A phase III randomized trial of lobectomy versus limited resection for small-sized peripheral non-small cell lung cancer (JCOG0802/WJOG4607L)

Oncological outcome of segmentectomy for early-stage non-small-cell lung cancer with invasive characteristics: a multicentre study

OBJECTIVES

Segmentectomy can provide oncologically acceptable results for small-sized non-small-cell lung cancer (NSCLC). However, in cases of NSCLC with pathological invasive characteristics such as lymphatic invasion (LY), vascular invasion (V), pleural invasion (PL) and/or lymph node metastasis, the feasibility of segmentectomy is not known.

METHODS

The patients included in the study (i) underwent lobectomy or segmentectomy for NSCLC with invasive characteristics such as LY, V, PL or pathological lymph node metastasis; (ii) presented with a node-negative, solid component-predominant tumour (consolidation tumour ratio >50%) on preoperative computed tomography; (iii) had a whole-tumour size of 2 cm or less; and (iv) presented between January 2010 and December 2019 to one of the 3 institutions. Cumulative incidences of recurrence (CIRs) after segmentectomy and lobectomy were compared.

RESULTS

A total of 321 patients were included. Segmentectomy and lobectomy were performed in 80 (24.9%) and 241 (75.1%) patients, respectively. There was no significant difference in CIR between segmentectomy (5-year CIR rate, 17.2%) and lobectomy patients (5-year CIR rate, 27.8%, P = 0.135). In the propensity score-matched cohort, there was no significant difference in CIR between segmentectomy (5-year CIR rate, 19.1%) and lobectomy patients (5-year CIR rate, 19.2%; P = 0.650). In the multivariable analysis using inverse probability of treatment weighting and surgical method, segmentectomy was not a significant predictor of worse CIR (P = 0.920).

CONCLUSIONS

Segmentectomy is feasible for clinically early-stage NSCLC irrespective of the presence of LY, V, PL or lymph node metastasis.

Thoracoscopic Lobectomy Versus Sublobar Resection for pStage I Geriatric Non-Small Cell Lung Cancer

Objectives

The choice of resection method for geriatric patients with early-stage non-small cell lung cancer (NSCLC) remains contentious. This study aimed to evaluate survival and perioperative outcomes after thoracoscopic lobectomy resection (LR) or sublobar resection (SR) in patients aged ≥75 years with pathologic stage (pStage) I NSCLC.

Materials and Methods

We retrospectively examined 258 consecutive patients aged ≥75 years with pStage I NSCLC who underwent thoracoscopic tumor resection at our institute from 2011 to 2018. Propensity score matching (PSM) analysis identified 60 patients in each group for comparison of survival-related parameters, including disease-free survival (DFS), lung cancer-specific overall survival (OS), and non-lung cancer-specific OS, using the Kaplan-Meier analysis.

Results

LR and SR were performed in 84 (32.6%) and 174 (67.4%) patients aged ≥75 years, respectively. The LR group had younger patients, better performance status, larger tumor sizes, and deeper tumor location than the SR group. Multivariate studies showed that the resection method was not a prognostic factor for OS. The two PSM-matched groups were not significantly different with respect to lung cancer-specific OS (p = 0.116), non-lung cancer-specific OS (p = 0.408), and DFS (p = 0.597). SR helped achieve better perioperative outcomes than LR, including fewer postoperative complications (10.0% vs. 28.3%, p = 0.011), shorter operative times (p < 0.001), decreased blood loss (p = 0.026), and shorter chest tube duration (p = 0.010) and hospital stays (p = 0.035).

Conclusions

Thoracoscopic SR may provide similar oncological outcomes to LR, but may be a safer and more feasible surgical method for geriatric patients with pStage I NSCLC.

Latest Clinical Evidence and Operative Strategy for Small-Sized Lung Cancers

Many thoracic surgeons revealed that consolidation tumor ratio or solid component size on thin-section computed tomography has been considered more prognostic than maximum tumor size in non-small cell lung cancer (NCSLC). According to the results, the 8th TNM classification drastically changed the staging system, i.e., clinical T category was determined based on the invasive or solid component size excluding a ground-glass opacity (GGO). However, several debates are arising over the application of radiological solid size for the clinical T staging. Meanwhile, recent several institutional reports have noticed a significantly simple fact that the presence of a GGO denotes an influence on the favorable prognosis of NSCLC. More important, radiologic pure-solid lung cancers without a GGO exhibit more malignant behaviors with regard to both the clinical and pathological aspects, and show several histologic types that have a poorer prognosis than radiologic part-solid lung cancer. In contrast, favorable prognostic impact of the presence of a GGO component was demonstrated, which was irrespective of the solid component size in cases in which the tumor showed a GGO component. Recently, this concept has been gradually noticed on a nationwide level. Obvious distinctions regarding the several baseline characteristics between the tumor with/without GGO component is a fundamental biological feature of early-stage lung cancer, which would result in a big difference in prognosis, modes of recurrence, overall behavior, and appropriate operative strategies. As a future perspective, the presence or absence of a GGO should be considered as an important parameter in the next clinical T classification.

Prediction of lymph node metastasis of clinical stage IA non-small cell lung cancer based on the tumor volume doubling time

PURPOSE

To investigate whether the volume doubling time is a preoperative predictor of lymph node metastasis of clinical stage IA non-small cell lung cancer (NSCLC).

METHODS

The subjects of this retrospective study were 204 patients who underwent lobectomy and mediastinal lymph node dissection for clinical stage IA NSCLC. We analyzed the relationship between lymph node metastasis and clinicopathological factors, including the volume doubling time.

RESULTS

Lymph node metastasis developed in 24 (11.8%) patients. Multivariable analysis identified consolidation diameter (Odds ratio = 1.407; 95% confidence interval, 1.007-1.966, p = 0.046) and the solid-part tumor volume doubling time (Odds ratio = 0.982; 95% confidence interval, 0.973-0.991, p < 0.001) as independent predictors of lymph node metastasis. The combination of a larger consolidation diameter (> 1.9 cm) and a shorter solid-part tumor volume doubling time (< 132 days) had sensitivity, specificity, and accuracy of 79.2%, 94.4%, and 92.6%, respectively.

CONCLUSIONS

The consolidation diameter and solid-part tumor volume doubling time can be useful preoperative predictors of lymph node metastasis of clinical stage IA NSCLC.

[Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function]

Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function Abstract. The golden standard for the therapy of early stage non-small cell lung cancer consists of surgical resection, usually performed as lobectomy or segmentectomy. These procedures demand a certain operability, including certain lung functional reserves. Patients with COPD and emphysema usually have lung function values far below that. Nevertheless, these patients can be offered treatmentif at the same time they qualify for concomitant lung volume reduction surgery (LVRS). LVRS with simultaneous tumor resection can consolidate the diagnosis, provide definite histology, correct staging, and thorough tumor resection might even improve the postoperative lung function. As with all patients with a (possible) diagnosis of cancer, the indication must be discussed in an interdiscplinary tumor board.

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.

Which will carry more weight when CTR > 0.5, solid component size, CTR, tumor size or SUVmax?

BACKGROUND

This study was conducted to explore the clinical significance of the maximum standard uptake value (SUVmax) in the clinical stage IA lung adenocarcinoma with tumor size ≤ 2 cm and consolidation to tumor ratio (CTR) > 0.5.

METHODS

We retrospectively reviewed non-small cell lung cancer patients who underwent surgeries between January 2014 and March 2017. Clinical stage IA lung adenocarcinoma patients with tumor of size ≤ 2 cm and CTR > 0.5 were enrolled. The patients were divided into two groups: part-solid and pure-solid based on whether CTR = 1.0 or not. Nodules with any amount of solid or micropapillary components were regarded as the high-risk subtype. Time-dependent ROC curve was used to determine the best cut-off value. Finally, we analyzed the relationship between SUVmax, high-risk subtypes, node metastasis and 5-year relapse-free survival and overall survival.

RESULTS

Totally, 270 patients were included. The distribution of pathological subtypes (p < 0.001), SUVmax (p < 0.001), and pathological N stage (p < 0.001) were different between the two groups. Multivariable analysis indicated that SUVmax could predict high-risk subtypes in cases of part-solid nodules (p < 0.001) and both high-risk subtypes (p = 0.022) and node metastasis (p < 0.001) in cases of pure-solid ones. SUVmax ≥ 2.6 and SUVmax ≥ 5.1 were strongly associated with 5-year relapse-free survival (p < 0.001) and 5-year overall survival (p < 0.001) among all the patients, respectively.

CONCLUSION

Part-solid nodules with 0.5 < CTR < 1 and pure-solid nodules in lung adenocarcinoma show different clinicopathological characteristics, especially in SUVmax. SUVmax is significantly associated with high-risk subtypes, node metastasis, 5-year relapse-free survival and overall survival.

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.

Early Postoperative Patient-Reported Outcomes After Thoracoscopic Segmentectomy Versus Lobectomy for Small-Sized Peripheral Non-small-cell Lung Cancer

BACKGROUND

Patient-reported outcomes are critical for obtaining valuable patient insight into different surgical treatment options with comparable clinical outcomes. This study aimed to compare early postoperative patient-reported symptoms and functioning between thoracoscopic segmentectomy and lobectomy for small-sized (≤ 2 cm) peripheral non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

This study included 110 patients who underwent thoracoscopic segmentectomy or lobectomy for peripheral NSCLC ≤ 2 cm in a multicenter prospective longitudinal study (CN-PRO-Lung 1). Symptom severity, functional status, and short-term clinical outcomes were compared between the groups. Symptom severity and functional status were measured using the MD Anderson Symptom Inventory-Lung Cancer at baseline, daily post-surgery, and weekly post-discharge for up to 4 weeks. Both the proportion of moderate-to-severe scores and mean scores on a 0-10 scale were compared between the groups.

RESULTS

Overall, 48 and 62 patients underwent thoracoscopic segmentectomy and lobectomy, respectively. No significant between-group differences were found in the severity of the top five symptoms (coughing, shortness of breath, pain, fatigue, and disturbed sleep) or in the impairment of all six function items (work, walking, general activity, enjoyment of life, mood, and relations with others) during both the 6-day postoperative hospitalization and the 4-week post-discharge (all p > 0.05). Short-term clinical outcomes of postoperative hospital stay, operative time, drainage time, postoperative in-hospital oral morphine equivalent dose, and complication rate were also comparable (all p > 0.05).

CONCLUSIONS

In patients with peripheral NSCLC ≤ 2 cm, thoracoscopic segmentectomy and lobectomy might produce comparable symptom burden and functional impairment during the early postoperative period.

Meta-analysis of Lobectomy and Sublobar Resection for Stage I Non-small Cell Lung Cancer With Spread Through Air Spaces

Surgery is the preferred treatment for early-stage non-small cell lung cancer (NSCLC). Numerous studies have shown that spread through air spaces (STAS) can predict the survival of patients with stage I NSCLC. However, for stage I NSCLC, it is not known whether sublobar resection or lobectomy should be performed if STAS is present. In the present study, we compared the survival outcomes of patients with STAS who underwent lobectomy versus those who underwent sublobar resection. A search was performed on the PubMed, Cochrane Library and EMBASE on March 6, 2021 to identify relevant studies. Predetermined criteria were utilized to screen studies. A meta-analysis was performed using hazard ratio (HR). In total, 13 studies involving 5947 patients were included in the meta-analysis. It was found that STAS was significantly correlated with worse RFS (HR = 2.58, 95% CI: 2.16-3.07) and OS (HR = 2.41, 95% CI: 1.97-2.95) in patients with stage I NSCLC. Lobectomy resulted in a longer RFS (HR = 2.59, 95% CI: 1.99-3.37) and OS (HR = 2.78, 95% CI: 1.92-4.02) than sublobar resection in stage I NSCLC patients with STAS. STAS is an independent prognostic factor in NSCLC. Lobectomy may be more effective for stage I NSCLC patients who underwent sublobar resection previously if STAS is present.

Segmentectomy versus lobectomy for solid predominant cN0 lung cancer: analysis using visual evaluation of positron emission tomography

OBJECTIVES

Prognosis after segmentectomy for early-stage non-small cell lung cancer (NSCLC) with a high consolidation tumour ratio (CTR) and [18F]-fluoro-2-deoxy-D-glucose (FDG) accumulation on positron emission tomography/computed tomography is unclear.

METHODS

Participants of this study were 465 patients who underwent lobectomy or segmentectomy for clinical N0 NSCLC presenting solid component predominant tumour (CTR >50%) with a whole size ≤3 cm. Accumulations of FDG on positron emission tomography/computed tomography scans were scored according to the Deauville criteria, a 5-point visual evaluating method (Deauville score). The correlations between Deauville score, prognosis, and procedures were analysed.

RESULTS

Characteristics of pathological invasiveness, such as lymphatic invasion (P < 0.001), vascular invasion (P < 0.001) and pleural invasion (P < 0.001), and non-adenocarcinoma histologies (P < 0.001) were more common in patients with Deauville scores of 3-5. The cumulative incidence of recurrence (CIR) was higher in patients with Deauville scores of 3-5 (P < 0.001). The CIR after lobectomy and segmentectomy did not differ significantly among patients with Deauville scores of 1 or 2 (P = 0.598) or those with Deauville scores of 3-5 (P = 0.322). In the analysis of propensity score matched cohort, the CIR after lobectomy and segmentectomy did not differ significantly between patients with Deauville scores of 1 or 2 and Deauville scores of 3-5.

CONCLUSIONS

Segmentectomy may be feasible for NSCLC with high CTR (>50%) and accumulation of FDG. This finding should be confirmed in larger prospective studies.

Survival and Treatment of Lung Cancer in Taiwan between 2010 and 2016

Background: Lung cancer is the leading cause of cancer-related death, and its incidence is still growing in Taiwan. This study investigated the prognostic factors of overall survival between 2010 and 2016 in Taiwan. Methods: Data from 2010 to 2016 was collected from the Taiwan Cancer Registry (TCR). The characteristics and overall survival of 71,334 lung cancer patients were analyzed according to the tumor, node, metastasis (TNM) 7th staging system. Univariate and multivariate analysis were performed to identify the prognostic factors. Results: The five-year overall survival (n = 71,334) was 25.0%, and the median survival was 25.3 months. The five-year overall survival of patients receiving any kind of treatment (n = 65,436; 91.7%) and surgical resection (n = 20,131; 28.2%) was 27.09% and 69.93%, respectively. The clinical staging distribution was as follows: stage IA (9208, 12.9%), stage IB (4087, 5.7%), stage IIA (1702, 2.4%), stage IIB (1454, 2.0%), stage IIIA (5309, 7.4%), stage IIIB (6316, 8.9%), stage IV (41458, 58.1%). Age, sex, Charlson comorbidity index, cell type, clinical T, clinical N, clinical M, grading and treatment strategy are independent prognostic factors in the multivariate analysis. Conclusion: The outcome for lung cancer patients was still poor. The identification of prognostic factors could facilitate in choosing treatment strategies and designing further randomized clinical trials.

Prognostic influence of a ground-glass opacity component in hypermetabolic lung adenocarcinoma

OBJECTIVES

We evaluated the oncological role of a ground-glass opacity (GGO) component in hypermetabolic lung adenocarcinoma with a high maximum standardized uptake value.

METHODS

Between 2008 and 2017, we retrospectively reviewed the data of surgically resected clinically node-negative lung adenocarcinomas with a hypermetabolic activity. Furthermore, they were classified based on the presence of GGO. The prognostic significance of a GGO in hypermetabolic tumours was evaluated using the Cox proportional-hazards model. The overall survival (OS) was estimated by the Kaplan-Meier method using a log-rank test.

RESULTS

Of the 1134 surgically resected clinically node-negative lung adenocarcinoma, 603 cases with hypermetabolic activity (maximum standardized uptake value ≥3.0 mg/dl) were evaluated. Among them, there were 120 (20%) cases in the With GGO group and 483 (80%) in the Solid group. The 5-year OS of patients with hypermetabolic lung adenocarcinoma was significantly different between the With GGO and Solid groups (83.1% vs 59.4%, P < 0.001). After stratifying by the presence of GGO, maximum standardized uptake value and maximum tumour size were independently significant prognosticators in the Solid group by multivariable analysis; however, no clinical factors were associated with survival among the With GGO group. The 5-year OS was favourable despite the solid component size among the With GGO group (T1a + T1b: 85.5%, T1c: 80.0%, T2a or more: 84.2%, P = 0.904). For the Solid group, survival diminished drastically with increasing tumour size (T1a + T1b: 68.7%, T1c: 62.8%, T2a or more: 48.0%, P < 0.001).

CONCLUSIONS

The prognosis of lung adenocarcinoma with GGO was favourable even in hypermetabolic tumours. Accordingly, the presence of GGO should be considered as an important parameter in the next clinical T classification.

Surgical Extent for Ground Glass Nodules

As diagnoses of small ground glass nodule (GGN)-type lung adenocarcinoma are increasing due to the increasing frequency of computed tomography (CT) screening, surgical treatment for GGN-type lung adenocarcinoma has rapidly become more common. However, the appropriate surgical extent for these lesions remains unclear; therefore, several retrospective studies have been published and prospectively randomized controlled trials are being undertaken. This article takes a closer look at each clinical study. Convincing evidence must be published on 2 issues for sublobar resection to be accepted as a standard surgical option for GGN lung adenocarcinoma. In the absence of such evidence, it is better to perform lobar resection as long as the patient has sufficient lung function. The first issue is the definition of a sufficient resection margin, and the second is whether lymph node metastasis is conclusively ruled out before surgery. An additional issue is the need for an accurate calculation of the total size and solid size on CT. Given the results of clinical studies so far, wedge resection or segmentectomy shows a good prognosis for GGNs with a total size of 2 cm or less. Therefore, sublobar resection will play a key role even in patients who can tolerate lobectomy.

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.

Surgery without preoperative histological confirmation of lung cancer: what is the current clinical practice?

BACKGROUND

There are discordances in the guidelines regarding the need to acquire histological diagnosis before surgical treatment of (presumed) lung cancer. Preoperative histological confirmation is always encouraged in this setting to prevent unnecessary surgery or when sublobar resection for small-sized tumors is considered. The aim of this retrospective cohort study was to assess the proportion of patients undergoing lung cancer resection in the Netherlands without preoperative pathological confirmation, based on the intraoperative pathological diagnosis (IOD) rate, and to determine characteristics that may influence IOD frequency.

METHODS

Data on 10,226 patients, who underwent surgical treatment for lung cancer from 2010 to 2015, were retrieved from the Netherlands National Cancer Registry. We registered an IOD when the date of diagnosis equaled the date of the first surgical intervention. Tabulations and multivariable logistic regression were used to identify predictive parameters for IOD.

RESULTS

36% of surgical procedures were classified as IOD, and decreased with increasing tumor size and extent of surgery (57% for segmentectomy, 39% for lobectomy and 11% for pneumonectomy). IOD was more frequently observed in adenocarcinoma (41%), varied between hospitals from 13% to 66% and was less common when patients were referred from a hospital where thoracic surgery was not performed. Previous history of cancer did not affect IOD.

CONCLUSIONS

More than one-third of patients with suspected lung cancer in the Netherlands was operated without preoperative histological confirmation. There was significant variation in IOD rates between different hospitals, which deserves further detailed analysis when striving for uniform surgical quality of care for patients with lung cancer.

Segmentectomy for inner location small-sized non-small-cell lung cancer: Is it feasible?

BACKGROUND

The efficacy of segmentectomy for inner small-sized non-small-cell lung cancer (NSCLC) remains unknown. We aimed to elucidate whether segmentectomy for inner small-sized NSCLC, defined using novel three-dimensional measuring method, yields feasible oncological outcomes compared to segmentectomy for outer lesions.

METHODS

We retrospectively analyzed patients with small-sized (<2cm) cN0 NSCLC who underwent segmentectomy between January 2007 and December 2020. Tumor centrality ratio, which was measured by using three dimensional reconstruction software, was evaluated, with the location of tumor origin confirmed pathologically. Cases with a ratio below and above 2/3 were allocated to the 'Inner group' and 'Outer group', respectively. Oncological outcomes were compared between the two groups.

RESULTS

Our cohort was divided into the 'Inner group' (n=75) and 'Outer group' (n=127). The proximal distance from a tumor exceeded 20 mm in all cases. Tumor centrality ratio was associated with the pathological origin of a tumor. The rate of unforeseen positive lymph node metastasis was significantly higher in the 'Inner group' (p=0.04). There were no significant differences in the 5-year recurrence free survival (RFS; 91% versus 87%, p=0.67). Univariate analysis identified age, consolidation/tumor ratio, the presence of ground-glass-opacity (GGO) and lymphovascular invasion, but not tumor centrality, as significant prognostic factors for RFS. In the multivariate analysis, the presence of GGO and lymphovascular invasion remained significant.

CONCLUSIONS

Regarding oncological outcomes, segmentectomy with a safety proximal distance could be feasible, even for inner small-sized NSCLC. Tumor invasiveness, not tumor centrality, may influence tumor recurrence. (242 words).

Diagnosis of visceral pleural invasion using confocal laser endomicroscopy during lung cancer surgery

Background

Visceral pleural invasion (VPI) in lung cancer is a significant prognostic factor; however, it is difficult to diagnose preoperatively or intraoperatively. In this study, we examined the possibility of intraoperative diagnosis of VPI using confocal laser endomicroscopy (CLE).

Methods

Among patients with primary lung cancer who underwent surgery between April 2018 and August 2019, those in whom the tumor was in contact with the pleura on chest computed tomography and whose pleural changes were intraoperatively confirmed were enrolled in this study. In the 35 patients who underwent lung resection (6 cases with visceral pleural infiltration), the area where pleural change was noted was observed and a short video was recorded using CLE. Based on the video images, three evaluators determined the defect ratio (0%, 25%, 50%, 75%, and 100%) of the autofluorescence-positive structure. The area under the receiver operating characteristic curve was used to evaluate the diagnostic performance for VPI. In 15 cases (3 cases with VPI), a validation study was performed for intraoperative VPI according to the cutoff value of the defect ratio of the autofluorescence-positive structure.

Results

The areas under the receiver operating characteristic curve for the defect ratio of the autofluorescence-positive structure were 0.86–0.91 for the three readers. Using defect ratio of autofluorescence-positive structure cutoff of ≥50% as predictor of VPI, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 83.3–100.0%, 57.7–73.1%, 35.3–41.7%, 95.0–100.0%, and 75.0–78.1%, respectively, for the three readers. In the validation study, the sensitivity was 100%, the specificity was 83.3%, and the diagnostic accuracy rate was 86.7%.

Conclusions

The diagnosis of VPI through CLE is simple, non-invasive, and has high diagnostic accuracy rates. This method may be applicable for determining surgical procedures.

Learning curve for two-port video-assisted thoracoscopic surgery lung segmentectomy

 

OBJECTIVES

When lung cancer evolves from a large, centrally located mass to small, peripherally located pulmonary nodules, such as ground glass nodules, segmentectomy offers a reasonable method by which to save lung parenchyma without eliciting compromising oncological effects. To master these techniques, it is important to analyse the learning curve of surgeons. Therefore, the aim of the present study was to analyse the learning curve for two-port video-assisted thoracoscopic surgery (VATS) segmentectomy in our institution.

METHODS

We retrospectively collected data from 86 consecutive patients who underwent two-port VATS segmentectomy between June 2019 and November 2019. The operative time (OT) and estimated blood loss and other complications were analysed. The learning curve was evaluated using the OT and the cumulative sum (CUSUM) value of OTs across all cases.

RESULTS

We generated a graph of the CUSUM of OTs and found that the learning curve could be differentiated into 3 phases: phase 1, the initial learning phase (1st to 27th operation); phase 2, the increased competence phase (28th to 54th operation); and phase 3, the experienced phase (55th to 86th operation). The CUSUM value inflected at patient number 47. There were significant reductions in the OT and bleeding in phase 3 relative to phases 1 and 2. There were also significant differences in OT and estimated blood loss between the simple and complex segmentectomy procedures.

CONCLUSIONS

In conclusion, the 3 phases identified using CUSUM analysis of the OT represented characteristic stages of the learning curve for two-port VATS segmentectomy. The data indicate that, in our institution, the inflection point for the learning curve was achieved after operating on 47 cases.

Analysis of the short-term outcomes of biportal robot-assisted lobectomy

BACKGROUND

The present study aimed to assess the short-term consequences of biportal robot-assisted lobectomy, validating its safety and effectiveness.

METHODS

A retrospective analysis evaluated the clinical data and short-term results of 18 patients in the single medical group of the centre who underwent biportal robot-assisted lobectomy plus lymph node dissection from November 2020 to March 2021.

RESULTS

Lobectomy and lymph node dissection could be successfully accomplished in all 18 patients with the assistance of a biportal robot; there was no conversion to thoracotomy during the operation. There were 10 males and 8 females with their ages ranging from 37 to 73 (58.83 ± 9.07) years. The total operation time was 74-146 (105.06 ± 18.22) min. Punching time was 2-9 (5.11 ± 1.74) min. Docking time was 8-16 (11.94 ± 2.41) min. Console time was 50-104 (78.06 ± 17.40) min. Chest closing time was 8-17 (10.28 ± 2.74) min. Blood loss was 60-132 (94.11 ± 41.41) ml. The number of lymph nodes dissected was 16-30 (21.78 ± 4.13). Chest tube duration was 2-10 (4.06 ± 1.98) days. Drainage on the first day following surgery was 100-500 (337.22 ± 117.01) ml. Total drainage was 370-1100 (692.78 ± 161.01) ml. Duration of hospital stay was 4-12 (5.89 ± 1.94) days. The median 24 and 72 h visual analogue score scores were 4 (3-7) and 3 (2-5). Total cost (¥) was 51 000-85 000 (68 000 ± 10 000), respectively. There was one case of atrial fibrillation and one case of pulmonary infection. The complication rate was 11.11%. No serious complications were recorded after surgery, and no deaths occurred within 30 days post-surgery. The final pathological diagnosis revealed 10 cases of squamous cell carcinoma, 7 cases of adenocarcinoma and 1 case of benign disease.

CONCLUSION

The biportal robot-assisted lobectomy was found to be safe and effective in the treatment of lung cancer.

Validation of completion lobectomy after wedge resection for ≤20 mm non-small cell lung cancer

Background

Completion lobectomy after wedge resection is occasionally performed when final histopathology shows an unexpected primary lung cancer even though the primary lesion has already been resected. The objective of this study was to assess the necessity of completion lobectomy after wedge resection for ≤20 mm non-small cell lung cancer (NSCLC).

Methods

Between 2006 and 2016, a total of 112 patients with NSCLC underwent wedge resection in our department. After exclusions, 40 patients were analyzed. Of these, 17 patients underwent completion lobectomy and 23 patients underwent wedge resection alone. Age, sex, tumor size, histology, other malignant diseases and final surgical procedure were used as prognostic variables. Survival analyses were confirmed using the Kaplan-Meier method and log-rank test.

Results

Median follow-up was 70.4 months. No significant difference in 5-year overall survival (OS) and relapse-free survival (RFS) were seen in patients who underwent wedge resection alone compared to the completion lobectomy group (OS: 72.6% vs. 62.5%, P=0.34; RFS: 64.2% vs. 50.0%, P=0.35). Multivariate analysis identified age (>65 years old) and male sex as independent prognostic factors for OS and RFS.

Conclusions

Completion lobectomy after wedge resection did not impact OS or RFS compared with wedge resection alone in patients with ≤20 mm NSCLC. These findings suggested that selected patients may not require resection of the remaining lobe or lymph node dissection after initial wedge resection.

Lung Cancer Surgery after Neoadjuvant Immunotherapy

In early-stage lung cancer, recurrences are observed even after curative resection. Neoadjuvant immunotherapy might be a promising approach to eliminate micrometastasis and to potentially reduce recurrence rates and improve survival. Early trials have shown encouraging rates of pathologic response to neoadjuvant therapy and have demonstrated that surgery can be safely performed after neoadjuvant immunotherapy with various agents and in combination with chemo-(radio)therapy. However, whether these response rates translate into improved disease-free survival rates and overall survival rates remains to be determined by ongoing phase III studies.

Semiquantitative assessment of fluorodeoxyglucose uptake in primary tumours on dynamic PET/computed tomography for lymph node metastasis evaluation in patients with lung cancer: a prospective study

OBJECTIVE

To semiquantitatively estimate fluorine-18-fluorodeoxyglucose (FDG) uptake in primary lung cancer cells using dynamic and dual-time-point (DTP) PET/computed tomography (PET/CT) to obtain a diagnostic index for lymph node metastasis.

METHODS

Forty-five patients with lung cancer underwent dynamic and DTP PET/CT examinations. All primary lesions and lymph node metastases were evaluated pathologically. At each time phase, we assessed the maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) of the primary tumours. We investigated the relationship between semiquantitative index and the presence of lymph node metastasis for each case and for all cases satisfying indications for segmentectomy. In cases with lymph node metastasis, we assessed the SUVmax of pathologically proven metastatic lymph nodes and nonmetastatic lymph nodes in each dynamic phase for evaluating temporal change.

RESULTS

Among 45 patients, 15 had 17 lymph node metastasis. SUVmax, MTV and TLG of primary tumours at each time phase were significantly associated with lymph node metastasis (P < 0.05). In receiver operating characteristic analysis, dynamic second and third phases showed high diagnostic ability for lymph node metastasis. The temporal change in SUVmax in the dynamic phase between primary tumours and metastatic lymph nodes were significantly different (P = 0.065). The temporal change in SUVmax was significantly lower in nonmetastatic lymph nodes than in primary tumours and metastatic lymph nodes (P < 0.0001).

CONCLUSIONS

Semiquantitative assessment of FDG uptake in dynamic second and third phases and the assessment of temporal changes in SUVmax on dynamic PET/CT scans were important predictors in diagnosing lymph node metastasis.

Lymph node metastasis and predictive factors in clinical stage IA squamous cell carcinoma of the lung based on radiological findings

OBJECTIVES

We aimed to clarify the incidence of lymph node (LN) metastasis and its predictive factors in clinical stage IA squamous cell carcinoma (SqCC) based on radiological classification to provide surgical indications for segmentectomy.

METHODS

We retrospectively reviewed 192 patients with clinical stage IA SqCC who underwent complete resection with lobectomy and LN dissection at our institution between 2003 and 2019. To evaluate the incidence of LN metastasis from the perspective of indications for segmentectomy, we classified them into outer and inner groups based on the location of the tumor in the radiological findings.

RESULTS

Regarding tumor location, 123 patients had tumors in the outer location and 69 patients had tumors in the inner location. The incidence of LN metastasis was 6% in clinical stage IA SqCC, which included 6% in the outer location and 7% in the inner location (p = 0.669). In the outer location, all LN metastases were in N1 (6%); whereas in the inner location, the incidence of N1 and N2 metastasis were 6% and 1%, respectively. Only tumors sized > 2.0 cm were found to be significantly associated with LN metastasis in clinical stage IA SqCC.

CONCLUSIONS

We demonstrated that the incidence of LN metastasis in clinical stage IA SqCC was comparable to that of the previously reported clinical stage IA NSCLC. The incidence of LN metastasis in the outer location was similar to that in the inner location. Tumor size was only a significant factor affecting LN metastasis in clinical stage IA SqCC.

Anatomic resection has superior long-term survival compared with wedge resection for second primary lung cancer after prior lobectomy

OBJECTIVES

The extent of surgical resection for early-stage second primary lung cancer (SPLC) in patients with a previous lobectomy is unclear. We sought to compare anatomic lung resections (lobectomy and segmentectomy) and wedge resections for small peripheral SPLC using a population-based database.

METHODS

The Surveillance, Epidemiology and End Results database was queried for all patients with ≤2 cm peripheral SPLC diagnosed between 2004 and 2015 who underwent prior lobectomy for the first primary and surgical resection only for the SPLC. American College of Chest Physicians guidelines were used to classify SPLC. Kaplan-Meier analysis and multivariable Cox regression were used to compare overall survival.

RESULTS

A total of 356 patients met the inclusion criteria with 203 (57%) treated with wedge resection and 153 (43%) treated with anatomic resection. Significantly better median survival was observed with anatomic resection than with wedge resection using a Kaplan-Meier analysis (124 vs 63 months; P < 0.001). With multivariable Cox regression, improved long-term survival was observed for anatomic resection (hazard ratio: 0.44, confidence interval: 0.27-0.70; P = 0.001). Improvement in survival was demonstrated with wedge resection when lymph node sampling was done. Lastly, we calculated the average treatment effect on the treated with inverse probability weighting for a subgroup of patients and found that those with wedge resection and lymph node sampling had shorter long-term survival times.

CONCLUSIONS

Anatomic resections may provide better long-term survival than wedge resections for patients with early-stage peripheral SPLC after prior lobectomy. Significant improvement in survival was observed with wedge resection for SPLC when adequate lymph node dissection was performed.

Survival Outcomes of Lobectomy Versus Segmentectomy in Clinical Stage I Non-Small Cell Lung Cancer: A Meta-Analysis

INTRODUCTION

The gold standard surgical therapy for patients with clinical stage I non-small cell lung cancer (NSCLC) is lobectomy with mediastinal lymph node dissection. Meanwhile, segmentectomy has emerged as an alternative choice with the advantage of fewer postoperative complications. The acceptance of this procedure remains controversial, and conflicting results exist in the retrospective trials.

OBJECTIVES

The aim of this meta-analysis was to analyze the survival outcomes of lobectomy versus segmentectomy in clinical stage I NSCLC.

METHODS

A computerized literature search was done on published trials in PubMed, Embase, and the Cochrane Library to June 2019 to identify clinical trials. Lung cancer-specific survival (LCSS) and overall survival (OS) were measured as outcomes. Statistical analysis was performed in the Meta-analysis Revman 5.3 software.

RESULTS

A systematic literature search was conducted including seven studies. In this meta-analysis, the LCSS and OS in the lobectomy group were linked to a markedly lower trend in comparison to the segmentectomy group without significant statistical difference (P > 0.05), indicating that lobectomy confers an equivalent survival outcome compared with segmentectomy.

CONCLUSION

No significant differences were found in survival outcomes between lobectomy and segmentectomy. Further large-scale, prospective, randomized trials are needed to explore reasonable surgical treatments for early-stage lung cancer.

Segmentectomy or lobectomy for early-stage non-small-cell lung cancer: a systematic review and meta-analysis

OBJECTIVES

The role of segmentectomy in early-stage non-small-cell lung cancer (NSCLC) remains a matter of debate. We performed a meta-analysis to evaluate the oncological outcomes following segmentectomy versus lobectomy for stage I, stage IA only and stage IA <2 cm only.

METHODS

We systematically searched the literature for articles reporting on overall survival (OS), cancer-specific survival (CSS) or recurrence-free survival (RFS). The hazard ratios (HRs) were retrieved and pooled using an inverse variance-weighted approach.

RESULTS

Twenty-eight studies were included in the analysis. In stage I, segmentectomy was found to be inferior to lobectomy for all 3 outcomes with HR: 1.25 (P = 0.01) for OS, 1.59 (P = 0.02) for CSS and 1.40 (P < 0.001) for RFS. In stage IA, the differences were significant for OS and CSS, though not for RFS with HR: 1.31 (P = 0.04), 1.56 (P = 0.02) and 1.22 (P = 0.11), respectively. In stage IA <2 cm, no significant differences were found between segmentectomy and lobectomy with HR: 1.13 (P = 0.37) for OS, 1.02 (P = 0.95) for CSS and 1.24 (P = 0.11) for RFS.

CONCLUSIONS

For stages I and IA, lobectomy showed superior results whereas for tumours <2 cm, our study did not find significant differences in oncological outcomes between both groups. These results suggest that segmentectomy might be a valuable alternative to lobectomy for NSCLC in tumours <2 cm.

Prognosis of segmentectomy and lobectomy for radiologically aggressive small-sized lung cancer

OBJECTIVES

The purpose of this study was to determine the radiological characteristics of aggressive small-sized lung cancer and to compare the outcomes between segmentectomy and lobectomy in patients with these lung cancers.

METHODS

A series of 1046 patients with clinical stage IA1-IA2 lung cancer who underwent lobectomy or segmentectomy at 3 institutions was retrospectively evaluated to identify radiologically aggressive small-sized (solid tumour size ≤ 2 cm) lung cancers. Prognosis of segmentectomy was compared with that of lobectomy in 522 patients with radiologically aggressive small-sized lung cancer using propensity score matching.

RESULTS

Multivariable analysis showed that increasing consolidation-to-tumour ratio on preoperative high-resolution computed tomography (CT) (P = 0.037) and maximum standardized uptake on 18 fluoro-2-deoxyglucose positron emission tomography/CT (P = 0.029) was independently associated with worse recurrence-free survival. Based on analysis of the receiver operating characteristic curve, radiologically aggressive lung cancer was defined as a radiologically solid (consolidation-to-tumour ratio ≥ 0.8) or highly metabolic (maximum standardized uptake ≥ 2.5) tumour. Among patients with radiologically aggressive lung cancer, no significant statistical differences in 5-year recurrence-free (81% vs 90%; P = 0.33) and overall (88% vs 93%; P = 0.76) survival comparing lobectomy (n = 392) to segmentectomy (n = 130) were observed. Among 115 propensity-matched pairs, 5-year recurrence-free survival and overall survival were similar between patients who underwent lobectomy and those who underwent segmentectomy (83.3% and 88.3% vs 90.9% and 94.5%, respectively).

CONCLUSIONS

Difference in survival was not identified with segmentectomy and lobectomy in patients with radiologically aggressive small-sized lung cancer with high risk of recurrence.

Thoracoscopic Wedge Resection Versus Segmentectomy for cT1N0 Lung Adenocarcinoma

BACKGROUND

The choice between wedge resection and segmentectomy as a sublobar resection method for patients with cT1N0 lung cancer remains debatable. This study aimed to evaluate the clinical outcomes after wedge resection and segmentectomy for patients with cT1N0 lung adenocarcinoma.

METHODS

The study enrolled 1002 consecutive patients with cT1N0 lung adenocarcinoma who underwent sublobar resection at the authors' institution between 2011 and 2017. A propensity score-matching analysis was used to compared the clinical outcomes between the wedge resection and segmentectomy groups.

RESULTS

Wedge resection was performed for 810 patients (80.8%), and segmentectomy was performed for 192 patients (19.2%). Wedge resection resulted in better perioperative outcomes than segmentectomy. The multivariate analysis showed that the significant risk factors for poor disease-free survival (DFS) were elevated preoperative serum carcinoembryonic antigen levels, total tumor diameter greater than 2 cm, and a consolidation-to-tumor (C/T) ratio higher than 50%. After propensity-matching, no differences in overall survival or DFS were noted between the two matched groups. However, subgroup analysis showed that segmentectomy was associated with better DFS than wedge resection (p = 0.039) for the patients with a tumor diameter greater than 2 cm and a C/T ratio higher than 50%.

CONCLUSION

Segmentectomy is the appropriate surgical method for sublobar resection in cT1N0 lung adenocarcinoma patients with a tumor diameter greater than 2 cm and a C/T ratio higher than 50%. Wedge resection may be a safe and feasible sublobar resection method for patients with a tumor diameter of 2 cm or smaller or a C/T ratio of 50% or lower.

Survival and Recurrence Following Wedge Resection Versus Lobectomy for Early-Stage Non-Small Cell Lung Cancer

To determine if wedge resection is equivalent to lobectomy for Stage I Non-Small Cell Lung Cancer (NSCLC) and to evaluate the impact of radiologic and pathologic variables not available in large national databases. Records were reviewed from 2010-2016 for patients with pathologic Stage I NSCLC who underwent wedge resection or lobectomy. Propensity score matching was performed on pre-operative variables and patients with ≥1 lymph node removed. Clinical variables were compared. Kaplan-Meier curves and multivariable Cox proportional hazard models for 5-year overall survival (OS), disease-free (DFS), and locoregional-recurrence-free survival (LRFS) were created. A total of 1086 patients met inclusion criteria; 391 lobectomies and 695 wedge resections. Propensity score matching yielded 167 pairs of lobectomy and wedge resection patients. Complications were fewer for wedge resections than lobectomies, 19.2% for wedge resection patients vs 34.1% for lobectomy patients, p < 0.01. OS was equivalent between groups, 86.2% for lobectomy patients vs 83.4% for wedge resection patients p = 0.47. DFS was similar, 79.0% for lobectomy patients vs 72.5% for wedge resection patients p = 0.10. Overall LRFS was worse in wedge resection patients vs lobectomy patients, 82.0% vs 93.4% p < 0.01. However, in the matched wedge resection patients with a margin >10 mm the LRFS was equal to that of lobectomy patients, 86.4% for wedge resection patients vs 91.8% for lobectomy patients p = 0.140. Patients with Stage I NSCLC can experience similar OS, DFS, and LRFS with wedge resection as compared to lobectomy, when wedge resection margins are >10 mm and appropriate lymph node dissection is performed.

Should resection extent be decided by total lesion size or solid component size in ground glass opacity-containing lung adenocarcinomas?

BACKGROUND

Indication for sublobar resections in early-stage lung adenocarcinomas has been controversial. The purpose of this study was to find appropriate selection criteria for sublobar resections in ground glass opacity (GGO)-containing early-stage lung adenocarcinomas.

METHODS

We retrospectively studied 985 consecutive patients with clinical stage IA, peripheral GGO-containing lung adenocarcinomas ≤3 cm in size. According to their radiological appearance, they were divided into a pure GGO group and a part-solid nodule (PSN) group. The PSN group was further divided into a GGO-predominant subgroup and a solid-predominant subgroup. Propensity-score matching (PSM) was conducted first in PSNs with similar total lesion size and then in those with similar solid component size to eliminate potential confounders. Histological characteristics and prognosis were compared between matched patients to investigate the prognostic value of total lesion size and solid component size. Then solid component size was chosen as the selection criterion to compare the prognosis of patients receiving lobectomy or sublobar resections.

RESULTS

Comparing to PSNs, pure GGO lesions had significantly more favorable histological characteristics and prognosis, with 100% 5-year overall survival (OS), even though 33.3% of patients with pure GGO lesions >20 mm in total lesion size received sublobar resections. For 157 pairs of PSNs with similar total lesion size but different solid component size after the first PSM, the solid-predominant subgroup had significantly worse histological characteristics and prognosis than the GGO-predominant subgroup. After the second PSM, histological characteristics and prognosis were comparable between 73 pairs of PSNs with similar solid component size but different total lesion size. Multivariable analysis showed that solid component size, rather than total lesion size or consolidation-to-tumor ratio (CTR), was an independent prognostic factor. For PSNs containing solid component size ≤2 cm, relapse-free survival (RFS) was similar after sublobar resections or lobectomy (95.0% vs. 93.6%, P=0.592). The results remained similar for PSNs of total lesion size >2 cm but solid component size ≤2 cm (88.9% vs. 90.0%, P=0.893).

CONCLUSIONS

Solid component size better predicts histological characteristics and prognosis than total lesion size in early-stage GGO-containing lung adenocarcinomas. Instead of total lesion size, solid component size ≤2 cm may be a more appropriate selection criterion for sublobar resections in such patients.

Optimal margins for early stage peripheral lung adenocarcinoma resection

Background

A pathologically confirmed negative margin is required when performing sublobar resection in patients with early stage peripheral lung adenocarcinoma. However, the optimal margin distance to ensure complete tumor resection while preserving healthy lung tissue remains unknown. We aimed to establish a reliable distance range for negative margins.

Methods

A total of 52 intraoperative para-cancer tissue specimens from patients with peripheral lung adenocarcinoma with pathological tumors ≤2 cm in size were examined. Depending on the distance from the tumor edge (D), the para-cancer tissues were divided into the following five groups: D < 0.5 cm (group I); 0.5 cm ≤ D < 1.0 cm (group II); 1.0 cm ≤ D < 1.5 cm (group III); 1.5 cm ≤ D < 2.0 cm (group IV); and D ≥ 2.0 cm (group V). During pathological examination of the specimens under a microscope, the presence of atypical adenomatous hyperplasia or more severe lesions was considered unsafe, whereas the presence of normal lung tissue or benign hyperplasia was considered safe.

Results

Group V, in which the margin was the farthest from the tumor edge, was the safest. There were significant safety differences in between groups I and V (χ² = 26.217, P < 0.001). Significant safety differences also existed between groups II and V (χ² = 9.420, P < 0.005). There were no significant safety differences between group III or IV and group V (P = 0.207; P = 0.610).

Conclusions

We suggest that when performing sublobar resection in patients with early stage peripheral lung adenocarcinoma with pathological tumor sizes ≤2 cm, the resection margin distance should be ≥1 cm to ensure a negative margin.

Should sublobar resection be offered for screening-detected lung nodules?

The increasing use of low-dose CT for screening for lung cancer will inevitably identify many small, asymptomatic lung nodules and ground-glass opacities (GGOs). Current guidelines for the management of screening-detected lesions tend to advise a conservative approach based on serial imaging and intervention only if ‘suspicious’ features emerge. However, more recent developments in thoracic surgery and in the understanding of the screening-detected lesions themselves prompt some pertinent questions over this conservatism. Is CT surveillance sufficiently reliable to exclude malignancy? Is it really necessary to hold back on operative biopsy and resection given modern surgical safety and efficacy? Is the option for early surgical therapy a viable one—especially with the availability of sublobar resection today? Modern data suggests that the risk of inaction for some screening-detected lesions may be higher than expected, whereas the potential harm of surgical intervention may be substantially reduced by sublobar resection and the latest minimally invasive surgical techniques. A more pro-active approach towards offering surgery for screening-detected lesions should now be considered.

Narrative review of optimal prognostic radiological tools using computed tomography for T1N0-staged non-small cell lung cancer

Various radiological tools can predict the prognosis of non-small cell lung cancer (NSCLC). In this study, we evaluated the prognostic effect of different radiological tools such as whole tumor size (WTS), consolidation size (CS), consolidation tumor ratio (CTR), tumor disappearance ratio (TDR), mediastinal diameter (MD), and ground glass opacity (GGO) using high-resolution computed tomography (HRCT). We reviewed recent retrospective studies on the predictive effect of these radiological tools on disease-free survival (DFS) and overall survival (OS) in patients with T1N0-staged NSCLC. We searched PubMed and the British Library databases for the English literature published from January 2010 to December 2020 and generated a total of 32 publications (NSCLC, n=16; adenocarcinoma, n=16). The TNM classification version 7 was used in 18 studies, and version 8 in 14 studies. The evaluated radiological parameters were WTS, CS including T category, CTR, TDR, MD, presence of GGO, GGO ratio, and pure GGO. This review suggested that CS, MD, and the presence of GGO are optimal prognostic radiological tools for cT1N0-Staged NSCLC. CTR or TDR for part solid nodules (PSNs) is not a well-accepted prognostic factor. Further investigations are required to differentiate between benign scars and malignant components on HRCT and evaluate the prognosis of PSNs (1< CS ≤2 cm) with large WTS in the future.

Long-Term Prognosis of Patients With Resected Adenocarcinoma In Situ and Minimally Invasive Adenocarcinoma of the Lung

INTRODUCTION

The WHO classification of lung tumors defines adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) as cancers with no or limited histologic invasive components. The probability of patients with AIS or MIA being recurrence free for 5 years postoperatively has been found to be 100%. This study aimed to analyze the prognosis of patients with AIS or MIA after more than 5 postoperative years.

METHODS

We reviewed the pathologic findings of 4768 patients who underwent resection for lung cancer between 1998 and 2010. Of these, 524 patients with curative resection for AIS (207 cases, 39.5%) and MIA (317 cases, 60.5%) were included. Postoperative recurrence, survival, and development of secondary primary lung cancer (SPLC) were analyzed.

RESULTS

Of the included patients, 342 (65.3%) were of female sex, 333 (63.5%) were nonsmokers, and 229 (43.7%) underwent sublobar resection. Average pathologic total tumor diameter was 15.2 plus or minus 5.5 mm. Median postoperative follow-up period was 100 months (range: 1-237). No recurrence of lung cancer was observed for either AIS or MIA cases. Estimated 10-year postoperative disease-specific survival rates were 100% and 100% (p = 0.72), and overall survival rates were 95.3% and 97.8% (p = 0.94) for AIS and MIA cases, respectively. Estimated incidence rates of metachronous SPLC at 10 years after surgery were 5.6% and 7.7% for AIS and MIA, respectively (p = 0.45), and these were not correlated with the EGFR mutation status.

CONCLUSIONS

Although the development of metachronous SPLC should be noted, the risk of recurrence is quite low at more than 5 years after resection of AIS and MIA. This finding strengthens the clinical value of distinguishing AIS and MIA from other adenocarcinomas of the lung.

Survival of Octogenarians with Early-Stage Non-small Cell Lung Cancer is Comparable Between Wedge Resection and Lobectomy/Segmentectomy: JACS1303

BACKGROUND

Anatomic resection with lymph node dissection or sampling is the standard treatment for early non-small cell lung cancer (NSCLC), and wedge resection is an option for compromised patients. This study aimed to determine whether wedge resection can provide comparable prognoses for elderly patients with NSCLC.

METHODS

The study analyzed the clinicopathologic findings and surgical outcomes during a median follow-up period of 39.6 months for 156 patients with solid dominant (consolidation-to-tumor ratio > 0.5) small (whole tumor size ≤ 2 cm) NSCLC among 892 patients 80 years of age or older with medically operable lung cancer between April 2015 and December 2016.

RESULTS

The 3-year overall survival (OS) rates after wedge resection and after segmentectomy plus lobectomy did not differ significantly (86.5 %; 95 % confidence interval [CI], 74.6-93.0 % vs 83.7 % 95 % CI, 74.0-90.0 %; P = 0.92). Multivariable Cox regression analysis of OS with propensity scores showed that the surgical procedure was not an independent prognostic predictor (hazard ratio [HR], 0.84; 95 % CI, 0.39-1.8; P = 0.64). The 3-year OS rates were slightly better after wedge resection for 97 patients who could tolerate lobectomy than after segmentectomy plus lobectomy (89.4 %; 95 % CI, 73.8-95.9 % vs 75.8 %; 95 % CI, 62.0-85.2 %; P = 0.14). The cumulative incidence of other causes for death was marginally higher after segmentectomy plus lobectomy than after wedge resection (P = 0.079).

CONCLUSIONS

Wedge resection might be equivalent to lobectomy or segmentectomy for selected patients 80 years of age or older with early-stage NSCLC who can tolerate lobectomy.

Comparative Effectiveness of Lobectomy, Segmentectomy, and Wedge Resection for Pathological Stage I Non-small Cell Lung Cancer in Elderly Patients: A Population-Based Study

Introduction: This study was designed to assess the long-term survival of lobectomy, segmentectomy, and wedge resection for pathological stage I non-small cell lung cancer (NSCLC) in patients over 75 years of age.

Patients and methods: Pathological stage I NSCLC patients aged ≥75 years who underwent lobectomy, segmentectomy, or wedge resection were identified from the Surveillance, Epidemiology, and End Results database. Propensity score–matched and competing risks analyses were conducted. The overall survival (OS) rate and lung cancer–specific survival (LCSS) rate were compared among the three groups based on the pathological stage.

Results: A total of 3,345 patients were included. In the full cohort, the OS rate and LCSS rate of lobectomy were superior to wedge resection, but not to segmentectomy, the OS advantage diminished when patients were over 85 years old or when at least one lymph node was examined during the procedure. Stratified analyses showed that there was no significant difference in OS and LCSS rates among the three surgical procedures for patients with tumors smaller than 1.0 cm. The OS and LCSS of wedge resection, not segmentectomy, were inferior to lobectomy in stage IA2–IB tumors.

Conclusion: Lobectomy should be recognized as the “gold standard” procedure for pathological stage I NSCLC in patients over 75 years of age, and segmentectomy could be considered as an effective alternative. Wedge resection could be considered for patients with compromised cardiopulmonary function or tumors smaller than 1.0 cm, and intraoperative lymph node examination should be conducted.

A bibliometric analysis of segmentectomy versus lobectomy for non-small cell lung cancer research (1992-2019)

BACKGROUND

This study intends to create a series of scientific maps to quantitatively estimate hot spots and emerging trends in segmentectomy versus lobectomy for non-small cell lung cancer (NSCLC) research with bibliometric methods.

METHODS

Articles published on segmentectomy versus lobectomy for NSCLC were extracted from the Web of Science Core Collection (WoSCC). Extracted information was analyzed quantitatively using bibliometric analysis by CiteSpace to find hot spots and frontiers in this research area.

RESULTS

A total of 362 scientific articles on segmentectomy versus lobectomy for NSCLC were collected, and the annual publication rate increased over time from 1992 to 2019. The leading country and the leading institution were the United States and University of Pittsburgh, respectively. Furthermore, the most prolific researchers were, namely, James D. Luketich, Rodney J. Landreneau, Matthew J. Schuchert, Morihito Okada, and David O. Wilson. The analysis of keywords pointed out that carcinoma, bronchogenic carcinoma, limited resection, segmental resection, and morbidity are hot spots and lymph node dissection, minimally invasive surgery, impact, epidemiology, and high risk are research frontiers in this field.

CONCLUSION

Publications related to segmentectomy versus lobectomy for NSCLC have made great achievements based on bibliometric analysis in recent years. However, further research and global collaboration are still required. Finally, we find that segmentectomy for the treatment of NSCLC is receiving much more attention from researchers globally compared with lobectomy in this research area.

Is the size of the lepidic component negligible when measuring the size of the tumor to determine the stage of lung adenocarcinoma?

Background

After applying the 8th edition of the TNM staging system, the invasive component size, not total tumor size, began to be used as a T descriptor for the stage. The aim of this study was to evaluate whether the size of the lepidic component can be negligible when using only the invasive component size as the T descriptor.

Methods

From 2010 to 2018, 613 consecutive patients were diagnosed as having stage IA lung adenocarcinoma and underwent anatomical lobectomy at a tertiary hospital. Pathologic specimens and medical records were reviewed retrospectively. Statistical analyses were conducted to find out whether the recurrence of stage IA lung adenocarcinoma was more affected by total tumor size (including lepidic component size) or invasive component size.

Results

The 5-year recurrence-free survival (RFS) rates of stage 0, stage IA1, stage IA2, and stage IA3 were 100%, 98.4%, 89.1%, and 81.7%, respectively. In multivariate analysis, total tumor size was not a risk factor for recurrence, whereas invasive component size was a significant risk factor for recurrence (Hazard ratio =1.658, P=0.043). In subgroup analysis, 5-year RFS rates of large lung adenocarcinoma (total tumor size >3 cm) and others (total tumor size ≤3 cm) in the same invasive component size group (stage IA2 and stage IA3) were not statistically different.

Conclusions

Invasive component size was a risk factor for recurrence of stage IA lung adenocarcinoma, while total tumor size was not a risk factor. Therefore, it seems to be appropriate to ignore the size of the lepidic component.

Positron Emission Tomography in Segmentectomy for cT1N0M0 Nonsmall Cell Lung Cancer

BACKGROUND

This study was aimed to examine the significance of fluorodeoxyglucose positron emission tomography in predicting prognosis after segmentectomy in lung cancer.

METHODS

This was a retrospective cohort study, including 227 patients with cT1N0M0 nonsmall cell lung cancer who underwent positron emission tomography followed by segmentectomy between 2012 and 2019. Significance of tumor histology, T-stage, tumor size, and standardized uptake value on positron emission tomography in relation to recurrence-free survival were examined using Cox's proportional hazard analysis. Median follow-up period was 56 months (range: 1-95 months).

RESULTS

Tumor stages were Tis in 25 patients, T1mi/T1a in 51, T1b in 98, and T1c in 53. Twenty-six patients (11%) experienced recurrences, including local (n = 8) and distant (n = 18). Multivariate analysis showed that the significant variables for recurrence-free survival were T-stage and standardized uptake value (p = 0.002 and 0.015, respectively), whereas tumor histology and tumor size were not significant (p = 0.28 and 0.44, respectively). When tumor size was divided into ≤2 cm and >2 cm for analysis, it was not significant again (p = 0.49), whereas standardized uptake value remained significant (p = 0.008). While standardized uptake value of tumors with recurrences was significantly higher than those without (4.9-2.8 and 2.6-2.5, respectively, p < 0.001), there was no significant difference between local and distant recurrences (p = 0.32). Cut-off value of standardized uptake value for recurrences was 3.2. Five-year recurrence-free survival rates in tumors with standardized uptake value <3.2 and ≥3.2 were 86 and 65%, respectively (p < 0.001).

CONCLUSION

Positron emission tomography could predict the prognosis after segmentectomy better than tumor size.

Outcomes of sublobar resection vs lobectomy for invasive clinical stage T1N0 non-small-cell lung cancer: A propensity-match analysis

BACKGROUND

The role of sub lobar resection (SLR; either segmentectomy or wedge resection) vs lobectomy (LBCT) for invasive clinical stage T1N0 non-small-cell-lung-cancer (NSCLC) has not been fully established yet.

AIM

We aimed to characterize the preoperative parameters leading to selecting SLR and compare the overall survival (OS) and disease-free survival (DFS) of these two surgical approaches.

METHODS

Clinical data on 162 patients (LBCT-107; SLR-55) were prospectively entered in our departmental database. Preoperative parameters associated with the performance of SLR were identified using univariate and multivariate cox regression analysis. The Kaplan-Meier method was used to compute OS and DFS. Comparison between LBCT and SLR groups and 32 propensity-matched groups was performed using Log-rank test.

RESULTS

Median follow-up time for the LBCT and SLR groups was 4.76 (Inter-quartile range [IQR] 2.96 to 8.23) and 3.38 (IQR 2.9 to 6.19) years respectively. OS and DFS rates were similar between the two groups in the entire cohort (OS-LBCT vs SLR P = .853, DSF-LBCT vs SLR P = .653) and after propensity matching (OS-LBCT vs SLR P = .563 DSF-LBCT vs SLR P = .632). Specifically, Two- and five-year OS rates for LBCT and SLR were 90.6.% vs 92.7%, 71.8% vs 75.9% respectively. Independent predictors of selecting for SLR included older age (P < .001), reduced FEV1% (P = .026), smaller tumor size (P = .025), smaller invasive component (P = .021) and higher American Society of Anesthesiology scores (P = .014).

CONCLUSIONS

In 162 consecutive and 32 matched cases, SLR and lobar resection had similar overall and disease-free survival rates. SLR may be considered as a reasonable oncological procedure in carefully selected T1N0 NSCLC patients that present with multiple comorbidities and relatively small tumors.