Role of Adjuvant Radiotherapy in Non-Small Cell Lung Cancer-A Review

The Biological Role of Macrophage in Lung and Its Implications in Lung Cancer Immunotherapy

The lungs are the largest surface of the body and the most important organ in the respiratory system, which are constantly exposed to the external environment. Tissue Resident Macrophages in lung constitutes the important defense against external pathogens. Macrophages connects the innate and adaptive immune system, and also plays important roles in carcinogenesis and cancer immunotherapy. Lung cancer is the leading cause of cancer-related death worldwide, with an overall five-year survival rate of only 21%. Macrophages that infiltrate or aggregate in lung tumor microenvironment are defined as tumor-associated macrophages (TAMs). TAMs are the main components of immune cells in the lung tumor microenvironment. The differentiation and maturation process of TAMs can be roughly divided into two different types: classical activation pathway produces M1 tumor-associated macrophages, and bypass activation pathway produces M2 tumor-associated macrophages. Studies have found that TAMs are related to tumor invasion, metastasis, and treatment resistance, and show potential as a new target for tumor immunotherapy. Therefore, the biological function of macrophages in lung and the role of TAMs in the occurrence, development, and treatment of lung cancer are discussed in this paper.

A Single-Center Experience in Combined Oncological-Surgical Treatment for Resectable Locally Advanced Non-Small Cell Lung Cancer (NSCLC)

Non-small cell lung cancer (NSCLC) is the most common pulmonary malignancy, frequently diagnosed at an advanced stage (III/IV). Patients in the Locally Advanced Stage Subgroup (IIIA) are relatively few, yet compose heterogenic phenotypes, posing a diagnostic and treating challenge, leading to a lack of clinical guidelines regarding the optimal standard of care. Several approaches exist, with a general agreement that a combined oncological and surgical modality approach is required. In this current retrospective descriptive study, patients with operable stage IIIA NSCLC who underwent surgery between 2013 and 2020 were evaluated on several aspects, including the initial diagnosis, neoadjuvant regimens, outcomes of surgical intervention, and overall survival at 2 years and 5 years following treatment. A total of 35 patients had neoadjuvant oncological treatment (mostly chemoradiation therapy) prior to surgery, out of which 28 patients were diagnosed with stage IIIA NSCLC. In post-operative assessment of pathological staging, downstaging was reported in 19 patients, of which 25% of cases were defined as a complete pathological response. The 2-year overall survival rate was 65% and the 5-year overall survival rate was 62%. The main pattern of disease recurrence was distant metastasis.

Impact of travel distance on receipt of indicated adjuvant therapy in resected non-small cell lung cancer

OBJECTIVE

We have previously demonstrated the negative impact of travel distance on adherence to surveillance imaging guidelines for resected non-small cell lung cancer (NSCLC). The influence of patient residential location on adherence to recommended postoperative treatment plans remains unclear. We sought to characterize the impact of travel distance on receipt of indicated adjuvant therapy in resected NSCLC.

METHODS

We performed a single-institution, retrospective review of patients with stage II-III NSCLC who underwent upfront pulmonary resection, 2012-2016. Clinicopathologic and operative/perioperative details of treatment were collected. Travel distance was measured from patients' homes to the operative hospital. Our primary outcome was receipt of adjuvant systemic or radiotherapy. Travel distance was stratified as <100 or >100 miles. Multivariable logistic regression was performed.

RESULTS

In total, 391 patients met inclusion criteria, with mean age of 65.9 years and fairly even sex distribution (182 women, 49.2%). Most patients were Non-Hispanic White (n = 309, 83.5%), and most frequent clinical stage was II (n = 254, 64.9%). Indicated adjuvant therapy was received by 266 (71.9%), and median distance traveled was 209 miles (interquartile range, 50.7-617). Multivariate analysis revealed that longer travel distance was inversely associated with receipt of indicated adjuvant therapy (odds ratio, 0.13; 95% confidence interval, 0.06-0.26; P < .001). In addition, Black patients were less likely to receive appropriate treatment (odds ratio, 0.05; 95% confidence interval, 0.02-0.15; P < .001).

CONCLUSIONS

Travel distance >100 miles negatively impacts the likelihood of receiving indicated adjuvant therapy in NSCLC. Indications for systemic therapy in earlier staged disease are rapidly expanding, and these findings bear heightened relevance as we aim to provide equitable access to all patients.

NSCLC: from tumorigenesis, immune checkpoint misuse to current and future targeted therapy

Non-small cell lung cancer (NSCLC) is largely promoted by a multistep tumorigenesis process involving various genetic and epigenetic alterations, which essentially contribute to the high incidence of mortality among patients with NSCLC. Clinical observations revealed that NSCLC also co-opts a multifaceted immune checkpoint dysregulation as an important driving factor in NSCLC progression and development. For example, a deregulated PI3K/AKT/mTOR pathway has been noticed in 50-70% of NSCLC cases, primarily modulated by mutations in key oncogenes such as ALK, EGFR, KRAS, and others. Additionally, genetic association studies containing patient-specific factors and local reimbursement criteria expose/reveal mutations in EGFR/ALK/ROS/BRAF/KRAS/PD-L1 proteins to determine the suitability of available immunotherapy or tyrosine kinase inhibitor therapy. Thus, the expression of such checkpoints on tumors and immune cells is pivotal in understanding the therapeutic efficacy and has been extensively studied for NSCLC treatments. Therefore, this review summarizes current knowledge in NSCLC tumorigenesis, focusing on its genetic and epigenetic intricacies, immune checkpoint dysregulation, and the evolving landscape of targeted therapies. In the context of current and future therapies, we emphasize the significance of antibodies targeting PD-1/PD-L1 and CTLA-4 interactions as the primary therapeutic strategy for immune system reactivation in NSCLC. Other approaches involving the promising potential of nanobodies, probodies, affibodies, and DARPINs targeting immune checkpoints are also described; these are under active research or clinical trials to mediate immune regulation and reduce cancer progression. This comprehensive review underscores the multifaceted nature, current state and future directions of NSCLC research and treatment.

Is there role of adjuvant radiotherapy after complete resection of locally advanced nonsmall cell lung cancer?

PURPOSE OF REVIEW

This review aims to provide a timely and relevant overview of the role of postoperative radiotherapy (PORT) in completely resected stage IIIA-N2 nonsmall cell lung cancer (NSCLC). Given the controversy surrounding the use of PORT and the emergence of advanced radiation techniques and therapies, this review provides valuable insight into current and potential treatment strategies.

RECENT FINDINGS

The Lung ART and PORT-C trials have provided valuable insights into the efficacy of PORT in stage IIIA-N2 NSCLC. While the results have been mixed, studies have shown that advanced radiation techniques, such as intensity-modulated radiotherapy (IMRT) and proton therapy, can reduce cardiopulmonary toxicities associated with PORT. Molecular targeted therapies and immunotherapies have also shown potential in improving NSCLC treatment outcomes.

SUMMARY

The role of radiotherapy becomes smaller and smaller in new era. However, it is too early to abolish radiotherapy for all the patients after complete resection of locally advanced NSCLC. Nowadays, it is recommended to adopt individualized treatment approaches guided by multidisciplinary team consultations. The integration of IMRT, proton therapy, and emerging therapies offers the potential to enhance treatment efficacy while minimizing toxicity. Further research is needed to optimize the use of PORT and explore the method to identify the patients who can really benefit from PORT.

Update on Adjuvant Treatment in Resectable Non-Small Cell Lung Cancer and Potential Biomarkers Predicting Postoperative Relapse

A significant proportion of patients with non-small cell lung cancer (NSCLC) is diagnosed in the early and resectable stage. Despite the use of platinum-based adjuvant chemotherapy, there was only a marginal increase in overall survival and a 15% decrease in relapse. With the advents of immunotherapy and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), the landscape of adjuvant treatment in completely resectable NSCLC is changing. Postoperative radiotherapy can be beneficial to patients who underwent surgical resection in certain clinical settings. In addition, new biomarkers that predict efficacy of EGFR TKI and immunotherapy as adjuvant treatment are also necessary. In this review, recent updates in adjuvant treatment in resectable NSCLC were briefly explained.