Is 18F-FDG-PET/CT an Optimal Imaging Modality for Detecting Immune-Related Adverse Events after Immune-Checkpoint Inhibitor Therapy? Pros and Cons.

Immunotherapy with immune checkpoint inhibitors (ICIs) has revolutionized contemporary oncology, presenting efficacy in various solid tumors and lymphomas. However, ICIs may potentially overstimulate the immune system, leading to immune-related adverse events (irAEs). IrAEs may affect multiple organs, such as the colon, stomach, small intestine, kidneys, skin, lungs, joints, liver, lymph nodes, bone marrow, brain, heart, and endocrine glands (e.g., pancreas, thyroid, or adrenal glands), exhibiting autoimmune inflammation. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is commonly used in oncology for staging and assessment of therapy responses, but it may also serve as a tool for detecting irAEs. This review aims to present various patterns of metabolic activation associated with irAEs due to ICI treatment, identifiable through 18F-FDG PET/CT. It describes the advantages of early detection of irAEs, but also presents the challenges in differentiating them from tumor progression. It also delves into aspects of molecular response assessment within the context of pseudoprogression and hyperprogression, along with typical imaging findings related to these phenomena. Lastly, it summarizes the role of functional PET imaging in oncological immunotherapy, speculating on its future significance and limitations.

Pembrolizumab-combination therapy for NSCLC- effectiveness and predictive factors in real-world practice.

Introduction: Pembrolizumab combined with chemotherapy has become the standard of care for patients with non-small-cell lung cancer (NSCLC) and the expression of programmed death ligand 1 (PD-L1) in <50% of tumour cells (TC). Methods: We evaluated the efficacy of the treatment in real-world practice, paying attention to the predictive factors, with a special focus on low level of PD-L1 expression. This study is a multicenter retrospective analysis of patients with stage IV NSCLC. Results: A group of 339 consecutive patients was analysed, among them 51% patients with low PD-L1 expression. In the overall population, the ORR was 40.6%, median PFS and OS were 13 months (95% CI 11.4-15) and 16.8 months (95% CI 13.3-20.3), respectively. In multivariate analysis for the entire study population, performance status - ECOG 1 vs. 0 (HR 2.2, 95%CI 1.1-4.6; p=0.02), neutrophil to lymphocyte ratio (NLR)>3 (HR 2.3, 95%CI 1.3-4.2; p=0.04), presence of liver (HR 2.0, 95%CI 1-3.7; p=0. 03) and bone metastases (HR 1.3, 95%CI 1-3; p=0.04), weight loss (HR 1.8, 95%CI 1.1-2.8; p=0.01) and sum of measurable lesions diameters >110 mm (HR 1.7, 95%CI 1-2.9, p=0.049) had a negative impact on OS. Conclusions: In the real world, patients can clinically benefit from immunochemotherapy, regardless of the expression of PD-L1 and the histological type. Other clinicopathological factors such as performance status, extent, and location of secondary lesions have prognostic significance.

Concurrent chemoradiotherapy for stage III non-small-cell lung cancer: recent progress and future perspectives (a narrative review).

Concurrent chemoradiotherapy (CHRT) remains the therapeutic standard for locally advanced inoperable non-small-cell lung cancer (NSCLC). The median overall survival (OS) with this approach is in the range of 20-30 months, with five-year survival of approximately 30%. These outcomes have recently been further improved by supplementing CHRT with maintenance durvalumab, a monoclonal anti-PD-L1 agent. The progress in treatment outcomes of locally advanced NSCLC before the era of immunotherapy has been achieved mainly by virtue of developments in diagnostics and radiotherapy techniques. Routine implementation of endoscopic and endobronchial ultrasonography for mediastinal lymph nodes assessment, positron emission tomography/computed tomography and magnetic resonance imaging of the brain allows for more accurate staging of NSCLC and for optimizing treatment strategy. Thorough staging and respiratory motion control allows for higher conformity of radiotherapy and reduction of radiotherapy related toxicity. Dose escalation with prolonged overall treatment time does not improve treatment outcomes of CHRT. In consequence, 60 Gy in 2 Gy fractions or equivalent biological dose remains the standard dose for definitive CHRT in locally advanced NSCLC. However, owing to increased toxicity of CHRT, this option may not be applicable in a proportion of elderly or frail patients. This article summarizes recent developments in curative CHRT for inoperable stage III NSCLC, and presents perspectives for further improvements of this strategy.

Effect of DNA methylation profile on OATP3A1 and OATP4A1 transcript levels in colorectal cancer.

Epidemiological studies indicate that 17ß-estradiol (E2) prevents colorectal cancer (CRC). Organic anion transporting polypeptides (OATPs) are involved in the cellular uptake of various endogenous and exogenous substrates, including hormone conjugates. Because transfer of estrone sulfate (E1-S) can contribute to intra-tissue conversion of estrone to the biologically active form -E2, it is evident that the expression patterns of OATPs may be relevant to the analysis of CRC incidence and therapy. We therefore evaluated DNA methylation and transcript levels of two members of the OATP family, OATP3A1 and OATP4A1, that may be involved in E1-S transport in colorectal cancer patients. We detected a significant reduction in OATP3A1 and a significant increase in OATP4A1 mRNA levels in cancerous tissue, compared with histopathologically unchanged tissue (n=103). Moreover, we observed DNA hypermethylation in the OATP3A1 promoter region in a small subset of CRC patients and in HCT116 and Caco-2 colorectal cancer cell lines. We also observed increased OATP3A1 transcript following treatment with 5-aza-2-deoxycytidine and sodium butyrate. The OATP4A1 promoter region was hypomethylated in analyzed tissues and CRC cell lines and was not affected by these treatments. Our results suggest a potential mechanism for OATP3A1 downregulation that involves DNA methylation during colorectal carcinogenesis.