Frederic Deschamps

Background: Electrochemotherapy (ECT) of vertebral metastasis is a new treatment option for metastasis that is not accessible to thermal ablation or radiotherapy. A numerical feasibility study has investigated the transpedicular approach for electrode insertion. We conducted a preclinical study to assess its safety. Methods: Histologic examination of the spinal cord was performed in 12 consecutive pigs treated with ECT at three consecutive levels (T11, T12, and L1) to evaluate any cellular or vascular damage. Pigs of group A (n = 6) had an intraoperative neuromonitoring immediately for 1 h after ECT and then were euthanized. Pain and clinical symptoms were daily evaluated for group B (n = 3) and group C (n = 3) until day-3 and day-30, respectively. Results: At gross pathology, no apoptosis, no vascular/thrombosis or hemorrhagic focus was observed in any pig. Motor-evoked potential responses of the lower limbs were transiently lost in response in 5 of the 6 pigs, but complete recovery always occurred within 30 min. Clinical examination (groups B and C) revealed no symptoms during the follow-up. Pigs were all able to walk normally, without weakness or paralysis of the lower extremities. No urinary/fecal retention or incontinence was observed, nor any sign of pain. Conclusion: Our results confirm that the insertion of electrodes through the pedicles is safe for the ECT of vertebral metastases. Further studies are needed to evaluate the safety profile of ECT of vertebral metastases invading the cortical and epidural fat, which represents a privileged pathway for the electric field between the electrodes. Relevance statement: Electrochemotherapy of vertebral metastases should be performed using a transpedicular approach for the insertion of electrodes, without definitive sequelae at the spinal cord level. Key Points: Electrochemotherapy is a new treatment for vertebral metastases not accessible to radiotherapy, but it could result in spinal cord injury related to electrical trauma. In a swine model, the transpedicular approach has demonstrated no definitive sequelae at intraoperative neuromonitoring and during clinical follow-up. Electrochemotherapy should be performed using a transpedicular approach to avoid spinal cord damage. Graphical

This review aims to analyse the safety and clinical efficacy in terms of pain relief and local tumour control, in patients with metastatic epidural spinal cord compression undergoing electrochemotherapy (ECT). Moreover, a recommendation detailing optimal electrodes insertion is proposed with the intent of improving treatment planning. Clinical studies published between 2015 and 2023 were included since this time window is consistent with recent developments in the field of ECT of spinal metastases. In the whole, 3 articles were included. Results showed that percutaneous image-guided ECT provides effective pain relief with limited procedure-related morbidity, along with local tumour control (complete response 28.5%, 38% partial response, 24% stable disease) at 3-month follow-up in the largest published series so far. In conclusion, ECT should integrate the armamentarium of therapies that are currently being proposed to patients with painful metastatic epidural disease.

With the rapidly evolving field of image-guided tumor ablation, there is an increasing demand and need for tools to optimize treatment success. Known factors affecting the success of (non-)thermal liver ablation procedures are the ability to optimize tumor and surrounding critical structure visualization, ablation applicator targeting, and ablation zone confirmation. A recent study showed superior local tumor progression-free survival and local control outcomes when using transcatheter computed tomography hepatic angiography (CTHA) guidance in percutaneous liver ablation procedures. This pictorial review provides eight clinical cases from three institutions, MD Anderson (Houston, TX, USA), Gustave Roussy (Paris, France), and Amsterdam UMC (Amsterdam, The Netherlands), with the intent to demonstrate the added value of real-time CTHA guided tumor ablation for primary liver tumors and liver-only metastatic disease. The clinical illustrations highlight the ability to improve the detectability of the initial target liver tumor(s) and identify surrounding critical vascular structures, detect ‘vanished’ and/or additional tumors intraprocedurally, differentiate local tumor progression from non-enhancing scar tissue, and promptly detect and respond to iatrogenic hemorrhagic events. Although at the cost of adding a minor but safe intervention, CTHA-guided liver tumor ablation minimizes complications of the actual ablation procedure, reduces the number of repeat ablations, and improves the oncological outcome of patients with liver malignancies. Therefore, we recommend adopting CTHA as a potential quality-improving guiding method within the (inter)national standards of practice.

Purpose: We report a 10-year experience in cancer therapy with concomitant treatment of percutaneous thermal ablation (PTA) and immune checkpoint blockers (ICBs). Material and methods: This retrospective cohort study included all patients at a single tertiary cancer center who had received ICBs at most 90 days before, or 30 days after, PTA. Feasibility and safety were assessed as the primary outcomes. The procedure-related complications and immune-related adverse events (irAEs) were categorized according to the Common Terminology Criteria for Adverse Events v5.0 (CTCAE). Efficacy was evaluated based on overall survival (OS), progression-free survival (PFS), and local progression-free survival (_LPFS) according to the indication, ablation modality, neoplasm histology, and ICB type. Results: Between 2010 and 2021, 78 patients (57% male; median age: 61 years) were included. The PTA modality was predominantly cryoablation (CA) (61%), followed by radiofrequency ablation (RFA) (31%). PTA indications were the treatment of oligo-persistence (29%), oligo-progression (14%), and palliation of symptomatic lesions or prevention of skeletal-related events (SREs) (56%). Most patients received anti-PD1 ICB monotherapy with pembrolizumab (n = 35) or nivolumab (n = 24). The feasibility was excellent, with all combined treatment performed and completed as planned. Ten patients (13%) experienced procedure-related complications (90% grade 1–2), and 34 patients (44%) experienced an irAE (86% grade 1–2). The only factor statistically associated with better OS and PFS was the ablation indication, favoring oligo-persistence (p = 0.02). Tumor response was suggestive of an abscopal effect in four patients (5%). Conclusions: The concomitant treatment of PTA and ICBs within 2–4 weeks is feasible and safe for both palliative and local control indications. Overall, PTA outcomes were found to be similar to standards for patients not on ICB therapy. While a consistently reproducible abscopal effect remains elusive, the safety profile of concomitant therapy provides the framework for continued assessment as ICB therapies evolve.

Background: Patients with metastatic medullary thyroid cancer (MTC) who progressed under tyrosine kinase inhibitors can benefit from alkylating agent such as Dacarbazine or Temozolomide. Patient Findings: We describe two patients with metastatic MTC who developed a hypermutant phenotype after alkylating agent treatment. This phenotype was characterized by a high tumor mutational burden (TMB) and a mutational signature indicative of alkylating agent mutagenesis (Single Base Substitution 11). Both patients received immune checkpoint inhibitors, with partial morphological responses, clinical benefit and PFS of 6 and 9 months respectively. Summary and Conclusions: Based on the described observations, we suggest that a hypermutant phenotype may be induced after alkylating agent treatment for MTC and the sequential use of immunotherapy should be further explored as a treatment option for MTC patients with increased TMB.

To evaluate the technical feasibility and outcomes of thermal ablation following selective intra-arterial lipiodol injection (SIALI) for targeting primary and secondary liver tumors invisible on ultrasound (US) and non-contrast computed tomography (CT). This retrospective study included 18 patients with 20 tumors (67% male, mean age 60.8 ± 12.1 years). The 20 tumors included 15 liver metastases and 5 hepatocellular carcinomas. All patients underwent single-session SIALI and subsequent CT-guided thermal ablation. The primary outcome was a technical success, defined as visualization of the tumor after SIALI and successful thermal ablation. Secondary outcomes were local recurrence rate and procedure-related complications. The median tumor size was 1.5 (1-2.5) cm. In addition, SIALI was performed with a median volume of 3 (1-10) mL of lipiodol resulting in intra-tumoral iodized oil accumulation in 19 tumors and negative imprint with iodized oil accumulation of the surrounding liver parenchyma in 1 tumor. The technical success rate was 100%. No local occurrence was observed at a mean follow-up time of 3 ± 2.5 years. SIALI to tag liver tumors not visible with US and non-contrast CT before percutaneous ablation is highly feasible and has a high success rate for the treatment of both primary and secondary liver tumors.