Neoadjuvant SBRT combined with immunotherapy in NSCLC: from mechanisms to therapy

Novel therapeutic approaches for non-small cell lung cancer: an updated view

Non-small cell lung cancer (NSCLC) continues to be one of the leading causes of cancer-related mortality globally. Most patients who undergo surgical procedures may encounter distant metastasis or local recurrence, necessitating supplementary treatments such as radiation therapy, chemotherapy, or targeted therapy as adjuvant alternatives. Recent advancements in molecular biology and immunotherapy have paved the way for innovative therapeutic approaches that target specific genetic mutations and promote the immune response against tumour cells. This review explores emerging therapies, including targeted therapies such as tyrosine kinase inhibitors (TKIs) for actionable mutations (e.g., EGFR, ALK, ROS1), as well as the role of immune checkpoint inhibitors (ICIs) that employ the body's immune system to combat cancer. Additionally, we discuss the potential of exosome therapies, as well as promising nanotherapeutic options for the treatment of NSCLC. This study attempts to provide a thorough overview of the changing landscape of NSCLC treatment and its implications for enhancing patient outcomes by presenting these innovative techniques.

Deciphering T-cell exhaustion in the tumor microenvironment: paving the way for innovative solid tumor therapies

In solid tumors, the tumor microenvironment (TME) is a complex mix of tumor, immune, stromal cells, fibroblasts, and the extracellular matrix. Cytotoxic T lymphocytes (CTLs) constitute a fraction of immune cells that may infiltrate into the TME. The primary function of these T-cells is to detect and eliminate tumor cells. However, due to the immunosuppressive factors present in the TME primarily mediated by Myeloid-Derived Suppressor Cells (MDSCs), Tumor associated macrophages (TAMs), Cancer Associated Fibroblasts (CAFs) as well as the tumor cells themselves, T-cells fail to differentiate into effector cells or become dysfunctional and are unable to eliminate the tumor. In addition, chronic antigen stimulation within the TME also leads to a phenomenon, first identified in chronic lymphocytic choriomeningitis virus (LCMV) infection in mice, where the T-cells become exhausted and lose their effector functions. Exhausted T-cells (Tex) are characterized by the presence of remarkably conserved inhibitory receptors, transcription and signaling factors and the downregulation of key effector molecules. Tex cells have been identified in various malignancies, including melanoma, colorectal and hepatocellular cancers. Recent studies have indicated novel strategies to reverse T-cell exhaustion. These include checkpoint inhibitor blockade targeting programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin-domain containing-3 (Tim-3), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), or combinations of different immune checkpoint therapies (ICTs) or combination of ICTs with cytokine co-stimulation. In this review, we discuss aspects of T-cell dysfunction within the TME with a focus on T-cell exhaustion. We believe that gaining insight into the mechanisms of T-cell exhaustion within the TME of human solid tumors will pave the way for developing therapeutic strategies to target and potentially re-invigorate exhausted T-cells in cancer.

Efficacy and safety of combining radiotherapy with immune checkpoint inhibitors in patients with advanced non-small cell lung cancer: a real-world study

BACKGROUND

The significance of local radiotherapy (RT) in advanced non-small-cell lung cancer (NSCLC) is well documented. However, the advent of immunotherapy has raised questions regarding the synergistic survival benefits or potential adverse effects.

OBJECTIVE

This study aimed to explore whether a combination of RT and systematic immune checkpoint inhibitors (ICIs) can improve the survival outcomes for NSCLC patients.

METHODS

Based on collected data patients who received RT were defined as the RT group, and those who had not for any site were defined as the non-RT group. Propensity score matching (PSM) was employed to mitigate bias. The primary endpoint was progression-free survival (PFS), with secondary endpoints including overall survival (OS) and treatment-related adverse events (AEs).

RESULTS

Out of 709 patients (235 in RT group and 474 in non-RT group) were included, with 213 patients per group. The median PFS of the RT group was better than that of the non-RT group (13.8 months versus 9.5 months; p < 0.0001), although no superiority in median overall survival (OS) of the RT group was observed (p = 0.715). However, among the cohort of patients with ≤3 metastases, the median OS of the RT group improved significantly (HR = 0.60, [95% CI 0.44-0.83]; p = 0.004). Treatment-related AEs occurred in 94.5% of RT group patients and in 94.9% of non-RT group patients (p = 0.792), which indicated no observable increase in AEs from RT.

CONCLUSIONS

These results demonstrate the tolerability of RT when administered along with immunotherapy, suggesting its potential to positively impact the survival outcomes of NSCLC patients.

Neoadjuvant immunotherapy strategies for resectable non-small cell lung cancer (NSCLC): Current evidence among special populations and future perspectives

About one third of patients with Non-Small Cell Lung Cancer (NSCLC) presents at diagnosis with localized or locally advanced disease amenable to curative surgical resection. Surgical operability refers to stage I to IIIA and selected stage IIIB NSCLC. One of the main challenges in the management of early-stage resectable NSCLC is the optimization of available therapeutic strategies to prevent local and distant disease relapse, thus improving survival outcomes. There is evidence supporting the clinical use of both adjuvant and neoadjuvant immunotherapy-based strategies for resected/resectable, stage IB-IIIA NSCLC. Available data from randomized phase III trials have led to the incorporation of several immune checkpoint blockers (ICBs) into the international guidelines for early-stage NSCLC. Preclinical rationale of targeting specific subsets of T-cells by acting early on immune checkpoint receptors (e.g., PD-(L)1 and CTLA-4) is strong. Recent evidence is in favor of the neoadjuvant approach alone or as a part of perioperative strategy, demonstrating survival benefit. Combining neoadjuvant chemotherapy and immunotherapy before surgery results in both pathologic complete response (pCR) and major pathologic response (MPR) improvement, and survival outcomes, with no major safety issues. In this review, we summarize the rationale behind neoadjuvant/perioperative immunotherapy strategies and, due to the clinical relevance of immunotherapy in resectable NSCLC, we provide current evidence of this cutting-edge approach among special populations including older adults, women, and oncogene addicted NSCLC. To conclude, we present future perspectives in the use of immunotherapy for operable NSCLC with a special focus on novel investigational combinations underway.

Neoadjuvant Radiochemotherapy Alters the Immune and Metabolic Microenvironment in Oral Cancer-Analyses of CD68, CD163, TGF-β1, GLUT-1 and HIF-1α Expressions

BACKGROUND

The first-line treatment of oral squamous cell carcinoma (OSCC) involves surgical tumor resection, followed by adjuvant radio(chemo)therapy (R(C)T) in advanced cases. Neoadjuvant radio- and/or chemotherapy has failed to show improved survival in OSCC. Recently, neoadjuvant immunotherapy has shown promising therapeutic efficacy in phase 2 trials. In this context, the addition of radio- and chemotherapy is being reconsidered. Therefore, a better understanding of the tumor-biologic effects of neoadjuvant RCT would be beneficial. The current study was conducted on a retrospective cohort of patients who received neoadjuvant RCT for the treatment of oral cancer. The aim of the study was to evaluate the influence of neoadjuvant RCT on the immunological tumor microenvironment (TME) and hypoxic and glucose metabolisms.

METHODS

A cohort of 45 OSSC tissue samples from patients were analyzed before and after RCT (total 50.4 Gy; 1.8 Gy 5× weekly; Cisplatin + 5-Fluorouracil). Immunohistochemistry for CD68, CD163, TGF-β, GLUT-1 and HIF-1α was performed using tissue microarrays and automated cell counting. Differences in expression before and after RCT and associations with histomorphological parameters (T-status, N-status) were assessed using the Mann-Whitney U test.

RESULTS

Tumor resection specimens after neoadjuvant RCT showed a significant decrease in CD68 infiltration and a significant increase in CD163 cell density. The CD68/CD163 ratio was significantly lower after RCT, indicating a shift toward M2 polarization. The GLUT-1 and HIF-1α expressions were significantly lower after RCT. Larger tumors (T3/T4) showed a lower GLUT-1 expression. Other biomarkers were not associated with the T- and N-status.

CONCLUSIONS

Neoadjuvant RCT with 50.4 Gy induced a shift toward the M2 polarization of macrophages in the TME. This change in immune composition is not favorable and may be prognostically negative and counteract immunotherapeutic approaches. In addition, the decreased expressions in GLUT-1 and HIF-1α indicate reductions in the glucose metabolism and hypoxic energy metabolism in response to "high dose" neoadjuvant RCT, which may be therapeutically desirable.

Differences between Survival Rates and Patterns of Failure of Patients with Lung Adenocarcinoma and Squamous Cell Carcinoma Who Received Single-Fraction Stereotactic Body Radiotherapy

We investigated the survival and patterns of failure in adenocarcinoma (ADC) and squamous cell carcinoma (SCC) in early stage non-small cell lung cancer (NSCLC) treated with single-fraction stereotactic body radiation therapy (SF-SBRT) of 27-34 Gray. A single-institution retrospective review of patients with biopsy-proven early stage ADC or SCC undergoing definitive SF-SBRT between September 2008 and February 2023 was performed. The primary outcomes were overall survival (OS) and disease-free survival (DFS). The secondary outcomes included local failure (LF), nodal failure (NF), and distant failure (DF). Of 292 eligible patients 174 had adenocarcinoma and 118 had squamous cell carcinoma. There was no significant change in any outcome except distant failure. Patients with ADC were significantly more likely to experience distant failure than patients with SCC (p = 0.0081). In conclusion, while SF-SBRT produced similar LF, NF, DFS, and OS, the higher rate of distant failure in ADC patients suggests that ongoing trials of SBRT and systemic therapy combinations should report their outcomes by histology.

Immunotherapy for the elderly. Maybe the best option for lung cancer?

Lung cancer is usually diagnosed at advanced stage and systematic therapy is administered. New current diagnostic techniques such as the convex-endobronchial ultrasound, radial endobronchial ultrasound, cone beam ct, electromagnetic navigation and robotic bronchoscopy provide us with a high diagnostic yield. These techniques are minimal invasive and patients with comorbidities such as chronic obstructive pulmonary disease and heart failure can be diagnosed with minimal adverse effects. All these techniques provide sufficient sample for molecular investigation. Since immunotherapy was first administered, we have more and more information regarding the appropriate patient target group. Several published studies divided patients as elderly ≥75 and non-elderly ≤74 and investigated the adverse effects of different drugs and survival. In our current commentary we present information on patients receiving immunotherapy versus chemoimmunotherapy in two groups of elderly and non-elderly. Elderly patients can receive both combinations without differences between the two groups, however; more studies are needed to clarify certain aspects.