Electrochemotherapy of Spinal Metastases Using Transpedicular Approach-A Numerical Feasibility Study

Electrochemotherapy in Aggressive Hemangioma of the Spine: A Case Series and Narrative Literature Review

(1) Background: this case series and literature review aims to evaluate the efficacy and safety of electrochemotherapy in the management of aggressive spinal hemangiomas, presenting two distinct cases. (2) Methods: we present two cases of spinal aggressive hemangioma which were refractory to conventional treatments and underwent electrochemotherapy. Case 1 involves a 50-year-old female who presented with an aggressive spinal hemangioma of L1, who previously underwent various treatments including surgery, radio-chemotherapy, and arterial embolization. Case 2 describes a 16-year-old female with a T12 vertebral hemangioma, previously treated with surgery and stabilization, who faced limitations in treatment options due to her young age and the location of the hemangioma. (3) Results: in Case 1, electrochemotherapy with bleomycin was administered following the failure of previous treatments and resulted in the reduction of the lesion size and improvement in clinical symptoms. In Case 2, electrochemotherapy was chosen due to the risks associated with other treatments and was completed without any adverse events. Both cases demonstrated the potential of electrochemotherapy as a viable treatment option for spinal hemangiomas, especially in complex or recurrent cases. (4) Conclusions: electrochemotherapy with bleomycin is a promising treatment for aggressive spinal hemangiomas when conventional therapies are not feasible or have failed. Further research is needed to establish definitive protocols and long-term outcomes of electrochemotherapy in spinal hemangioma management.

Bioactive and electrically conductive GelMA-BG-MWCNT nanocomposite hydrogel bone biomaterials

Natural bone is a complex organic-inorganic composite tissue that possesses endogenous electrically conductive properties in response to mechanical forces. Mimicking these unique properties collectively in a single synthetic biomaterial has so far remained a formidable task. In this study, we report a synthesis strategy that comprised gelatin methacryloyl (GelMA), sol-gel derived tertiary bioactive glass (BG), and uniformly dispersed multiwall carbon nanotubes (MWCNTs) to create nanocomposite hydrogels that mimic the organic-inorganic composition of bone. Using this strategy, biomaterials that are electrically conductive and possess electro-mechanical properties similar to endogenous bone were prepared without affecting their biocompatibility. Nanocomposite hydrogel biomaterials were biodegradable and promoted biomineralization, and supported multipotent mesenchymal progenitor cell (10T1/2) cell interactions and differentiation into an osteogenic lineage. To the best of our knowledge, this work presents the first study to functionally characterize suitable electro-mechanical responses in nanocomposite hydrogels, a key process that occurs in the natural bone to drive its repair and regeneration. Overall, the results demonstrated GelMA-BG-MWCNT nanocomposite hydrogels have the potential to become promising bioactive biomaterials for use in bone repair and regeneration.

Electrochemotherapy in radiotherapy-resistant epidural spinal cord compression in metastatic cancer patients

OBJECTIVE

To report efficacy and safety of percutaneous electrochemotherapy (ECT) in patients with radiotherapy-resistant metastatic epidural spinal cord compression (MESCC).

MATERIAL/ METHODS

This retrospective study analyzed all consecutive patients treated with bleomycin-based ECT between February-2020 and September-2022 in a single tertiary referral cancer center. Changes in pain were evaluated with the Numerical Rating Score (NRS), in neurological deficit with the Neurological Deficit Scale, and changes in epidural spinal cord compression were evaluated with the epidural spinal cord compression scale (ESCCS) using an MRI.

RESULTS

Forty consecutive solid tumour patients with previously radiated MESCC and no effective systemic treatment options were eligible. With a median follow-up of 5.1 months [1-19.1], toxicities were temporary acute radicular pain (25%), prolonged radicular hypoesthesia (10%), and paraplegia (7.5%). At 1 month, pain was significantly improved over baseline (median NRS: 1.0 [0-8] versus 7.0 [1.0-10], P < .001) and neurological benefits were considered as marked (28%), moderate (28%), stable (38%), or worse (8%). Three-month follow-up (21 patients) confirmed improved over baseline (median NRS: 2.0 [0-8] versus 6.0 [1.0-10], P < .001) and neurological benefits were considered as marked (38%), moderate (19%), stable (33.5%), and worse (9.5%). One-month post-treatment MRI (35 patients) demonstrated complete response in 46% of patients by ESCCS, partial response in 31%, stable disease in 23%, and no patients with progressive disease. Three-month post-treatment MRI (21 patients) demonstrated complete response in 28.5%, partial response in 38%, stable disease in 24%, and progressive disease in 9.5%.

CONCLUSIONS

This study provides the first evidence that ECT can rescue radiotherapy-resistant MESCC.

Optimization of Transpedicular Electrode Insertion for Electroporation-Based Treatments of Vertebral Tumors

Electroporation-based treatments such as electrochemotherapy and irreversible electroporation ablation have sparked interest with respect to their use in medicine. Treatment planning involves determining the best possible electrode positions and voltage amplitudes to ensure treatment of the entire clinical target volume (CTV). This process is mainly performed manually or with computationally intensive genetic algorithms. In this study, an algorithm was developed to optimize electrode positions for the electrochemotherapy of vertebral tumors without using computationally intensive methods. The algorithm considers the electric field distribution in the CTV, identifies undertreated areas, and uses this information to iteratively shift the electrodes from their initial positions to cover the entire CTV. The algorithm performs successfully for different spinal segments, tumor sizes, and positions within the vertebra. The average optimization time was 71 s with an average of 4.9 iterations performed. The algorithm significantly reduces the time and expertise required to create a treatment plan for vertebral tumors. This study serves as a proof of concept that electrode positions can be determined (semi-)automatically based on the spatial information of the electric field distribution in the target tissue. The algorithm is currently designed for the electrochemotherapy of vertebral tumors via a transpedicular approach but could be adapted for other anatomic sites in the future.

Electrochemotherapy Is Effective in the Treatment of Bone Metastases

Bone metastases induce pain, risk of fracture, and neural compression, and reduced mobility and quality of life. Electrochemotherapy (ECT) is a minimally invasive local treatment based on a high-voltage electric pulse combined with an anticancer drug. Preclinical and clinical studies have supported the use of ECT in patients with metastatic bone disease, demonstrating that it does not damage the mineral structure of the bone and its regenerative capacity, and that is feasible and efficient for the treatment of bone metastases. Since 2009, 88 patients with bone metastasis have received ECT at the Rizzoli Institute. 2014 saw the start of a registry of patients with bone metastases treated with ECT, whose data are recorded in a shared database. We share the Rizzoli Institute experience of 38 patients treated with ECT for a bone metastasis, excluding patients not included in the registry (before 2014) and those treated with bone fixation. Mean follow-up was 2 months (1–52). Response to treatment using RECIST criteria was 29% objective responses, 59% stable disease, and 16% progressive disease. Using PERCIST, the response was 36% OR, 14% SD, and 50% PD with no significant differences between the two criteria. A significant decrease in pain and better quality of life was observed at FU.

Electrochemotherapy treatment safety under parallel needle deflection

Electrochemotherapy is a selective electrical-based cancer treatment. A thriving treatment depends on the local electric field generated by pairs of electrodes. Electrode damage as deflection can directly affect this treatment pillar, the distribution of the electric field. Mechanical deformations such as tip misshaping and needle deflection are reported with needle electrode reusing in veterinary electrochemotherapy. We performed in vitro and in silico experiments to evaluate potential problems with ESOPE type II electrode deflection and potential treatment pitfalls. We also investigated the extent to which the electric currents of the electroporation model can describe deflection failure by comparing in vitro with the in silico model of potato tuber (Solanum tuberosum). The in silico model was also performed with the tumor electroporation model, which is more conductive than the vegetal model. We do not recommend using deflected electrodes. We have found that a deflection of ± 2 mm is unsafe for treatment. Inward deflection can cause dangerous electrical current levels when treating a tumor and cannot be described with the in silico vegetal model. Outward deflection can cause blind spots in the electric field.

Adjuvant electrochemotherapy after debulking in canine bone osteosarcoma infiltration

Osteosarcoma is a bone cancer considered rare to humans, but common in dogs. Dogs and humans share genetic homology and environmental risk factors. Improving the treatment of osteosarcoma in dogs could also be relevant to improve procedures in humans. Traditional treatments of osteosarcoma involve surgery and chemotherapy. Such treatments are commonly aggressive and not possible for many patients. Electrochemotherapy emerges as a minimally invasive, effective, and safe treatment alternative. Electrochemotherapy combines applications of high-intensity electric fields during short periods with anti-cancer drugs to improve its medicine cytotoxicity. Analyzing the electric field distribution, as well as electric current density, are essential to electrochemotherapy success. This paper brings the first case of a canine osteosarcoma treatment performed with bleomycin and electrochemotherapy. We performed in silico studies with finite element method software to observe the electric field distribution. In silico experiments help to verify possibilities and limitations of treating bone destruction and macro or micro tumor infiltrations around the primary tumor mass. Results show that both needle or plate electrodes are feasible to remove the tumor even with invasion into the bone. Plate electrodes perform well in treating micro infiltrations when associated with conductive gel and direct contact between electrode and bone (without soft tissues). Needle electrodes are effective in treating tumor infiltration on external cortical bone. Multiple applications are needed to cover all cranium layers with sufficient electric field intensity. Electrochemotherapy protocol with needle or plate electrodes does not present sufficient electric current density capable of affecting brain tissue, even in cases of bone destruction.

Percutaneous image guided electrochemotherapy of hepatocellular carcinoma: technological advancement

Background

Electrochemotherapy is an effective treatment of colorectal liver metastases and hepatocellular carcinoma (HCC) during open surgery. The minimally invasive percutaneous approach of electrochemotherapy has already been performed but not on HCC. The aim of this study was to demonstrate the feasibility, safety and effectiveness of electrochemotherapy with percutaneous approach on HCC.

Patient and methods

The patient had undergone the transarterial chemoembolization and microwave ablation of multifocal HCC in segments III, V and VI. In follow-up a new lesion was identified in segment III, and recognized by multidisciplinary team to be suitable for minimally invasive percutaneous electrochemotherapy. The treatment was performed with long needle electrodes inserted by the aid of image guidance.

Results

The insertion of electrodes was feasible, and the treatment proved safe and effective, as demonstrated by control magnetic resonance imaging.

Conclusions

Minimally invasive, image guided percutaneous electrochemotherapy is feasible, safe and effective in treatment of HCC.

Recent Advances in Electrochemotherapy

Electrochemotherapy is gaining recognition as an effective local therapy that uses systemically or intratumorally injected bleomycin or cisplatin with electroporation as a delivery system that brings drugs into the cells to exert their cytotoxic effects. Preclinical work is still ongoing, testing new drugs, seeking the best treatment combination with other treatment modalities, and exploring new sets of pulses for effective tissue electroporation. The applications of electrochemotherapy are being fully exploited in veterinary oncology, where electrochemotherapy, because of its simple execution, has a relatively good cost-benefit ratio and is used in the treatment of cutaneous tumors. In human oncology, electrochemotherapy is fully recognized as a local therapy for cutaneous tumors and metastases. Its effectiveness is being explored in combination with immunomodulatory drugs. However, the development of electrochemotherapy is directed into the treatment of deep-seated tumors with a percutaneous approach. Because of the vast number of reports, this review discusses the articles published in the past 5 years.