survival (OS) at 3 years were 91%, 97% and 90% for T1, and 100%, 82% and 74% for T2, respectively. The CSS and OS at 3 years were 100% and 100% for GGO and 83% and 59% for solid tumors, respectively (p=0.005). On univariate analysis, age and T stage were significantly associated with CSS, and age, the Charlson Comorbidity Index (CCI), and opacity were significantly associated with OS. On multivariate analysis, age and CCI were significantly associated with OS. As for toxicities, Grades 0, 1, 2 and 3 radiation pneumonitis occurred in 37.5%, 47.7%, 13.6% and 1.1% of patients, respectively. No Grade 4 or 5 radiation pneumonitis occurred, and no other toxicities of Grade 2 or above were observed.

CONCLUSION

Outcomes of SBRT for operable early stage NSCLC were as good as previous SBRT and surgery studies. Further investigation for selecting good SBRT candidates is warranted in high-risk operable patients.

Lobectomy and limited resection in small-sized peripheral non-small cell lung cancer

BACKGROUND

Although lobectomy is the standard surgical procedure for non-small cell lung cancer (NSCLC), recent studies show favorable outcomes after limited resection in patients with small-sized peripheral tumors. We conducted a randomized controlled trial of such patients to estimate postoperative outcomes and pulmonary function following these surgical techniques.

METHODS

Between 2005 and 2008, eligible patients with tumors of 2 cm or less were randomly assigned 1:1 to undergo lobectomy or limited resection; 32 and 33 NSCLC patients in each group, respectively, were analyzed. The primary end points were 5-year overall survival (OS) and disease-free survival (DFS), while the secondary end points were postoperative pulmonary function including forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁).

RESULTS

The 5-year OS rates were 93.8% and 90.9% in the lobectomy and limited resection groups, respectively (P=0.921). The 5-year DFS rates were 93.8% and 90.9% in the lobectomy and limited resection groups, respectively (P=0.714). These rates did not differ significantly between the two resection groups. The median postoperative/preoperative FVC ratios were 84.1% and 90.0% in the lobectomy and limited resection groups, respectively, while the median postoperative/preoperative FEV₁ ratios were 81.9% and 89.1%, respectively. Both ratios were significantly higher in the limited resection group (P=0.032 and P=0.005 for FVC and FEV₁ ratios, respectively).

CONCLUSIONS

A similar outcome, with more preserved postoperative pulmonary function, was observed in patients who underwent limited resection compared to those who underwent lobectomy. Ongoing large-scale multi-institutional prospective randomized trials of lobar versus sublobar resection in patients with small peripheral NSCLCs will hopefully provide definitive information about intentional limited resection of small peripheral tumors.

[Clinical Study of Surgical Treatment of Non-small Cell Lung Cancer 10 mm or Less in Diameter Under Video-assisted Thoracoscopy]

背景与目的

早期原发性非小细胞肺癌（non-small cell lung cancer, NSCLC）的手术切除及淋巴结切除的合理方式存在较大争议，本研究旨在探讨直径≤10 mm的原发NSCLC的微创切除及淋巴结切除的手术方式。

方法

对2013年7月-2016年3月在我院接受电视胸腔镜手术（video-assisted thoracic surgery, VATS）治疗并有明确病理诊断为NSCLC的共46例患者的临床资料进行回顾性分析。所有患者术前行薄层计算机断层扫描（computed tomography, CT），实性结节5例，混合性磨玻璃结节（mixed ground-glass opacity, mGGO）23例，纯磨玻璃结节（pure ground-glass opacity, pGGO）18例。根据患者具体情况采用不同术式，包括VATS肺叶切除和系统性淋巴结清扫，VATS肺楔形切除和选择性淋巴结切除，VATS肺段切除和选择性淋巴结切除，或仅采用VATS肺楔形切除。其中7例术前行CT引导下Hook-wire定位。

结果

VATS肺叶切除和系统性淋巴结清扫23例（mGGOs 15例，pGGOs 4例，实性结节4例），只有1例实性腺癌结节出现N2淋巴结转移，VATS肺楔形切除和选择性淋巴结切除5例（mGGOs 2例，pGGOs 3例）和VATS肺段切除和选择性淋巴结切除4例（mGGOs 2例，pGGOs 2例）均无淋巴结转移，仅采用VATS肺楔形切除14例（mGGOs 4例，pGGOs 9例，实性结节1例）。7例Hook-wire定位均成功。围手术期无重大并发症，随访1个月-26个月，平均（13.7±8.7）个月，无复发及转移。

结论

直径≤10 mm以mGGO和pGGO为表现的原发性NSCLC淋巴结转移率低，术中可以不进行淋巴结的清扫，实性结节应选择性淋巴结切除或系统性淋巴结清扫。高龄和心肺功能差的患者可以选择楔形切除或肺段切除。术前运用Hook-wire定位安全有效，可为VATS提供便利。

Prognosis and status of lymph node involvement in patients with adenocarcinoma in situ and minimally invasive adenocarcinoma-a systematic literature review and pooled-data analysis

BACKGROUND

Adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) have been brought up that substitute for bronchioloalveolar carcinoma (BAC), according to the new classification of lung adenocarcinoma. There has been increasing opinions that argues for the adjustment of lymph node disposition in patients with such early stage tumors. Therefore, we sought to overview the prognosis and status of lymph node involvement in AIS/MIA patients.

METHODS

PubMed, Springer and Ovid databases were searched for relevant studies. Data was extracted and results summarized to demonstrate the disposition of lymph nodes in AIS/MIA.

RESULTS

Twenty-three studies consisting of 6,137 lung adenocarcinoma were included. AIS/MIA accounted for 821 of the total 6,137. All included patients received curative surgery. After a review of the summarized data we found that only one patient (with MIA) had N1 node metastasis, N2 disease was not found in any of the included patients. In concordance with this, studies that reported 5-year disease free survival (5-year DFS) have almost 100% rate.

CONCLUSIONS

Our findings indicated that patients with AIS/MIA have good survival prognosis after surgical resection, and that recurrence and lymph node metastasis in these patients is rare. Therefore, we strongly encouraged further studies to determine the role of different lymph node disposition strategies.

Using frozen section to identify histological patterns in stage I lung adenocarcinoma of ≤ 3 cm: accuracy and interobserver agreement

AIMS

The IASLC/ATS/ERS classification of lung adenocarcinoma provides a prognostically significant histological subclassification. The aim of this study was to investigate the accuracy, limitations and interobserver agreement of frozen sections for predicting histological subtype.

METHODS AND RESULTS

Frozen section and permanent section slides from 361 resected stage I lung adenocarcinomas ≤ 3 cm in size were reviewed for predominant histological subtype and the presence or absence of lepidic, acinar, papillary, micropapillary and solid patterns. Fifty cases were additionally reviewed by three pathologists to determine interobserver agreement. To test the accuracy of frozen section in judging degree of invasion, five pathologists reviewed frozen section slides from 35 cases with a predominantly lepidic pattern. There was moderate agreement on predominant histological subtype between frozen sections and final diagnosis (κ = 0.565). Frozen sections had high specificity for micropapillary and solid patterns (94% and 96%, respectively), but sensitivity was low (37% and 69%, respectively). The interobserver agreement was satisfactory (κ > 0.6, except for the acinar pattern).

CONCLUSIONS

Frozen section can provide information on the presence of aggressive histological patterns-micropapillary and solid-with high specificity but low sensitivity. It was difficult to predict the predominant pattern on the basis of frozen sections, mostly because of sampling issues.

Outcomes of unresected ground-glass nodules with cytology suspicious for adenocarcinoma

BACKGROUND

Five-year survival rates for resected stage I adenocarcinoma approach 100%. Given previous studies describing the prolonged indolent natural history of ground-glass lesions suspicious for early adenocarcinoma, our purpose in this study was to determine if outcomes were different among patients who were observed for radiographic and biopsy suspected early adenocarcinoma compared with those who were resected immediately.

METHODS

We identified 63 patients with no prior history of lung adenocarcinoma who had undergone computer tomography-guided fine-needle aspiration of ground-glass opacities with cytology concerning for new early adenocarcinoma between January 2002 and December 2011. We compared the clinical outcomes of patients who were resected after abnormal cytology results and those who opted for watchful waiting.

RESULTS

Sixteen patients elected to observe their ground-glass nodules despite having suspicious cytology results, whereas 47 opted for immediate resection. Of the 16 observed patients, six (37.5%) ultimately demonstrated growth or increase solid component of the ground-glass nodule. Five of these patients elected for definitive therapy by surgical resection or radiation. There were no occurrences of distant metastasis or lung cancer-associated deaths in the observed group. Of the 47 resected patients, two developed metastatic disease, five developed new cancers in remaining lung, and three developed progression in existing ground-glass nodules.

CONCLUSIONS

Ground-glass lesions that were observed after biopsy did not demonstrate any increased rates of metastasis or cancer-related deaths and delayed resection does not seem to have a negative effect on outcomes.

Radiofrequency ablation for ground-glass opacity-dominant lung adenocarcinoma

PURPOSE

To evaluate retrospectively the clinical utility of lung radiofrequency (RF) ablation for the treatment of ground-glass opacity (GGO)-dominant lung adenocarcinoma.

MATERIALS AND METHODS

From August 2004 through May 2012, 33 consecutive patients (14 men and 19 women; mean age, 71.1 y; age range, 46-84 y) with 42 lung tumors having ≥ 50% GGO component received lung RF ablation. The mean maximum tumor diameter was 1.6 cm ± 0.9 (range, 0.7-4.0 cm). Feasibility, safety, local tumor progression, and survival were evaluated.

RESULTS

For the 42 RF sessions, after RF electrodes were placed in each target tumor, planned ablation protocols were completed in all sessions (100%; 42 of 42). No deaths related to the RF procedure occurred. Major and minor complication rates were 4.8% and 23.8%, respectively. Local tumor progression developed in 6 tumors (14.3%; 6 of 42) during a mean follow-up of 42 months ± 23 (range, 5-92 mo). Four of six tumors with local progression were controlled by repeated RF ablation. No evidence of disease was achieved in 31 of 33 patients (93.9%) at the end of the follow-up period. All but one patient (who died of brain hemorrhage) are alive today. Overall and cancer-specific survival rates were 100% and 100% at 1 year, 96.4% (95% confidence interval [CI], 77.5%-99.5%) and 100% at 3 years, and 96.4% (95% CI, 77.5%-99.5%) and 100% at 5 years, respectively.

CONCLUSIONS

Lung RF ablation is a feasible, safe, and useful therapeutic option to control GGO-dominant lung adenocarcinoma.

Reclassification of early stage pulmonary adenocarcinoma and its consequences

The classification of pulmonary adenocarcinoma has recently undergone several proposed changes. Among these, the most striking pertains to the discontinuation of the term "bronchioloalveolar carcinoma (BAC)" and its replacement by the terms "adenocarcinoma in situ (AIS)" or "minimally invasive adenocarcinoma (MIA)" for small solitary adenocarcinomas with either pure bronchiolalveolar growth or predominant bronchioloalveolar growth and ≤5 mm invasion, respectively, in resection specimens. The recommendation for these new concepts was based on discussion and review of the literature by a panel of experts from multiple disciplines. However, the results of a recent study investigating the topic of early stage adenocarcinoma (pT1N0M0) which was based on an actual series of cases, have raised questions as to the concept, validity and justification of such new terminology and have reinforced the need to evaluate actual cases that meet the newly proposed definitions and compare them in terms of patient outcome. This is even more important when proposing terminology that implies benign behavior and that could result in a false sense of security putting patients at risk for suboptimal treatment approaches. The controversies surrounding these issues are the subject of this work.

The 2011 IASLC/ATS/ERS pulmonary adenocarcinoma classification: a landmark in personalized medicine for lung cancer management

In 2011, three authoritative academic communities, International Association for the Study of Lung Cancer, the American Thoracic Society, and the European Respiratory Society (IASLC/ATS/ERS), published a novel lung adenocarcinoma histologic classification. The major modifications of this classification include the abolishment of the term "bronchioloalveolar carcinoma (BAC)", the establishment of new classification systems for resection and small biopsy or cytology specimens, the emphasis of molecular test and comprehensive histologic evaluation for tumor specimens, etc. This new lung adenocarcinoma classification signifies the era of personalized medicine comes to real-world practice in lung cancer field. Here, we introduce the background why the lung adenocarcinoma classification needs to be revised, and what we should consider in clinical practice according to this new classification.

Implementing the new IASLC/ATS/ERS classification of lung adenocarcinomas: results from international and Chinese cohorts

A new histologic classification of lung adenocarcinoma was proposed by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) in 2011 to provide uniform terminology and diagnostic criteria for multidisciplinary strategic management. This classification proposed a comprehensive histologic subtyping (lepidic, acinar, papillary, micropapillary, and solid pattern) and a semi-quantitative assessment of histologic patterns (in 5% increments) in an effort to choose a single, predominant pattern in invasive adenocarcinomas. The prognostic value of this classification has been validated in large, independent cohorts from multiple countries. In patients who underwent curative-intent surgery, those with either an adenocarcinoma in situ (AIS) or a minimal invasive adenocarcinoma have nearly 100% disease-free survival and are designated "low grade tumors". For invasive adenocarcinomas, the acinar and papillary predominant histologic subtypes were usually designated as "intermediate grade" while the solid and micropapillary predominant histologic subtypes were designated "high grade" tumors; this was based on the statistic difference of overall survival. This classification, coupled with additional prognostic factors [nuclear grade, cribriform pattern, high Ki-67 labeling index, thyroid transcription factor-1 (TTF-1) immunohistochemistry, immune markers, and (18)F-fluorodeoxyglucose uptake on positron emission tomography (PET)] that we have published on, could further stratify patients into prognostic subgroups and may prove helpful for individual patient care. With regard to Chinese oncologists, the implementation of this new classification only requires hematoxylin and eosin (H&E) stained slides and basic pathologic training, both of which require no additional costs. More importantly, this new classification system could provide informative data for better selection and stratification of clinical trials and molecular studies.

Pulmonary adenocarcinoma: implications of the recent advances in molecular biology, treatment and the IASLC/ATS/ERS classification

A decade ago, lung cancer could conveniently be classified into two broad categories-either the small cell lung carcinoma (SCLC), or the non-small cell lung carcinoma (NSCLC), mainly to assist in further treatment related decision making. However, the understanding regarding the eligibility of adenocarcinoma histology for treatments with agents such as pemetrexed and bevacizumab made it a necessity for NSCLC to be classified into more specific sub-groups. Then, the availability of molecular targeted therapy with oral tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib not only further emphasized the need for accurate sub-classification of lung cancer, but also heralded the important role of molecular profiling of lung adenocarcinomas. Given the remarkable advances in molecular biology, oncology and radiology, a need for felt for a revised classification for lung adenocarcinoma, since the existing World Health Organization (WHO) classification of lung cancer, published in the year 2004 was mainly a pathological system of classification. Thus, there was a combined effort by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS) with an effort to inculcate newly established perspectives from clinical, molecular and radiological aspects in evolving a modern classification for lung adenocarcinomas. This review provides a summary of the recent advances in molecular biology and molecular targeted therapy with respect to lung adenocarcinoma. Also, a brief summation of the salient recommendations provided in the IASLC/ATS/ERS classification of lung adenocarcinomas is provided. Lastly, a discussion regarding the future prospects with lung adenocarcinoma is included.

Comparative outcomes of elderly stage I lung cancer patients treated with segmentectomy via video-assisted thoracoscopic surgery versus open resection

INTRODUCTION

Video-assisted thorcacic surgery (VATS) is considered an alternative to open lobectomy for the treatment of non-small-cell lung cancer (NSCLC). Limited data are available, however, regarding the equivalence of open versus VATS segmental resections, particularly among elderly patients.

METHODS

From the Surveillance, Epidemiology, and End Results-Medicare database we identified 577 stage I NSCLC patients aged more than 65 years treated with VATS or open segmentectomy. We used propensity score methods to control for differences in the baseline characteristics of patients treated with VATS versus open segmentectomy. Outcomes included perioperative complications, need for intensive care unit, extended hospital stay, perioperative mortality, and survival.

RESULTS

Overall, 27% of patients underwent VATS. VATS-treated patients had lower rates of postoperative complications (odds ratio [OR]: 0.55, 95% confidence interval [CI]: 0.37-0.83), intensive care unit admissions (OR: 0.18, 95% CI: 0.12-0.28), and decreased length of stay (OR: 0.41, 95% CI: 0.21-0.81) after adjusting for propensity scores. Postoperative outcomes were not significantly different across groups after adjusting for surgeon characteristics. Overall (hazard ratio: 0.80, 95% CI: 0.60-1.06) and lung cancer-specific (hazard ratio: 0.71, 95% CI: 0.45-1.12) survival was similar across groups.

CONCLUSIONS

VATS segmentectomy can be safely performed among elderly NSCLC patients and is associated with equivalent postoperative and oncologic outcomes.

Unidirectionally thoracoscopic resection of lingual segment of the left upper pulmonary lobe

A patient with adenocarcinoma in situ was reported to undergo unidirectionally thoracoscopic resection of lingual segment of the left upper pulmonary lobe and lymphadenectomy in the order of the lingual segmental vein, the lingual segmental bronchus, the lingual segmental artery, and the pulmonary tissues of the lingual segment in turn. As the concepts of adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) are defined in the latest international classification of lung adenocarcinoma, pulmonary segmentectomy has been initially used in some multi-center clinical studies to treat these early lung cancer lesions. Pulmonary segmentectomy is currently one of the most minimally invasive lung surgeries, with its unique technical essentials different from those of pulmonary lobectomy. Some studies have shown that pulmonary segmentectomy for early lung cancer, especially for tumors with a diameter of less than 2 cm can achieve a similar long-term survival rate as pulmonary lobectomy, yet its effectiveness and safety should be confirmed in further large-scale prospective studies.

Wedge resection and segmentectomy in patients with stage I non-small cell lung carcinoma

The use of sublobar resections as definitive management in stage I non-small cell lung carcinoma is a controversial topic in the medical community. We intend to report the latest developments and trends in relative indications for each of the above-mentioned surgical approaches for the treatment of stage I non-small cell lung carcinoma as well as the results of studies regarding local recurrence, disease-free survival and five-year survival rates. We reviewed 45 prospective and retrospective studies conducted over the last 25 years listed in the Pubmed and Scopus electronic databases. Trials were identified through bibliographies and a manual search in journals. Authors, citations, objectives and results were extracted. No meta-analysis was performed. Validation of results was discussed. Segmentectomies are superior to wedge resections in terms of local recurrences and cancer-related mortality rates. Sublobar resections are superior to lobectomy in preserving the pulmonary parenchyma. High-risk patients should undergo segmentectomy, whereas lobectomies are superior to segmentectomies only for tumors >2 cm (T2bN0M0) in terms of disease-free and overall 5-year survival. In most studies no significant differences were found in tumors <2 cm. Disease-free surgical margins are crucial to prevent local recurrences. Systematic lymphadenectomy is mandatory regardless of the type of resection used. In sublobar resections with less thorough nodal dissections, adjuvant radiotherapy can be used. This approach is preferable in case of prior resection. In pure bronchoalveolar carcinoma, segmentectomy is recommended. Sublobar resections are associated with a shorter hospital stay. The selection of the type of resection in T1aN0M0 tumors should depend on characteristic of the patient and the tumor. Patient age, cardiopulmonary reserve and tumor size are the most important factors to be considered. However further prospective randomized trials are needed to investigate the efficacy of minimal resections in early lung cancer patients.

Computerized texture analysis of persistent part-solid ground-glass nodules: differentiation of preinvasive lesions from invasive pulmonary adenocarcinomas

PURPOSE

To retrospectively investigate the value of computerized three-dimensional texture analysis for differentiation of preinvasive lesions from invasive pulmonary adenocarcinomas (IPAs) that manifest as part-solid ground-glass nodules (GGNs).

MATERIALS AND METHODS

The institutional review board approved this retrospective study with a waiver of patients' informed consent. The study consisted of 86 patients with 86 pathologic analysis-confirmed part-solid GGNs (mean size, 16 mm ± 5.4 [standard deviation]) who had undergone computed tomographic (CT) imaging between January 2005 and October 2011. Each part-solid GGN was manually segmented and its computerized texture features were quantitatively extracted by using an in-house software program. Multivariate logistic regression analysis was performed to investigate the differentiating factors of preinvasive lesions from IPAs. Three-layered artificial neural networks (ANNs) with a back-propagation algorithm and receiver operating characteristic curve analysis were used to build a discriminating model with texture features and to evaluate its discriminating performance.

RESULTS

Pathologic analysis confirmed 58 IPAs (seven minimally invasive adenocarcinomas and 51 invasive adenocarcinomas) and 28 preinvasive lesions (four atypical adenomatous hyperplasias and 24 adenocarcinomas in situ). IPAs and preinvasive lesions exhibited significant differences in various histograms and volumetric parameters (P < .05). Multivariate analysis revealed that smaller mass (adjusted odds ratio, 0.092) and higher kurtosis (adjusted odds ratio, 3.319) are significant differentiators of preinvasive lesions from IPAs (P < .05). With mean attenuation, standard deviation of attenuation, mass, kurtosis, and entropy, the ANNs model showed excellent accuracy in differentiation of preinvasive lesions from IPAs (area under the curve, 0.981).

CONCLUSION

In part-solid GGNs, higher kurtosis and smaller mass are significant differentiators of preinvasive lesions from IPAs, and preinvasive lesions can be accurately differentiated from IPAs by using computerized texture analysis. Online supplemental material is available for this article.

Sublobar resection versus lobectomy in solid-type, clinical stage IA, non-small cell lung cancer

BACKGROUND

Recent studies have demonstrated that sublobar resection is not inferior to lobectomy for peripheral early lung cancer with ground-glass opacification. However, the effect of sublobar resection on solid-type early lung cancer is controversial. The aim of this study was to compare clinical outcomes of patients who have undergone sublobar resection or lobectomy for solid-type, early-stage, non-small cell lung cancer (NSCLC).

METHODS

This study was a retrospective review of the records of patients who underwent lobectomy or sublobar resection between March 2000 and September 2010 for clinical stage IA NSCL. Patients with pure ground-glass opacities or death within 30 days after surgery were excluded. Disease-free interval, survival, and prognostic factors were analyzed.

RESULTS

Thirty-one patients and 133 patients underwent sublobar resection and lobectomy, respectively. There were significant differences in age (P < 0.001), cardiovascular disease (P = 0.001), and diffusing capacity of the lung for carbon monoxide (DLCO) (P < 0.001). The patients with lobectomy had a significantly longer disease-free interval (P < 0.001) and survival (P = 0.001). By multivariate analysis, sublobar resection (P = 0.011), lymphatic vessel invasion (P = 0.006), and number of positive lymph nodes (P = 0.028) were predictors for survival. Sublobar resection (P < 0.001), visceral pleural invasion (P = 0.002), and lymphatic vessel invasion (P < 0.001) were predictors for disease-free interval.

CONCLUSIONS

Lobectomy should remain the standard surgical procedure for solid-type, clinical stage IA, NSCLC.

Pulmonary adenocarcinoma T1N0M0 and its classification

Over the last decade, use of the term bronchioloalveolar carcinoma (BAC) has come under constant scrutiny as some consider it an anachronism or a term that provides incorrect information about this neoplasm. To that extent, it has recently been suggested to replace the term BAC with that of in situ adenocarcinoma (AIS) or minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure bronchioloalveolar growth (AIS) or predominant bronchioloalveolar growth and ≤5-mm invasion (MIA). However, as of today, there is no comprehensive study of these tumors, and most of what has been published in this context is based on a review of the literature that focused on scattered short series of cases describing either small adenocarcinomas or BAC. More recently, a large series of cases of a more comprehensive nature that included all early-stage adenocarcinomas (T1N0M0) has cast some doubt regarding the need for the proposed change in nomenclature. At the same time, it was suggested that if indeed that notion is maintained, a more serious and comprehensive study of actual cases must be undertaken. The details of the issues surrounding this subject are presented in this review.

The pivotal role of pathology in the management of lung cancer

The last decade has seen significant advances in our understanding of lung cancer biology and management. Identification of key driver events in lung carcinogenesis has contributed to the development of targeted lung cancer therapies, heralding the era of personalised medicine for lung cancer. As a result, histological subtyping and molecular testing has become of paramount importance, placing increasing demands on often small diagnostic specimens. This has triggered the review and development of the first structured classification of lung cancer in small biopsy/cytology specimens and a new classification of lung adenocarcinoma from the IASLC/ATS/ERS. These have enhanced the clinical relevance of pathological diagnosis, and emphasise the role of the modern surgical pathologist as an integral member of the multidisciplinary team, playing a crucial role in clinical trials and determining appropriate and timely management for patients with lung cancer.

Prognostic significance of adenocarcinoma in situ, minimally invasive adenocarcinoma, and nonmucinous lepidic predominant invasive adenocarcinoma of the lung in patients with stage I disease

According to the IASLC/ATS/ERS classification, the lepidic predominant pattern consists of 3 subtypes: adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and nonmucinous lepidic predominant invasive adenocarcinoma. We reviewed tumor slides from 1038 patients with stage I lung adenocarcinoma, recording the percentage of each histologic pattern and measuring the invasive tumor size. Tumors were classified according to the IASLC/ATS/ERS classification: 2 were AIS, 34 MIA, and 103 lepidic predominant invasive. Cumulative incidence of recurrence (CIR) was used to estimate the probability of recurrence. Patients with AIS and MIA experienced no recurrences. Patients with lepidic predominant invasive tumors had a lower risk for recurrence (5-y CIR, 8%) than nonlepidic predominant tumors (n=899; 19%; P=0.003). Patients with >50% lepidic pattern tumors experienced no recurrences (n=84), those with >10% to 50% lepidic pattern tumors had an intermediate risk for recurrence (n=344; 5-y CIR, 12%), and those with ≤10% lepidic pattern tumors had the highest risk (n=610; 22%; P<0.001). CIR was lower for patients with ≤2 cm tumors than for those with >2 to 3 cm tumors (for both total and invasive tumor size), with the difference more pronounced for invasive tumor size (5-y CIR, 13% vs. 21% [total size; P=0.022] and 12% vs. 27% [invasive size; P<0.001]). Most patients with lepidic predominant adenocarcinoma who experienced a recurrence had potential risk factors, including sublobar resection with close margins (≤0.5 cm; n=2), 20% to 30% micropapillary component (n=2), and lymphatic or vascular invasion (n=2). It therefore may be possible to identify lepidic predominant adenocarcinomas that carry a low or high risk for recurrence.

Analysis of feasibility and safety of complete video-assisted thoracoscopic resection of anatomic pulmonary segments under non-intubated anesthesia

OBJECTIVE

To explore the feasibility and safety of complete video-assisted thoracoscopic surgery (C-VATS) under non-intubated anesthesia for the resection of anatomic pulmonary segments in the treatment of early lung cancer (T1N0M0), benign lung diseases and lung metastases.

METHODS

The clinical data of patients undergoing resection of anatomic pulmonary segments using C-VATS under non-intubated anesthesia in the First Affiliated Hospital of Guangzhou Medical University from July 2011 to November 2013 were retrospectively analyzed to evaluate the feasibility and safety of this technique.

RESULTS

The procedures were successfully completed in 15 patients, including four men and eleven women. The average age was 47 [21-74] years. There were ten patients with adenocarcinoma, one with pulmonary metastases, and four with benign lung lesions. The resected sites included: right upper apical segment, two; right lower dorsal segment, one; right lower basal segment, two; left upper lingular segment, three; left upper apical segment, one; left upper anterior apical segment, two; left upper posterior segment, one; left lower basal segment, one; left upper posterior and apical segments, one; and left upper anterior and apical segments plus wedge resection of the posterior segment, one. One case had intraoperative bleeding, which was controlled with thoracoscopic operation and no blood transfusion was required. No thoracotomy or perioperative death was noted. Two patients had postoperative bleeding without the need for blood transfusions, and were cured and discharged. The pathologic stage for all patients with primary lung cancer was IA. After 4-19 months of follow-up, no tumor recurrence and metastasis was found. The overall mean operative length was 166 minutes (range 65-285 minutes), mean blood loss 75 mL (range 5-1,450 mL), mean postoperative chest drainage 294 mL (range 0-1,165 mL), mean chest drainage time 2 days (range 0-5 days), and mean postoperative hospital stay 5 days (range 3-8 days).

CONCLUSIONS

Complete video-assisted throacoscopic segmentectomy under anesthesia without endotracheal intubation is a safe and feasible technique that can be used to treat a selected group of IA patients with primary lung cancer, lung metastases and benign diseases.

Tumour standardized uptake value on positron emission tomography is a novel predictor of adenocarcinoma in situ for c-Stage IA lung cancer patients with a part-solid nodule on thin-section computed tomography scan

OBJECTIVES

Adenocarcinoma in situ (AIS), which is considered to be pathologically non-invasive in the new International Association for the Study of Lung Cancer/the American Thoracic Society/the European Respiratory Society classification, might be present in patients who show a part-solid nodule on thin-section computed tomography (CT) scan.

METHODS

Between 2008 and 2011, 556 clinical Stage IA (c-Stage IA) lung cancer patients underwent pulmonary resection. For all the patients, the findings obtained by preoperative thin-section CT were reviewed and categorized as pure ground-glass nodule (GGN), part-solid nodule or pure-solid nodule based on the findings on thin-section CT, i.e. based on the consolidation/tumour ratio (CTR). A part-solid nodule was defined as a tumour with 0 < CTR < 1.0, which indicated focal nodular opacity that contained both solid and GGN components. All the patients were evaluated by positron emission tomography (PET), and the maximum standardized uptake value (SUVmax) was recorded. Several clinicopathological features were investigated to identify predictors of AIS in clinical Stage IA lung cancer patients with a part-solid nodule radiologically, using multivariate analyses.

RESULTS

One-hundred and twelve c-Stage IA lung cancer patients showed a part-solid appearance on thin-section CT. Among them, AIS was found in 10 (32%) of the tumours with 0 < CTR ≤ 0.5, in contrast to 3 (5%) with 0.5 < CTR < 1.0. According to multivariate analyses, SUVmax and CTR significantly predicted AIS in patients with a part-solid nodule (P = 0.04, 0.02). The mean SUVmax of the patients with AIS was 0.57 (0-1.6). Moreover, in the subgroup of part-solid nodule with a SUVmax of ≤1.0 and a CTR of ≤0.40, which were calculated as cut-off values for AIS based on the results for a receiver operating characteristic curve, 6 (40%) patients with these criteria showed a pathological non-invasive nature, even patients with a part-solid nodule.

CONCLUSIONS

Among c-Stage IA adenocarcinoma with a part-solid nodule on thin-section CT scan, an extremely low level of SUVmax could reflect a pure GGN equivalent radiologically and AIS pathologically. The preoperative tumour SUVmax on PET could yield important information for predicting non-invasiveness in patients with a part-solid nodule.