Limited resection trial for pulmonary ground-glass opacity nodules: fifty-case experience

Ten-year follow-up outcomes of limited resection trial for radiologically less-invasive lung cancer

BACKGROUND

The JCOG0804/WJOG4507L single-arm confirmatory trial indicated a satisfactory 10-year prognosis for patients who underwent limited resection for radiologically less-invasive lung cancer. However, only one prospective trial has reported a 10-year prognosis.

METHODS

We conducted a multicenter prospective study coordinated by the National Cancer Center Hospital East and Kanagawa Cancer Center. We analyzed the long-term prognosis of 100 patients who underwent limited resection of a radiologically less-invasive lung cancer in the peripheral lung field. We defined radiologically less-invasive lung cancer as lung adenocarcinoma with a maximum tumor diameter of ≤2 cm, tumor disappearance ratio of ≥0.5 and cN0. The primary endpoint was the 10-year local recurrence-free survival.

RESULTS

Our patients, with a median age of 62 years, included 39 males. A total of 58 patients were non-smokers; 87 had undergone wide wedge resection and 9 underwent segmentectomy. A total of four cases were converted to lobectomy because of the presence of poorly differentiated components in the frozen specimen or insufficient margin with segmentectomy. The median follow-up duration was 120.9 months. The 10-year recurrence-free survival and overall survival rates of patients with lung cancer were both 96.0%. Following the 10-year long-term follow-up, two patients experienced recurrences at resection ends after wedge resection.

CONCLUSIONS

Limited resection imparted a satisfactory prognosis for patients with radiologically less-invasive lung cancer, except two cases of local recurrence >5 years after surgery. These findings suggest that patients with this condition who underwent limited resection may require continued follow-up >5 years after surgery.

Sublobar resection in non-small cell lung cancer: patient selection criteria and risk factors for recurrence

OBJECTIVE

To validate selection criteria for sublobar resection in patients with lung cancer with respect to recurrence, and to investigate predictors for recurrence in patients for whom the criteria are not suitable.

METHODS

Patients who underwent sublobar resection for lung cancer between July 2010 and December 2018 were retrospectively included. The criteria for curative sublobar resection were consolidation-to-tumor ratio ≤0.50 and size ≤3.0 cm in tumors with a ground-glass opacity (GGO) component (GGO group), and size of ≤2.0 cm and volume doubling time ≥400 days in solid tumors (solid group). Cox regression was used to identify predictors for time-to-recurrence (TTR) in tumors outside of these criteria (non-curative group).

RESULTS

Out of 530 patients, 353 were classified into the GGO group and 177 into the solid group. In the GGO group, the 2-year recurrence rates in curative and non-curative groups were 2.1 and 7.7%, respectively (p = 0.054). In the solid group, the 2-year recurrence rates in curative and non-curative groups were 0.0 and 28.6%, respectively (p = 0.03). Predictors of 2-year TTR after non-curative sublobar resection were pathological nodal metastasis (hazard ratio [HR], 6.63; p = 0.02) and lymphovascular invasion (LVI; HR, 3.28; p = 0.03) in the GGO group, and LVI (HR, 4.37; p < 0.001) and fibrosis (HR, 3.18; p = 0.006) in the solid group.

CONCLUSION

The current patient selection criteria for sublobar resection are satisfactory. LVI was a predictor for recurrence after non-curative resection.

ADVANCES IN KNOWLEDGE

This result supports selection criteria of patients for sublobar resection. LVI may help predict recurrence after non-curative sublobar resection.

Intraoperative computed tomography of a resected lung inflated with air to verify safety surgical margin

Background

During sublobar resection for small, indistinct lung cancer, surgeons may be uncertain as to whether or not the target lesion has been resected and the surgical margin is sufficient. We herein report our procedure for confirming the success of sublobar resection without incising the resected specimen.

Methods

We reviewed our initial experience of 12 patients with intrapulmonary lesions (consolidation diameter ≤1 cm) who underwent thoracoscopic pulmonary wedge resection using autostapler. Six patients had primary adenocarcinoma showing part solid lesion, and remaining six patients had metastatic carcinoma showing purely solid lesion. Intraoperatively, the resected specimen was inflated with air and subjected to computed tomography (CT). The maximum tumor diameter and surgical margin length were measured intraoperatively on CT and postoperatively on formalin-fixed specimen. Surgical stump cytology was also done to verify surgical margin.

Results

According to the intraoperative CT, complete resection was confirmed in all patients. The intraoperative CT-based maximum tumor diameter closely correlated with the macroscopically measured one (r=0.971, P<0.0001). However, the tumor shrunk after formalin-fixation by 16.0% in patients with primary lung cancer (P<0.01), but not in patients with metastatic lung cancer. The intraoperative CT-based margin length closely correlated with the macroscopically measured one (r=0.984, P<0.0001). However, the margin shrunk after formalin-fixation in both patients with primary lung cancer and metastatic lung cancer, by 15.1% and 15.7%, respectively. Stump cytology was negative in all patients. Consequently, no recurrence was found during postoperative follow-up of 23 months (range, 14-31 months).

Conclusions

Intraoperative CT is reliable for diagnosing the presence of a target lesion within the resected specimen as well as for estimating the surgical margin length in patients undergoing sublobar resection for intrapulmonary indistinct lesions.

Invasive Prediction of Ground Glass Nodule Based on Clinical Characteristics and Radiomics Feature

Objective: To explore the diagnostic value of CT radiographic images and radiomics features for invasive classification of lung adenocarcinoma manifesting as ground-glass nodules (GGNs) in computer tomography (CT).

Methods: A total of 312 GGNs were enrolled in this retrospective study. All GGNs were randomly divided into training set (n = 219) and test set (n = 93). Univariate and multivariate logistic regressions were used to establish a clinical model, while the minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) algorithm were used to select the radiomics features and construct the radiomics model. A combined model was finally built by combining these two models. The performance of these models was assessed in both training and test set. A combined nomogram was developed based on the combined model and evaluated with its calibration curves and C-index.

Results: Diameter [odds ratio (OR), 1.159; p ＜ 0.001], lobulation (OR, 2.953; p = 0.002), and vascular changes (OR, 3.431; p ＜ 0.001) were retained as independent predictors of the invasive adenocarcinoma (IAC) group. Eleven radiomics features were selected by mRMR and LASSO method to established radiomics model. The clinical model and radiomics mode showed good predictive ability in both training set and test set. When two models were combined, the diagnostic area under the curve (AUC) value was higher than the single clinical or radiomics model (training set: 0.86 vs. 0.83 vs. 0.82; test set: 0.80 vs. 0.78 vs. 0.79). The constructed combined nomogram could effectively quantify the risk degree of 3 image features and Rad score with a C-index of 0.855 (95%: 0.805∼0.905).

Conclusion: Radiographic and radiomics features show high accuracy in the invasive diagnosis of GGNs, and their combined analysis can improve the diagnostic efficacy of IAC manifesting as GGNs. The nomogram, serving as a noninvasive and accurate predictive tool, can help judge the invasiveness of GGNs prior to surgery and assist clinicians in creating personalized treatment strategies.

Elucidating the anatomy of the quadrivial pattern of the right upper lobe bronchus using 3D-CT images

Background

A preoperative understanding of the thoracic anatomy of the patients with the quadrivial pattern of branching of the right upper lobe is key to successful surgery. We analyzed the quadrivial pattern of division of the right upper lobe bronchus of patients using three-dimensional (3D) computed tomography (CT) angiography and bronchography.

Methods

A total of 212 consecutive adult patients who had undergone thoracic CT scans before surgery at the Zhujiang Hospital of the Southern Medical University from August 2020 to August 2021 was used for retrospective study. The 3D-CT images were taken using Mimics software. Radiology technicians processed all the 3D images, and thoracic surgeons confirmed the validity of all the reconstructions.

Results

Six (2.83%) were identified as having a quadrivial pattern of division of the right upper lobe bronchus with 1 female, and 5 males. Based on the number of pulmonary artery branches, 5 (83.3%) and 1 (16.7%) were classified as “trunk superior (Tr.sup) + ascending artery (A.asc) and Tr.sup + trunk inferior (Tr.inf) + ascending artery (A.asc) (1/6, 16.7%). Based on the number of ascending artery branches, the patients were also divided into type A (3/6, 50%) and type B (3/6, 50%). The patients were also divided into 1 of the following three types based on the origins of the A2: (I) A2 originates from A6 (1/6, 16.7%); (II) A2 originates from the pulmonary trunk (4/6, 66.7%); and (III) A2a originates from A3, and A2b originates from the pulmonary artery stem (1/6, 16.7%). According to the number of A1b branches, patients were divided into two types: (I) 1 branch (4/6, 66.7 %); and (II) 2 branches (2/6, 33.3 %). In the present study, anterior + central type was observed which classified into two types: (I) type Iab, the anterior vein ran from V1a to V1b (4/6, 66.7%); and (II) type Ib, the anterior vein ran from V1b only (2/6, 33.3%).

Conclusions

3D-CT was successfully used for analyzing the quadrivial bronchovascular patterns of the right upper lobe bronchus. Our study provides certain references to perform anatomical pulmonary segmentectomy, which should improve the success rate of operations.

Pearls and Pitfalls in Postsurgical Imaging of the Chest

A variety of surgical procedures are utilized to treat a spectrum of cardiopulmonary diseases. In the imaging of patients in the post-operative period, it is important to have an understanding of surgical techniques including invasive and minimally invasive procedures and the expected postsurgical findings. Knowledge of certain patient risk factors, various complications associated with specific surgical procedures, and a keen attention to detail are essential to avoid misinterpretation and delay diagnosis. Prompt detection of potential complications allows timely intervention, thereby, optimizing patient outcomes in the post-operative period.

The Impact of EGFR Tyrosine Kinase Inhibitor on the Natural Course of Concurrent Subsolid Nodules in Patients with Non-Small Cell Lung Cancer

Purpose

The role of epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs) in the management of persistent subsolid nodules (SSNs) is unclear. This study aimed to investigate the impact of EGFR-TKIs on concurrent SSNs in patients with stage IV non–small cell lung cancer (NSCLC).

Materials and Methods

Patients who received an EGFR-TKI for at least 1 month for stage IV NSCLC and had concurrent SSN(s) that had existed for at least 3 months on chest computed tomography were included in this retrospective study. Size change of each nodule before and after EGFR-TKI therapies were evaluated using a cutoff value of 2 mm; increase (≥ 2 mm), decrease (≤ −2 mm), and no change (−2 mm < size change < +2 mm).

Results

A total of 77 SSNs, 51 pure ground-glass (66.2%) and 26 part-solid nodules (33.8%), were identified in 59 patients who received gefitinib (n=45) and erlotinib (n=14). Among 58 EGFR mutation analysis performed for primary lung cancer, 45 (77.6%) were EGFR mutant. The proportions of decrease group were 19.5% (15/77) on per-nodule basis and 25.4% (15/59) on per-patient basis. Four SSNs (5.2%) disappeared completely. On per-patient based multivariable analysis, EGFR exon 19 deletion positivity for primary lung cancer was associated with a decrease after initial EGFR-TKI therapy (adjusted odds ratio, 4.29; 95% confidence interval, 1.21 to 15.29; p=0.025).

Conclusion

Approximately 20% of the concurrent SSNs decreased after the initial EGFR-TKI therapy. EGFR exon 19 deletion positivity for primary lung cancer was significantly associated with the size change of concurrent SSNs.

Long-term Outcomes After Lung Cancer Resection in Smokers: Analysis of the National Lung Screening Trial

BACKGROUND

Smoking is a known risk factor for perioperative complications after lung resection; however, little data exists looking at the impact of smoking status (current versus former) on long-term oncologic outcomes after lung cancer surgery. We sought to compare overall survival (OS), progression-free survival (PFS), and cancer-specific mortality (CSM) in current and former smokers using data from the National Lung Screening Trial (NLST). Additionally, we performed subset analysis in current smokers in order to evaluate the effect of modern surgical techniques on long-term outcomes.

METHODS

Patients with clinical stage IA or IB NSCLC who underwent upfront resection within 180 days of diagnosis were identified in the NLST database. Cox proportional hazard regression models were used to assess differences in patient and treatment characteristics with respect to OS and PFS, with a cause-specific hazard model used for CSM.

RESULTS

A total of 593 patients were included in the study (269 former smokers, 324 current smokers). Lobar resection (LR) was performed more often than sublobar resection (SLR) (481 vs. 112), and thoracotomy was performed more often than thoracoscopy (482 vs. 86). Comparison of current versus former smokers showed no difference in OS or PFS after resection. Higher CSM was seen in current smokers (p = 0.049). Subset analysis of current smokers revealed no difference in OS or PFS between sub-lobar and lobar resection or thoracotomy and thoracoscopy. Although higher CSM was associated with thoracoscopy versus thoracotomy in this group, this finding was limited by a relatively small thoracoscopy sample size of 44 patients (p = 0.026).

CONCLUSION

Our analysis of the NLST database shows no significant difference in OS and PFS when comparing current and former smokers undergoing resection for stage I NSCLC. Active smoking status was associated with higher CSM. Subset analysis of current smokers showed no difference in OS or PFS between sub-lobar and lobar resection or thoracotomy and thoracoscopy. Higher CSM was seen in current smokers who underwent thoracoscopy compared to thoracotomy; however, this finding was limited by a small sample size.

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.

Fluorescence visualization of the intersegmental plane by bronchoscopic instillation of indocyanine green into the targeted segmental bronchus: determination of the optimal settings

Objective

To determine the appropriate amount of indocyanine green for bronchial insufflation.

Methods

We enrolled 20 consecutive patients scheduled for anatomical segmentectomy in the Kochi Medical School Hospital. After inducing general anesthesia, 6 to 60 mL of 200-fold-diluted indocyanine green (0.0125 mg/mL) was insufflated into the subsegmental bronchi in the targeted pulmonary segmental bronchus. The volume of the targeted pulmonary segments was calculated using preoperative computed tomography. Fluorescence spread in the segmental alveoli was visualized using a dedicated near-infrared thoracoscope.

Results

The targeted segment was uniformly visualized by indocyanine green fluorescence in 16/20 (80.0%) cases after insufflating indocyanine green. A receiver operating characteristic curve indicated that the area under the curve was 0.984; the optimal cut-off volume of diluted indocyanine green for insufflation was 8.91% of the calculated targeted pulmonary segment volume.

Conclusions

The setting for indocyanine green insufflation was optimized for near-infrared fluorescence image-guided anatomical segmentectomy. By injecting the correct amount of indocyanine green, fluorescence-guided anatomical segmentation may be performed more appropriately.

The accuracy of cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic marking of multiple small-sized pulmonary nodules in a hybrid operating room: a retrospective cohort study

Background

For the minimally invasive excision of small-sized pulmonary nodules, bronchoscopic markings are increasingly being performed owing to advancements in video-assisted thoracic surgery (VATS). Hybrid operating room equipment is utilized for bronchoscopic VATS markings. We aimed to compare the marking accuracy between bronchoscopic VATS and other marking techniques such as computed tomography-guided percutaneous marking and conventional X-ray fluoroscopy-guided bronchoscopic marking.

Methods

Patients with small-sized pulmonary nodules scheduled to undergo VATS were enrolled in the study. A mixture of 50 to 100 µL of diluted indocyanine green and iopamidol was injected adjacent to the pulmonary nodules as a VATS marker. Patients receiving each of the three image-guided techniques were categorized into group A (computed tomography-guided percutaneous injection), group B (X-ray fluoroscopy-guided virtual bronchoscopy-assisted bronchoscope injection), and group C (cone-beam computed tomography and augmented fluoroscopy-guided virtual bronchoscope-assisted bronchoscopic injection in the hybrid operating room). VATS marking accuracy and procedural complications were compared among the three groups.

Results

In total, 61 patients with 73 pulmonary nodules were eligible for analysis. VATS marking was successful for 15/16 nodules in group A, 28/30 nodules in group B, and 25/27 nodules in group C. Marking accuracy was 5.75±4.59, 15.00±14.02, and 6.05±6.11 (mm), respectively. Multiple markings were successful in 0/1 (0%), 5/6 (83.3%), and 5/5 (100.0%) nodules in groups A, B, and C, respectively. A small pneumothorax occurred in 3/15 (20.0%) patients in group A.

Conclusions

The cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic approach performed in a hybrid operating room is accurate and equivalent to the computed tomography-guided percutaneous approach, and it enables the VATS marking of multiple pulmonary nodules without causing a secondary pneumothorax.

Adjuvant treatment can improve prognosis in patients with non-small cell lung cancer ≤3 cm after sublobectomy: a propensity score analysis

Background

Numerous retrospective studies have reported that sublobectomy has a poorer prognosis than lobectomy in patients with early-stage lung cancer. The purpose of this study was to determine whether adjuvant treatment could improve the prognosis of patients with non-small cell lung cancer (NSCLC) ≤3 cm after sublobectomy.

Methods

We collected data from 17,763 patients with T1N0M0 NSCLC after surgery from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Kaplan-Meier curves were generated to compare the overall survival (OS) rates and the lung cancer-specific survival (LCSS) rates. Cox proportional hazards regressions were performed to discover the independent risk factors for both the OS and LCSS rates.

Results

Lobectomy was performed in 12,428 cases and sublobectomy was performed in 5,335 cases. In the sublobectomy group, among the 394 patients treated with adjuvant therapy, larger tumor diameter, a lower number of lymph node dissections, and more wedge resections were observed in the patients treated with adjuvant therapy. In the subsequent survival analysis, the OS and LCSS rates of adjuvant therapy patients showed a significant survival advantage over those treated with sublobectomy alone (P<0.05). The survival analysis was performed again after propensity match scoring, generating similar results (P<0.05). There was still a significant difference in OS between adjuvant therapy and lobectomy alone (P<0.05).

Conclusions

Chemoradiotherapy can improve the OS of patients with NSCLC ≤3 cm after sublobectomy and reduce death caused by tumors. Therefore, when patients cannot tolerate lobectomy or are given inappropriate sublobectomy, adjuvant therapy can improve the prognosis of patients.

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.

Approach to the Subsolid Nodule

Most focal persistent ground glass nodules (GGNs) do not progress over 10 years. Research suggests that GGNs that do not progress, those that do, and solid lung cancers are fundamentally different diseases, although histologically they seem similar. Surveillance of GGNs to identify those that gradually progress is safe and does not risk losing a window. GGNs with 5 mm solid component or less than 10 mm consolidation (mediastinal and lung windows, respectively, on thin slice CT) are highly curable with resection. The optimal type of resection is unclear; sublobar resection is reasonable but an adequate margin is critically important.

Novel Imprint Cytological Classification for Small Pulmonary Adenocarcinoma Using Surgical Specimens: Comparison with the 8th Lung Cancer Staging System and Histopathological Classification

Objectives: Small-size lung lesions suspected of being cancer are now often being identified on computed tomography. Correspondingly, a new lung cancer staging system has been proposed by the International Association for the Study of Lung Cancer (IASLC), in which the T1 factor and adenocarcinoma are re-subclassified. Previously, we proposed an intraoperative cytological diagnosis and its classification of small-size lung adenocarcinoma, which correlated significantly with clinical malignancy, to be used for selecting the surgical strategy. In the current study, the correlation of our intraoperative cytological classification with the new 8th IASLC classification was investigated. Materials and Methods: A total of 139 consecutive small-size lung adenocarcinoma cases were surgically resected from 2000 to 2006 and included in this study. Intraoperative stump imprint cytology using these specimens was performed, and the cases were classified into 5 groups based on our classification. The cytological classification was compared with the IASLC classification and the WHO histopathological grading. Results: According to our classification, 32 patients were in Group I, 38 in Group II, 24 in Group III, 27 in Group IV, and 18 in Group V. Compared with the IASLC classification, most of Group I was pTis or pT1mi, and most of Group II was pT1mi or pT1a (p<0.001). There was also a significant relationship between lymph node metastasis and our cytological classification (p<0.001). The histological patterns according to the WHO classification also had a significant relationship with our classification (p<0.001). Conclusion: Our cytological classification correlated not only with the T classification, but also with the adenocarcinoma subclassification of the 8th IASLC classification.

Intraoperative Diagnosis and Surgical Procedure with Imprint Cytology for Small Pulmonary Adenocarcinoma

Objectives: For patients with multiple small-sized pulmonary cancers, a lobectomy can disrupt future therapeutic options for other lesions. It was recently reported that limited pulmonary resections were not inferior to lobectomy for the management of selected peripheral small-sized pulmonary adenocarcinomas. Patients with adenocarcinoma in situ or minimally invasive adenocarcinoma, as proposed by the International Association for the Study of Cancer classification, have been reported to have 100% survival after 5 years. However, that classification can be applied postoperatively. Since 2005, we have been intentionally performing limited pulmonary resection procedures for small-sized adenocarcinoma cases based on intraoperative imprint cytological diagnosis and our classification (Nakayama-Higashiyama's classification). Materials and Methods: A total of 120 consecutive cases were included in this study. Lung tumors were removed intraoperatively by wedge resection, and stump smear cytology was performed, from which the cases were classified into 5 groups based on our classification. When the tumor was classified as Group I or II, the operation was finished. When diagnosed as a more advanced classification, a lobectomy and lymph node dissection were additionally performed. Results: The 5-year survival rate for Group I and II was 100%, while those for Group III and IV-V were 95.8% and 94.4%, respectively. The 5-year disease-free survival rates for Group I and Group II were 100% and 97.1%, respectively, and for Group III and IV-V they were 100% and 94.1%, respectively. Conclusion: Use of cytological findings along with Nakayama-Higashiyama's classification for determining operation procedure is effective for treatment of patients with small-sized pulmonary adenocarcinoma.

Surgeons' preference sublobar resection for stage I NSCLC less than 3 cm

Background

This study aimed to compare survival between standard lobectomy and surgeons' preference sublobar resection among patients with stage I non‐small cell lung cancer (NSCLC).

Methods

Medical records of patients undergoing pulmonary resection between 2006 and 2016 were reviewed retrospectively. Differences in disease‐free survival (DFS) and DFS‐associated factors between patients receiving lobectomy and surgeons' preference sublobar resection were analyzed after 1‐1 propensity score‐matching (n = 119 per group).

Results

In total, 1064 pathological stage I NSCLC patients were identified, including 816 (76.7%) who underwent lobectomy, 111 (10.4%) who underwent sublobar resection as a compromised procedure (medically unfit), and 137 (12.9%) who underwent surgeons' preference sublobar resection. Rates of five‐year DFS for patients undergoing lobectomy, medically unfit, and surgeons' preference sublobar resection were 88.7%, 71.0%, and 93.4%, respectively (P < 0.001). Multivariable Cox regression analysis demonstrated that radiological solid‐appearance (adjusted hazard [aHR] = 2.908, P = 0.003), PL2 invasion (aHR = 1.970, P = 0.024), and angiolymphatic invasion (aHR = 2.202, P = 0.005) were significantly associated with lower DFS after adjusting for surgeons' preference sublobar resection (aH = 1.031, P = 0.939). Subgroup analysis of all 403 solid‐dominant patients demonstrated equivalent five‐year DFS between surgeons' preference sublobar resection and lobectomy (87.7% and 84.1%, respectively, P = 0.721). Propensity‐matched analysis showed no differences in five‐year DFS in stage I NSCLC patients undergoing lobectomy or surgeons' preference sublobar resection (90.5% vs. 93.4% P = 0.510), and DFS for surgeons' preference sublobar resection remained an insignificant factor (aHR = 0.894, P = 0.834).

Conclusions

Carefully selected patients who have undergone surgeons' preference sublobar resection have comparable outcomes to those receiving lobectomy for stage I NSCLC <3 cm.

Key points

Significant findings of the study Intended sublobar resection has a good outcome. What this study adds Sublobar resection is applicable for stage I NSCLC <3 cm.

Tumor Spread Through Air Spaces Is a Predictor of Occult Lymph Node Metastasis in Clinical Stage IA Lung Adenocarcinoma

INTRODUCTION

In patients with stage IA lung adenocarcinoma (ADC), sublobar resection and tumor spread through air spaces (STAS) are associated with high rates of locoregional recurrence, half of which occur within the regional lymph nodes (LNs). Our objectives were to investigate the association between occult LN metastasis (ONM) and STAS and to assess their prognostic value in patients with clinical stage IA lung ADC.

METHODS

The association between STAS and ONM was analyzed in patients who underwent lobectomy and LN dissection for clinical stage IA lung ADC (n = 809). Multivariable logistic regression analysis was carried out to identify predictors of ONM. Site-specific recurrence by surgical procedure was investigated in patients with pathologic node-negative disease (n = 1055) using a competing risk approach.

RESULTS

ONM was identified in 129 patients (16%)-one-third of ONMs were located only in intrapulmonary nodes. STAS was more common in patients with ONM than in those without ONM (67% versus 39%; p < 0.001) and in patients with multiple ONMs than in those with a single ONM (86%-89% versus 60%-67%). STAS was a significant predictor of ONM (p = 0.004) on multivariable analysis, independent of tumor size, maximum standardized uptake value, and lymphovascular invasion. In patients with STAS-positive ADC (high ONM risk), the risk of recurrence in the treated lobe and regional LNs increased as the extent of resection decreased (recurrence risk: lobectomy < segmentectomy < wedge resection). In patients with STAS-negative ADC, the risk of locoregional recurrence did not differ by procedure type.

CONCLUSIONS

Presence of STAS predicts ONM in patients with clinical stage IA lung ADC and can help stratify risk of recurrence by extent and type of resection.

Long-term survival outcome after lobectomy in patients with clinical T1 N0 lung cancer

OBJECTIVE

The aim of this study was to assess long-term outcomes after lobectomy in patients with clinical T1 N0 lung cancer based on thin-section computed tomography.

METHODS

We collected the data of patients with pathological adenocarcinoma who had undergone lobectomy. The patients were categorized into 4 groups according to a consolidation tumor ratio and tumor size. Groups A and B included tumors with consolidation tumor ratio ≤0.5 and size ≤3 cm. Group A consisted of tumors ≤2 cm. Group B consisted of the remaining tumors. Groups C and D consisted of tumors with consolidation tumor ratio >0.5. Group C consisted of those with tumors ≤2 cm and Group D consisted of tumors of size 2 to 3 cm. The 10-year overall survival and recurrence-free survival rates were examined.

RESULTS

Among the 543 patients, the 10-year overall survival was 80.4% and the 10-year recurrence-free survival rate was 77.1%. The 10-year overall survival for group A was 94.0%, 92.7% for group B, 84.1% for group C, and 68.8% for group D, and the 10-year recurrence-free survival rate for each group was 94.0%, 89.0%, 79.7%, and 66.1%, respectively. Group A + B showed better overall survival than group C + D (hazard ratio, 2.78; 95% confidence interval, 1.45-5.06) and better 10-year recurrence-free survival (hazard ratio, 2.74; 95% confidence interval, 1.55-4.88). No patient in group A had recurrence.

CONCLUSIONS

Those patients with total tumor size ≤3 cm and consolidation tumor ratio ≤0.5 showed excellent prognosis and might be suitable candidates for sublobar resection. If noninferior survival of segmentectomy compared with lobectomy is confirmed in an ongoing Japan Clinical Oncology Group trial, segmentectomy will be included in the standard of care.

Clinicopathological features of small-sized peripheral squamous cell lung cancer

Recent advances in imaging technology have enhanced the detection rate of small-sized peripheral lung cancers. The present study aimed to identify the clinicopathological differences between patients with small-sized peripheral squamous cell carcinoma (SCC) and adenocarcinoma (ADC). Patients with lung cancer who underwent radical surgical resection at Gunma University Hospital between July 2007 and October 2012 were retrospectively analyzed. Patients who exhibited small-sized peripheral tumors (pathological size, ≤2 cm) located within the outer-third of the lung field on preoperative computed tomography were enrolled in the present study. A total of 26 patients were diagnosed with SCC and 214 with ADC. The results revealed that patients with SCC exhibited higher rates of pleural invasion, vascular invasion and lymphatic invasion compared with ADC patients. Additionally, the rate of postoperative recurrence was higher in patients with SCC compared with ADC patients. Patients with ADC were subsequently into two groups: Solid ADCs (sADC) and non-solid ADCs (nsADC), which included pure ground glass nodules and part-solid ADCs. The results revealed that the incidence of pleural invasion, vascular invasion and lymphatic invasion, and the rate of postoperative recurrence in patients with sADCs were similar to those with SCC, but were also significantly higher when compared with nsADC patients. The present study concluded that patients with SCC and sADC may not be suitable candidates for sublobar resection, despite exhibiting small tumors that are located in the peripheral lung.

Advances In Research Of Spreading Through Air Spaces And The Effects On The Prognosis Of Lung Cancer

The concept of spread through air spaces (STAS) has been described as a new form of invasion in the lung in the 2015 WHO classification of Lung Tumors, namely invasion through alveolar spaces. STAS is a prognostic factor independent of growth pattern and tumor stage, and it is also an independent risk factor for unfavorable prognosis of stage I lung adenocarcinoma (ADC) and stage I lung squamous cell carcinoma (SCC). The pathological characteristics are different between ADC and SCC. STAS is not reported as routine, so setting a unified pathological reading standard, and hunting for STAS as a regular reading process is urgently advocated. We write this review to investigate the research progress of STAS and its effects on the prognosis of lung cancer.

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

Recently, the incidence of small, peripheral lung adenocarcinoma has been increasing as lung cancer screening with radiologic examination is more widely performed. Tumor size is one of the determinants of the prognostic outcome in clinically node-negative lung adenocarcinoma. Sublobar resection has been proposed as one of the minimally invasive surgical options for small-sized adenocarcinomas. Despite the lack of robust clinical trial evidence, sublobar resection has become more popular, especially in developed countries where less extensive surgery may be of benefit in a population where the age of the elderly is growing. However, high risk histologic features such as micropapillary subtype and tumor spread through air space (STAS) have been associated with a significantly higher risk of local recurrence after sublobar resection, but not after lobectomy. Surgical decision-making based on frozen section diagnosis of high risk histologic features may be useful to prevent local control failure after sublobar resection. At the present time, there is little evidence to demonstrate the diagnostic accuracy of identifying high risk histologic features on frozen section. One study has so far demonstrated that diagnostic accuracy of identifying STAS is higher than that of identifying the micropapillary subtype. Additionally, the presence of STAS has been found to be more strongly associated with local recurrence in patients who had undergone sublobar resection. Although further investigation is required for validation of this finding, STAS diagnosis on frozen section may shed further light on intraoperative surgical decision-making during sublobar resection. To this end, we review the recently published data on the intraoperative identification of high risk features.

Validation of stage groupings in the eighth edition of the tumor node metastasis classification for lung adenocarcinoma

BACKGROUND

The purpose of this study was to validate stage groupings in the 8th edition of the tumor node metastasis (TNM) classification for lung adenocarcinoma and explore the non-anatomic factors that influence the prognosis of lung adenocarcinoma patients in China.

METHODS

We retrospectively analyzed the data of 291 lung adenocarcinoma patients at our department between 2008 and 2013. Logrank tests and Cox regression models were used to analyze survival among adjacent stage groupings. Kaplan-Meier curves were used to estimate overall survival (OS).

RESULTS

There were significant differences in OS in adjacent stage groupings in early stages in the 8th edition. There were also significant differences between patients treated with radical surgery and limited resection (P = 0.027). Lepidic predominant adenocarcinoma (LPA) had better survival rates than acinar predominant (APA), papillary predominant, and solid predominant with mucin production adenocarcinoma (SPA) (P = 0.008). Survival rates of micropapillary predominant adenocarcinoma were lower than the others (P = 0.003). EGFR mutations were closely associated with lepidic predominant (65%, P = 0.56) but less commonly associated with solid predominant with mucin production adenocarcinoma (24%, P = 0.02). There was no significant difference in survival between EGFR gene mutation-positive and negative groups (P = 0.402).

CONCLUSION

The 8th edition TNM may be more accurate and applicable than the 7th edition for Chinese lung adenocarcinoma patients who have undergone surgical treatment. Stage IV patients may gain survival improvement from radical surgery.

Predictive factors for invasive adenocarcinoma in patients with clinical non-invasive or minimally invasive lung cancer

Background

Pure ground glass opacity (GGO) or part-solid GGO with small solid component (≤5 mm) are likely to be non-invasive or minimally invasive lung cancer. However, those lesions sometimes are diagnosed as invasive adenocarcinoma postoperatively. The aim of this study was to determine the predictors of invasive adenocarcinoma in clinical non- or minimally invasive lung cancer.

Methods

From January 2010 to December 2017, 203 patients were diagnosed as clinical adenocarcinoma in situ (AIS) or minimally invasive adenocarcinoma (MIA) identified on chest computed tomography (CT) and they underwent surgical resection. A retrospective study was performed to analyze the prediction of invasive adenocarcinoma in clinical non- or minimally invasive lung cancer.

Results

Of all clinical AIS or MIA patients, invasive adenocarcinoma was diagnosed in 55 patients (27.1%). In clinical AIS, invasive adenocarcinoma was diagnosed in 19 patients (17.9%) and 36 patients (37.1%) were diagnosed as invasive adenocarcinoma in clinical MIA (P=0.002). Tumor diameter and the presence of solid component were confirmed to be significant predictive factors for invasive adenocarcinoma in a multivariate analysis [hazard ratio (HR) 1.071, P=0.037; HR 2.573, P=0.005; respectively].

Conclusions

Large tumor size and the presence of solid component in clinical AIS or MIA are predictive factors for invasive adenocarcinoma. Therefore, early surgical intervention is recommended for those lesions.

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.

Prophylactic air-extraction strategy after thoracoscopic wedge resection

Background

Since the conception of enhanced recovery after surgery protocols, tubeless strategies have become popular. Herein, we introduce a previously unreported alternative air‐extraction strategy for patients who have undergone thoracoscopic wedge resection and explore its feasibility and safety.

Methods

Between January 2015 and June 2017, 264 consecutive patients underwent thoracoscopic wedge resection with different drainage strategies. Patients were divided according to the postoperative drainage strategies used: routine chest tube drainage (RT group), complete omission of chest tube drainage (OT group), and prophylactic air‐extraction catheter insertion procedure (PC group). Using the propensity score matching method, clinical parameters and objective operative qualities were compared among the three groups.

Results

Optimal 1:1 matching was used to form pairs of RT (n =36) and PC (n =36) groups and balance baseline characteristics among the three groups. The incidence rates of pneumothorax were 5.6% (2/36), 9.8% (5/51), and 19.4% (7/36) in the RT, OT, and PC groups, respectively (P = 0.07). Chest tube reinsertion incidence for postoperative pneumothorax was 19.4% (1/7) in the PC group and 60% (3/5) in the OT group. Other postoperative complications were comparable among these groups.

Conclusions

The prophylactic air‐extraction strategy may be an alternative procedure for selected patients. Remedial air extraction may reduce the occurrence of chest tube reinsertion for pneumothorax patients, but further investigation is required.

Risk Factors of Recurrence in Patients With Clinical Stage IA Adenocarcinoma Presented as Ground-Glass Nodule

BACKGROUND

In this study we aimed to identify the risk factors of recurrence in patients with clinical stage IA adenocarcinoma presented as ground glass nodule (GGN) on computed tomography scans.

PATIENTS AND METHODS

The study included 245 patients with clinical stage IA adenocarcinoma presented as GGN who underwent surgery during 2010 to 2013. All patients were divided into 2 subgroups on the basis of consolidation diameter to tumor diameter (C/T) ratio on lung window: (1) ground-glass opacity (GGO)-dominant subgroup (C/T ≤ 0.5; n = 179); (2) solid-dominant subgroup (C/T > 0.5; n = 66). Recurrence-free survival (RFS) was analyzed to identify independent risk factors of recurrence using the Kaplan-Meier approach and multivariable Cox models.

RESULTS

Patients in the GGO-dominant subgroup had a better prognosis than those in the solid-dominant subgroup (5-year RFS: 98% vs. 87%; P < .001). Multivariate analysis confirmed that C/T ratio was an independent risk factor for RFS in patients with clinical stage IA adenocarcinoma presented as GGN (hazard ratio [HR], 9.47; 95% confidence interval [CI], 1.75-51.1; P = .009). In the analysis of the solid-dominant group, multivariate analysis showed that limited resection was an independent risk factor of recurrence in this subgroup (HR, 6.86; 95% CI, 1.50-31.42; P = .013). Regarding the GGO-dominant subgroup, surgical type was not a risk factor of recurrence.

CONCLUSION

Patients with clinical stage IA solid-dominant adenocarcinoma (C/T ratio > 0.5) had a higher rate of recurrence after limited resection than lobectomy. Thus, limited resection should be performed cautiously in these patients (C/T ratio > 0.5).

Prognostic prediction of clinical stage IA lung cancer presenting as a pure solid nodule

Background

Clinical stage IA lung cancer presenting as a ground glass opacity (GGO) on imaging is known to be associated with a good prognosis. Conversely, the prognosis of lung cancer presenting as a pure solid nodule is less favorable. The purpose of this study was to identify the predictive factors affecting prognosis in pure solid nodule lung cancer.

Methods

A total of 328 consecutive patients undergoing curative resection of clinical stage IA pure solid nodule lung cancer were reviewed retrospectively. Recurrence, survival and risk factors for nodal upstaging were analyzed.

Results

Of the 328 patients, 277 patients (84.6%) underwent lobectomy (or greater) and 51 patients (15.6%) underwent sublobar resection. Mediastinal lymph node dissection or sampling was performed in 278 patients (84.8%). The 5-year recurrence-free survival rate was 70.0% and the disease-specific survival rate was 86.5%. Intraoperative mediastinal lymph node dissection was the only significant related factor for recurrence and cancer-related death in a multivariate analysis [hazard ratio (HR) =0.485, P=0.020; HR =0.342, P=0.014]. A total of 217 patients underwent lobectomy with mediastinal lymph node dissection and nodal upstaging occurred in 36 patients (16.6%). There were no significant predictive factors for nodal upstaging in a multivariate analysis. Visceral pleural invasion, lymphovascular invasion, and small cell carcinoma histology were the only identified risk factors for nodal upstaging (HR =3.858, P=0.006; HR =8.792, P<0.001; HR =45.908, P=0.017).

Conclusions

There were no definite factors predictive of prognosis in clinical stage IA pure solid nodule lung cancer. Only accurate pathologic staging and adequate intraoperative lymph node dissection were shown to be related to prognosis.

Surgical treatment for early stage non-small cell lung cancer

Surgery is the standard of care for early stage non-small cell lung cancer. There is significant debate about the type of operation most effective for lung cancer. Minimally invasive techniques like video-assisted (VATS) and robot-assisted thoracoscopic surgery (RATS) have been shown to reduce postoperative complications and shorten hospitalization. However, there remains skepticism about their oncologic effectiveness when compared to an open approach, though recent literature suggests no differences in upstaging or survival between VATS and thoracotomy. The extent of resection for early lung cancer also remains a matter of debate. Lobectomy remains the preferred operation and is associated with better survival and lower locoregional recurrence, but there is increased interest in the role of sublobar resections. Sublobar resections have similar mortality to lobar resections in small ground glass-predominant tumors. We examine the literature surrounding these controversies in this review.

Virtual-assisted lung mapping (VAL-MAP) shortened surgical time of wedge resection

Background

The detection of extremely small lung tumors has increased with the development of computed tomography. Resection of such tumors by thoracoscopy is often hindered due to the unclear location of the tumor. Various methods of preoperative determination of such lesions have been attempted, but without marked success. Here we used virtual-assisted lung mapping (VAL-MAP) to perform surgical resection of small lung lesions.

Methods

We selected patients with pulmonary tumors that we anticipated to be difficult to identify during thoracoscopy and/or decide the resection line for sub-lobar lung resection. The wedge resections in the VAL-MAP group were compared to a group of patients who underwent wedge resection without VAL-MAP in 2013.

Results

Surgery duration was significantly shorter in the VAL-MAP group (average: 76.4 min) than in the 2013 group (average: 108.6 min; P=0.000451), although the VAL-MAP group (average major axis: 9.6 mm) had smaller tumors (P=0.000032) and more pure ground-glass opacities (GGOs) (P=0.0000919) than the 2013 group (average major axis: 16.6 mm).

Conclusions

The findings of this study indicate that VAL-MAP is efficacious. In particular, VAL-MAP resulted in a shorter surgery duration and has expanded the indications of resectable lesions.

Sublobar resections for small-sized stage Ia lung adenocarcinoma: a Sino-Japanese multicenter study

Background

Segmentectomy for small-sized stage Ia non-small cell lung cancer (NSCLC) may be comparable to lobectomy regarding prognosis and local recurrence. However, the clinical results of wedge resection for such patients are still under debate. In this international multicenter study, we retrospectively studied surgical outcomes of sublobar resections for patients with small-sized stage Ia adenocarcinoma to elucidate whether wedge resection is inferior to segmentectomy for such patients.

Methods

Between March 2000 and August 2011, 173 patients underwent segmentectomy (group I), and 181 patients underwent wedge resection (group II) at three institutions in Japan and China. The tumor was defined as Ground glass opacity (GGO) type when the proportion of GGO was equal or more than 50% in HRCT, while solid type was defined as the proportion of GGO less than 50%. Clinicopathologic factors, local recurrence rate, and survival were compared.

Results

The two groups were similar in sex, comorbidity rate, and composition of Noguchi type. There was no in-hospital death. Postoperative morbidity rate of group I was significantly higher than that of group II (11.0% vs. 2.2%, P=0.016). Local recurrence rates were similar between group I (4.0%) and group II (4.4%), while no patient with GGO type tumors had local recurrence. Overall and lung cancer-specific survivals were of no significant difference between the two groups. Lung cancer-specific survival rates at 10 years were significantly better in patients with GGO type tumors than in those with solid type tumors (100% vs. 76.9%, P<0.001). In multivariate Cox regression analyses of lung cancer-specific survival of all patients, GGO type turned out to be an independent prognostic factor, while extent of resection did not have any influence.

Conclusions

Our data suggests that sublobar resection is an acceptable procedure for small lung adenocarcinomas without nodal involvement, and wedge resection may not be inferior to segmentectomy for small GGO type tumors. Our study also demonstrates that GGO type is an independent prognostic factor of disease-free survival for small-sized (diameter ≤2.0 cm) stage Ia lung adenocarcinomas.

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.

Lobectomy versus Sublobar Resection in Non-Lepidic Small-Sized Non-Small Cell Lung Cancer

Background

Recently, many surgeons have chosen sublobar resection for the curative treatment of lung tumors with ground-glass opacity, which is a hallmark of lepidic lung cancer. The purpose of this study was to evaluate the oncological results of sublobar resection for non-lepidic lung cancer in comparison with lobectomy.

Methods

We conducted a retrospective chart review of 328 patients with clinical N0 non-small cell lung cancer sized ≤2 cm who underwent curative surgical resection from January 2009 to December 2014. The patients were classified on the basis of their lesions into non-lepidic and lepidic groups. The survival rates following lobectomy and sublobar resection were compared within each of these 2 groups.

Results

The non-lepidic group contained a total of 191 patients. The 5-year recurrence-free survival rate was not significantly different between patients who received sublobar resection or lobectomy in the non-lepidic group (80.1% vs. 79.2%, p=0.822) or in the lepidic group (100% vs. 97.4%, p=0.283). Multivariate analysis indicated that only lymphatic invasion was a significant risk factor for recurrence in the non-lepidic group. Sublobar resection was not a risk factor for recurrence in the non-lepidic group.

Conclusion

The oncological outcomes of sublobar resection and lobectomy in small-sized non-small cell lung cancer did not significantly differ according to histological type.

Thoracoscopic anatomical lung segmentectomy using 3D computed tomography simulation without tumour markings for non-palpable and non-visualized small lung nodules

OBJECTIVES

Although wedge resection can be curative for small lung tumours, tumour marking is sometimes required for resection of non-palpable or visually undetectable lung nodules as a method for identification of tumours. Tumour marking sometimes fails and occasionally causes serious complications. We have performed many thoracoscopic segmentectomies using 3D computed tomography simulation for undetectable small lung tumours without any tumour markings. The aim of this study was to investigate whether thoracoscopic segmentectomy planned with 3D computed tomography simulation could precisely remove non-palpable and visually undetectable tumours.

METHODS

Between January 2012 and March 2016, 58 patients underwent thoracoscopic segmentectomy using 3D computed tomography simulation for non-palpable, visually undetectable tumours. Surgical outcomes were evaluated.

RESULTS

A total of 35, 14 and 9 patients underwent segmentectomy, subsegmentectomy and segmentectomy combined with adjacent subsegmentectomy, respectively. All tumours were correctly resected without tumour marking. The median tumour size and distance from the visceral pleura was 14 ± 5.2 mm (range 5-27 mm) and 11.6 mm (range 1-38.8 mm), respectively. Median values related to the procedures were operative time, 176 min (range 83-370 min); blood loss, 43 ml (range 0-419 ml); duration of chest tube placement, 1 day (range 1-8 days); and postoperative hospital stay, 5 days (range 3-12 days). Two cases were converted to open thoracotomy due to bleeding. Three cases required pleurodesis for pleural fistula. No recurrences occurred during the mean follow-up period of 44.4 months (range 5-53 months).

CONCLUSIONS

Thoracoscopic segmentectomy using 3D computed tomography simulation was feasible and could be performed to resect undetectable tumours with no tumour markings.

Sublobar Resection Margin Width Does Not Affect Recurrence of Clinical N0 Non-small Cell Lung Cancer Presenting as GGO-Predominant Nodule of 3 cm or Less

BACKGROUND

Sublobar resection of lung cancer may benefit patients with lung cancer presenting as ground-glass opacity (GGO) nodules. The purpose of this study was to evaluate the effect of margin width on recurrence after sublobar resection in patients with clinical N0 non-small cell lung cancer presenting as GGO-predominant nodule.

METHODS

We conducted a retrospective chart review of 91 patients treated for clinical N0 non-small cell lung cancer ≤3 cm by sublobar resection with clear resection margins. We assigned them to two groups: GGO-predominant tumor and solid-predominant tumor. Each group was subdivided into two groups according to the margin width: resection margin ≤5 mm and resection margin >5 mm. We analyzed the clinicopathological findings and survival among these four groups.

RESULTS

There was no recurrence in GGO-predominant tumors after sublobar resection. Margin width did not influence the recurrence in GGO-predominant tumors. In the cases of solid-predominant tumor, 5-year recurrence-free survival after sublobar resection according to margin width ≤5 and >5 mm was 24.2 and 79.6 %, respectively (p < 0.001). Therefore, narrow margin width (resection margin ≤5 mm) was a significant risk factor for recurrence of solid-predominant tumors (hazard ratio 3.868, 95 % confidence interval 1.177-12.714, p = 0.026).

CONCLUSIONS

The width between the tumor and resection margin does not affect the recurrence after R0 sublobar resection in patients with clinical N0 GGO-predominant lung cancer ≤3 cm. By contrast, margin width is a significant risk factor for recurrence after sublobar resection in patients with clinical N0 solid-predominant lung cancer.

[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。