Are segmentectomy and lobectomy comparable in terms of curative intent for early stage non-small cell lung cancer?

Asian Perspective on Lung Cancer Screening

Lung cancer is the leading cause of cancer-related mortality in Japan and worldwide. Early detection of lung cancer is an important strategy for decreasing mortality. Advances in diagnostic imaging have made it possible to detect lung cancer at an early stage in medical practice. Conversely, screening of asymptomatic healthy populations is recommended only when the evidence shows the benefits of regular intervention. Due to a variety of evidence and racial differences, screening methods vary from country to country. This article focused on the perspective of lung cancer screening in Japan.

Microwave ablation for the treatment of peripheral ground-glass nodule-like lung cancer: Long-term results from a multi-center study

Introduction

Microwave ablation (MWA) is an effective and safe approach for the treatment of ground-glass nodule (GGN)-like lung cancer, but long-term follow-up is warranted. Therefore, this multi-center retrospective study aimed to evaluate the results of MWA for the treatment of peripheral GGN-like lung cancer with a long-term follow-up.

Materials and Methods

From June 2013 to January 2018, a total of 87 patients (47 males and 40 females, mean age 64.6 ± 10.2 years) with 87 peripheral lung cancer lesions showing GGN (mean long axis diameter, 17 ± 5 mm) underwent computed tomography (CT)-guided percutaneous MWA. All GGN-like lung cancers were histologically verified. The primary endpoints were local progression-free survival (LPFS) and overall survival (OS). The secondary endpoints were cancer-specific survival (CSS) and complications.

Results

During a median follow-up of 65 months, both the 3-year and 5-year LPFS rates were 96.6% and 96.6%. The OS rate was 94.3% at 3 years and 84.9% at 5 years, whereas the 3-year and 5-year CSS rates were 100% and 100%, respectively. No periprocedural deaths were observed. Complications were observed in 49 patients (51.6%). Grade 3 or higher complications included pneumothorax, pleural effusion, hemorrhage, and pulmonary infection, which were identified in ten (10.5%), two (2.1%), two (2.1%), and one (1.1%) patient, respectively.

Conclusions

CT-guided percutaneous MWA is an effective, safe, and potentially curative treatment regimen for GGN-like lung cancer.

Comparison of various lung intersegmental plane identification methods

Keeping a sufficient surgical margin free of tumor is important to prevent local recurrence in lung segmentectomy. Accurate identification of the intersegmental plane is essential to achieve adequate surgical margins. Traditionally, the inflation-deflation method was used to identify the intersegmental plane. However, in recent years, various intersegmental plane identification methods, including systemic indocyanine green injection, have been reported and shown to be useful. The purpose of this review was to evaluate the identification rates, advantages, and disadvantages of various intersegmental identification methods in lung segmentectomy. There are primarily six methods: inflation-deflation method, selective segmental inflation, endobronchial dye injection, virtual-assisted lung mapping, systemic indocyanine green injection, and pure oxygen method. These are broadly classified into those that use bronchi and pulmonary arteries anatomically and those that use air and dye technically. In this review, all methods showed relatively high identification rates. Moreover, high identification rates were expected, especially with systemic indocyanine green injection and the pure oxygen method. Each method has its advantages and disadvantages as varying situations entail different methods. It is necessary to select and apply them effectively; therefore, further improvement for each method will be required in the future.

Outcome of Resected Lung Cancers with Subcentimeter Solid Component on Computed Tomography

Background Although the opportunity to treat subcentimeter lung cancers has increased, the optimal surgical methods remain unclear. We performed a retrospective study to examine the clinical outcome of subcentimeter lung cancers.

Patients and Methods In total, 118 patients who underwent curative resection for subcentimeter lung cancer from January 2005 to December 2013 were analyzed. Multivariate Cox proportional hazards models were used to calculate the hazard ratio to identify independent predictors of recurrence-free survival (RFS) and overall survival (OS).

Results Anatomical resections were performed for 64 patients (59 lobectomies and 5 segmentectomies) and wedge resections for 54 patients. Recurrence developed in six patients who had consolidation-predominant tumors (consolidation/tumor [C/T] ratio of >0.5) and underwent wedge resections. The first recurrence patterns were regional recurrences in three patients, both regional and distant in one, and distant in two. Seventeen patients died of other causes. The multivariate analysis revealed that the C/T ratio was the independent predictor of RFS (p = 0.008) and OS (p = 0.011).

Conclusion Patients with subcentimeter lung cancer rarely developed recurrence. The C/T ratio was the independent prognostic factor, and all relapsed patients received wedge resections. Even for subcentimeter lung cancers, we should select the extent of pulmonary resection after thoroughly considering whether wedge resection (less invasiveness) is a reasonable alternative to anatomical resection (superior oncologic efficacy) considering the C/T ratio of the lesion.

Development and validation of a prognostic nomogram for early stage non-small cell lung cancer: a study based on the SEER database and a Chinese cohort

Objective

This study aimed to construct a nomogram to effectively predict the overall survival (OS) of patients with early-stage non-small-cell lung cancer (NSCLC).

Methods

For the training and internal validation cohorts, a total of 26,941 patients with stage I and II NSCLC were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. A nomogram was constructed based on the risk factors affecting prognosis using a Cox proportional hazards regression model. And 505 patients were recruited from Jiaxing First Hospital for external validation. The discrimination and calibration of the nomogram were evaluated by C-index and calibration curves.

Results

A Nomogram was created after identifying independent prognostic factors using univariate and multifactorial factor analysis. The C-index of this nomogram was 0.726 (95% CI, 0.718–0.735) and 0.721 (95% CI, 0.709–0.734) in the training cohort and the internal validation cohort, respectively, and 0.758 (95% CI, 0.691–0.825) in the external validation cohort, which indicates that the model has good discrimination. Calibration curves for 1-, 3-, and 5-year OS probabilities showed good agreement between predicted and actual survival. In addition, DCA analysis showed that the net benefit of the new model was significantly higher than that of the TNM staging system.

Conclusion

We developed and validated a survival prediction model for patients with non-small cell lung cancer in the early stages. This new nomogram is superior to the traditional TNM staging system and can guide clinicians to make the best clinical decisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10067-8.

The intersegmental pulmonary vein is not always located on the intersegmental plane of the lung: Evaluation with 3-dimensional volume-rendering image reconstruction

Objective

To clarify whether intersegmental pulmonary veins are always located on the intersegmental plane and determine the division from which blood flows into them.

Methods

We analyzed representative intersegmental veins located between the upper/lingular and superior/basal division of the lungs using preoperative chest computed tomography (CT) DICOM data from 22 patients who underwent lobectomy or segmentectomy during 2020. The location and blood flow of V³a+b and V⁶b+c were assessed using REVORAS (Ziosoft), a novel volume-rendering 3-dimensional (3D) image reconstruction software dedicated to lung segmentectomy.

Results

The V³a+b was in the upper division and on the intersegmental plane between the upper and lingular divisions of the left lung in 11 patients (50%) each. A main root of V³a+b was not found in the lingular division, but some peripheral flow in the V³a+b was derived from it in 14 patients (64%). The V⁶b+c was found in the superior division of the right lower lobe in 13 patients (59%) and the left lower lobe in 10 patients (45%), and on the intersegmental plane between the superior and basal division of the right lower lobe in 6 patients (27%) and the left lower lobe in 10 patients (45%). A main root of V⁶b+c was imperceptible in the basal division. Some peripheral blood flow was derived from the basal division in 6 patients (27%) with V⁶b+c veins located in the right lower lobe and in 8 patients (36%) with V⁶b+c veins located in the left lower lobe.

Conclusions

Precise evaluation of intersegmental veins using preoperative volume-rendering 3D reconstructed CT images provides useful anatomic information for separating intersegmental pulmonary parenchyma.

The pattern of lymph node metastasis in peripheral pulmonary nodules patients and risk prediction models

Background

For peripheral pulmonary nodules, the regularity of lymph node (LN) metastasis has not been studied. This study aimed to evaluate the metastasis pattern of intrapulmonary and relevant mediastinal lymph nodes in early-stage lung cancer, and further selected patients who were of low risk of LN metastasis as potential population to receive sub-lobectomy.

Methods

This study prospectively included consecutive patients with peripheral clinical T1N0M0 disease who underwent complete resection with LN dissection or sampling from August 2014 to July 2015. The patients were followed up to 15, May 2021. Univariable or multivariable Logistic analysis was used to identify the risk factors. Models predicting LN metastasis risk were conducted. The area under the curve for the receiver operating characteristic curves was used to evaluate the diagnostic value. Disease-free survival and overall survival were compared between groups.

Results

Finally, 201 patients were included in this study. For patients with negative tumor-bearing (TB) 13 and 14 station LNs, the positive rate of other lymph node stations was extremely low. Maximum CT value, pleural indentation and CEA level were risk factors for N1 station LNs metastasis. Besides, the factors above and lobulation sign were risk factors for skip metastasis beyond TB 13 and 14 station LNs. We constructed two scoring tables to predict N1 station metastasis and skip metastasis beyond TB 13 and 14 station. The AUC were 0·837 and 0·823, respectively. Based on the first table, 40·9% of patients suffered N1 station LNs metastasis and 27·3% had N2 disease in “high risk group” while the proportion was only 5·7% and 4·5% in “low risk group”. For patients with negative TB13 and TB14 station LNs, based on the latter table, 11·1% of patients had N1 stations LNs metastasis and 16·7% had pN2 disease in “high risk group” while only 2·3% patients in “low risk group” suffered this kind of metastasis.

Conclusion

For peripheral pulmonary nodules patients, stations 13 and 14 LNs may be the sentinel nodes. For patients with low risk of N1 metastasis and skip metastasis, sub-lobar resection might be sufficient for those who were of negative TB 13 and 14 station LNs.

A novel form of precise segmentectomy-Triumphal arch-like anatomical segmentectomy

The increasingly accurate sublobar anatomical resection is constantly being explored and practiced. Surgeons try to preserve as much viable lung tissue as possible. Sublobar resection of the target tissue is similar with a cone‐shaped structure which penetrates deeply into the pulmonary parenchyma and runs through the lobe at both ends. This has not previously been described. The remaining lung tissue resembles the Triumphal Arch in Paris, France. Here, we describe triumphal arch‐like sublobectomy in detail, aiming to provide clinicians with an idea to explore this novel sublobectomy under similar conditions.

Lobectomy offers improved survival outcomes relative to segmentectomy for >2 but ≤4 cm non–small cell lung cancer tumors

Objective

The objective was to compare overall survival (OS) between lobectomy and segmentectomy for patients with non–small cell lung cancers (NSCLCs) > 2 but ≤4 cm.

Methods

The National Cancer Database was queried to identify treatment-naïve patients with NSCLC tumors >2 but ≤4 cm. Eligible patients were diagnosed with pT1 or T2 N0 M0 disease, underwent lobectomy or segmentectomy, and received no adjuvant therapy. OS was compared using the Kaplan-Meier method, and the Cox proportional-hazards model was used to identify prognostic factors for death. Propensity score matching was performed to minimize the effects of potential confounders.

Results

Included were 32,792 patients: lobectomy (n = 31,353) and segmentectomy (n = 1439). Five-year OS was improved following lobectomy over segmentectomy for patients with >2 but ≤4 cm NSCLCs (62.3% vs 52.6%; P < .0001). Further stratification demonstrated improved 5-year OS following lobectomy over segmentectomy: >2 but ≤3 cm (64.9% vs 54.3%; P < .0001) and >3 but ≤4 cm (56.9% vs 47.6%; P = .0003). In patients with a Charlson-Deyo comorbidity index of 0, 5-year OS was greater following lobectomy for >2 but ≤4 cm tumors (67.1% vs 62.1%; P = .03). Further stratification demonstrated improved 5-year OS following lobectomy for patients with Charlson-Deyo comorbidity index of 0 and > 3 but ≤4 cm tumors (61.8% vs 54.6%; P = .02). Segmentectomy was prognostic for increased risk of death in the year 1 through 5 postoperative period (hazard ratio, 1.35; P < .0001). Five-year OS remained greater following lobectomy after propensity score matching (59.6% vs 52.7%; P = .02).

Conclusions

Lobectomy is associated with superior 5-year OS compared with segmentectomy and may be preferred for NSCLC tumors >2 but ≤4 cm when feasible.

Thoracoscopic Lobectomy versus Segmentectomy in the Treatment of Patients with Early-Stage Lung Cancer

Objective

To assess the clinical efficacy of thoracoscopic lobectomy and segmentectomy in the treatment of patients with early-stage lung cancer.

Methods

A total of 70 patients with early-stage non-small cell lung cancer who were treated in our hospital from April 2018 to May 2020 were recruited and assigned at a ratio of 1 : 1 to receive either segmentectomy (observation group) or lobectomy (control group). Outcome measures included clinical efficacy, surgery-related indicators, pulmonary function indicators (forced vital capacity (FVC) and forced expiratory volume in one second (FEV1)), postoperative complications, and recurrence and metastasis.

Results

There was no significant difference in the clinical efficacy between the two groups (P > 0.05). Segmentectomy was associated with a longer operation time and shorter hospital stay compared to lobectomy (P < 0.05). There was no statistical significance in the amount of intraoperative blood loss and the number of lymph nodes dissected (P > 0.05). Segmentectomy resulted in significantly higher FVC and FEV1 levels in patients compared to lobectomy (P < 0.05). There was no significant difference in the incidence of postoperative complications between the two groups (P > 0.05). The two groups of patients were followed up for 12 months after the operation, and there was no recurrence or metastasis in either group.

Conclusion

The two surgical methods have similar efficacy and safety profiles, but for the treatment of patients with early-stage lung cancer, thoracoscopic segmentectomy is associated with a shorter hospital stay and better protection of the lung function of patients compared to lobectomy.

A Retrospective Study of Effectiveness of Thoracoscopic Lobectomy and Segmentectomy in Patients with Early-Stage Non-Small-Cell Lung Cancer

Background

Surgical treatment is the first choice for non-small-cell lung cancer. To date, there are only few studies on the changes in laboratory indexes in two types of surgery, namely, thoracoscopic lobectomy and segmental pneumonectomy.

Aim

To investigate the clinical impact of thoracoscopic lobectomy and segmentectomy in patients with early-stage non-small-cell lung cancer.

Methods

We retrospectively reviewed the medical records of 94 patients with early-stage NSCLC in our hospital from October 2017 to October 2019. The patients were divided into two groups. The patients in control and observation groups received thoracoscopic lobectomy and thoracoscopic segmentectomy, respectively. The perioperative indicators, complications, lung function, T cell subsets, tumor markers, follow-up of tumor recurrence rate, and survival rate were compared between two groups.

Results

The operation time of the observation group was longer, and the chest drainage volume was less at 24-48 h after the operation, and the chest tube indwelling time and postoperative hospital stay were shorter than those of the control group. No significant differences in complication probability were observed between two groups. The levels of FEV1, FVC, and MVV in the two groups were lower than those before the operation at 3 days after surgery, but the FEV1, FVC, and MVV levels in the observation group were higher than those in the control group. The CD3+, CD4+, and CD4+/CD8+ levels in the two groups were lower than those before the operation at 24 h and 72 h after the operation, but CD3+, CD4+, and CD4+/CD8+ levels in the observation group were higher than those of the control group.

Conclusion

Thoracoscopic lobectomy and segmental resection have similar clinical effects in the treatment of early-stage NSCLC patients, but segmental resection can preserve healthy lung tissue as much as possible, with less trauma, protect lung function, and promote postoperative recovery.

Clinical Efficacy of Different Thoracoscopic Surgeries for Patients With Non-small Cell Lung Cancer

Background

The aim of this study was to analyze the clinical efficacy of different thoracoscopic procedures in patients with non-small cell lung cancer and their correlation with matrix metalloproteinase-7 mRNA (MMPs-7 mRNA) and soluble major histocompatibility complex class I molecule A (sMICA), as well as their effect on T-cell subsets.

Methods

A total of 100 patients with non-small cell lung cancer who received different thoracoscopic surgeries were divided into the Control group (three-port thoracoscopic surgery) and the study group (single-port thoracoscopic surgery). The two groups were evaluated to compare the perioperative indicators, MMPs-7 mRNA, sMICA expression levels, T-cell subsets, postoperative pain, complication rates, and prognostic outcomes at 1-year follow-up.

Results

The operation time, blood loss, drainage tube placement time, incision length, and hospital stay in the study group were less than those in the control group (P < 0.05). There was no significant difference in the number of lymph node dissections between the two groups (P > 0.05). After 3 days, the expression levels of MMPs-7 mRNA and sMICA in the study group were lower than those in the control group (P < 0.05); CD4 +, CD8 +, and CD4 +/CD8 + in the study group were higher than those in the control group (P < 0.05). On days 1, 3, and 5, the visual analog score (VAS) of the study group was lower than that of the control group (P < 0.05); there was no significant difference in the complication rate between the two follow-up groups (P > 0.05), in which all patients completed the follow-up. After 1 year of follow-up, there was no significant difference in the tumor-free survival rate and overall survival rate between the two groups (P > 0.05).

Conclusion

Compared with three-port thoracoscopic surgery, single-port thoracoscopic surgery can improve perioperative expression, shorten hospital stay, reduce serum tumor micrometastasis levels, improve immune metastasis mechanisms and reduce pain, which is of great significance to patients with non-small cell lung cancer. It is an effective, convenient, and safe surgical option that deserves wide clinical reference.

Advances and controversies in the management of early stage non-small cell lung cancer

Complete resection continues to be the gold standard for the treatment of early-stage lung cancer. The landmark Lung Cancer Study Group trial in 1995 established lobectomy as the minimum intervention necessary for the management of early-stage non-small cell lung cancer, as it was associated with lower recurrence and metastasis rates than sublobar resection and lower postoperative morbidity and mortality than pneumonectomy. There is a growing tendency to perform sublobar resection in selected cases, as, depending on factors such as tumor size, histologic subtype, lymph node involvement, and resection margins, it can produce similar oncological results to lobectomy. Alternative treatments such as stereotactic body radiotherapy and radiofrequency ablation can also produce good outcomes in inoperable patients or patients who refuse surgery.

Overview of the outcomes of robotic segmentectomy and lobectomy

Segmentectomy has gained popularity in the latest years as a valid alternative to lobectomy. Initially reserved to patient unfit for lobar lung resection, this procedure is now offered also in selected patient with <2 cm peripheral lung cancer confined to an anatomic segment with no nodal involvement on preoperative evaluation. The introduction of screening with low-dose CT chest scan allowed the identification of lung cancer at early stages, making possible to schedule a more conservative lung surgery. A major improvement came also from minimally invasive surgery (MIS), reducing complication rate with comparable survival rates when compared to open surgery. However, due to long learning curve and uncomfortable instruments handling of video-assisted thoracoscopy, many surgeons still prefer to perform segmentectomies through a thoracotomy and thus increasing perioperative morbidity and leading to post-thoracotomy syndrome due to rib-spreading. Robotic assisted thoracic surgery (RATS) can avoid this throwback, combining the handling of open surgery with lesser invasiveness of thoracoscopy. Although literature has given strong evidences in favour of robotic lobectomies, data are still limited regarding segmentectomies performed with this technique. Moreover, no results are still available from the two ongoing randomized controlled trials comparing segmentectomy to lobectomy and so the latter represent the oncologically proper procedure for lung cancer along with lymph-node dissection. In this review we analyse the literature currently available on outcomes of lobar and sublobar anatomical resection performed by RATS, with a brief mention of the existing surgical techniques of port positioning and the costs of this procedure.

Long-Term Outcomes in Stage I Lung Cancer After Segmentectomy with a Close Resection Margin

Background

In general, a 2-cm surgical margin is recommended for limited resection to obtain equivalent oncologic outcomes to lobectomy for lung cancer. This study aimed to examine the patterns of recurrence and prognostic factors for recurrence in patients with a close parenchymal resection margin.

Methods

From January 2009 to April 2017, 156 patients with stage I lung cancer who underwent segmentectomy with a close resection margin (<2 cm) were enrolled. Recurrence-free survival and overall survival were assessed. In addition, predisposing factors for recurrence were evaluated.

Results

The mean tumor size was 1.7±0.8 cm and the parenchymal resection margin was 1.1±0.6 cm. Recurrence developed in 17 (10.7%) of the 156 patients, and the 5-year recurrence-free survival rate was 88.9%. Distant metastasis (7.7%) was the predominant recurrence pattern. The isolated local recurrence rate was 1.9%. Multivariate Cox regression analysis revealed that age, tumor size, mediastinal lymph node dissection, postoperative complications, and histologic type were significant predisposing factors for recurrence. However, parenchymal margin distance did not significantly affect the long-term prognosis.

Conclusion

Segmentectomy with a close resection margin for early-stage lung cancer in selected patients resulted in acceptable recurrence and survival. However, patients with tumors larger than 2 cm, squamous cell carcinoma histology, and insufficient mediastinal evaluation should be carefully followed up for recurrence.

Thoracoscopic complex basilar segmentectomies: an analysis of 63 procedures

Background

Thoracoscopic complex basilar segmentectomies are technically demanding and challenging. We review our experience to check whether this complexity can lead to specific surgical issues or increased post-operative morbidity.

Methods

Complex basilar segmentectomies were defined as the anatomical resection of at least one segment composing the basilar pyramid, excluding S⁶. Data of patients who had an intention-to-treat thoracoscopic complex basilar segmentectomy were retrospectively collected from 2007 to 2019: indications, preoperative assessment, clinical features, operative technical aspects and early post-operative outcome.

Results

Sixty-three patients, 26 men (41%) and 37 women (59%) with a median age of 66 years and a median body mass index (BMI) of 26 kg/m2 were included. Interventions performed were mostly S⁹⁺¹⁰ (n=32) and S⁸ (n=12) segmentectomies. Forty-five planned operations (71%) were completed. Extension to a larger resection was necessary in 17 patients (27%) and 4 patients underwent conversion to open surgery (6%). Median operative time was 168 minutes with a median intraoperative bleeding of 30 mL. Complications occurred in 11 patients (17%). There was no mortality. Median length of pleural drainage was 2 days (range, 1–2 days) and median hospital stay 4 days.

Conclusions

The extension rate of complex basilar segmentectomy is higher than that of other sublobar resections but their post-operative morbidity is identical.

Subsegmental resection preserves regional pulmonary function: A focus on thoracoscopy

Background

The aim of this study was to evaluate regional postoperative preserved pulmonary function (PPPF) and three‐dimensional (3D) volumetric changes according to the number of resected subsegments and investigate the factors that most affected pre‐/post PPPF.

Methods

Patients who underwent thoracoscopic lobectomy (n = 73), and segmentectomy (n = 87) were eligible for inclusion in the study. They were classified according to the number of resected subsegments which ranged from 1 to 10. The percentage of pre‐/postoperative forced expiratory volume in 1 s (FEV1) was used for comparison. Furthermore, lung volumetric changes were calculated using 3D computed tomography (CT) volumetry.

Results

The percentage of pre‐/postoperative EFV1 between 4 and 5–7 and between 5–7 and 10 were significant (p = 0.03 and p < 0.01, respectively), but not between 1–2 to 4 (p = 0.99). The difference between volumetric changes in the left lower lobe of patients with a number of resected subsegments was significant (p < 0.01). On univariate and multivariate analyses, chronic inflammation was significant for decrease in recovery percentages. When the PPPF was compared among resected subsegments, it gradually decreased with an increase in the number of patients without a postoperative procrastination of inflammation (p < 0.01).

Conclusions

Segmentectomy is feasible and useful for PPPF. Even a relatively large‐volume resection procedure where 5–7 subsegments are resected can preserve pulmonary function. Chronic inflammation was statistically identified as a risk factor for postoperative preserved pulmonary function.

Key points

 

Anatomical resection of lung cancer with isolated left bronchial isomerism: a case report with long-term follow-up

An isolated bronchial isomerism without accompanying malformations is known to be very rare and has little clinical problems. There are a few case reports demonstrating that the bronchial isomerism is incidentally found during lung cancer evaluations or surgeries, but none of them have reported the long-term outcomes after lung cancer surgeries. Thoracic surgeons should fully identify the anatomical details of the bronchial isomerism preoperatively to avoid unexpected resection of the wrong bronchi or pulmonary vessels. Herein, we report a rare case of an isolated left bronchial isomerism that was diagnosed preoperatively; the patient safely underwent anatomical pulmonary resection due to lung cancer in the right upper lobe and who has been followed up for >5 years.

Surgical Outcomes of Lobectomy Versus Limited Resection for Clinical Stage I Ground-Glass Opacity Lung Adenocarcinoma 2 Centimeters or Smaller

BACKGROUND

To compare the surgical outcomes of patients with clinical stage I ground-glass opacity (GGO) lung adenocarcinomas with maximum diameters of ≤ 2 cm who underwent lobectomy versus limited resection.

PATIENTS AND METHODS

We retrospectively reviewed cases of clinical stage I GGO lung adenocarcinoma with a diameter ≤ 2 cm that were treated via lobectomy or limited resection in our department between January 2011 and September 2018. The clinical characteristics and surgical outcomes were analyzed using a propensity score-matched comparison and a Cox regression model.

RESULTS

A total of 552 patients were identified; 128 patients with pure GGO were excluded. Four hundred twenty-four patients met our criteria, including 242 (57.1%) who underwent lobectomy and 182 (42.9%) who underwent limited resection. No perioperative mortality occurred in either group. The overall 5-year survival rate of the entire cohort was 88%. Patients who underwent limited resection tended to have a shorter operation time, smaller blood loss volume, fewer removed nodes, and a shorter postoperative stay. However, the groups did not differ in terms of postoperative complications. Lobectomy and limited resection could lead to equivalent overall survival in patients with GGO-dominant tumor, while lobectomy showed better overall survival than limited resection in patients with solid-dominant tumor.

CONCLUSION

Patients with small GGO lung adenocarcinoma had a favorable prognosis after surgery. The oncologic surgical procedures of lobectomy and limited resection yielded comparable outcomes in patients with clinical stage I GGO-dominant lung adenocarcinomas ≤ 2 cm, while lobectomy showed better survival than limited resection in patients with solid-dominant tumor.

Surgery or stereotactic body radiotherapy for metachronous primary lung cancer? A propensity score matching analysis

OBJECTIVE

We compared outcomes after surgery or stereotactic body radiotherapy (SBRT) among patients with metachronous primary lung cancer (MPLC).

METHODS

Patients with MPLC were treated with either surgery (2008-2018) or SBRT (2010-2018). We used propensity score matching (PSM) to reduce bias from various clinicopathological factors. MPLC was defined by the Martini and Melamed criteria.

RESULTS

Of 77 patients, 51 underwent surgery and 26 received SBRT. Most median clinicopathological characteristics did not significantly differ between the surgery and SBRT groups (male sex: 67% vs 65%; age: 73 vs 77 years; time after first surgery: 6.2 vs 4.7 years; lobectomy as first procedure: 82% vs 85%; second tumor size: 11 vs 12 mm; clinical stage I: 96% vs 100%; CEA: 2.9 vs 3.0 ng/ml). However, the surgery group had significantly more ipsilateral second tumors (n = 71, 58%, P = 0.003), better performance status (P = 0.03), and preserved lung function (P = 0.02). Surgery, thus, tended to be selected for patients with good physical function and for the MPLC in the contralateral side. Five-year overall survival did not significantly differ between the surgery and SBRT groups, either before PSM (86.5% vs 65.8%, P = 0.24, log-rank) or after PSM (100% vs 84.4%, P = 0.73).

CONCLUSIONS

Surgery and SBRT for MPLC patients are safe and feasible treatments with similar outcomes. However, this finding should be verified by a random controlled trial with a larger study cohort.

Clinicopathological features, survival outcomes, and appropriate surgical approaches for stage I acinar and papillary predominant lung adenocarcinoma

Background

Whether prognosis differs between lung acinar predominant adenocarcinoma (ACN) and papillary predominant adenocarcinoma (PAP) patients remains controversial. Furthermore, the appropriate surgical plan for each subtype is undetermined.

Methods

Data of stage I ACN or PAP patients from 2004 to 2015 were retrospectively reviewed by SEER*Stat 8.3.5. The primary outcome was overall survival (OS) and lung cancer specific survival (LCSS).

Results

1531 patients (PAP, 484; ACN, 1047) were included. ACN patients had better OS (P = .001) and LCSS (P = .003) than PAP patients. Among stage I ACN patients, lobectomy with mediastinal lymph node dissection (Lob) (P = .001) or segmentectomy (Seg) (P = .003) provided a better OS than wedge resection (Wed). And ACN patients who received Lob had a equivalent LCSS, compared to those who received Seg (P = .895). For patients with PAP in stage I, those who received Lob tended to have a better prognosis than that received Seg (HR of OS, 0.605, 95% CI: 0.263‐1.393; HR of LCSS, 0.541, 95% CI: 0.194‐1.504) or Wed (HR of OS, 0.735, 95% CI: 0.481‐1.123; HR of LCSS, 0.688, 95% CI: 0.402‐1.180).

Conclusions

Among patients with lung adenocarcinoma in stage I, those with ACN have a better OS and LCSS than that with PAP. For patients with stage I ACN, Seg and Lob, rather than Wed, seem to be an equivalent treatment choice; however, Seg is the prior option because it could preserve more lung function than Lob. For patients with PAP, Lob tends to be a better choice than Wed and Seg, although the prognostic difference between them is nonsignificant.