Incidence of Second Malignancy after Successful Treatment of Limited-Stage Small-Cell Lung Cancer and Its Effects on Survival

Clinical insights into small cell lung cancer: Tumor heterogeneity, diagnosis, therapy, and future directions

Small cell lung cancer (SCLC) is characterized by rapid growth and high metastatic capacity. It has strong epidemiologic and biologic links to tobacco carcinogens. Although the majority of SCLCs exhibit neuroendocrine features, an important subset of tumors lacks these properties. Genomic profiling of SCLC reveals genetic instability, almost universal inactivation of the tumor suppressor genes TP53 and RB1, and a high mutation burden. Because of early metastasis, only a small fraction of patients are amenable to curative-intent lung resection, and these individuals require adjuvant platinum-etoposide chemotherapy. Therefore, the vast majority of patients are currently being treated with chemoradiation with or without immunotherapy. In patients with disease confined to the chest, standard therapy includes thoracic radiotherapy and concurrent platinum-etoposide chemotherapy. Patients with metastatic (extensive-stage) disease are treated with a combination of platinum-etoposide chemotherapy plus immunotherapy with an anti-programmed death-ligand 1 monoclonal antibody. Although SCLC is initially very responsive to platinum-based chemotherapy, these responses are transient because of the development of drug resistance. In recent years, the authors have witnessed an accelerating pace of biologic insights into the disease, leading to the redefinition of the SCLC classification scheme. This emerging knowledge of SCLC molecular subtypes has the potential to define unique therapeutic vulnerabilities. Synthesizing these new discoveries with the current knowledge of SCLC biology and clinical management may lead to unprecedented advances in SCLC patient care. Here, the authors present an overview of multimodal clinical approaches in SCLC, with a special focus on illuminating how recent advancements in SCLC research could accelerate clinical development.

Risk Factors Associated with a Second Primary Lung Cancer in Patients with an Initial Primary Lung Cancer

Targeted surveillance strategies following initial primary lung cancer (IPLC) treatment are currently limited. One hundred twenty patients diagnosed with IPLC who did not develop second primary lung cancer (SPLC) were matched to 121 patients who developed SPLC. Our analysis found IPLC surgical resection increases SPLC emergence risk regardless of procedure type. Increased survival after IPLC resection warrants close SPLC monitoring.

Small-cell lung cancer

Small-cell lung cancer (SCLC) represents about 15% of all lung cancers and is marked by an exceptionally high proliferative rate, strong predilection for early metastasis and poor prognosis. SCLC is strongly associated with exposure to tobacco carcinogens. Most patients have metastatic disease at diagnosis, with only one-third having earlier-stage disease that is amenable to potentially curative multimodality therapy. Genomic profiling of SCLC reveals extensive chromosomal rearrangements and a high mutation burden, almost always including functional inactivation of the tumour suppressor genes TP53 and RB1. Analyses of both human SCLC and murine models have defined subtypes of disease based on the relative expression of dominant transcriptional regulators and have also revealed substantial intratumoural heterogeneity. Aspects of this heterogeneity have been implicated in tumour evolution, metastasis and acquired therapeutic resistance. Although clinical progress in SCLC treatment has been notoriously slow, a better understanding of the biology of disease has uncovered novel vulnerabilities that might be amenable to targeted therapeutic approaches. The recent introduction of immune checkpoint blockade into the treatment of patients with SCLC is offering new hope, with a small subset of patients deriving prolonged benefit. Strategies to direct targeted therapies to those patients who are most likely to respond and to extend the durable benefit of effective antitumour immunity to a greater fraction of patients are urgently needed and are now being actively explored.

Role of endothelin receptor type B (EDNRB) in lung adenocarcinoma

BACKGROUND

The five-year survival rate of lung adenocarcinoma patients (LUAD) is very low,and the methods of predicting survival are a great obstacle for LUAD therapies. Endothelin receptor type B (EDNRB) gene is associated with tumorigenesis. In this study, we aimed to evaluate the predictive value of EDNRB on LUAD.

METHODS

Survival analyses was performed to assess the correlation between EDNRB expression and survival of LUAD patients from the Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) datasets. Gene set enrichment analysis (GSEA) was conducted to illustrate possible biological functions of EDNRB. Laboratory methods were used to verify the function of EDNRB in LUAD.

RESULTS

The TCGA results showed that a low expression of EDNRB was found in LUAD patients which led to poor outcome and worse survival, compared with the high expression in GSEA results which suggested that expression of EDNRB might be associated with regulation of the ERK pathway. Laboratory results suggested that EDNRB could inhibit the proliferation and migration of LUAD H1299 cells.

CONCLUSIONS

EDNRB is a potential prognostic marker for LUAD patients and might exert its functions by regulating the ERK pathway in LUAD.

Extensive-disease small cell lung cancer, multiple relapses, five lines of therapy and more than 10-year survival

Small cell lung cancer (SCLC) accounts for nearly 18% of lung cancer cases. Most of the patients of SCLC are not surgical candidates, due to advanced stage at presentation hence only viable options are chemotherapy and radiotherapy. Long-term survival in SCLC is extremely rare due to relapses and comorbidities. Ten-year survival has never been reported in cases with extensive disease at presentation and history of relapses. Here we are describing a case of extensive disease SCLC who has survived multiple relapses and has received five lines of systemic therapy apart from radiation and palliative care. This case emphasises on the need of active and strict disease surveillance at each follow-up.

Resection of Early-Stage Second Primary Non-small Cell Lung Cancer After Small Cell Lung Cancer: A Population-Based Study

Introduction: A certain number of small cell lung cancer (SCLC) patients become long-term survivors after treatment, and they are at high risk to develop a second primary malignancy, including non-small cell lung cancer. However, the optimal management of early-stage second primary non-small cell lung cancer (SPLC) after SCLC remains unknown. This study aims to evaluate the survival benefits of surgery in these patients.

Methods: Patients with early-stage SPLC after SCLC were identified from the Surveillance, Epidemiology, and End Results database. Patients were balanced with propensity score matching (PSM). Overall survival (OS) and lung cancer-specific survival (CSS) were compared between non-surgery group and surgery group with the Kaplan–Meier method and Cox multivariate regressions.

Results: A total of 228 patients with early-stage SPLC after SCLC were identified. Surgery was associated with significantly improved OS and CSS in the multivariate Cox regression analysis (OS, 5-year survival: 41.2 vs. 11.6%, HR: 0.42, 95% CI: 0.31–0.59, P < 0.01; CSS, 5-year survival: 46.8 vs. 24.3%, HR: 0.53, 95% CI: 0.37–0.75, P < 0.01). However, no statistically significant survival difference was found between sublobar resection and lobectomy (OS, 5-year survival: 41.0 vs. 45.3%, P = 0.73; CSS, 5-year survival: 43.5 vs. 54.1%, P = 0.49). After 1:1 PSM, 162 patients were selected for further analysis, and surgery continued to demonstrate superior survival (OS, 5-year survival: 44.2 vs. 7.2%, HR: 0.48, 95% CI: 0.33–0.70, P < 0.01; CSS, 5-year survival: 48.0 vs. 20.6%, HR: 0.44, 95% CI: 0.42–0.97, P = 0.03).

Conclusion: The resection of early-stage SPLC after SCLC led to significantly improved OS and CSS and therefore should be considered whenever possible. Nevertheless, further randomized controlled trials are warranted to investigate the safety and effect of surgery in these patients.

Radiotherapy was associated with the lower incidence of metachronous second primary lung cancer

Our study aims to estimate the incidence of metachronous second primary lung cancer(SPLC) in initial primary lung cancer(IPLC) survivors and to determine whether radiotherapy affects the risk of metachronous SPLC in the first five years after the diagnosis of lung cancer. Incidence data of IPLC individuals who survived ≥2 years were obtained from SEER-18 database in 2004–2007. Joinpoint regression analysis and competing risk analysis were used to calculate the incidence of metachronous SPLC. Propensity score matching and decision analysis were available to estimate the effect of radiotherapy on metachronous SPLC. 264 of 11657 IPLC survivors with radiotherapy and 1090 of 24499 IPLC survivors without radiotherapy developed metachronous SPLC during 5-year follow-up, respectively. In joinpoint regression analysis, the 5-year incidence of metachronous SPLC in the radiotherapy group was lower than that in the nonradiotherapy group(2385 per 100,000 vs 4748 per 100,000, HR = 0.43,95% CI:0.39–0.47). Competing risk analysis showed that the survivors with radiotherapy were associated with the lower 5 year incidence of metachronous SPLC compared with those without radiotherapy(2.28% vs 4.47%, HR = 0.49,95% CI:0.43–0.57). Through propensity score matching, 4077 pairs of survivors were available to further study that radiotherapy potentially decreased the risk of developing metachronous SPLC with the adjustment of various factors(2.5% vs 3.3%, HR = 0.72, 95% CI:0.55–0.96). Decision analysis suggested that radiotherapy was a negative independent risk factor of metachronous SPLC with clinical net benefit in a range of risk thresholds (2% to 5%). Survivors of IPLC with radiotherapy likely had a low risk of metachronous SPLC during the first five years follow-up, especially non-small cell lung cancer.

MNX1-AS1 is a novel biomarker for predicting clinical progression and poor prognosis in lung adenocarcinoma

Motor neuron and pancreas homeobox 1-antisense RNA1 (MNX1-AS1) is a novel long noncoding RNA and has been suggested to be overexpressed in human ovarian cancer and glioma. The role of MNX1-AS1 in lung cancer was still unknown. In our study, we observed levels of MNX1-AS1 expression through analyzing The Cancer Genome Atlas and found MNX1-AS1 expression was highly expressed in lung adenocarcinoma tissues compared with normal lung tissues, but there was no statistical difference between lung squamous cell carcinoma tissues and normal lung tissues. Furthermore, we conducted quantitative real-time polymerase chain reaction, and confirmed that the expression of MNX1-AS1 was definitely higher in lung adenocarcinoma tissue samples, but not in lung squamous cell carcinoma tissue samples. In addition, high MNX1-AS1 expression was found to be associated with the low differentiated degree, advanced clinical stage, big tumor size, lymph node metastasis, and distant metastasis in lung adenocarcinoma patients. High expression of MNX1-AS1 was negatively correlated with overall survival time and served as an independent unfavorable prognostic factor in patients with lung adenocarcinoma. The in vitro functional studies suggested that suppression of MNX1-AS1 inhibited lung adenocarcinoma cell proliferation and migration, and promoted apoptosis. In conclusion, MNX1-AS1 is overexpressed in lung adenocarcinoma, and associated with clinical progression and poor prognosis.