Intravascular Treatment Techniques for Locoregional Therapies of Lung Tumors

BACKGROUND

Lung cancer incidence has greatly increased over the past century. Moreover, the lung is the most common site of metastatic involvement. Despite improvements in the diagnosis and treatment of lung malignancies, patient prognosis is still unsatisfactory. Locoregional chemotherapeutic techniques for the treatment of lung malignancies are the current focus of research. The aim of this review article is to present different locoregional intravascular techniques and their treatment principles and to assess the pros and cons of each of them as a palliative and neoadjuvant treatment method in the treatment of lung malignancy.

METHOD

The different methods for the treatment of malignant lung lesions such as isolated lung perfusion (ILP), selective pulmonary artery perfusion (SPAP), transpulmonary chemoembolization (TPCE), bronchial artery infusion (BAI), bronchioarterial chemoembolization (BACE), and intraarteriel chemoperfusion (IACP) are evaluated comparatively.

RESULTS

Locoregional intravascular chemotherapy procedures are proving to be promising treatment options in the management of malignant lung tumors. In order to achieve optimal results, the locoregional technique should be used to achieve the highest possible uptake of the chemotherapeutic agent into the target tissue with rapid systemic clearance.

CONCLUSION

Among the various treatment options for lung malignancies, TPCE is the best evaluated treatment concept. However, further studies are necessary to define the optimal treatment concept with the best clinical outcomes.

KEY POINTS

· There are various intravascular chemotherapy methods for the treatment of lung malignancies.. · Transpulmonary chemoembolization (TPCE) is currently the most extensively evaluated treatment method for lung malignancies.. · Thermoablation after neoadjuvant chemoperfusion is a promising therapy for treating lung malignancies..

CITATION FORMAT

· Vogl TJ, Mekkawy A, Thabet DB. Intravascular Treatment Techniques for Locoregional Therapies of Lung Tumors. Fortschr Röntgenstr 2023; 195: 579 - 585.

Enhancement of treatment efficacy of hepatic tumours using Trans-arterial-chemoembolization

This review article examines the basic principle underlying trans-arterial chemoembolization (TACE) used for treating unrespectable liver cancer with discussion on the barriers that are present for efficient drug delivery with suggestions on methods that may be used to overcome these barriers and hence enhance the efficacy of the technique. Current drugs used with TACE along with inhibitors of neovascularisation are briefly discussed. It also compares the conventional method of chemoembolization with TACE and rationalizes why there is not much of a difference between the two methods on treatment efficacy. Further it also suggests alternative methods of drug delivery that may be used instead of TACE. Additionally, it discusses the disadvantages on using non degradable microspheres with recommendations for degradable microspheres within 24 hours to overcome rebound neovascularisation owing to hypoxia. Finally, the review examines some of the biomarkers that are used to assess treatment efficacy with indication that non-invasive and sensitive biomarkers should be identified for routine screening and early detection. The review concludes that, if the current barriers present in TACE can be overcome along with the use of degradable microspheres and efficient biomarkers for monitoring efficacy, then a more robust treatment would emerge that may even serve as a cure.

Distinguishing human peripheral blood CD16+ myeloid cells based on phenotypic characteristics

Myeloid lineage cells present in human peripheral blood include dendritic cells (DC) and monocytes. The DC are identified phenotypically as HLA-DR⁺ cells that lack major cell surface lineage markers for T cells (CD3), B cells (CD19, CD20), NK cells (CD56), red blood cells (CD235a), hematopoietic stem cells (CD34), and Mo that express CD14. Both DC and Mo can be phenotypically divided into subsets. DC are divided into plasmacytoid DC, which are CD11c^- , CD304⁺ , CD85g⁺ , and myeloid DC that are CD11c⁺ . The CD11c⁺ DC are readily classified as CD1c⁺ DC and CD141⁺ DC. Monocytes are broadly divided into the CD14⁺ CD16^- (classical) and CD14^dim CD16⁺ subsets (nonclassical). A population of myeloid-derived cells that have DC characteristics, that is, HLA-DR⁺ and lacking lineage markers including CD14, but express CD16 are generally clustered with CD14^dim CD16⁺ monocytes. We used high-dimensional clustering analyses of fluorescence and mass cytometry data, to delineate CD14⁺ monocytes, CD14^dim CD16⁺ monocytes (CD16⁺ Mo), and CD14^- CD16⁺ DC (CD16⁺ DC). We sought to identify the functional and kinetic relationship of CD16⁺ DC to CD16⁺ Mo. We demonstrate that differentiation of CD16⁺ DC and CD16⁺ Mo during activation with IFNγ in vitro and as a result of an allo-hematopoietic cell transplant (HCT) in vivo resulted in distinct populations. Recovery of blood CD16⁺ DC in both auto- and allo-(HCT) patients after myeloablative conditioning showed similar reconstitution and activation kinetics to CD16⁺ Mo. Finally, we show that expression of the cell surface markers CD300c, CCR5, and CLEC5a can distinguish the cell populations phenotypically paving the way for functional differentiation as new reagents become available.

Physical and chemical characteristics of mucin secreted by pseudomyxoma peritonei (PMP)

Background: Pseudomyxoma peritonei (PMP) is a rare disease with excess intraperitoneal mucin secretion. Treatment involves laparotomy, cytoreduction and chemotherapy that is very invasive with patients often acquiring numerous compromises. Hence a mucolytic comprising of bromelain and N-acetyl cystein has been developed to solubilise mucin in situ for removal by catherization. Owing to differences in mucin appearance and hardness, dissolution varies. Therefore the current study investigates the inter-mucin physical and chemical characteristics, in order to reformulate an effective mucolytic for all mucin. Method: PMP mucin, from the three categories (soft, semi hard and hard mucin) was solubilised and then various physical characteristics such as turbidity, density, kinematic viscosity were measured. The water content and the density of solid mucin were also determined. This was followed by the determination of sialic acid, glucose, lipid, Thiol (S-S and S-H) content of the samples. Lastly, the distribution of MUC2, MUC5B and MUC5AC was determined using western blot technique. Results: Both turbidity and kinematic viscosity and sialic acid content increased linearly as the hardness of mucin increased. However, density, hydration, protein, glucose, lipid and sulfhydryl and disulphide content decreased linearly as hardness of mucin increased. The distribution ratio of mucins (MUC2:MUC5B:MUC5AC) in soft mucin is 2.25:1.5:1.0, semi hard mucin is 1:1:1 and hard mucin is 3:2:1. Conclusion: The difference in texture and hardness of mucin may be due to cellular content, hydration, glucose, protein, lipids, thiol and MUC distribution. Soft mucin is solely made of glycoprotein whilst the others contained cellular materials.