Upfront surgery in patients with clinical skip N2 lung cancer based on results of modern radiological examinations

Upfront surgery for stage IIIA/B non-small cell lung cancer: retrospective cohort study

BACKGROUND

Stage III non-small cell lung cancer is a heterogeneous disease. Several international guidelines recommend neoadjuvant treatment before surgery; however, upfront surgery is the preferred approach for technically resectable non-small cell lung cancer in East Asia. The aim of this retrospective study was to evaluate the long-term outcomes of curative-intent upfront surgery in stage IIIA/B non-small cell lung cancer.

METHODS

Patients who underwent curative-intent upfront surgery with stage cIIIA/B non-small cell lung cancer were identified. The clinical and pathological variables and survival outcomes were evaluated.

RESULTS

Overall, 664 patients were identified, of whom 320 (48.8%) had N2 disease, 66.7% were males, 49.4% had a smoking history, and 61.2% had lung adenocarcinoma. Lobectomy was the most performed surgical procedure (84.9%). A total of 40 patients (6.02%) had positive margins (R1/R2). The grade III adverse event rate was 2.0% (13 of 664). The median follow-up was 30.6 (range 1.9-97.7) months. At follow-up, the mortality rate was 13.3% (88 of 664) and 37.2% of patients (247 of 664) had recurrence. Lung (101 of 247 (40.9%)) and brain (53 of 247 (21.5%)) were the most common sites of recurrence. The median overall survival was 60.0 (95% c.i. 51.5 to 67.6) months, with overall survival probability at 1, 2, 3, and 5 years being 89.6%, 77.8%, 67.2%, and 49.0% respectively. The R0 cohort showed an improved median overall survival compared with the R1/R2 cohort (67.4 versus 26.5 months respectively; P = greater than 0.001). The multivariable analysis revealed that age greater than or equal to 65 years (HR 1.51, 95% c.i. 1.08 to 2.12; reference = age less than 65 years), tumour size (greater than or equal to 5 cm (HR 2.13, 95% c.i. 1.41 to 3.21) and greater than or equal to 3 cm but less than 5 cm (HR 1.15, 95% c.i. 0.78 to 1.71); reference = less than 3 cm), and adjuvant treatment (chemotherapy (HR 0.69, 95% c.i. 0.49 to 0.96) and targeted therapy (HR 0.30, 95% c.i. 0.12 to 0.76); reference = none) significantly predicted overall survival.

CONCLUSION

Upfront surgery is an option for the management of stage IIIA/B non-small cell lung cancer.

Extracapsular extension of pN2 lymph node metastases is not prognostically significant in surgically resected patients with non-small cell lung cancer

Objectives

In patients with non-small cell lung cancer (NSCLC) the pathologic lymph node status N2 is a heterogeneous entity, with different degrees of lymph node involvement representing different prognoses. It is speculated whether extra capsular nodal extension may help to define a subgroup with implications on long-term survival.

Methods

We retrospectively identified 118 patients with non-small cell lung cancer (65 men, 53 women), who were treated between 2013 and 2018 and found to have pathologic N2 lymph node involvement. In all patients lung resection with systematic mediastinal and hilar lymph node dissection was performed with curative intent. In N2 lymph node metastases capsules of affected lymph nodes were examined microscopically as to whether extracapsular extension was present.

Results

51 patients (43 %) had extracapsular extension (ENE). Most of these patients (n=35) only had ENE in a single lymph node (69 %). The overall 5-year survival rate was 24.6 % and progression-free survival rate 17.8 %. In the multivariate analysis OS was worse for patients with multiple affected pN2 stations, concurrent N1 metastases, increasing age, and larger tumor size. For the percentage of lymph nodes affected with ENE (of total examined) only a non-significant trend towards worse OS could be observed (p=0.06).

Conclusions

Although we could not demonstrate significant prognostic differences between N2 extra capsular nodal involvement within our patient population, other analyses may yield different results. However, clinicians should continue performing thorough lymph nodes dissections in order to achieve local complete resection even in patients with extra capsular tumor spread.

Survival outcome of upfront surgery for clinical single-station N2 non-small cell lung cancer

BACKGROUND

Pathological N2 (pN2) non-small cell lung cancer (NSCLC) is diverse; its treatment depends on the clinical N (cN) status. We aimed to determine the efficacy of upfront surgery for cN2pN2 NSCLC.

METHODS

The study included 43 cN2pN2 NSCLC patients who underwent upfront surgery at the Shizuoka Cancer Center between 2002 and 2017. Survival outcome, focusing on cN2 status, was retrospectively investigated. Mediastinal lymph nodes were pre-operatively evaluated using computed tomography and positron emission tomography. Surgical eligibility criteria included single-station cN2. N2 with N1 and skip N2 were defined as N2 with and without ipsilateral hilar lymph node metastasis, respectively. A platinum-doublet regimen was used for adjuvant chemotherapy. Survival curves were analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazard regression model.

RESULTS

Clinical-skip N2 and cN2 with N1 cases included 22 and 21 patients, respectively. Twenty-three patients received adjuvant chemotherapy. The median follow-up duration was 73 months. Clinical-skip N2 had a significantly better 5-year recurrence-free survival (RFS) than cN2 with N1 (58.3 vs 28.6%, P = 0.038) and was an independent favorable RFS predictor. Recurrence within 18 months occurred in 71% of cN2 with N1 cases. Five-year overall survival and RFS rates in patients receiving adjuvant chemotherapy vs those without adjuvant chemotherapy were 82.2 vs 41.9% (P = 0.019) and 56.5 vs 28.0% (P = 0.049), respectively.

CONCLUSIONS

Clinical-skip N2 had an excellent prognosis, and upfront surgery was acceptable. Conversely, upfront surgery followed by chemotherapy is not recommended for cN2 with N1 patients because of early recurrence.

Real-world treatment patterns in resectable (stages I-III) non-small-cell lung cancer: a systematic literature review

Aim: The aim of this systematic literature review was to describe treatment patterns in non-metastatic non-small-cell lung cancer. Methods: A search was conducted in MEDLINE and EMBASE. Eligible studies were multicentered (>50 patients) and conducted after 2000 in North America, Europe and Asia. Results: Twenty studies met the eligibility criteria. Based on US and Canadian studies in the resectable population, the proportion of patients who received neoadjuvant chemotherapy/chemoradiotherapy and adjuvant chemotherapy/chemoradiotherapy increased with increasing stage (i.e., from <3% in stage I to about 40% in stage III and from 15% in stage I to 30% in stage III, respectively). Within the resectable population, the breakdown between bimodal and trimodal therapy was variable, suggesting that clinical practice is not uniform. Conclusion: Overall, studies were heterogeneous, precluding data extrapolation across regions. Despite heterogeneity and limited evidence, this review suggested an increase in neoadjuvant and adjuvant chemotherapy with increasing stage, generally in line with treatment guidelines.

The importance of anatomical localization of non-small cell lung carcinoma in predicting mediastinal lymph node metastasis

Bronchopulmonary segmental location of non-small lung carcinomas is closely related to metastatic lymph node foci in the mediastinum. Our aim was to investigate the relationship between the anatomical locations of pulmonary masses on the bronchopulmonary segmental base and metastatic lymph node regions in non-small cell lung cancer using preoperative 18F-FDG PET/CT images. Ninety patients newly diagnosed with non-small cell lung carcinoma and referred to PET/CT imaging for staging were included in the study. Tumoral masses that could be evaluated visually and mediastinal node metastases were identified in 18F-FDG PET/CT images, then the relationship between them was investigated statistically. The diagnostic power of 18F-FDG PET/CT of mediastinal nodes was also revealed. Seventy-four males (82.2%) and sixteen females (17.8%) were enrolled in the study. Half of the patients were diagnosed as adenocarcinoma (50%). Investigation of the tumor location and mediastinal metastatic nodes revealed a statistically significant relationship between the apicoposterior segment of the left superior lobe and the left upper and lower paratracheal, subaortic, paraaortic, and left hilar regions according to the IASLC map. The sensitivity, specificity and accuracy of 18F-FDG PET/CT in the mediastinal nodes were 69.2%, 66.6%, and 68%, respectively. There was no statistically significant relationship between tumor location and 8th TNM Stage. Anatomical locations of non-small cell lung carcinomas can affect the disease stage and prognosis because of their tendency to metastasize to some mediastinal regions. However, this relationship needs to be investigated in larger study groups.

Prediction of Unexpected N2 Disease Associated With Clinical T1-2N0-1M0 Non-Small-Cell Lung Cancer

BACKGROUND

Despite the recent development of radiologic mediastinal staging modality, unexpected mediastinal lymph node metastasis still occurs. Preoperative accurate nodal staging is important to determine the optimal treatment. Therefore, this study aimed to identify predictors of unexpected N2 disease in non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Data from a multicenter database of 2802 patients with clinical T1-2N0-1M0 NSCLC who underwent anatomical segmentectomy or lobectomy were retrospectively analyzed. Unexpected N2 disease was defined as pathologic N2 disease with clinical N0 or N1. The predictive criteria of unexpected N2 disease were established on the basis of the multivariable analysis results of a derivation cohort of 2019 patients, and the criteria were further tested in a validation cohort of 783 patients.

RESULTS

In multivariable analyses, maximum standardized uptake value (SUV_max) of the primary tumor on 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (odds ratio, 1.072; 95% confidence interval, 1.018-1.129; P = .008) and clinical N1 (vs. clinical N0) disease (odds ratio, 5.40; 95% confidence interval, 1.829-15.94; P = .002) were independent predictors of unexpected N2 disease. The predictive criteria of unexpected N2 disease was defined as tumors with SUV_max of ≥ 3.1, determined by receiver operating characteristic curves, and clinical N1 disease. This criterion showed diagnostic accuracy of 90.6% (sensitivity 32.0%, specificity 94.5%) in the derivation cohort and 91.3% (sensitivity 32.6%, specificity 94.7%) in the validation cohort.

CONCLUSION

The predictive criteria of unexpected N2 disease (tumors with SUV_max of ≥ 3.1 and clinical N1) can be used to select candidates for preoperative invasive mediastinal staging in patients with clinical T1-2N0-1M0 NSCLC.

Prognostic factors for overall survival of stage III non-small cell lung cancer patients on computed tomography: A systematic review and meta-analysis

INTRODUCTION

Prognosis prediction is central in treatment decision making and quality of life for non-small cell lung cancer (NSCLC) patients. However, conventional computed tomography (CT) related prognostic factors may not apply to the challenging stage III NSCLC group. The aim of this systematic review was therefore to identify and evaluate CT-related prognostic factors for overall survival (OS) of stage III NSCLC.

METHODS

The Medline, Embase, and Cochrane electronic databases were searched. After study selection, risk of bias was estimated for the included studies. Meta-analysis of univariate results was performed when sufficient data were available.

RESULTS

1595 of the 11,996 retrieved records were selected for full text review, leading to inclusion of 65 studies that reported data of 144,513 stage III NSCLC patients andcompromising 26 unique CT-related prognostic factors. Relevance and validity varied substantially, few studies had low relevance and validity. Only four studies evaluated the added value of new prognostic factors compared with recognized clinical factors. Included studies suggested gross tumor volume (meta-analysis: HR = 1.22, 95%CI: 1.05-1.42), tumor diameter, nodal volume, and pleural effusion, are prognostic in patients treated with chemoradiation. Clinical T-stage and location (right/left) were likely not prognostic within stage III NSCLC. Inconclusive are several radiomic features, tumor volume, atelectasis, location (pulmonary lobes, central/peripheral), interstitial lung abnormalities, great vessel invasion, pit-fall sign, and cavitation.

CONCLUSIONS

Tumor-size and nodal size-related factors are prognostic for OS in stage III NSCLC. Future studies should carefully report study characteristics and contrast factors with guideline recognized factors to improve evidence evaluation and validation.

New perspective to evaluate N1 staging: The peripheral lymph node metastasis status of non-small cell lung cancer

Background

Lymph node (LN) metastasis status is the decision‐making basis for the surgical procedure and adjuvant therapy modalities. Fewer studies have previously focused on LN metastasis in N1 station, especially on peripheral lymph node (PLN) metastasis in N1 station. This study aimed to reveal the metastasis status of PLN of non‐small cell lung cancer (NSCLC), and investigate its effects on N staging.

Methods

We retrospectively evaluated a consecutive series of patients who underwent curative resection for histologically confirmed N1 NSCLC. Propensity score matching (PSM) was used to analyze the effects of PLN on N staging.

Results

A total of 105 patients with confirmed pathological N1 (pN1) stage NSCLC with solitary nodule and without neoadjuvant therapy were enrolled into the study: 55 patients had intraperipheral LN metastasis (IPLNM), and 50 patients had extra‐peripheral LN metastasis (EPLNM). Before PSM analysis, type of location (P = 0.002), surgical procedure (P = 0.008), number of positive LNs (P = 0.029), number of LNs removed (P = 0.010), lobe of lung cancer (P = 0.031), and vascular invasion (P = 0.049) showed significant differences between the two groups. After PSM analysis, statistically there were differences in type of location (P = 0.034), number of positive LNs (P = 0.008) and vascular invasion (P = 0.049) between them.

Conclusion

PLN metastasis was a quite common pattern of LN metastasis in N1 station of NSCLC. IPLNM occurred more frequently in central NSCLC and NSCLC with vascular invasion, and thoracotomy was likely to secure more accurate PLN staging. Clinicians should pay great attention to PLN dissection. Follow‐up data will be needed in order to detect the prognosis of IPLNM patients.