Small-sized Non-small Cell Lung Research Articles

ASO Author Reflections: Utility of Sublobar Resection for Small-Sized Non-Small Cell Lung Cancer.

ASO Author Reflections: Utility of Sublobar Resection for Small-Sized Non-Small Cell Lung Cancer.

Sublobar resection for small-sized non-small cell lung cancer: A comprehensive comparison between subsegmentectomy, segmentectomy and wedge resection

ObjectivesSubsegmentectomy has been adopted for non-small cell lung cancer (NSCLC) for decades. This study aimed to compare the features between subsegmentectomy, segmentectomy and wedge resection for NSCLC. Materials and methodsNSCLC patients who underwent subsegmentectomy, segmentectomy, or wedge resection between 2014 and 2019 were retrospectively screened. Demographic, radiomic, and perioperative characteristics between patients were compared. Further, log-rank test, univariate and multivariate Cox regression were used for prognostic evaluation. ResultsThere were 276, 670, and 494 patients undergoing subsegmentectomy, segmentectomy, and wedge resection, respectively. Patients with segmentectomy and subsegmentectomy had larger tumor sizes and greater distances to the pleura than those with wedge resection. Subsegmentectomy and segmentectomy were more likely to achieve adequate surgical margins than wedge resection (82.0 % vs. 79.5 % vs. 64.7 %, P < 0.001), which was especially true for nodules away from the pleura (80.2 % vs. 81.4 % vs. 55.8 %, P < 0.001). In addition, anatomic resection allowed for more lymph node dissection and required less preoperative localization than wedge reception. Subsegmentectomy preserved about two subsegments than segmentectomy (P < 0.001). The incidence of prolonged air leakage after subsegmentectomy (3.3 %) and wedge (1.8 %) was similar (P = 0.308). Notably, 66.8 % of patients who underwent segmentectomy or subsegmentectomy were considered unsuitable for wedge. During the follow-up (55.1 months), no tumor recurrence or death occurred in patients undergoing subsegmentectomy. No significant recurrence-free survival (P = 0.140) or overall survival (P = 0.370) difference existed between these groups. ConclusionsSubsegmentectomy could achieve more adequate surgical margins than wedge resection and showed superiority for deep nodules. Compared to segmentectomy, subsegmentectomy could preserve more lung parenchyma.

Comparison of early patient-reported outcomes between uniportal thoracoscopic segmentectomy and wedge resection for peripheral small-sized non-small-cell lung cancer

BackgroundAnalysis of patient-reported outcomes (PROs) offers valuable insights into distinguishing the effects of closely related medical procedures from the patient’s perspective. In this study we compared symptom burden in patients undergoing uniportal thoracoscopic segmentectomy and wedge resection for peripheral small-sized non-small cell lung cancer (NSCLC).MethodsThis study included patients with peripheral NSCLC from an ongoing longitudinal prospective cohort study (CN-PRO-Lung 3) who underwent segmentectomy or wedge resection with tumor diameter ≤ 2 cm and consolidation tumor ratio (CTR) ≤ 0.5. PROs data were collected using the Perioperative Symptom Assessment for Lung Surgery questionnaire pre-operatively, daily post-surgery up to the fourth hospitalization day, and weekly post-discharge up to the fourth week. Propensity score matching and a generalized estimation equation model were employed to compare symptom severity. In addition, short-term clinical outcomes were compared.ResultsIn total, data of 286 patients (82.4%) undergoing segmentectomy and 61 patients (17.6%) undergoing wedge resection were extracted from the cohort. No statistically significant differences were found in the proportion of moderate-to-severe symptoms and mean scores for pain, cough, shortness of breath, disturbed sleep, fatigue, drowsiness, and distress during the 4-day postoperative hospitalization or the 4-week post-discharge period before or after matching (all p > 0.05). Compared with segmentectomy, wedge resection showed better short-term clinical outcomes, including shorter operative time (p = 0.001), less intraoperative bleeding (p = 0.046), and lower total hospital costs (p = 0.002).ConclusionsThe study findings indicate that uniportal thoracoscopic segmentectomy and wedge resection exert similar early postoperative symptom burden in patients with peripheral NSCLC (tumor diameter ≤ 2 cm and CTR ≤ 0.5).Clinical trial registrationNot applicable.

ASO Visual Abstract: Three-Dimensional-Guided Cone-Shaped Segmentectomy Versus Lobectomy for Small-Sized Non-small Cell Lung Cancer in the Middle Third Lung Field.

ASO Visual Abstract: Three-Dimensional-Guided Cone-Shaped Segmentectomy Versus Lobectomy for Small-Sized Non-small Cell Lung Cancer in the Middle Third Lung Field.

The value of frozen section diagnosis of tumor spread through air spaces in small-sized (≤ 2 cm) non-small cell lung cancer

BackgroundThe current accuracy of frozen section diagnosis of tumor spread through air spaces (STAS) in non-small cell lung cancer (NSCLC) is poor. However, the accuracy and prognostic value of STAS assessment on frozen sections in small-sized NSCLC (diameter ≤ 2 cm) is unknown.MethodsThree hundred fifty-two patients with clinical stage I NSCLC (≤ 2 cm) were included, of which the paraffin sections and frozen sections were reviewed. The accuracy of STAS diagnosis in frozen sections was assessed using paraffin sections as the gold standard. The relationship between STAS on frozen sections and prognosis was assessed by the Kaplan–Meier method and log-rank tests.ResultsSTAS on frozen sections in 58 of 352 patients could not be evaluated. In the other 294 patients, 36.39% (107/294) was STAS-positive on paraffin sections and 29.59% (87/294) on frozen sections. The accuracy of frozen section diagnosis of STAS was 74.14% (218/294), sensitivity was 55.14% (59/107), specificity was 85.02% (159/187) and agreement was moderate (K = 0.418). In subgroup analysis, the Kappa values for frozen section diagnosis of STAS in the consolidation-to-tumor ratio (CTR) ≤ 0.5 group and CTR > 0.5 group were 0.368, 0.415, respectively. In survival analysis, STAS-positive frozen sections were associated with worse recurrence-free survival in the CTR > 0.5 group (P < 0.05).ConclusionsThe moderate accuracy and prognostic significance of frozen section diagnosis of STAS in clinical stage I NSCLC (≤ 2 cm in diameter; CTR > 0.5) suggests that frozen section assessment of STAS can be applied to the treatment strategy of small-sized NSCLC with CTR > 0.5.

Three-Dimensional Guided Cone-Shaped Segmentectomy Versus Lobectomy for Small-sized Non-Small Cell Lung Cancer in the Middle Third of the Lung Field.

Segmentectomy has been recommended for peripheral small-sized non-small cell lung cancer (NSCLC). This study aimed to evaluate whether three dimensionally (3D) guided cone-shaped segmentectomy can achieve long-term outcomes comparable with lobectomy for small-sized NSCLC in the middle third of the lung parenchyma. This study retrospectively screened patients with small NSCLC (≤2 cm) who underwent segmentectomy or lobectomy between January 2012 and June 2019. Tumor location was determined by 3D multiplanar reconstruction. The cone-shaped segmentectomy was performed with the guidance of 3D computed tomographic bronchography and angiography. The log-rank test, Cox hazard proportional regression, and propensity score-matching analyses were adopted for prognostic evaluation. After screening, 278 patients with segmentectomy and 174 subjects undergoing lobectomy were selected. All the patients had R0 resection, and no 30- or 90-day mortality was observed. The median follow-up time was 47.3 months. The 5-year overall survival (OS) was 99.6 %, and the disease-free survival (DFS) was 97.5 % for the patients undergoing segmentectomy. After propensity score-matching, the patients with segmentectomy (n = 112) had an OS (P = 0.530) and a DFS (P = 0.390) similar to those of the patients who underwent lobectomy (n = 112). The multivariable Cox regression analysis indicated no significant survival differences between segmentectomy and lobectomy [DFS: hazard ratio, 0.56 (95 % confidence interval (CI) 0.16-1.97, P = 0.369); OS: HR, 0.35 (95 % CI 0.06-2.06, P = 0.245)] after adjustment for other factors. Further analysis showed that segmentectomy achieved comparable OS (P = 0.540) and DFS (P = 0.930) for NSCLC in the middle-third and peripheral lung parenchyma (n = 454). For selected NSCLCs size 2 cm or smaller in the middle third of the lung field, 3D-guided cone-shaped segmentectomy was able to achieve long-term outcomes comparable with lobectomy.

ASO Author Reflections: Three-Dimensional-Guided Segmentectomy can be an Alternative to Lobectomy for Small-Sized Non-small Cell Lung Cancer in the Middle-Third Lung Parenchyma.

ASO Author Reflections: Three-Dimensional-Guided Segmentectomy can be an Alternative to Lobectomy for Small-Sized Non-small Cell Lung Cancer in the Middle-Third Lung Parenchyma.

Segmentectomy versus lobectomy for small-sized pure solid non-small cell lung cancer.

Segmentectomy has been recommended for ground glass opacity (GGO)-dominant small-sized non-small cell lung cancer (NSCLC) or those with GGO component. Pure solid NSCLC is a special sub-type and has an inferior prognosis. Whether segmentectomy could achieve comparable long-term outcomes with lobectomy for pure solid small-sized NSCLC remained controversial. This study aimed to compare the prognosis of segmentectomy and lobectomy for pure solid NSCLC. NSCLC patients with a pure solid nodule (≤2cm) who received segmentectomy or lobectomy between January 2010 and June 2019 were retrospectively screened. Log-rank test, univariable, and multivariable Cox regression analyses were used for prognostic comparison. Further, the propensity score matching analysis was adopted to yield a matched cohort. After screening, 344 pure solid NSCLC patients with a median follow-up time of 56 months were reserved. Among them, 98 patients underwent segmentectomy and the other 246 subjects received lobectomy. The lobectomy group had a larger tumor size, a higher rate of lymph node metastasis than the segmentectomy arm. Generally, patients with segmentectomy had a better disease-free survival (DFS) (p=0.011) and overall survival (OS) (p=0.028) than those with lobectomy. However, the multivariable Cox regression analysis indicated that no significant survival difference existed between segmentectomy and lobectomy after adjusting the potential confounding factors (DFS: hazard ratio [HR],0.72; 95% confidence interval [CI], 0.30-1.77, p=0.476; OS: HR,0.36; 95% CI, 0.08-1.59, p=0.178). Consistently, in the propensity score matched cohort, segmentectomy (n=74) yielded similar DFS (p=0.960) and OS (p=0.320) with lobectomy (n=74). Segmentectomy could achieve comparable oncological outcomes with lobectomy for pure solid small-sized NSCLC.

Importance of Lymph Node Evaluation in ≤2-cm Pure-Solid Non-Small Cell Lung Cancer

BackgroundThe prevalence of lymph node (LN) metastasis in small-sized lung cancer varies depending on the tumor size and proportion of ground-glass opacity. We investigated occult LN metastasis and prognosis in patients with small-sized non-small cell lung cancer (NSCLC), mainly focusing on the pure-solid tumor. MethodsWe retrospectively reviewed patients with ≤2-cm clinical N0 NSCLC who underwent lung resection with curative intent from 2003 to 2017. Among them we analyzed patients who also underwent adequate complete systematic LN dissection. Pathologic results and disease-free survival of the radiologically mixed ground-glass nodule (mGGN) and pure-solid nodule (PSN) groups were analyzed. ResultsOf 1329 patients analyzed, 591 had mGGNs and PSNs. As tumor size increased, patients in the mGGN group showed no difference in LN metastasis: ≤1 cm, 2.27%; 1.0 to 1.5 cm, 2.19%; and 1.5 to 2.0 cm, 2.18% (P = .999). However the PSN group showed a significant difference in LN metastasis as the tumor size increased: ≤1 cm, 2.67%; 1.0 to 1.5 cm, 12.46%; and 1.5 to 2.0 cm, 21.31% (P < .001). In the multivariate analysis tumor size was a significant predictor of nodal metastasis in the PSN group but not in the mGGN group. In terms of 5-year disease-free survival, the mGGN group showed a better prognosis than the PSN group (94.4% vs 71.2%, P < .001). ConclusionsWe need to conduct a thorough LN dissection during surgery for small-sized NSCLC, especially for pure-solid tumors ≥ 1 cm.

Pathologically noninvasive cancer predictors and surgical procedure for peripheral lung cancer.

In this retrospective study, based on recent studies reporting the superiority of sublobar resection to lobectomy for peripheral small size non-small cell lung cancer (NSCLC), we investigated the optimal pathological factors for predicting noninvasive cancer and the selection of operative procedure. Patients with peripheral NSCLC of ≤2cm who underwent surgery at our hospital between January 2010 and June 2020 were included in this study. We evaluated the relationship between pathologically noninvasive cancer and predictive factors according to the area under the curve (AUC) and accuracy, and the cutoff value was set to investigate indications for sublobar resection. The comparison of the AUCs revealed that the maximum standardized uptake value and consolidation to tumor (C/T) volume ratio were better predictors than the C/T ratio. Among the three factors, the C/T volume ratio showed the best accuracy. The patients were divided into two groups (low and high) using the cutoff value of the C/T volume ratio and compared according to the surgical procedure (lobectomy vs. segmentectomy). In the low-group, there was no significant difference in the prognosis. In the high-group, the 5-year recurrence-free survival rate of the patients who received lobectomy was 87.8%, while that of patients who received segmentectomy was 75.8% (p=0.08). The C/T volume ratio was the best preoperative pathologically noninvasive predictive factor. Sublobar resection should be performed with caution in cases with significant solid components on three-dimensional images.

Wedge resection plus adequate lymph nodes resection is comparable to lobectomy for small-sized non-small cell lung cancer.

The study investigated whether wedge resection plus adequate lymph nodes resection conferred comparable survival to lobectomy for node-negative non-small cell lung cancer (NSCLC) ≤2 cm. The Surveillance, Epidemiology, and End Results database was used to identify patients diagnosed with node-negative NSCLC ≤2 cm and underwent wedge resection or lobectomy (2004-2015). Patients were stratified by the procedure (wedge resection, lobectomy) and the size of NSCLC (≤1 cm, 1-2 cm). We assessed survival between patients undergoing wedge resection and lobectomy. The optimal number of lymph nodes resected which made those two procedures comparable was explored by using Kaplan-Meier analysis and Cox regression analysis. Propensity score matching was performed to minimize the effect of confounding factors. 7893 patients with lobectomy and 2536 patients with wedge resection were identified. Wedge resection was associated with worse survival either in the ≤1 cm or 1-2 cm NSCLC before and after matching. For lesions 1-2 cm and receiving lobectomy, more lymph nodes resected conferred statistically significant increase on survival and six nodes were optimal. For lesions ≤1 cm and receiving lobectomy, lymph nodes resection had no impact on survival. Wedge resection and lobectomy were comparable when one or more nodes for lesions ≤1 cm and six or more nodes for lesions 1-2 cm were resected. Wedge resection was inferior to lobectomy for NSCLC ≤1 cm and 1-2 cm. Wedge resection plus adequate lymph nodes resection was comparable to lobectomy.

Lymph node dissections and survival in sublobar resection of non-small cell lung cancer ≤ 20mm.

A randomized trial of lobectomy versus segmentectomy for small-sized (≤ 20mm) non-small cell lung cancer (NSCLC) showed that patients who had undergone segmentectomy had a significantly longer overall survival (OS) than those who had lobectomy. More attention is needed regarding the required extent of thoracic lymphadenectomy in patients with small-sized NSCLC who undergo sublobar resection. The National Cancer Database was queried for patients with clinically node-negative NSCLC ≤ 20mm who had undergone sublobar resection between 2004 and 2017. OS of NSCLC patients by the number of lymph node dissections (LNDs) was analyzed using log-rank tests and Cox proportional hazards model. The cutoff value of the LNDs was set to 10 according to the Commission on Cancer's recommendation. This study included 4379 segmentectomy and 23,138 wedge resection cases. The sequential improvement in the HRs by the number of LNDs was evident, and the HR was the lowest if the number of LNDs exceeded 10. Patients with ≤ 9 LNDs had a significantly shorter OS than those with ≥ 10 LNDs (hazard ratio [HR] 1.50, 95% confidence interval [CI] 1.40-1.61, P < 0.0001). Multivariable analysis revealed that performing ≤ 9 LNDs was an independent factor for predicting OS (HR for death: 1.34, 95% CI 1.24-1.44, P < 0.0001). These results remained significant in subgroup analyses by the type of sublobar resection (segmentectomy, wedge resection). Performing ≥ 10 LNDs has a prognostic role in patients with small-sized NSCLC even if the resection is sublobar.

Lymph node dissections and survival in sublobar resection of non-small cell lung cancer ≤ 20 mm.

e20583 Background: A recent Japanese phase III randomized trial of lobectomy versus segmentectomy for small-sized (≤ 20 mm) peripheral non-small cell lung cancer (NSCLC) (JCOG 0802) showed that patients who had undergone segmentectomy had a significantly longer overall survival (OS) in comparison with those who had lobectomy. More attention is needed regarding the required extent of thoracic lymphadenectomy in patients with small-sized NSCLC who undergo sublobar resection. Methods: The National Cancer Database was queried for patients with clinically node-negative NSCLC ≤ 20 mm who had undergone sublobar resection between 2004 and 2017. OS of NSCLC patients by the number of lymph node dissections (LNDs) was analyzed using Log-rank tests and Cox proportional hazards model. The cut-off value of the LNDs was set to 10 according to the Commission on Cancer’s recommendation. Results: This study included 4,379 segmentectomy and 23,138 wedge resection cases. The sequential improvement in the HRs by the number of LNDs was evident, and the HR was the lowest if the number of LNDs exceeded 10. Patients with ≤ 9 LNDs had a significantly shorter OS than those with ≥ 10 LNDs (hazard ratio [HR]: 1.50, 95% confidence interval [CI]: 1.40–1.61, P &lt; 0.0001). Multivariable analysis revealed that performing ≤ 9 LNDs was an independent factor for predicting OS (HR for death: 1.34, 95% CI: 1.24–1.44, P &lt; 0.0001). These results remained significant in subgroup analyses by the type of sublobar resection (segmentectomy, wedge resection). Conclusions: Performing ≥ 10 LNDs has a prognostic role in patients with small-sized NSCLC even if the resection is sublobar.

Initial treatment of early-stage small-sized non-small cell lung cancer for octogenarians: a population-based study.

The objectives of this study is to figure out the appropriate initial treatment and criteria for clinical decision for early-stage small-sized non-small cell lung cancer (NSCLC) among octogenarians. Elderly patients (≥80years) with stage I NSCLC (<3cm) were identified between 2004 and 2015 in the Surveillance, Epidemiology, and End Results database. Patients were divided into four cohorts regarding treatment modalities, and overall survival and cancer-specific survival were evaluated via Kaplan-Meier analysis and Cox proportional hazard model. The propensity score matching method was introduced in the subgroup analysis stratified by four clinical characteristics to identify the preferable treatment. A total of 7861 patients were included with a median overall survival of 43months (range 1-155months). In younger patients (80-85years), lobectomy was superior in improving the survival (versus segmentectomy, HR = 0.68, 95%CI 0.55-0.84; versus wedge resection, HR = 0.77; 95%CI 0.67-0.88). While in those over 85years, lobectomy was superior to wedge resection (HR = 0.72; 95%CI 0.53-0.98), and all other treatments were comparable. As stratified by T stage in those over 85years, lobectomy was superior to wedge resection (P = 0.023) for T1 disease, and the four treatments were all comparable in overall survival for T2 disease. In conclusions, the favored treatment of early stage NSCLC for octogenarians may be evaluated by age and T stage. Lobectomy might be preferred in patients between 80 and 85years whenever possible. Among those over 85years, radiotherapy might lead to a comparable prognosis and could be recommended as the prior treatment, while should surgery be recommended, lobectomy might be preferred for T1 disease and wedge resection for T2 disease.

Treatment Modality for Stage IB Peripheral Non-Small Cell Lung Cancer With Visceral Pleural Invasion and ≤3 cm in Size.

PurposeTo compare the survival difference among lobectomy, segmentectomy, and wedge resection and investigate the role of adjuvant chemotherapy for early-stage small-sized non-small cell lung cancer (NSCLC) with visceral pleural invasion (VPI).MethodsPatients diagnosed with stage IB peripheral NSCLC with VPI and ≤3 cm in size in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were included, and the pleural layer (PL) invasion status was identified to recognize the tumors with VPI, including PL1 and PL2. We conducted Cox proportional hazards model in multivariable analysis and subgroup analysis via propensity score matching (PSM) method and Cox regression method to figure out the optimal therapy for these patients.ResultsA total of 1,993 patients were included, all of whom received surgery, and the median follow-up was 33 months (range, 1–83 months). In multivariable analysis, age, gender, histology, pathological grade, lymph node examination, surgical approaches, and radiotherapy were independent prognostic factors for overall survival (OS). Lobectomy was superior to sublobar resection [hazard ratio (HR) = 1.41; 95% CI, 1.08–1.83], and wedge resection was associated with impaired survival compared to lobectomy (HR = 1.64; 95% CI, 1.22–2.20) in PSM analyses. In subgroup analysis, lobectomy was superior to sublobar resection among those aged <70 years (HR = 1.81; 95% CI, 1.13–2.90), female (HR = 1.75; 95% CI, 1.21–2.53), and 1–20 mm in size (HR = 1.61; 95% CI, 1.11–2.33). No survival benefit was observed for adjuvant chemotherapy.ConclusionsLobectomy was superior to wedge resection and comparable with segmentectomy for stage IB NSCLC (≤3 cm) with VPI, and adjuvant chemotherapy could not benefit these patients, even in those with sublobar resection. The preferred surgical procedure remains to be studied in prospective controlled trials.

Segmentectomy versus wedge resection for radiological solid predominant and low metabolic non-small cell lung cancer.

OBJECTIVESThe prognosis of segmentectomy and wedge resection for solid predominant early-stage non-small cell lung cancer with low metabolic activity is unclear.METHODSThis study aimed to assess patients who underwent segmentectomy or wedge resection with curative intent for clinically node-negative non-small cell lung cancer presenting as a solid predominant tumour (consolidation tumour ratio >50%) with a whole size ≤3 cm and [18F]-fluoro-2-deoxy-D-glucose accumulation weaker than that of the mediastinum tissue (Deauville score, 1 or 2) on positron emission tomography/computed tomography. The cumulative incidence of recurrence (CIR) was compared using the Gray method, and the predictive factor of CIR was analysed using the Fine and Gray method.RESULTSOf 140 patients included in this study, 93 (66.4%) underwent segmentectomy and 47 (33.6%) underwent wedge resection. No significant difference in the clinical stage was found between the 2 groups. The CIR was higher with wedge resection than with segmentectomy (P = 0.004). Recurrence after wedge resection was noted in 4 (8.5%) patients, 2 of whom had a recurrent site containing lung parenchyma of the preserved lobe and hilum lymph node, which would have been resected if segmentectomy had been performed. In the multivariable analysis for CIR using inverse probability of treatment weighting and the procedure, wedge resection was a significantly worse predictive factor (hazard ratio, 12.280; P = 0.025).CONCLUSIONSSegmentectomy rather than wedge resection should be considered for solid predominant, small-size non-small cell lung cancer even if [18F]-fluoro-2-deoxy-D-glucose accumulation is low.

ASO Visual Abstract: Early Postoperative Patient-Reported Outcomes After Thoracoscopic Segmentectomy Versus Lobectomy for Small-Sized Peripheral Non-small Cell Lung Cancer

ASO Visual Abstract: Early Postoperative Patient-Reported Outcomes After Thoracoscopic Segmentectomy Versus Lobectomy for Small-Sized Peripheral Non-small Cell Lung Cancer

Segmentectomy for Inner Location Small-Sized Non-Small Cell Lung Cancer: Is It Feasible?

BackgroundThe 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 a novel 3-dimensional measuring method, yields feasible oncologic outcomes compared with segmentectomy for outer lesions. MethodsWe retrospectively analyzed patients with small-sized (<2 cm) cN0 NSCLC who underwent segmentectomy between January 2007 and December 2020. The tumor centrality ratio, which was measured by using 3-dimensional reconstruction software, was evaluated. The location of tumor origin was confirmed pathologically. Cases with a ratio <2:3 and >2:3 were allocated to the inner group and outer group, respectively. Oncologic outcomes were compared between the 2 groups. ResultsOur cohort was divided into the inner group (n = 75) and outer group (n = 127). The proximal distance from a tumor was >20 mm in all cases. The tumor centrality ratio was associated with the pathologic origin of a tumor. The rate of unforeseen positive lymph node metastasis was significantly higher in the inner group (P = .04). There were no significant differences in the 5-year recurrence-free survival (91% vs 87%, P = .67). Univariate analysis identified age, consolidation/tumor ratio, the presence of ground-glass opacity, and lymphovascular invasion, but not tumor centrality, as significant prognostic factors for recurrence-free survival. In the multivariate analysis, the presence of ground-glass opacity and lymphovascular invasion remained significant. ConclusionsRegarding oncologic 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.

Feasibility of limited resection for peripheral small-sized non-small cell lung cancer: a retrospective single-center-based study.

This study aimed to establish new criteria for limited resection of non-small cell lung cancer (NSCLC) based on computed tomography findings and maximum standardized uptake value (SUVmax). Between December 2007 and December 2015, 611 patients underwent lung cancer surgery; of these, 70 with cT1aN0M0 who underwent limited resection were enrolled. Criteria for undergoing intentional limited resection (ILR) were (1) tumor ground-glass opacity (GGO) ratio of ≥ 0.75 and (2) tumor SUVmax ≤ 1.5. Patients who met criteria (1) and (2) underwent partial resection, and those who only met criteria (2) underwent segmentectomy as ILR. The control group was subjected to limited surgery without meeting the criteria. Overall, 45 and 25 patients who met the criteria were included in the ILR and control groups, respectively. In the ILR group, 13 patients underwent partial resection, and 32 underwent segmentectomy; in the control group, 18 patients underwent partial resection and 7 underwent segmentectomy. According to our criteria, no relapsed cases occurred in the ILR group, although six patients showed recurrence of lung cancer in the control group. The 5-year overall survival (OS) rates in the ILR and control groups were 100% and 67.7%, respectively, and the relapse-free survival (RFS) rates were 100% and 61.6%, respectively. The log-rank test showed that this difference was statistically significant (OS: P < 0.0001, RFS: P < 0.0001). SUVmax may serve as a predictive marker of recurrence to determine the treatment strategy for patients with NSCLC. Patients with low GGO ratio and low SUVmax may be cured by limited resection.

The prognosis of small-sized non-small cell lung cancer with visceral pleural invasion after sublobar resection.

BackgroundSublobar resection is sometimes performed as a surgical treatment for small peripheral tumors. However, there is a question about whether sublobar resection is adequate treatment when visceral pleural invasion is diagnosed postoperatively. The purpose of this study was to evaluate the prognosis of patients with small-sized stage IB non-small cell lung cancer (NSCLC) after sublobar resection.MethodsFrom January 2010 to December 2018, 227 consecutive patients with eighth edition TNM stage IB NSCLC (per the joint staging system of the International Association for the Study of Lung Cancer and the American Joint Committee on Cancer) underwent curative surgery at a single center. Those patients were reviewed retrospectively. The clinicopathological characteristics and prognosis were compared between the sublobar resection group and the lobectomy group. The sublobar resection group included only small-sized (invasive component size ≤2 cm) NSCLC.ResultsIn all study patients, clinicopathological characteristics between the sublobar resection and lobectomy groups were not different except in maximum standardized uptake value (SUVmax) and invasive component size. The 5-year recurrence-free survival (RFS) rate was 80.7% after sublobar resection and 73.4% after lobectomy (P=0.349). The 5-year overall survival (OS) rate was 87.3% after sublobar resection and 84.8% after lobectomy (P=0.503). In patients with small-sized NSCLC, the clinicopathological characteristics were not different between the sublobar resection group and the lobectomy group. The 5-year RFS rate was 80.7% after sublobar resection and 72.3% after lobectomy (P=0.417). The 5-year OS rate was 87.3% after sublobar resection and 91.2% after lobectomy (P=0.956). Sublobar resection was not a risk factor for recurrence in the multivariate analysis.ConclusionsThe prognosis of sublobar resection in patients with small-sized stage IB NSCLC was comparable with lobectomy. Thus, additional completion lobectomy may not be essential in this setting, despite postoperative upstaging from T1 to T2a.