A guide for managing patients with stage I NSCLC: deciding between lobectomy, segmentectomy, wedge, SBRT and ablation-part 2: systematic review of evidence regarding resection extent in generally healthy patients

The Proposed Ninth Edition TNM Classification of Lung Cancer

A universal nomenclature of the anatomic extent of lung cancer has been critical for individual patient care as well as research advances. As progress occurs, new details emerge that need to be included in a refined system that aligns with contemporary clinical management issues. The ninth edition TNM classification of lung cancer, which is scheduled to take effect in January 2025, addresses this need. It is based on a large international database, multidisciplinary input, and extensive statistical analyses. Key features of the ninth edition include validation of the significant changes in the T component introduced in the eighth edition, subdivision of N2 after exploration of fundamentally different ways of categorizing the N component, and further subdivision of the M component. This has led to reordering of the TNM combinations included in stage groups, primarily involving stage groups IIA, IIB, IIIA, and IIIB. This article summarizes the analyses and revisions for the TNM classification of lung cancer to familiarize the broader medical community and facilitate implementation of the ninth edition system.

Effectiveness and safety of segmentectomy vs. wedge resection for the treatment of patients with operable non‑small cell lung cancer: A meta‑analysis and systematic review

The present study compared the differences in effectiveness and safety between segmentectomy (ST) and wedge resection (WR) in patients with operable non-small cell lung cancer (NSCLC). The PubMed, EMBASE, Cochrane Library and Web of Science databases were searched for papers published from inception until July 2023. The inclusion criteria were based on the population, intervention, comparator, outcomes and study designs. ROBINS-I was selected to assess the risk of bias and quality of evidence in the included non-randomised studies. Appropriate effect sizes were selected, and subgroup analyses, heterogeneity tests, sensitivity analyses and publication bias were applied. A total of 18 retrospective studies were included, involving 19,381 patients with operable NSCLC. The 5-year overall survival rate [hazard ratio (HR), 0.19; 95% confidence interval (CI), 0.04, 0.34; P=0.014; I2=76.3%], lung cancer-specific survival rate (HR, 0.3; 95% CI, 0.21, 0.38; P<0.01; I2=13.8%) and metastasis rate [odds ratio (OR), 1.56; 95% CI, 1.03, 2.38; P=0.037] in patients with operable NSCLC treated with WR were worse than those in patients treated with ST. The incidence of postoperative complications (OR, 0.44; 95% CI, 0.23, 0.82) in the WR group was lower than in the ST treatment group. There was no difference in postoperative recurrence (OR, 2.15; 95% CI, 0.97, 4.74; P=0.058) and mortality (risk difference, 0.04; 95% CI, -0.03, 0.11; P=0.287) between groups. Based on current evidence, patients with NSCLC treated with ST surgery have better postoperative survival but more complications than those patients treated with WT, while the effect of WR and ST on the recurrence rate and distant metastasis rate remains controversial.

So Now We Know-Reflections on the Extent of Resection for Stage I Lung Cancer

Lobectomy has been the standard treatment for stage I lung cancer in healthy patients, largely based on a randomized trial published in 1995. Nevertheless, research has continued regarding the role of sublobar resection. Three additional randomized trials addressing resection extent in healthy patients have recently been published. These 4 trials involve differences in design, eligibility, interventions, and intraoperative processes. Patients were ineligible if intraoperative assessment demonstrated stage > IA or inadequate resection margins. All trials consistently show no differences in perioperative morbidity, mortality, and postoperative changes in lung function between sublobar resection and lobectomy-consistent with other nonrandomized evidence. Long-term outcomes are generally encouraging of lesser resection, but some inconsistencies are apparent. The 2 larger recent trials demonstrated no overall survival difference while the others suggested better survival after lobectomy versus sublobar resection. Recurrence-free survival was found to be the same after lobectomy versus sublobar resection in 3 trials, despite higher locoregional recurrences after sublobar resection. The low 5-year recurrence-free survival (64%, regardless of resection extent) in 1 recent trial highlights the need for further optimization. Thus, there is high-level evidence that sublobar resection is a reasonable alternative to lobectomy in healthy patients. However, variability in long-term results suggests that aspects of patients, tumors and interventions need to be better understood. Therefore, we propose to apply sublobar resection cautiously; especially because there are no short-term benefits. Sublobar resection requires careful attention to intraoperative details (nodes, margins), and may be best suited for less aggressive (eg, ground glass, slow growing) tumors.

Minimally invasive segmentectomy and lobectomy for peripheral stage IA1-2 non-small-cell lung cancer: a case-matched cohort study from a UK Centre

OBJECTIVES

The objective of this study is to compare in a real-world series the short- and long-term results of segmentectomy and lobectomy for peripheral clinical stage IA non-small-cell lung cancer (NSCLC).

METHODS

Single-centre cohort study including a series of consecutive patients undergoing minimally invasive segmentectomy or lobectomy for peripheral (outer third of the lung) clinical stage IA NSCLC (January 2017-August 2022). Propensity score case matching analysis generated 2 matched groups of patients undergoing segmentectomy or lobectomy. Short-term (morbidity and mortality) and long-term [overall survival and event-free survival (EFS)] outcomes were compared between the 2 matched groups. EFS was calculated by including death resulting from any cause and any recurrence as events.

RESULTS

Propensity score generated 118 pairs of patients undergoing minimally invasive segmentectomy or lobectomy. The median follow-up was 30 months (95% confidence limits (CL) 4-64). The median postoperative length of stay was 4 days in both groups. Ninety-day mortality was similar (segmentectomy 2.5% versus lobectomy 1.7%, P = 1). Three-year overall survival [segmentectomy 87% (76-93) versus lobectomy 81% (72-88), P = 0.73] and EFS [segmentectomy 82% (72-90) versus lobectomy 78% (68-84), P = 0.52] did not differ between the groups. Loco-regional recurrence rate [segmentectomy 4.2% (5/118) versus lobectomy 9.3% (11/118), P = 0.19] was similar despite a lower nodal upstaging [segmentectomy 3.4% (4/118) versus lobectomy 14% (17/118), P = 0.005]. The occurrence of compromised resection margins (pR1 or pR uncertain) was similar between the groups [segmentectomy 7.6% (9/118) versus lobectomy 9.3% (11/118), P = 0.81].

CONCLUSIONS

This observational series confirms the non-inferiority of segmentectomy compared to lobectomy in treating peripherally located stage IA NSCLC.

Sublobar resection versus lobectomy for stage IA non-small-cell lung cancer ≤ 2 cm: a systematic review and patient-level meta-analysis

Despite lobectomy being the standard of care for early-stage non-small-cell lung cancer (NSCLC), sublobar resection (segmentectomy or wedge resection) has recently been suggested to achieve similar outcomes. An electronic literature search was conducted to retrieve randomized controlled trials (RCTs) or propensity score-matched studies (PSMs) comparing lobectomy to sublobar resection in stage IA NSCLC ≤ 2 cm in size, with provision of Kaplan-Meier curves for overall survival (OS) and disease-free survival (DFS). A graphical reconstructive algorithm was used to obtain OS and DFS of individual patients, which was then pooled under random-effects individual patient data meta-analysis using Cox models to determine hazard ratios (HRs). Sensitivity analyses for OS and DFS were also performed, restricting to results from RCTs only. Seven studies (2528 patients) were retrieved. There were no significant differences in OS (shared-frailty HR = 0.92, 95% CI = 0.77-1.11, p = 0.378) or DFS (shared-frailty HR = 1.06, 95% CI = 0.90-1.24, p = 0.476) between lobectomy and sublobar resection. This comparison remained non-significant even when restricted to RCTs only. Pooled Kaplan-Meier curves of OS appeared to diverge over time, in favor of sublobar resection. This was confirmed on analysis of restricted mean survival time curves. This patient-level meta-analysis of high-quality studies demonstrates that sublobar resection is equivalent to lobectomy in patients with small stage IA NSCLC. Sublobar resection offers greater down-the-road benefits in patients who experience recurrence or a second primary tumor since the lung-sparing index surgery allows patients to receive further treatment safely. This heralds sublobar resection as the new standard of care in carefully selected early-stage patients.Trial registration: PROSPERO CRD42023385358.

CyberKnife® stereotactic radiation therapy for stage I lung cancer and pulmonary oligometastases: is fiducial implantation still relevant?-a cohort study

Background

Few studies have investigated whether there is a difference in local control or overall survival rates following treatment with robotic stereotactic body radiation therapy (SBRT) with or without prior fiducial marker implantation. Our study aimed to investigate this in patients with primary or secondary lung tumors.

Methods

A retrospective study was conducted at the Institut de Cancérologie de Lorraine of patients treated for primary lung cancer or pulmonary oligometastases with SBRT from January 2013 to July 2016. We included patients at least 18 years old who had stage I non-small cell lung cancer (NSCLC) or lung metastases and a follow-up of at least 1 month.

Results

A total of 294 patients were included. Tumors included 122 lung metastases, 89 stage I NSCLC, and 83 non-histologically confirmed lung lesions. The tracking methods were Synchrony® in 191 cases (119 gold seeds and 72 coils) and Xsight® Spine with 4D computed tomography in 103 cases. Median follow-up was 31.6 months [interquartile range (IQR), 18.1-50.2 months]. The two- and five-year probability of local control were respectively 92.22% [95% confidence interval (CI): 0.89-0.95] and 85.35% (95% CI: 0.79-0.99). The two- and five-year probability of overall survival were respectively 87.46% and 72.77% (P=0.586). Local control rates did not significantly differ between techniques at 2 and 5 years (P=0.685) (gold seeds, coils or Xsight® Spine) within tumors grouped by location, gross tumor volume (GTV) (respectively P=0.9, P=0.7, and P=0.4), planning target volume (PTV) (respectively P=0.4, P=0.9, and P=0.7), or PTV/GTV ratio (respectively P=0.6, P=0.6, and P=0.5). Metastasis-free survival and Overall survival rates did not significantly differ between techniques at 2 and 5 years (P=0.664 and P=0.586, respectively). There were no grade 4 or 5 toxicities and only one grade 3 pneumonitis and one grade 3 pneumothorax.

Conclusions

Fiducial-less SBRT using Xsight® Spine is a safe alternative to Synchrony® using gold seeds or coils, with comparable local control and overall survival rates and a similar toxicity profile.

Lung cancer with air lucency: a systematic review and clinical management guide

Background

Lung cancers with air lucency are poorly understood, often recognized only after substantial progression.

Methods

From a systematic review (PubMed and EMBASE, 2000-2022, terms related to cystic, cavitary, bulla, pseudocavitary, bubble-like, date 10-30-2022) 49 studies were selected using broad inclusion criteria (case series of ≥10 cases up to trials and reviews). There was no source of funding. Primary evidence relevant to clinical management issues was assembled. Because data was available only from heterogeneous retrospective case series, meta-analysis and formal risk-of-bias assessment was omitted. A framework was developed to guide clinical management based on the available data.

Results

Demographic, smoking and histologic differences suggest that cystic, cavitary and bullous lung cancers with air lucency may be distinct entities; insufficient data leaves it unclear whether this also applies to pseudocavitary (solid) or bubble-like (ground glass) cancers. Annual observation of irregular thin-walled cysts is warranted; a surgical diagnosis (and resection) is justified once a solid component appears because subsequent progression is often rapid with markedly worse outcomes. Bubble-like ground glass lesions should be managed similarly. Cavitary lesions must be distinguished from infection or vasculitis, but generally require needle or surgical biopsy. Pseudocavitary lesions are less well studied; positron emission tomography may be useful in this setting to differentiate scar from malignancy. Further research is needed because these conclusions are based on interpretation of retrospective case series.

Conclusions

The aggregate of available evidence suggests a framework for management of suspected lung cancers with air lucency. Greater awareness, earlier detection, and aggressive management once a solid component appears are needed. This review and framework should facilitate further research; questions include whether the suggested entities and proposed management are borne out and should involve clearly defined terms and outcomes related to progression and treatment. In summary, a conceptual understanding is emerging from interpretation of available data about a previously poorly understood topic; this should improve patient outcomes.