Predictors of Outcomes after Surgical Treatment of Synchronous Primary Lung Cancers

Differentiating Separate Primary Lung Adenocarcinomas From Intrapulmonary Metastases With Emphasis on Pathological and Molecular Considerations: Recommendations From the International Association for the Study of Lung Cancer Pathology Committee

INTRODUCTION

With the implementation of low-dose computed tomography screening, multiple pulmonary tumor nodules are diagnosed with increasing frequency and the selection of surgical treatments versus systemic therapies has become challenging on a daily basis in clinical practice. In the presence of multiple carcinomas, especially adenocarcinomas, pathologically determined to be of pulmonary origin, the distinction between separate primary lung carcinomas (SPLCs) and intrapulmonary metastases (IPMs) is important for staging, management, and prognostication.

METHODS

We systemically reviewed various means that aid in the differentiation between SPLCs and IPMs explored by histopathologic evaluation and molecular profiling, the latter includes DNA microsatellite analysis, array comparative genomic hybridization, TP53 and oncogenic driver mutation testing and, more recently, with promising effectiveness, next-generation sequencing comprising small- or large-scale multi-gene panels.

RESULTS

Comprehensive histologic evaluation may suffice to differentiate between SPLCs and IPMs. Nevertheless, molecular profiling using larger-scale next-generation sequencing typically provides superior discriminatory power, allowing for more accurate classification. On the basis of the literature review and expert opinions, we proposed a combined four-step histologic and molecular classification algorithm for addressing multiple pulmonary tumor nodules of adenocarcinoma histology that encourages a multidisciplinary approach. It is also noteworthy that new technologies combining machine learning and digital pathology may develop into valuable diagnostic tools for distinguishing SPLCs from IPMs in the future.

CONCLUSIONS

Although histopathologic evaluation is often adequate to differentiate SPLCs from IPMs, molecular profiling should be performed when possible, especially in cases with tumors exhibiting similar morphology. This manuscript summarized the previous efforts in resolving the current challenges and highlighted the recent progress in the differentiation methods and algorithms used in categorizing multiple lung adenocarcinomas into SPLCs or IPMs, which are becoming more and more critical in precision lung cancer management.

Super multiple primary lung cancers harbor high-frequency BRAF and low-frequency EGFR mutations in the MAPK pathway

The incidence of multiple primary lung cancer (MPLC) is increasing, with some of our surgical patients exhibiting numerous lesions. We defined lung cancer with five or more primary lesions as super MPLCs. Elucidating the genomic characteristics of this special MPLC subtype can help reduce disease burden and understand tumor evolution. In our cohort of synchronous super early-stage MPLCs (PUMCH-ssesMPLC), whole-exome sequencing on 130 resected malignant specimens from 18 patients provided comprehensive super-MPLC genomic landscapes. Mutations are enriched in PI3k-Akt and MAPK pathways. Their BRAF mutation frequency (31.5%) is significantly higher than MPLC with fewer lesions and early-stage single-lesion cancer, while EGFR mutations are significantly fewer (13.8%). As lesion counts increase, BRAF mutations gradually become dominant. Also, invasive lesions more tend to have classic super-MPLC mutation patterns. High-frequency BRAF mutations, especially Class II, and low-frequency EGFR mutations could be a reason for the limited effectiveness of targeted therapy in super-MPLC patients.

Classification of multiple primary lung cancer in patients with multifocal lung cancer: assessment of a machine learning approach using multidimensional genomic data

Background

Multiple primary lung cancer (MPLC) is an increasingly well-known clinical phenomenon. However, its molecular characterizations are poorly understood, and still lacks of effective method to distinguish it from intrapulmonary metastasis (IM). Herein, we propose an identification model based on molecular multidimensional analysis in order to accurately optimize treatment.

Methods

A total of 112 Chinese lung cancers harboring at least two tumors (n = 270) were enrolled. We retrospectively selected 74 patients with 121 tumor pairs and randomly divided the tumor pairs into a training cohort and a test cohort in a 7:3 ratio. A novel model was established in training cohort, optimized for MPLC identification using comprehensive genomic profiling analyzed by a broad panel with 808 cancer-related genes, and evaluated in the test cohort and a prospective validation cohort of 38 patients with 112 tumors.

Results

We found differences in molecular characterizations between the two diseases and rigorously selected the characterizations to build an identification model. We evaluated the performance of the classifier using the test cohort data and observed an 89.5% percent agreement (PA) for MPLC and a 100.0% percent agreement for IM. The model showed an excellent area under the curve (AUC) of 0.947 and a 91.3% overall accuracy. Similarly, the assay achieved a considerable performance in the independent validation set with an AUC of 0.938 and an MPLC predictive value of 100%. More importantly, the MPLC predictive value of the classification achieved 100% in both the test set and validation cohort. Compared to our previous mutation-based method, the classifier showed better κ consistencies with clinical classification among all 112 patients (0.84 vs. 0.65, p <.01).

Conclusion

These data provide novel evidence of MPLC-specific genomic characteristics and demonstrate that our one-step molecular classifier can accurately classify multifocal lung tumors as MPLC or IM, which suggested that broad panel NGS may be a useful tool for assisting with differential diagnoses.

The characteristics and prognosis of different disease patterns of multiple primary lung cancers categorized according to the 8th edition lung cancer staging system

INTRODUCTION

The 8th edition lung cancer staging system was the first to describe the detailed diagnosis and staging of multiple primary lung cancers (MPLC). However, the characteristics and prognosis of MPLC categorized according to the new system have not been evaluated.

METHOD

We retrospectively analyzed data from surgically treated MPLC patients in a single center from 2011 to 2013 and explored the characteristics and outcomes of different MPLC disease patterns.

RESULTS

In total, 202 surgically treated MPLC patients were identified and classified into different groups according to disease categories and diagnostic time (multifocal ground glass/lepidic (GG/L) nodules: n = 139, second primary lung cancer (SPLC): n = 63, simultaneous MPLC (sMPLC): n = 171, and metachronous MPLC (mMPLC): n = 31). There were significant differences in clinical characteristics between SPLC and GG/L nodule patients and simultaneous and metachronous MPLC patients. The overall 1-, 3-, and 5-year lung cancer-specific survival rates of MPLC were 97.98%, 90.18%, and 82.81%, respectively. Five-year survival was better in patients with multiple GG/L nodules than in those with SPLC (87.94% vs. 71.29%, P < 0.05). Sex was an independent prognostic factor for sMPLC (5-year survival, female vs. male, 88.0% vs. 69.5%, P < 0.05), and in multiple tumors, the highest tumor stage was an independent prognostic factor for all categories of MPLC.

CONCLUSIONS

The different disease patterns of MPLC have significantly different characteristics and prognoses. Clinicians should place treatment emphasis on the tumor with the highest stage as it is the main contributor to the prognosis of all categories of MPLC patients.

Uniportal Video-Assisted Thoracoscopic Surgery Completion Lobectomy Long after Wedge Resection or Segmentectomy in the Same Lobe: A Bicenter Study

BACKGROUND

Completion lobectomy (CL) following a prior resection in the same lobe may be complicated by severe pleural or hilar adhesions. The role of uniportal video-assisted thoracoscopic surgery (U-VATS) has never been evaluated in this setting.

METHODS

Data were collected from two Italian centers. Between 2015 and 2022, 122 patients (60 men and 62 women, median age 67.7 ± 8.913) underwent U-VATS CL at least 4 weeks after previous lung surgery.

RESULTS

Twenty-eight (22.9%) patients were affected by chronic obstructive pulmonary disease (COPD) and twenty-five (20.4%) were active smokers. Among the cohort, the initial surgery was performed using U-VATS in 103 (84.4%) patients, triportal-VATS in 8 (6.6%), and thoracotomy in 11 (9.0%). Anatomical segmentectomy was the initial surgery in 46 (37.7%) patients, while hilar lymphadenectomy was performed in 16 (13.1%) cases. CL was performed on 110 (90.2%) patients, segmentectomy on 10 (8.2%), and completion pneumonectomy on 2 (1.6%). Upon reoperation, moderate pleural adhesions were observed in 38 (31.1%) patients, with 2 (1.6%) exhibiting strong adhesions. Moderate hilar adhesions were found in 18 (14.8%) patients and strong adhesions in 11 (9.0%). The median operative time was 203.93 ± 74.4 min. In four (3.3%) patients, PA taping was performed. One patient experienced intraoperative bleeding that did not require conversion to thoracotomy. Conversion to thoracotomy was necessary in three (2.5%) patients. The median postoperative drainage stay and postoperative hospital stay were 5.67 ± 4.44 and 5.52 ± 2.66 days, respectively. Postoperative complications occurred in 34 (27.9%) patients. Thirty-day mortality was null. Histology was the only factor found to negatively influence intraoperative outcomes (p = 0.000). Factors identified as negatively impacting postoperative outcomes at univariate analyses were male sex (p = 0.003), age > 60 years (p = 0.003), COPD (p = 0.014), previous thoracotomy (p = 0.000), previous S2 segmentectomy (p = 0.001), previous S8 segmentectomy (p = 0.008), and interval between operations > 5 weeks (p= 0.005). In multivariate analysis, only COPD confirmed its role as an independent risk factor for postoperative complications (HR: 5.12, 95% CI (1.07-24.50), p = 0.04).

CONCLUSIONS

U-VATS CL seems feasible and safe after wedge resection and anatomical segmentectomy.

Predictors of residual simultaneous multiple ground-glass nodule progression after dominant lesion resection

OBJECTIVE

This study aimed to identify the predictive factors for the progression of residual simultaneous multifocal ground-glass nodules (SMGGNs) after resection of the dominant lesion.

METHODS

Patients (n = 3420) with primary lung cancer who underwent lung resections at our hospital between 2006 and 2016 were screened, and the data from 82 patients who had residual SMGGNs after undergoing surgery for the dominant lesion (pathologically stage 0-IIA) were retrospectively analyzed. Clinicopathological factors that predicted the growth of residual second dominant GGNs were identified.

RESULTS

Median total tumor and solid component sizes of the residual second dominant GGNs were 1.3 cm (interquartile range [IQR]: 0.6-2.0) and 0 cm (IQR: 0-0.7), respectively. During a median follow-up period of 54 months (IQR: 37-78 months), 35 (43%) lesions progressed. Logistic regression analysis revealed that age younger than 70 (OR: 10.54, 95% CI: 1.71-65.11), a dominant lesion with pure solid appearance (reference: GGN, OR: 18.16, 95% CI: 1.66-198.60), a second dominant GGN total size larger than 1.0 cm (OR: 12.27, 95% CI: 1.85-81.17), and a second dominant GGN solid component size larger than 0.5 cm (OR: 17.59, 95% CI: 3.58-86.47) were significant predictive factors for the progression of residual GGNs (all p values < 0.03). Based on an analysis of growth patterns, rapid growth was higher in second dominant GGNs with a part-solid appearance.

CONCLUSIONS

If the resected dominant lesion or the residual second dominant GGN exhibits high-risk factors, the second dominant GGN should be meticulously observed.

Contemporary Incidence of Synchronous Multiple Primary Lung Cancers and Survival in the Era of Lung Cancer Screening

OBJECTIVE

Up to 15% of lung cancer patients have multiple suspicious nodules. While some of these nodules may represent metastatic lung cancer, others represent synchronous multiple primary lung cancer (SMPLC). The incidence of SMPLC ranges from 0.8% to 8.4% and appears to be increasing. Inconsistent identification of SMPLC can be detrimental for patients who are misdiagnosed as having intrapulmonary metastasis and not offered stage-based treatment. We sought to identify the contemporary incidence of SMPLC at a tertiary institution.

METHODS

From January 2018 to September 2019, patients who underwent lung cancer resection were retrospectively reviewed. Patients with SMPLC were identified using the modified Martini-Melamed criteria.

RESULTS

During the 21-month period, 227 patients underwent lung cancer resection. There were 47 patients (20.7%) who had 119 pathologically confirmed SMPLC. Most patients had ipsilateral tumors (n = 24, 51.1%) with at least 1 adenocarcinoma (n = 40, 85.1%). Considering histologic subtyping, 38 (80.9%) had histologically distinct tumors. Overall and cancer-specific survival at 4 years was 86% and 90%, respectively. Only patients with 3 or more SMPLC had poor 4-year overall (P = 0.002) and cancer-specific survival (P = 0.043) compared with those with 2 SMPLC. Patient demographics, histology, tumor location, and highest pathologic staging did not affect survival outcomes.

CONCLUSIONS

Using a strict inclusion criterion, the incidence of SMPLC is higher than previously reported. SMPLC patients have favorable survival outcomes, suggesting that they behave like primary lung cancer, not intrapulmonary metastasis. Awareness of SMPLC by thoracic surgeons is critical in optimizing outcomes in this patient population.

A pairwise radiomics algorithm-lesion pair relation estimation model for distinguishing multiple primary lung cancer from intrapulmonary metastasis

Background

Distinguishing multiple primary lung cancer (MPLC) from intrapulmonary metastasis (IPM) is critical for their disparate treatment strategy and prognosis. This study aimed to establish a non-invasive model to make the differentiation pre-operatively.

Methods

We retrospectively studied 168 patients with multiple lung cancers (307 pairs of lesions) including 118 cases for modeling and internal validation, and 50 cases for independent external validation. Radiomic features on computed tomography (CT) were extracted to calculate the absolute deviation of paired lesions. Features were then selected by correlation coefficients and random forest classifier 5-fold cross-validation, based on which the lesion pair relation estimation (PRE) model was developed. A major voting strategy was used to decide diagnosis for cases with multiple pairs of lesions. Cases from another institute were included as the external validation set for the PRE model to compete with two experienced clinicians.

Results

Seven radiomic features were selected for the PRE model construction. With major voting strategy, the mean area under receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity of the training versus internal validation versus external validation cohort to distinguish MPLC were 0.983 versus 0.844 versus 0.793, 0.942 versus 0.846 versus 0.760, 0.905 versus 0.728 versus 0.727, and 0.962 versus 0.910 versus 0.769, respectively. AUCs of the two clinicians were 0.619 and 0.580.

Conclusions

The CT radiomic feature-based lesion PRE model is potentially an accurate diagnostic tool for the differentiation of MPLC and IPM, which could help with clinical decision making.

Association of the Extent of Resection with Survival in Multiple Primary Lung Cancer: A Systematic Review

BACKGROUND

The incidence of synchronous multiple primary lung cancer (SMPLC) has progressively increased, due to recent advances in imaging. To date, no guidelines defining recommendations for patients' selection and no standard treatment of cases with SMPLC have been defined.The primary aim of this systematic review was to assess survival among patients treated with lobectomy or sublobar resection MPLC.

METHODS

Comprehensive literature search of Medline, the Cochrane Library, reference lists, and ongoing studies was performed according to a prospectively registered design (PROSPERO: CRD42019115487). All studies published between 1998 and December 2020 that examined treatments with lobectomy compared to sublobar resection were included. Two double-blind investigators independently selected articles.Primary outcomes were to assess the 5-year overall survival (OS) rate among patients treated with lobectomy or sublobar resection and the impact of lymph node status on 5-year OS and 5-year disease-free survival in patients with MPLC.

RESULTS

The search yielded 424 articles; 4 observational studies met the inclusion criteria and collectively evaluated 298 patients with a mean age ranging from 61.5 to 67 years. A total of 112 patients were treated for bilateral synchronous tumors and 186 patients for unilateral multiple synchronous tumors. All included studies showed that the type of resection, lobectomy or limited resection, had no significant impact on survival.

CONCLUSION

Limited resection is a valuable treatment option for MPLC. However, the clinical level of evidence of the studies found is low and randomized studies are needed to clarify the extent of resection in MPLC.

Multiple primary lung cancer: Updates of clinical management and genomic features

In recent decades, multiple primary lung cancer (MPLC) has been increasingly prevalent in clinical practice. However, many details about MPLC have not been completely settled, such as understanding the driving force, clinical management, pathological mechanisms, and genomic architectures of this disease. From the perspective of diagnosis and treatment, distinguishing MPLC from lung cancer intrapulmonary metastasis (IPM) has been a clinical hotpot for years. Besides, compared to patients with single lung lesion, the treatment for MPLC patients is more individualized, and non-operative therapies, such as ablation and stereotactic ablative radiotherapy (SABR), are prevailing. The emergence of next-generation sequencing has fueled a wave of research about the molecular features of MPLC and advanced the NCCN guidelines. In this review, we generalized the latest updates on MPLC from definition, etiology and epidemiology, clinical management, and genomic updates. We summarized the different perspectives and aimed to offer novel insights into the management of MPLC.

Pulmonary completion lobectomy after segmentectomy: An integrated analysis of perioperative outcomes

Background

Completion lobectomy (CL) after anatomical segmentectomy is technically challenging and rarely performed. Here, we aimed to report perioperative outcomes of a single center real‐world CL data.

Methods

Seven patients who underwent CL after segmentectomy were retrospectively evaluated between 2015–2021. Additionally, 34 patients were included in the review based on relevant studies in the literature until March 2022. A total of 41 patients were finally analyzed and classified into groups, according to surgical approach (video‐assisted thoracic surgery [VATS] and thoracotomy; 12 and 29 patients, respectively) or interval‐to‐CL following initial segmentectomy (≤8 weeks [short] and >8 weeks [long]; 11 and 30 patients, respectively).

Results

There were no significant differences in estimated blood loss, postoperative hospital stay, or complications between the predefined groups. However, a longer operative time was observed in the long interval‐to‐CL group than in the short interval‐to‐CL group (267 vs. 226 min, p = 0.02). The rate of severe hilar adhesions was higher in the thoracotomy versus VATS groups (72 vs. 42%, p = 0.06) and in the long versus short interval‐to‐CL groups (70 vs. 45%, p = 0.15). On multivariable logistic regression analysis of a subgroup (n = 30), completion lobectomy of upper lobes may be associated with severe hilar adhesions (p = 0.02, odds ratio: 13.98; 95% confidence interval [CI]: 1.36–143.71).

Conclusion

Completion lobectomy after segmentectomy can be performed securely by either VATS or thoracotomy. Although the thoracotomy and long interval‐to‐CL groups retained a greater percentage of severe hilar adhesions, the perioperative outcomes were similar to those of VATS and short interval‐to‐CL groups, respectively.

Radiological classification, gene-mutation status, and surgical prognosis of synchronous multiple primary lung cancer

OBJECTIVE

To investigate the radiological classification, gene-mutation status, and surgical prognosis of synchronous multiple primary lung cancer (sMPLC).

METHODS

From January 2013 to October 2019, 192 consecutive patients with sMPLC were investigated. The clinical, CT, molecular, and pathological features of all patients were analyzed. Furthermore, the prognosis of 89 patients who only underwent surgical resection was evaluated.

RESULTS

Among 192 patients, all lesions pathologically confirmed or highly suspected as tumors based on radiological findings were retrospectively analyzed, and the CT findings of sMPLC were classified into three types: (I) all lesions manifested as solid nodules/masses (14.06%, 27/192), (II) all lesions manifested as subsolid nodules/masses (43.23%, 83/192), and (III) tumor lesions manifested as a combination of ≥ 2 of the following patterns: solid nodules/masses, subsolid nodules/masses, cystic airspace, and focal consolidation (42.71%, 82/192). For 252 tumors undergoing epidermal growth factor receptor (EGFR)-mutation testing, the EGFR-mutation rate was higher in subsolid tumors than that in solid tumors (p < 0.05). Among 19 patients with all tumors undergoing surgery and driver-gene testing, genetic heterogeneity was prevalent among the multiple tumors (63.16%,12/19). The highest clinical stage of non-I, ipsilateral distribution of tumors, and CT classification of I indicated a poor prognosis for patients with sMPLC (all p < 0.05).

CONCLUSION

Subsolid lesions are the most common presentation of sMPLC. Genetic heterogeneity in driver mutations among sMPLC may be present. Prognosis in patients with sMPLC is determined by the highest clinical TNM stage, distribution, and radiological classification among the multiple tumors.

KEY POINTS

• Synchronous multiple primary lung cancer (sMPLC) has three types of CT findings. • Genetic heterogeneity may be prevalent among the multiple tumors. • Prognosis in patients with sMPLC is associated with the highest clinical TNM stage, distribution, and radiological classification among the multiple tumors.

Surgical strategies for patients with second primary non-small cell lung cancer lesions 2 cm or less in diameter

BACKGROUND AND PURPOSE

The wide application of low-dose computed tomography (CT) has led to an increase in the detection of small lung cancer lesions. Moreover, surgical recommendations for second primary non-small cell lung cancer (NSCLC) lesions ≤ 2 cm are obscure. This study compares the efficacy of wedge resection, lobectomy, and segmentectomy for small second primary NSCLC lesions.

METHODS

The cohort was established based on the SEER database. Univariate and multivariate cox regression analysis, least absolute shrinkage and selection operator (LASSO) regression, and restricted mean survival time (RMST) values were applied to identify prognostic factors. We used the Kaplan-Meier method to plot the survival curves of the different subgroups according to propensity score matching (PSM) analysis to then compare the therapeutic efficacy of the surgical procedures.

RESULTS

A total of 568 patients were enrolled in this study. Age, sex, grade, and lymph node ratio were selected as independent prognostic factors (p < 0.05). No significant differences were observed in survival probabilities among the groups of patients who underwent segmentectomy, wedge resection, or lobectomy (p > 0.05). We also established a nomogram model based on the four prognostic factors to guide clinical treatment.

CONCLUSIONS

Based on the findings of our study, segmentectomy was more appropriate than lobectomy for patients with a second primary NSCLC lesion ≤ 2 cm in diameter. The evidence to support other recommendations is insufficient.

Oligometastatic Disease in Non-Small-Cell Lung Cancer: An Update

Simple Summary

Approximately 7–50% of patients with non-small-cell lung cancer (NSCLC) develop oligometastases, which are new tumors found in another part of the body, arising from cancer cells of the original tumor that have travelled through the body. In recent years, these patients have been increasingly regarded as a distinct group that could benefit from treatment that intends to cure the disease, rather than palliative care, to achieve a better clinical outcome. Various treatment procedures have been developed for treating NSCLC patients with different oligometastatic sites. In addition, the newly proposed uniform definition for oligometastases as well as ongoing trials may lead to increased appropriate patient selection and evaluation of treatment effectiveness. The aim of this review article is to summarize the latest evidence regarding optimal management strategies for NSCLC patients with oligometastases.

Abstract

Oligometastatic non-small-cell lung cancer (NSCLC) is a distinct entity that is different from localized and disseminated diseases. The definition of oligometastatic NSCLC varies across studies in past decades owing to the use of different imaging modalities; however, a uniform definition of oligometastatic NSCLC has been proposed, and this may facilitate trial design and evaluation of certain interventions. Patients with oligometastatic NSCLC are candidates for curative-intent management, in which local ablative treatment, such as surgery or stereotactic radiosurgery, should be instituted to improve clinical outcomes. Although current guidelines recommend that local therapy for thoracic and metastatic lesions should be considered for patients with oligometastatic NSCLC with stable disease after systemic therapy, optimal management strategies for different oligometastatic sites have not been established. Additionally, the development of personalized therapies for individual patients with oligometastatic NSCLC to improve their quality of life and overall survival should also be addressed. Here, we review relevant articles on the management of patients with oligometastatic NSCLC and categorize the disease according to the site of metastases. Ongoing trials are also summarized to determine future directions and expectations for new treatment modalities to improve patient management.

Clinical Features and Surgical Treatment of Synchronous Multiple Primary Lung Adenocarcinomas With Different EGFR Mutations

Background

With the popularity of lung cancer screening and advances in imaging technology, more and more synchronous multiple primary lung adenocarcinomas (SMPLA) are being diagnosed clinically, however, the clinical characteristics and prognosis of SMPLA with different EGFR mutations remains unclear. We aimed to explore clinical features and surgical outcomes of these patients to aid in the diagnosis and treatment of SMPLA.

Methods

Medical records of patients with different EGFR mutations who have been diagnosed as SMPLA and underwent surgical resection from March 2015 to December 2019 were retrospectively analyzed. Clinical characteristics, surgical outcomes, recurrence-free survival (RFS) and overall survival (OS) were investigated.

Results

A total of 70 patients (68.6% female and 77.1% non-somkers) were included. Total of 161 lesions in all patients, 84.4% were ground-glass opacity (GGO) lesions. EGFR mutations were detected in 108 lesions, most of which were L858R (35.4%) and 19Del (20.5%). The mutation rate of mixed GGO is significantly higher than that of pure GGO and solid nodules (SN); the mutation rate of invasive adenocarcinoma is significantly higher than that of other histology subtypes; the mutation rate of lesions >20 mm was significantly higher than that of ≤20 mm. However, there is no significant difference in the mutation rate of specific driver gene between different radiological features, pathological characteristics and sizes. After a median follow-up time of 29 months, the 3-year OS and RFS were 94.4% and 86.0%, respectively.

Conclusions

A high discordance of EGFR mutations were identified between tumors in patients with SMPLA. Synchronous multiple lung adenocarcinomas with predominantly multiple GGO should be considered as SMPLA, and surgery may be aggressively performed for these patients due to a good prognosis.

Genomic profiles and their associations with TMB, PD-L1 expression, and immune cell infiltration landscapes in synchronous multiple primary lung cancers

Background

Diagnosing and treating patients with multiple primary lung cancers (MPLCs) bring challenges to the clinic, and the preliminary evidence has revealed unsatisfying outcomes after targeted therapy and immunotherapy. Therefore, we surveyed genomic profiles of MPLCs and their possible associations with tumor mutation burden (TMB), programmed death-ligand 1 (PD-L1), and the immune cell infiltration landscape.

Materials and methods

A total of 112 patients with MPLCs with surgically resected 294 tumors were eligible, and 255 tumors were sequenced using a 1021-gene panel. Immunohistochemistry staining was performed to evaluate the levels of PD-L1 and the density of CD3+/CD8+ tumor-infiltrating lymphocytes (TILs), and CD68+/CD163+ tumor-associated macrophages (TAMs) at the central tumor and invasive margin, and immunotypes were generated based on those variables.

Results

MPLCs often occur simultaneously in non-smoker women younger than 60 years and manifest as ground-glass opacities, adenocarcinoma, and stage I lung lesions. The most frequently mutated genes in the 255 tumors were EGFR (56%), ERBB2 (12%), TP53 (12%), BRAF (11%), RBM10 (11%), and KRAS (9%). We found 87 (77.7%) patients with diverse genomic profiles, and 61 (54.5%) who shared at least one putative driver gene between different tumors presented more aggressive tumors. The median TMB was 1.92 mutations/Mb, and high-TMB (≥3) lesions often harbored EGFR^L858R/KRAS^G12C/RBM10/TP53/LRP1B mutations or wild-type ERBB2. Only 8.1% of patients and 3.9% of lesions were positive for PD-L1 on tumor cells, and this positivity was more frequent in LRP1B/TP53-mutant tumors. EGFR^L858R/RBM10/TP53 mutations were positively associated with specific immune cells and an inflamed immunotype, but ERBB2 mutations were negatively correlated. TMB, CD3+TILs, and CD68+/CD163+ TAMs presented with significant heterogeneity among paired tumors (all kappa <0.2), but PD-L1 and CD8 +TILs were more uniformly present in tumor pairs.

Conclusion

MPLCs are driven by different molecular events and often exhibit low TMB, low PD-L1, and a heterogeneous immune infiltration landscape. Specific genomic profiles are associated with TMB and the tumor immune microenvironmental landscape in MPLCs. Our findings can help to guide MPLCs diagnoses and to identify patient populations that may benefit from immunotherapy and targeted therapy.

Surgical outcomes of one-stage resection for synchronous multiple primary lung adenocarcinomas with no less than three lesions

Background

More and more synchronous multiple primary lung adenocarcinomas (SMPLA) have been diagnosed and surgical treatment has become the mainstay of treatment for them, but there are few reports on the surgical outcome of patients with ≥ 3 lesions who underwent surgical resection. Therefore, we summarized and analyzed the clinical characteristics and surgical outcomes of these patients, hoping to provide some experience in the diagnosis and treatment.

Methods

Clinical characteristics and treatment outcomes of patients with ≥ 3 lesions who have been diagnosed as SMPLA and underwent surgical resection in our hospital from March 2015 to July 2019 were retrospectively reviewed.

Results

Twenty-eight patients, 20 females and 8 males, with a mean age of 57.7 ± 5.69 (45–76) years, were finally included. A total of 95 lesions, 86.4% were ground-glass opacity (GGO) lesions (pure-GGO,45.3%; mixed-GGO,41.1%); 51 lesions had EGFR mutations and the mutation rate of invasive adenocarcinoma was significantly higher than that of other pathological subtypes (P < 0.001); the mutation rate of mGGO was also significantly higher than that of pGGO and solid nodule (SN) (P < 0.05). Four and 24 patients respectively underwent bilateral and unilateral surgical resection. The surgical procedure was mainly sublobar resection, and no severe postoperative complications or deaths occurred. After a median follow-up time of 32.2 months, the rates of overall survival and disease-free survival at 3 years were 94.7% and 88.9%, respectively.

Conclusions

For SMPLA with ≥ 3 lesions, one-stage resection may be safe and feasible, and surgical procedure was mainly sublobar resection as far as possible, which can yield satisfactory prognosis. EGFR mutation testing should be used routinely in the diagnosis and treatment of patients with SMPLA, especially in the presence of mGGO and invasive adenocarcinoma.

Guiding Principles in the Management of Synchronous and Metachronous Primary Non-Small Cell Lung Cancer

Multiple lung cancers can be found simultaneously, with incidence ranging from 1% to 8%. Documentation of more than 1 pulmonary lesion can be challenging, because these solid, ground-glass, or mixed-density tumors may represent multicentric malignant disease or intrapulmonary metastases. If mediastinal nodal and distant deposits are excluded, surgery should be contemplated. After surgical treatment of lung cancer, patients should be followed closely for an undetermined period of time. Good clinical judgment is of outmost importance in deciding which individuals will benefit from those surgical interventions and which are candidates for alternate therapies. Every case should be discussed in a multidisciplinary meeting.

Second pulmonary resection for a second primary lung cancer: analysis of morbidity and survival

OBJECTIVES

Evaluating morbidity and survival of patients operated on for a second primary non-small-cell lung cancer (NSCLC).

METHODS

Retrospective collection of data from patients operated on for a second NSCLC between 2009 and 2018.

RESULTS

Fifty-two patients met the inclusion criteria. At the time of second pulmonary resection, the median time between the 2 surgeries was 25 months (5-44.5 months). Patients' median age was 65 years (61-68 years). Median tumour size was 16 mm (10-22 mm). Thoracoscopy was used in 75% of cases. The resection was a pneumonectomy (n = 1), bilobectomy (n = 1), lobectomy (n = 15), segmentectomy (n = 32) or wedge resection (n = 3). The length of stay was 7 days (5-9 days). Mortality was null and morbidity was 36.5%, mainly from grade I-II complications according to the Clavien-Dindo classification. The median follow-up was 28 months (13-50 months). The median overall survival was 67 months (95% confidence interval 60.8-73.1 months). Survival at 5 years and specific survival were 71.1% and 67.7%, respectively.

CONCLUSIONS

A second surgical resection of either synchronous or metachronous NSCLC has a morbidity that is not superior to the morbidity of the first operation. The new tumour is usually diagnosed at an early stage. An anatomical sublobar resection is most likely the best compromise. It might also be considered for the first operation when there is a suspicious synchronous lesion that may require surgery at a later stage.

Therapeutic method for early-stage second primary non-small lung cancer: analysis of a population-based database

BACKGROUND

Early-stage non-small lung cancer patients may survive long enough to develop second primary lung cancers. However, few studies have accurately described the therapeutic method, evaluation or prognostic factors for long-term survival in this complex clinical scenario.

METHODS

Patients who had first and second primary non-small lung cancer in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were evaluated. Patients were included when their tumors were pathologically diagnosed as non-small lung cancer and in the early-stage (less than 3 cm and with no lymph node metastasis). Therapeutic methods were categorized as lobectomy, sublobectomy or no surgery. The influence of different therapeutic methods on the overall survival rate was compared.

RESULTS

For the first primary tumor, patients who underwent lobectomy achieved superior survival benefits compared with patients who underwent sublobectomy. For the second primary tumor, long-term survival was similar in patients who underwent lobectomy and those who underwent sublobectomy treatment. The multivariate analysis indicated that age, disease-free time interval, sex, and first and second types of surgery were independent prognostic factors for long-term survival. Our results showed that the 5-year overall survival rate was 91.9% when the disease-free interval exceeded 24 months.

CONCLUSION

Lobectomy for the first primary tumor followed by sublobectomy for the second primary tumor may be a beneficial therapeutic method for patients. If the disease-free interval exceeds 24 months, the second primary tumor will have no influence on the natural course for patients diagnosed with a first primary non-small lung cancer.

Tumor microenvironment disparity in multiple primary lung cancers: Impact of non-intrinsic factors, histological subtypes, and genetic aberrations

•

Tumor microenvironment (TME) was compared among multiple primary lung cancers (MPLCs).

•

Sex and smoking status concomitantly impacted PD-L1 expression in paired tumors.

•

EGFR mutations were independently associated with PD-L1 expression.

•

KRAS mutations altered the TMEs according to the types of co-mutations.

•

The number of FOXP3-positive t cells reflected histological subtypes.

Introduction

Multiple primary lung cancers (MPLCs) occur in common carcinogenetic risks such as lifestyle, biological aging, immune responses, hormones, and metabolism. Although MPLCs harbor various genetic profiles within the same individuals, differences in the tumor microenvironment (TME) are unclear. We investigated the impact of genetic aberrations, non-intrinsic factors, and pathological subtypes on tumor immunity.

Materials and Methods

In total, 73 surgically resected specimens from 32 patients with MPLC were analyzed. PD-L1 expression in tumor cells (TCs) and immune cells (ICs), CD3-positive tumor-infiltrating lymphocytes (TILs), CD8/CD3 ratios, and FOXP3-positive TILs that compose TMEs were evaluated by immunohistochemistry and classified on a score of 0–2. 38 tumors were sequenced for somatic mutations in 409 cancer-associated genes.

Results

Females and never or light smokers had a higher incidence of PD-L1-negative tumors and a higher concordance rate. PD-L1 positivity in TCs and ICs was significantly less frequent in EGFR-mutated than in wild-type tumors. Differences in the score of TMEs were observed between the KRAS-mutated-only tumor and the KRAS and TP53-co-mutated tumors, and between the KRAS-mutated-only tumor and the KRAS and STK11-co-mutated tumors. Significantly more FOXP3-high TILs were observed in invasive pathological subtypes than in non-invasive ones.

Conclusion

Comparing TMEs among MPLCs revealed that non-smokers or light smokers and females were unlikely to express PD-L1 regardless of tumor site and confirmed that the EGFR mutations and co-occurring KRAS and STK11 or TP53 mutations were associated with TME. Pathological subtypes may impact the efficacy of immune therapy due to their potential correlations with regulatory T cells.

Repeat pulmonary resection for lung malignancies does not affect the postoperative complications: a retrospective study

BACKGROUND

Although repeat pulmonary resection (RPR) for multiple lung cancer has been performed for non-small cell lung cancer and metastatic lung tumor, with the prognostic benefit detailed in several reports, the risk of RPR has not been well analyzed.

METHODS

Patients with lung malignancies who underwent complete resection at Kanazawa Medical University between January 2010 and October 2019 were analyzed. The relationship between postoperative complications and preoperative and perioperative factors was analyzed. Postoperative complications were categorized into five grades according to the Clavien-Dindo classification system.

RESULTS

A total of 41 patients who were received RPR were enrolled in this study. Primary lung tumor was found in 31 patients, and metastatic lung tumor was found in 10 patients. The postoperative complication rate of the first operation was 29%, and that of the second operation was 29%. While there were no significant factors for an increased incidence of postoperative complication in a multivariate analysis, an operation time over 2 h at the second operation tended to affect the incidence of postoperative complication (p = 0.06). Furthermore, the operation time was significantly longer (p = 0.02) and wound length tended to be longer (p = 0.07) in the ipsilateral group than in the contralateral group. The rate of postoperative complications and the length of the postoperative hospital stay were not significantly different between the two groups.

CONCLUSION

RPR is safely feasible and is not associated with an increased rate of postoperative complications, even on the ipsilateral side.

Mutational landscape of multiple primary lung cancers and its correlation with non-intrinsic risk factors

Multiple primary lung cancers (MPLCs) harbour various genetic profiles among the tumours, even from individuals with same non-intrinsic risk factors. Paired mutational analyses were performed to obtain a census of mutational events in MPLC and assess their relationship with non-intrinsic risk factors. Thirty-eight surgical specimens from 17 patients diagnosed as MPLC were used. Extracted DNAs were sequenced for somatic mutations in 409 cancer-associated genes from a comprehensive cancer panel. We statistically analysed the correlation between each driver mutation frequency and non-intrinsic risk factors using Fisher's exact test, and whether genetic mutations occurred concomitantly or randomly in MPLC using an exact test. Comprehensive genetic analyses suggested different mutation profiles in tumours within the same individuals, with some exceptions. EGFR, KRAS, TP53, or PARP1 mutations were concomitantly detected in some MPLC cases. EGFR mutations were significantly more frequent in never or light smokers and females. Concomitant EGFR or KRAS mutations in MPLCs were significantly more frequent than expected by chance (P = .0023 and .0049, respectively) suggesting a more prominent role of non-intrinsic risk factors in EGFR and KRAS mutations than other mutations, which occurred more randomly. Concomitant EGFR or KRAS mutations were particularly prominent in never or light smokers and males.

A multidisciplinary approach for the differential diagnosis between multiple primary lung adenocarcinomas and intrapulmonary metastases

PURPOSE

The distinction between multiple primary lung cancers (MPLCs) and intrapulmonary metastases has a significant impact on tumor staging and therapeutic choices. Several criteria have been proposed to solve this diagnostic issue, but a definitive consensus is still missing. We tested the efficacy of a combined clinical, histopathological and molecular ("real world") approach for the correct classification of multiple lung tumors in a selected cohort of patients.

METHODS

24 multiple lung tumors with a diagnosis of adenocarcinoma from 10 patients were retrospectively reviewed. Radiological, pathological and clinical information, including follow-up, were integrated with molecular profiling via a routine multigene panel sequencing.

RESULTS

Comprehensive histologic assessment revealed readily distinguishable histologic patterns between multiple tumors suggesting unrelated lesions in 7 cases, in agreement with clinical, radiological and molecular data, thus leading to final diagnosis of MPLCs. In the remaining 3 cases, the differential diagnosis between MPLCs and intrapulmonary metastases was challenging, since the histologic features of the lesions were similar or identical. The final interpretation (2 MPLCs and 1 most likely intrapulmonary metastases) was reached thanks to the integration of all available data, and was confirmed by follow-up.

CONCLUSIONS

A multidisciplinary approach including a routinely affordable multigene panel sequencing is a useful tool to discriminate MPLCs from intrapulmonary metastases in multiple lung nodules sharing the adenocarcinoma histotype.

Synchronous Multiple Lung Cancers with Lymph Node Metastasis and Different EGFR Mutations: Intrapulmonary Metastasis or Multiple Primary Lung Cancers?

Background

There is no consensus on whether patients with synchronous multiple lung cancers (SMLC) who present with lymph node metastasis (LNM) but whose epidermal growth factor receptor (EGFR) mutations are different are considered to have intrapulmonary metastases or multiple primary lung cancers. Few studies on these patients have been reported.

Methods

The electronic medical records of patients with surgically resected multiple lung cancers between February 2016 and July 2019 were retrospectively reviewed, focusing on the clinical characteristics and prognosis of patients with LNM and different EGFR mutations.

Results

A total of 125 patients were diagnosed with SMLC, and only 8 patients had LNM and different EGFR mutations. Their mean age was 61.43 ± 8.08 years (range 47–69 years). EGFR detection suggested that 4 patients had completely different mutation types, and 4 patients had mutations in only 1 tumor. Only 1 of the 17 total lesions was squamous cell carcinoma, the rest were adenocarcinoma. All patients underwent adjuvant therapy after surgery. Except for 1 patient who underwent chemotherapy, the rest received tyrosine kinase inhibitor-targeted therapy. As at 15 October 2020, the average follow-up time was 28.68 ± 10.74 months (range 10.5–40.5 months), and all patients were alive except 1 who died from extensive pleural metastasis.

Conclusion

The current study highlights the clinical importance of EGFR detection in SMLC, especially in patients with LNM. SMLC with LNM and different EGFR mutations should be considered multiple primary lung cancers rather than intrapulmonary metastases, and comprehensive treatment based on surgery may be preferable in these patients due to a good prognosis.

Management for Residual Ground-Glass Opacity Lesions After Resection of Main Tumor in Multifocal Lung Cancer: A Case Report and Literature Review

There are increasing numbers of synchronous multiple primary lung cancer (SMPLC) patients in clinical practice, with most lesions presenting as ground-glass opacity (GGO). For SMPLC patients, surgical resection should be a prior option for all lesions suspected of being malignant, if medically and technically feasible. However, it is frequently a dilemma for the management of residual GGO lesions that were unresected simultaneously with the main tumor in SMPLC patients. We report a case of SMPLC, in which the patient underwent surgical resection of the major lesion with EGFR mutation and then received compelling EGFR-TKI treatment for one enlarging residual GGO lesion after 12 months since operation. Furthermore, a comprehensive literature review about the risk for the progress of GGOs unresected simultaneously with the main lesion and the management of these residual GGOs was also summarized. With the treatment of EGFR-TKI gefitinib for 3 months, the biggest residual GGO lesion (more than 10mm) achieved a complete response (CR), three lesions reduced in size, and the other three lesions remained stable in this case. Surgical resection for major lesion and EGFR-TKI treatment on unresected GGOs might bring favorable outcome for patients with EGFR-mutated multifocal lung cancer. This strategy is safe and effective, which could be a promising therapeutic approach for unresectable GGO lesions in EGFR-mutated SMPLC patients after primary surgery. Notably, folate receptor-positive circulating tumor cell (FR⁺-CTC) for therapeutic monitoring was more sensitive for GGO-featured lung adenocarcinoma than serum markers.

Characteristics and prognosis of synchronous multiple primary lung cancer after surgical treatment: A systematic review and meta-analysis of current evidence

Background

This study aims to quantitatively summary the characteristics of synchronous multiple primary lung cancer (sMPLC), postoperative mortality, long‐term prognosis, and prognostic effects of potential clinical parameters in patients with sMPLC after surgery.

Methods

PubMed and Embase databases were systematically searched to identify studies that explored the prognosis of patients with sMPLC after surgery.

Results

Fifty‐two studies with 3486 participants were included, and clinical characteristics were quantitatively summarized. The pooled proportion of sMPLC in lung cancer was 2.0% (95%CI, 1.6%–2.5%) with an increasing trend over time, and postoperative mortality was 1.4% (95%CI, 0.5%–2.7%) with a decreasing trend over time. The 5‐year survival rate was 44.9% (95%CI, 37.4%–52.6%) and all long‐term survival rates showed increasing trends over time. Poor long‐term prognosis was observed in both limited resection (HR = 1.357, 95%CI, 1.047–1.759, p = 0.0210) and pneumonectomy (HR = 2.643, 95%CI, 1.539–4.541, p = 0.0004) by comparison of anatomical resection. Other clinical parameters of age, gender, smoking status, FEV1, and lymph node metastasis significantly impacted the long‐term prognosis (all p < 0.05).

Conclusions

The proportion of sMPLC in lung cancer and 5‐year survival rate are increasing, while postoperative mortality is decreasing trend over time. Lobectomy should be preferred, while pneumonectomy should be avoided for sMPLC. Age, gender, FEV1, smoking, tumor size, surgical methods, and lymph node status are prognostic factors for sMPLC. Considering the heterogeneity and publication bias, these findings should be treated with caution.

Surgical Prognosis of Synchronous Multiple Primary Lung Cancer: Systematic Review and Meta-Analysis

BACKGROUND

We evaluated the long-term prognosis of synchronous multiple primary lung cancer (SMPLC) patients after surgical treatment and explored prognostic factors for overall survival (OS).

MATERIALS AND METHODS

A systematic review and meta-analysis was performed regarding the surgical prognosis of SMPLC. A literature search was performed using online databases. All studies were rigorously categorized following the 8th edition of the tumor, node, metastasis classification (TNM) staging rules for multiple lung cancers: SMPLC and multifocal ground-glass/lepidic (GG/L) lung cancers. Five-year OS after surgery was pooled, and hazard ratios (HRs) for prognostic factors were synthesized. Specific subgroup analysis and sensitivity analysis were conducted (PROSPERO registration CRD42019142420).

RESULTS

An analysis of 26 studies including 1788 patients was performed. The pooled 5-year OS was 45% (95% confidence interval [CI], 37-53) of true SMPLC patients and 62% (95% CI, 57-67) of patients with pathologic stage I disease, which was different from the 5-year OS of 93% (95% CI, 85-100) of patients with multifocal GG/L lung cancers. Poor prognostic factors for SMPLC were lymph node metastasis (HR = 2.36; 95% CI, 1.75-3.20; P < .001) and pneumonectomy (HR = 2.96; 95% CI, 1.36-6.45; P = .006], whereas histology (HR = 1.11; 95% CI, 0.82-1.50; P = .508), laterality (HR = 1.16; 95% CI, 0.93-1.44, P = .190), sublobar resection (HR = 1.29; 95% CI, 0.90-1.84; P = .159), and adjuvant therapy (HR = 1.07; 95% CI, 0.64-1.80; P = .791) were not found to influence the outcome.

CONCLUSION

The long-term prognosis of SMPLC patients after surgery is acceptable, especially in patients with early-stage disease. Sublobar resection can be applied, although pneumonectomy should be avoided. Advanced criteria are needed to diagnose SMPLC and distinguish it from multifocal GG/L lung cancer to perform accurate surgical evaluation.

Multiple Primary Lung Cancers: A New Challenge in the Era of Precision Medicine

With the widespread implementation of lung cancer screening, more and more patients are being diagnosed with multiple primary lung cancers (MPLCs). In the era of precision medicine, many controversies remain in differentiating MPLCs from intrapulmonary metastasis and the optimum treatment choice, especially in patients exhibiting similar histology. In this review, we summarize common diagnostic criteria and novel discrimination methods with a special emphasis on the emerging value of broad panel next-generation sequencing (NGS) for the diagnosis of MPLCs. We then discuss current advances regarding therapeutic approaches for MPLCs. Radical surgery is the main treatment modality, while stereotactic body radiotherapy (SBRT) is safe and feasible for early-stage MPLC patients with inoperable tumors. In addition, immunotherapy and targeted therapy, particularly epidermal growth factor receptor-tyrosine kinase inhibitors, are emerging therapeutic strategies that are still in their infancy. Characteristics of both genomic profiles and tumor microenvironment are currently being evaluated but warrant further exploration to facilitate the application of targeted systematic therapies in MPLC patients.

Distinguishing multiple lung primaries from intra-pulmonary metastases and treatment implications

INTRODUCTION

The distinction between multiple primary lung cancers and intra-pulmonary metastases has been extensively investigated because of its important clinical and therapeutic implications.

AREAS COVERED

Rapidly improving imaging technology and genomic analysis has led to a finer discrimination between multiple primary lung tumors and pulmonary metastases. However, over the past few decades, standardized criteria for the identification of multiple lung tumors have been lacking. Therefore, in 2017 a multidisciplinary international committee composed of the Union for International Cancer Control (UICC), American Joint Committee on Cancer (AJCC) and International Association for the Study of Lung Cancer (IASLC) addressed this problem when drawing up the 8th edition of TMN stage classification, that now represents a specific consensus on this topic. The most advanced diagnostic strategies associated with screening allow for the detection of early stage synchronous lung cancers.

EXPERT OPINION

Although diagnostic confirmation relies on pathologic and clinical examination, new molecular analyses help in the discrimination between primary and secondary tumors. The treatment of multiple primary lung tumors remains, whenever possible, a local treatment based on surgical resection, providing the absence of distant or local (lymph node) metastases.

Synchronous multiple primary lung cancers with shared EGFR mutation but differential imaging findings and pathological subtypes: A case report

Lung cancer is a leading cause of cancer mortality worldwide. As the incidence of lung cancer increases in recent years, the number of patients diagnosed with synchronous multiple primary lung cancers (SMPLC) is also rising. SMPLC diagnosis is often made based on the clinical course, imaging findings, and histologic and molecular features. Standard lobectomy is the main therapeutic modality for SMPLC. Because maximum retention of lung function is essential, sublobectomy is also a commonly used surgical strategy when appropriate. The question is how to optimize the sequence of lobectomy and sublobectomy for patients with SMPLC. Thoracoscope lobectomy for the primary lesion plus sublobectomy for the secondary lesions is the most commonly used approach. Here we present a case of SMPLC with sublobectomy followed by lobectomy.

Lymph Node Examination for Stage I Second Primary Lung Cancer Patients Who Received Second Surgical Treatment

PURPOSE

This study aims to investigate the effect of lymph node examination on overall survival (OS) and lung cancer-specific survival (LCSS) in stage I second primary lung cancer (SPLC) patients who underwent second pulmonary resection.

PATIENTS AND METHODS

We conducted a retrospective study with the Surveillance, Epidemiology, and End Results (SEER) database to identify stage I SPLC patients who received surgery from 1998 to 2015. The Kaplan-Meier method with landmark analysis and multivariable Cox regression analysis were performed to evaluate the prognostic value of lymph node examination.

RESULTS

A total of 842 patients from the SEER database with stage I SPLC who underwent a second surgical treatment were included. The 5-year survival rate was 54.8% for the whole cohort. Multivariable analysis revealed that the number of lymph nodes examined (LNE) was associated with better OS and LCSS in SPLC patients after 12 months postoperatively. Patients with contralateral SPLC had significantly more nodes removed than those with ipsilateral SPLC. For contralateral SPLC, more than 10 LNE was correlated with improved long-term survival outcomes. Ipsilateral SPLC patients benefited from 4 or more LNE. However, the current analysis did not show a significant survival benefit from lymph node examination within 12 months after surgery.

CONCLUSIONS

For stage I SPLC patients who received surgical treatment after initial resection, an adequate number of LNE would improve both OS and LCSS. We recommend more than 10 LNE for contralateral SPLC and at least 4 LNE for ipsilateral SPLC.

Synchronous Multiple Primary Cancers of the Lung: The Rare Association of Non-Small Cell Carcinoma With a Carcinoid Tumor

A 68-year-old female patient diagnosed with lung cancer in the left upper lobe with associated mediastinal adenopathy. The cancer was pathologically diagnosed as stage pT1bN0 typical carcinoid. Investigation of the mediastinal lymph nodes revealed an isolated metastatic non-small cell squamous cell carcinoma (NSCLC). A primary NSCLC was not found. The patient underwent successful surgical resection of both synchronous tumors, with no residual disease or recurrence. This case not only expands the histological field of combined neuroendocrine tumors, but it also highlights the importance of distinguishing various tumor types for disease treatment and prognosis.

Increased reporting but decreased mortality associated with adverse events in patients undergoing lung cancer surgery: Competing forces in an era of heightened focus on care quality?

INTRODUCTION

Advances in surgical techniques have improved clinical outcomes and decreased complications. At the same time, heightened attention to care quality has resulted in increased identification of hospital-acquired adverse events. We evaluated these divergent effects on the reported safety of lung cancer resection.

METHODS AND MATERIALS

We analyzed hospital-acquired adverse events in patients undergoing lung cancer resection using the National Hospital Discharge Survey (NHDS) database from 2001-2010. Demographics, diagnoses, and procedures data were abstracted using ICD-9 codes. We used the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicators (PSI) to identify hospital-acquired adverse events. Weighted analyses were performed using t-tests and chi-square.

RESULTS

A total of 302,444 hospitalizations for lung cancer resection and were included in the analysis. Incidence of PSI increased over time (28% in 2001-2002 vs 34% in 2009-2010; P<0.001). Those with one or more PSI had increased in-hospital mortality (aOR = 11.1; 95% CI, 4.7-26.1; P<0.001) and prolonged hospitalization (12.5 vs 7.8 days; P<0.001). However, among those with PSI, in-hospital mortality decreased over time, from 17% in 2001-2002 to 2% in 2009-2010.

CONCLUSIONS

In a recent ten-year period, documented rates of adverse events associated with lung cancer resection increased. Despite this increase in safety events, we observed that mortality decreased. Because such metrics may be incorporated into hospital rankings and reimbursement considerations, adverse event coding consistency and content merit further evaluation.

Extended resections for the treatment of patients with T4 stage IIIA non-small cell lung cancer (NSCLC) (T4N0-1M0) with or without cardiopulmonary bypass: a 15-year two-center experience

Background

Stage IIIA non-small cell lung cancer (NSCLC) is a heterogeneous group of patients, often requiring variable and individualized approaches. The dilemma to operate or not frequently arises, since more than 75% of the cases of NSCLC are diagnosed in advanced stages (IIIA). The main objective of this study was to assess whether the benefits outweigh surgical risks for the T₄N_0-1M₀ subgroup.

Methods

Data from 857 patients with locally advanced T4 NSCLC were retrospectively collected from two different institutions, between 2002 and 2017. Clinical data that were retrieved and analyzed, included demographics, comorbidities, surgical details, neoadjuvant or/and adjuvant therapy and postoperative complications.

Results

Twelve patients were in the cardiopulmonary bypass (CPB) group and thirty in the non-CPB. The most common types of lung cancer were squamous cell carcinoma (50.0%) and adenocarcinoma (35.7%). The most frequent invasion of the tumor was seen in main pulmonary artery and the superior vena cava. Significantly more patients of the CPB group underwent pneumonectomy as their primary lung resection (P=0.006). In all patients R0 resection was achieved according to histological reports. The overall 5-year survival was 60%, while the median overall survival was 22.5 months. Analysis revealed that patient age (P=0.027), preoperative chronic obstructive pulmonary disease (COPD) (P=0.001), tumor size (4.0 vs. 6.0 cm) (P=0.001), postoperative respiratory dysfunction (P=0.001) and postoperative atelectasis (P=0.036) are possible independent variables that are significantly correlated with patient outcome.

Conclusions

We suggest that in patients with stage IIIA/T4 NSCLC, complete resection of the T4 tumor, although challenging, can be performed in highly selected patients. Such an approach seems to result in improved long-term survival. More specific studies on this area of NSCLC probably will further enlighten this field, and may result in even better outcomes, as advanced systemic perioperative approaches such as modern chemotherapy, immunotherapy and improvements in radiation therapy have been incorporated in daily practice.

Multiple primary lung cancer: a rising challenge

With the use of high-resolution chest imaging system and lung cancer screening program, patients with multiple primary lung cancers (MPLCs) are becoming a growing population in clinical practice worldwide. The diagnostic criteria for MPLCs has been established and modified by three major lung cancer research institutes. However, due to the fact that the differential diagnosis between MPLCs and a recurrence, metastatic, or satellite lesion arising from the original lesion remains ambiguous and confusing, there is still insufficient evidence to support a uniform guideline. Newly developed molecular and genomic methods have the potential to better define the relationship among multiple lesions and bring the possibility of targeted therapy. Surgical resection remains the first choice for the treatment of MPLCs and detailed strategy should be carefully planned taking characteristics of the tumor and status of patients into consideration. For those who are intolerant to surgery, a new technology called stereotactic body radiation therapy (SBRT) is now an optional therapeutic strategy. Furthermore, multiple GGOs are unique MPLCs that need special attentions in the clinical practice.

Electromagnetic navigation bronchoscopic dye marking for localization of small subsolid nodules: Retrospective observational study

Thoracoscopic resection of small subsolid nodules is challenging and requires preoperative localization. We investigated the efficacy, safety, and factors affecting accuracy in localizing pulmonary nodules with electromagnetic navigation bronchoscopy (ENB)-guided dye marking.Patients with small subsolid nodule(s) who underwent thoracoscopic resection after ENB-guided dye marking were retrospectively reviewed. Dye marking was performed at the nearest pleura and the localized nodule(s) was resected thoracoscopically. Efficacy was evaluated by success rates of dye marking and resection of nodules. Navigation accuracy was represented by target distance, which was the closest distance between target and the tip of locatable guide. Factors affecting target distance were evaluated by linear regression analyses.Twenty-nine ENB-guided dye markings were done for 24 nodules in 20 patients. The success rate of the dye marking and nodule localization were 93.1% (27/29) and 95.8% (23/24), respectively. Twenty-three nodules were completely resected thoracoscopically without conversion. There were no ENB-related complications: pneumothorax or bronchopulmonary hemorrhage. Nine targets were in the upper, 14 in the middle, and 6 in the lower zone. Even though navigation time was longer in the upper zone, target distance showed no significant inter-zone difference. Approach angle was the only significant predictor for target distance (0-45°, estimate = -1.24, P = .01; 45-90°, estimate = -1.26, P = .006; reference = ≥90°).Localization with ENB-guided dye marking is effective and safe for thoracoscopic resection of small subsolid nodules. For better performance, a pathway with smaller approach angle (<90°) should be selected to increase the navigation accuracy.

Adenocarcinoma of Lung and Bronchial Carcinoid Presenting as Double Synchronous Primary Lung Cancer: A Case Report and Review of Literature

Recent advances in imaging techniques led to an increase in the incidence of synchronous and metachronous primary lung cancers due to early detection. Management of these patients is challenging and prognosis depends on the stage of the tumor at initial diagnosis and histological type. A 68-year-old African American male patient with medical history of hypertension and diabetes mellitus presented to our emergency department with right sided chest pain, worsening dyspnea and dry cough of 2-week duration. He also reported significant weight loss and was a smoker with 25 pack-years smoking history. Chest radiology showed a large right pleural effusion. Subsequent thoracentesis and fluid analysis revealed a lymphocytic exudate. Patient underwent bronchoscopy with findings of an endobronchial lesion in the left lower bronchus. Microscopic analysis of the biopsy specimen showed a well differentiated carcinoid. It was decided to proceed with VATS and pleural biopsy as part of workup for unexplained exudative pleural effusion. Multiple pleural nodules were detected during the procedure and biopsy of these nodules revealed adenocarcinoma of lung. He was evaluated by Oncology and underwent palliative chemotherapy. The association of carcinoid with adenocarcinoma of lung was infrequently reported in the past. This case also highlights the importance of additional diagnostic workup for primary when the diagnosed malignancy does not explain the clinical presentation.

Synchronous primary lung adenocarcinomas harboring distinct MET Exon 14 splice site mutations

When a patient is found to have multiple lung tumors, distinguishing whether they represent metastatic nodules or separate primary cancers is crucial for staging and therapy. We report the case of a 79-year-old patient with two surgically resected synchronous left upper lobe adenocarcinomas initially pathologically staged as T3 (IIB), indicating adjuvant chemotherapy should be recommended. However, the tumors appeared radiographically distinct, so next-generation sequencing was performed on each nodule. Each tumor harbored a different mesenchymal-to-epithelial transition (MET) exon 14 skipping mutation, an emerging targetable mutation, suggestive of distinct clonality. While the in frame protein deletion was the same in each tumor, the nucleotide base substitutions were different. Thus, the patient was down-staged to having two separate IA tumors, spared of adjuvant chemotherapy, and routine surveillance was recommended. This case highlights the utility of using molecular analysis in diagnosing and treating multifocal lung tumors, and the process of convergent molecular evolution toward a common oncogenic driver mutation. This is the first case of multiple synchronous lung tumors each harboring a distinct MET exon 14 splice site mutation.

[Synchronous Multiple Primary Lung Cancer Dignosed by Different Phenotype-genotype: A Case Report and Literature Review]

随着低剂量螺旋计算机断层扫描（computed tomography, CT）广泛应用于早期肺癌筛查，诊断出的双肺同时多发性病变的病例数逐年增多，且大多数病例最后证实为同时性多原发肺癌（synchronous multiple primary lung cancer, SMPLC）。既往研究结果显示SMPLC的发病率约为0.2%-8%（穿刺研究结果为3.5%-14%）。目前对于MPLC的诊断，大多依据Martini-Melamed的诊断标准：SMPLC：①肺癌部位各异，彼此孤立；②组织学类型不同；③组织学类型相同时，位于不同肺段、肺叶、不同侧肺，由不同的原位癌起源，肺癌共同的淋巴引流部位无癌肿，确立诊断时无肺外转移。异时性多原发肺癌（metachronous multiple primary lung cancer, MMPLC）：①组织学类型不同；②组织学类型相同时，无瘤间期至少2年，或均由不同的原位癌起源，或第二原发癌位于不同肺叶或不同侧肺时，肺癌共同的淋巴引流部位无癌肿，确立诊断时无肺外转移。而各个肿瘤具有独特的病理形态特征为诊断MPLC的要点。此后很多学者在这条标准的基础上进行了不断的修订与丰富，包括国际肺癌研究协会（International Association for the Study of Lung Cancer, IASLC）新版肺腺癌分类及表皮生长因子受体（epidermal growth factor receptor, EGFR）、K-ras基因突变等，这些内容的增加使多原发癌灶与转移灶的鉴别诊断标准更加合理准确，也同时说明对于MPLC的各个病灶分别进行基因检测具有重要的鉴别和治疗意义。现将我院胸外科术后病理证实为不同组织亚型、不同基因型的同时性四原发肺癌患者诊治情况报道如下。

Histopathologic and molecular approach to staging of multiple lung nodules

Distinguishing multiple primary lung cancers from intrapulmonary metastases in patients with synchronous multifocal lung adenocarcinomas can be challenging. The most recent 8th edition American Joint Committee on Cancer staging manual (AJCC staging manual) distinguishes four disease patterns in patients with multiple lung nodules: (I) two or more distinct and histologically different masses (considered unrelated and staged as individual cancers); (II) multiple ground-glass or part-solid nodules, histologically of with lepidic growth pattern (considered separate tumors, T staged based on highest T stage lesion); (III) patchy areas of ground-glass and consolidations, histologically often invasive mucinous adenocarcinomas (considered single tumor with diffuse "pneumonic-type" involvement); and (IV) separate nodules with the same histologic features based on comprehensive histologic subtyping (considered intrapulmonary metastases). Histologic and molecular features, in conjunction with clinical and radiological information, can all be tools to assist with staging of multiple nodules. Histologic features of adenocarcinomas are best characterized using comprehensive histologic subtyping (percentage of lepidic, acinar, solid, papillary and micropapillary pattern). Genomic alterations are commonly assessed using fluorescence in-situ hybridization and next generation sequencing (NGS). The AJCC considers exactly matching breakpoints by comparative genomic hybridization (CGH) as the only evidence for intrapulmonary metastases, and clearly different histologic types or subtypes as the only evidence for separate primary tumors. Similar histologic subtypes or the same biomarker pattern are considered merely relative arguments in favor of a single tumor source. When assessing multifocal lung cancer, pathologists should consider, and carefully weigh the importance of, molecular testing results in addition to the tumor's histologic features. For many cases encountered in routine clinical practice, absolute certainty cannot be reached as to whether they represent multiple primary cancers or intrapulmonary metastases. Classification of difficult cases often benefits from multidisciplinary discussion.

Triple synchronous primary lung cancer: a case report and review of the literature

Background

Multiple primary lung cancer may present in synchronous or metachronous form. Synchronous multiple primary lung cancer is defined as multiple lung lesions that develop at the same time, whereas metachronous multiple primary lung cancer describes multiple lung lesions that develop at different times, typically following treatment of the primary lung cancer. Patients with previously treated lung cancer are at risk for developing metachronous lung cancer, but with the success of computed tomography and positron emission tomography, the ability to detect both synchronous and metachronous lung cancer has increased.

Case presentation

We present a case of a 63-year-old Hispanic man who came to our hospital for evaluation of chest pain, dry cough, and weight loss. He had recently been diagnosed with adenocarcinoma in the right upper lobe, with a poorly differentiated carcinoma favoring squamous cell cancer based on bronchoalveolar lavage of the right lower lobe for which treatment was started. Later, bronchoscopy incidentally revealed the patient to have an endobronchial lesion that turned out to be mixed small and large cell neuroendocrine lung cancer. Our patient had triple synchronous primary lung cancers that histologically were variant primary cancers.

Conclusions

Triple synchronous primary lung cancer management continues to be a challenge. Our patient’s case suggests that multiple primary lung cancers may still occur at a greater rate than can be detected by high-resolution computed tomography.

The case of synchronous occurrence of primary adenocarcinoma and squamous cell carcinoma in the same lobe of the lung

Synchronous occurrence of multiple lung cancers in the same lobe of the lung is very rare. Most of the tumors diagnosed in this way have the same histologic type. With imaging methods it is difficult to determine if the multiple lung lesions present hematogenous spread of lung cancer (or cancer from other origin) or these lesions present the second primary lung cancer. We report a rare and unusual case of synchronous occurrence of primary adenocarcinoma and squamous cell carcinoma in the same lobe of the lung. Our case demonstrates that in case of synchronous occurrence of multiple lung lesions each lesion should be sampled and histologic type of every lesion should be determined so the further treatment can be planned accordingly.

Use of Oncogenic Driver Mutations in Staging of Multiple Primary Lung Carcinomas: A Single-Center Experience

OBJECTIVE

The staging of multiple pulmonary adenocarcinomas requires the distinction of intrapulmonary metastasis (IPM) from multiple primary lung cancers (MPLCs). This can be challenging in some patients, and the addition of data from oncogenic driver mutations in these tumors may be helpful in this determination.

METHODS

As a proof of principle, molecular driver results from primary tumors and their metastases in 45 patients were compared (cohort 1). Then, 69 patients with a total of 154 synchronous or metachronous lung carcinomas were identified, and the pathologic findings were compared with oncogenic driver mutation. Each patient was assigned a highest potential T or M category on the basis of clinical, histopathologic, and molecular findings (cohort 2).

RESULTS

The concordance rate of EGFR, KRAS, BRAF, and ALK receptor tyrosine kinase gene (ALK) mutations was 96% in cohort 1. In cohort 2, 36% of multiple same-lobe nodules were MPLCs, 40% were IPM, and 24% were noninformative by molecular findings. Of nodules with multiple lobe involvement, 81.5% were MPLCs and 7.4% were IPM, with 11% noninformative. Of metachronous tumors, 52.9% were MPLCs. Overall survival was 100% at 2 years, 95% at 3 years, and 80% at 4 years in patients with available follow-up.

CONCLUSIONS

Oncogenic driver mutations are concordant between primary tumors and metastasis. The largest proportion of MPLCs was seen in tumors of multiple lobes, but with a substantial proportion of MPLCs among single-lobe nodules and with metachronous tumors. Overall survival was higher than expected for the respective highest T or M category, which is in support of the high frequency of MPLC.

Linear EBUS-guided fiducial marker placement to guide radiotherapy for endobronchial, radiographically occult synchronous primary squamous cell carcinoma of the lung

Radiation therapy has emerged as a useful alternative therapy for patients with early-stage, non-resectable lung cancer. In patients whose malignancies are difficult to localize on computed tomography imaging, such therapy becomes difficult. Fiducial markers are frequently placed in peripheral pulmonary lesions to assist radiation therapy. Although placement of markers under linear endobronchial ultrasonography within mediastinal and hilar lymph nodes has been reported, no strategy has been described to assist radiotherapy of purely endobronchial tumors. We present a case of bilateral, unresectable, radiographically occult endobronchial squamous cell carcinoma treated with radiotherapy guided by fiducial markers placed under linear endobronchial ultrasonographic guidance. The patient subsequently underwent intensity-modified radiation therapy to both lesions with pathologic complete response. Linear endobronchial ultrasound is a promising tool for placement of markers to guide radiation therapy of these difficult-to-treat lesions.

Survival rate and prognostic factors of surgically resected clinically synchronous multiple primary non-small cell lung cancer and further differentiation from intrapulmonary metastasis

BACKGROUND

The diagnosis, staging, and therapeutic strategy for synchronous multiple primary non-small cell lung cancer (SMP-NSCLC) remain unclear. Distinguishing SMP-NSCLC from intrapulmonary metastasis is difficult but of great importance for selecting the surgical procedure and prognoses.

METHODS

Fifty-two patients diagnosed with SMP-NSCLC according to the modified Martini-Melamed criteria in the thoracic surgery department of the China-Japan Friendship Hospital from November 2004 to December 2015 were enrolled in this retrospective study. A total of 106 tumors were subjected to pathological examination. Close follow-up and survival analysis were performed.

RESULTS

The perioperative morbidity rate was 5.8%, with no cases of perioperative death. The overall 5-year survival rate was 40.6%, the cancer-specific 5-year survival rate was 54.5%, and the median survival time was 52 months. Older age (P=0.553), sex (P=0.600), smoking history (P=0.496), tumor distribution (P=0.461), video-assisted thoracoscopic surgery (VATS) (P=0.398), and adjuvant chemotherapy (P=0.078) did not affect survival. Preoperative percentage of forced expiratory volume in the first second (P=0.022), Charlson comorbidity index (P=0.034), surgical procedure (P=0.040), and highest pT stage (P=0.022) were independent risk factors in the multivariate analysis. Different pathological subtypes were identified in 13 of 18 cases of multiple adenocarcinomas. Different gene mutation types and correlations between tumors were identified through NGS in those with the same pathological subtype.

CONCLUSIONS

Postoperative survival rates in SMP-NSCLC were satisfactory. Non-radical resection might improve the prognosis for patients with a tolerable general condition and pulmonary function. Higher pT stage might result in poorer survival rates. Larger sample size and future study are still needed to identify the prognostic factors. Comprehensive histologic assessment and next generation sequencing (NGS) could be effective methods for screening SMP-NSCLC.

A case of three synchronous primary lung cancers within the same lung lobe

We present the case of a 74-year-old patient with three synchronous primary lung cancers within the same lung lobe. Computed tomography and positron emission tomography investigations revealed two suspicious nodular lesions in the upper lobe of the left lung. Fine-needle aspiration biopsy confirmed that one of the lesions was non-small cell lung cancer. The patient was qualified for surgical treatment, and left upper lobectomy plus lymphadenectomy was performed. Histopathological examination confirmed the presence of three primary cancers in the left lung: keratinizing squamous cell carcinoma, neuroendocrine carcinoma, and acinar adenocarcinoma, localized within the same lung lobe. The patient was classified as having stage T3N1M0 lung cancer (stage IIIA) according to the latest, 7^th edition of the TNM classification.