CT-guided percutaneous chemoablation using an ethanol-ethiodol-doxorubicin emulsion for the treatment of metastatic lymph node carcinoma: a comparative study

Chemo-immunoablation of solid tumors: A new concept in tumor ablation

Chemical ablation was designed to inject chemical agents directly into solid tumors to kill cells and is currently only used clinically for the palliative treatment of tumors. The application and combination of different drugs, from anhydrous ethanol, and glacial acetic acid to epi-amycin, have been clinically tested for a long time. The effectiveness is unsatisfactory due to chemical agents' poor diffusion and concentration. Immunotherapy is considered a prospective oncologic therapeutic. Still, the clinical applications were limited by the low response rate of patients to immune drugs and the immune-related adverse effects caused by high doses. The advent of intratumoral immunotherapy has well addressed these issues. However, the efficacy of intratumoral immunotherapy alone is uncertain, as suggested by the results of preclinical and clinical studies. In this study, we will focus on the research of immunosuppressive tumor microenvironment with chemoablation and intratumoral immunotherapy, the synergistic effect between chemotherapeutic drugs and immunotherapy. We propose a new concept of intratumoral chemo-immunoablation. The concept opens a new perspective for tumor treatment from direct killing of tumor cells while, enhancing systemic anti-tumor immune response, and significantly reducing adverse effects of drugs.

Study of epirubicin sustained-release chemoablation in tumor suppression and tumor microenvironment remodeling

Introduction

Although intratumoral chemoablation can obtain an impressive therapeutic effect, there is still incomplete ablation and tumor recurrence in some patients. This could be due to the short retention time of the drug in the tumor, the limited distribution of intratumoral drugs, and, beyond that, the immunotolerance caused by the tumor microenvironment (TME). There is still an urgent need to find an optimal drug sustained-release carrier and figure out the impact of regional injection to TME.

Methods

In this study, we supposed to use polyethylene glycol (PEG) hydrogel as a drug carrier to improve the retention time of the drug to extend the exposure of tumor cells and investigate the feasibility of combination local Epirubicin injection with anti-PD-L1.

Results

The results revealed obvious tumor suppression based on the tumor volume and the inhibition time of tumor growth in the A549 lung cancer mouse model after local injection. Furthermore, the enhanced antitumor effects of the combination of systematic anti- programmed death ligand 1 (PD-L1) therapy with local chemoablation (EPI-GEL/PD-L1) for abscopal tumor reduction in the 4T1 breast model were also observed. Flow cytometry analysis of the tumor and blood samples showed significant variations in the proportions of PD-L1⁺ and CD3⁺CD8⁺PD-1⁺ cells before and after anti-PD-L1 therapy. On day 4 after local injection of the EPI gel, the expression of PD-L1 in abscopal tumors was upregulated, while the expression of PD-L1 in bilateral tumors in mice was significantly reduced after anti-PD-L1 treatment. The proportion of CD3⁺CD8⁺PD-1⁺ cells in the tumor and circulating blood in the EPI-GEL/PD-L1 group was decreased compared with that in the EPI-GEL (single injection of epirubicin) group.

Discussion

The combination of local injection of the chemoablation agent with anti-PD-L1 monoclonal antibody (mAb) therapy may strengthen the antitumor activity, and the use of PEG hydrogel as the drug carrier can extend the retention time of the chemoablation agent around the tumor, maintaining a long-term tumor-killing activity.

Transcatheter Arterial Chemoembolization Combined with Simultaneous Computed Tomography-guided Radiofrequency Ablation for Large Hepatocellular Carcinomas

BACKGROUND

Currently, the treatment of large hepatocellular carcinoma (HCC) is still a challenging problem. Transcatheter arterial chemoembolization (TACE) is the main treatment for intermediate end-stage HCC, while it is only a palliative and not a curative treatment due to the existence of residual tumors, and radiofrequency ablation (RFA) has limitations in complete ablation of large HCC. We hypothesized that TACE combined with simultaneous RFA (herein referred to as TACE + RFA) could improve the efficacy and survival of large HCC. This study aimed to investigate the feasibility, efficacy, and safety of TACE + RFA on single large HCC.

METHODS

A total of 66 patients with single large HCC (≥5 cm in diameter) were recruited between February 2010 and June 2016. TACE was first performed and computed tomography was performed immediately after TACE, and the lesions with poor lipiodol deposition were subjected to simultaneous RFA. The success rate, technique-related complications, liver and kidney functions, serum alpha-fetoprotein (AFP) levels, progression-free survival (PFS), median survival time (MST), focal control rate, and long-term survival rate were evaluated.

RESULTS

TACE + RFA were performed smoothly in all the patients with the success rate of 100%. Intra- and post-operative severe complications were not observed. There were no marked differences in mean alanine transaminase or aspartate transaminase before TACE + RFA compared with 7 days after TACE + RFA (all P > 0.05). In 57 AFP-positive patients, the levels of serum AFP were reduced by 100.0%, 100.0%, and 94.7% at 1, 3, and 6 months after TACE + RFA, respectively; the tumor control rates (complete remission + partial remission) were 100.0% (66/66), 92.4% (61/66), 87.9% (58/66), and 70.1% (39/55) at 1, 3, 6, and 12 months after TACE + RFA, respectively. Patients were followed up for 7-82 months after TACE + RFA. The MST was 18.3 months, PFS was 14.2 ± 6.2 months, and the 1-, 3-, and 5-year survival rates were 93.2% (55/59), 42.5% (17/40), and 27.2% (9/33), respectively.

CONCLUSION

TACE + RFA is safe, feasible, and effective in enhancing the focal control rate and survival rate of patients with large HCC.

Percutaneous Tumor Ablation: Cryoablation Facilitates Targeting of Free Epirubicin-Ethanol-Ioversol Solution Interstitially Coinjected in a Rabbit VX2 Tumor Model

This acute study was aimed at exploring the ability of a cryoablative lesion to drive the distribution of a concomitant in situ injection of a free epirubicin-ethanol-ethiodol-methylene blue mixture. We report the feasibility and safety of this new percutaneous computed tomography-guided combinatorial ablative procedure on VX2 tumors. Eight New Zealand white rabbits bearing 16 tumors on both side of the back muscle were randomly selected and treated on the same day with the following procedures: (1) 8 concomitant cryoablation and interstitial chemotherapy and (2) 8 intratumor marginal chemotherapy. For the latter, an injection needle was positioned at the inner distal margin of a first selected tumor side, where the chemotherapy was delivered during 5 serial sequences. For the concomitant therapy, a single cryoneedle maintained the ice front at the tumor margin, where a needle delivered the drug dose during 5 freeze-injection-thaw sequences. Enhanced computed tomography scans on days 3, 7, and 10 assessed the tumor contours and the tracer localization. Two rabbits were killed on days 0, 3, 7, and 10 for gross and histopathological analyses. During the concomitant therapy, ioversol was distributed at the tumor and iceball margins along with the methylene blue. Enhanced computed tomography on days 3, 7, and 10 showed a focal enlarging defect of the tumor marginal enhancing rim. The rim coincided with focal necrosis at histopathology. During the intratumor chemotherapy procedure, computed tomography showed that the tracers distributed mostly over the tumor mass. No marginal necrosis was detected at histopathology. On day 10, the tumor size for the intratumor chemotherapy group was twice that of the concomitant therapy group. No adverse events were observed. In this VX2 tumor model, our image-guided concomitant therapy is feasible and may enhance the effectiveness of a free epirubicin tracer mixture at the tumor margin.