Electrochemotherapy of skin metastases from breast cancer: a systematic review

Molecular alterations and prognosis of breast cancer with cutaneous metastasis

PURPOSE

Cutaneous metastasis (CM) accounts for 5-30% of patients with breast cancer (BC) and presents unfavorable response to treatment and poor prognosis. A better understanding of the molecular alterations involved in metastasis is essential, which would help identify diagnostic and efficacy biomarkers for CM.

MATERIALS

We retrospectively reviewed a total of 13 patients with histological or cytological diagnosis of breast cancer and CM. Clinical information was extracted from the medical records. The mutational landscape of matched primary tumors with their lymph nodes or CM tissues were analyzed using next-generation sequencing (NGS) of 425 cancer-relevant genes. All tissues were also analyzed by immunohistochemistry (IHC). The association of prognosis with various clinical and molecular factors was also evaluated.

RESULTS

More than half of the patients were Ki67 low (< 50%, 53.7%). Most patients (12, 92.3%) had other metastasis sites other than skin. The median time from diagnosis to the presentation of CM (T1) was 15 months (range: 0-94 months) and the median time from CM to death (T2) was 13 months (range 1-78). The most frequently altered genes across the three types of tissues were TP53 (69.6%, 16/23), PIK3CA (34.8%, 8/23), and MYC (26.1%). The number of alterations in CM tends to be higher than in primary tumors (median 8 vs. 6, P = 0.077). Copy number loss in STK11, copy number gain in FGFR4, TERT, AR, FLT4 and VEGFA and mutations in ATRX, SRC, AMER1 and RAD51C were significantly enriched in CM (all P < 0.05). Ki67 high group (> 50%) showed significantly shorter T1 than the Ki67 low group (≤ 50%) (median 12.5 vs. 50.0 months, P = 0.036). TP53, PIK3CA mutations, and TERT amplification group were associated with inferior T2 (median 11 vs. 36 months, P = 0.065; 8 vs. 36 months, P = 0.013, 7 vs. 36 months, P = 0.003, respectively). All p values were not adjusted.

CONCLUSION

We compared the genomic features of primary breast cancer tissues with their corresponding CM tissues and discussed potential genes and pathways that may contribute to the skin metastasis of advanced breast cancers patients. TP53, PIK3CA mutant, and TERT amplification may serve as biomarkers for poor prognosis for CM patients.

Identification of PIMREG as a novel prognostic signature in breast cancer via integrated bioinformatics analysis and experimental validation

Background

Phosphatidylinositol binding clathrin assembly protein interacting mitotic regulator (PIMREG) expression is upregulated in a variety of cancers. However, its potential role in breast cancer (BC) remains uncertain.

Methods

The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to gather relevant information. The expression of PIMREG and its clinical implication in BC were assessed by using Wilcoxon rank-sum test. The prognostic value of PIMREG in BC was evaluated through the Cox regression model and nomogram, and visualized by Kaplan-Meier survival curves. Genes/proteins that interact with PIMREG in BC were also identified through GeneMANIA and MaxLink. Gene set enrichment analysis (GSEA) was then performed. The correlations of the immune cell infiltration and immune checkpoints with the expression of PIMREG in BC were explored via TIMER, TISIDB, and GEPIA. Potential drugs that interact with PIMREG in BC were explored via Q-omic. The siRNA transfection, CCK-8, and transwell migration assay were conducted to explore the function of PIMREG in cell proliferation and migration.

Results

PIMREG expression was significantly higher in infiltrating ductal carcinoma, estrogen receptor negative BC, and progestin receptor negative BC. High expression of PIMREG was associated with poor overall survival, disease-specific survival, and progression-free interval. A nomogram based on PIMREG was developed with a satisfactory prognostic value. PIMREG also had a high diagnostic ability, with an area under the curve of 0.940. Its correlations with several immunomodulators were also observed. Immune checkpoint CTLA-4 was significantly positively associated with PIMREG. HDAC2 was found as a potentially critical link between PIMREG and BRCA1/2. In addition, PIMREG knockdown could inhibit cell proliferation and migration in BC.

Conclusions

The high expression of PIMREG is associated with poor prognosis and immune checkpoints in BC. HDAC2 may be a critical link between PIMREG and BRCA1/2, potentially a therapeutic target.

Electrochemotherapy vs radiotherapy in the treatment of primary cutaneous malignancies or cutaneous metastases from primary solid organ malignancies: A systematic review and narrative synthesis

BACKGROUND

Electrochemotherapy has gained international traction and commendation in national guidelines as an effective tool in the management of cutaneous malignancies not amenable to surgical resection. Despite this, no level 5 evidence exists comparing it to radiotherapy in the treatment of cutaneous malignancies. This systematic review aimed to examine the literature directly and indirectly comparing electrochemotherapy and radiotherapy in the treatment of primary cutaneous malignancies or cutaneous metastases from primary solid organ malignancies.

MATERIALS & METHODS

The protocol for this review was registered on the PROSPERO International Prospective Register of Systematic Reviews with the protocol ID CRD42021285415. Searches of MEDLINE, Embase, CINAHL, CENTRAL and ClinicalTrials.gov databases were undertaken from database inception to 28 December 2021. Studies in humans comparing treatment with electrochemotherapy to radiotherapy and reporting tumour response with a minimum four week follow-up were eligible. Risk of bias was assessed using the ROBINS-I tool. Results are provided as a narrative synthesis.

RESULTS

Two case series with a total of 92 patients were identified as relevant to this study. Both case series examined patients with cutaneous squamous cell carcinoma. One case series examined elderly patients with predominantly head/neck lesions. The other examined younger patients with predominantly limb lesions who had cutaneous squamous cell carcinoma directly attributable to a rare skin condition.

CONCLUSION

There is little literature presenting comparative data for electrochemotherapy and radiotherapy in the treatment of primary cutaneous malignancies or cutaneous metastases. Included studies were marred by serious risk of bias particularly due to confounding. The inherent bias and heterogeneity of the included studies precluded synthesis of a consolidated comparison of clinical outcomes between the two therapies. Further research is required in this domain in the form of clinical trials and observational studies to inform guidelines for electrochemotherapy treatment.

Pulsed Electric Fields in Oncology: A Snapshot of Current Clinical Practices and Research Directions from the 4th World Congress of Electroporation

The 4th World Congress of Electroporation (Copenhagen, 9-13 October 2022) provided a unique opportunity to convene leading experts in pulsed electric fields (PEF). PEF-based therapies harness electric fields to produce therapeutically useful effects on cancers and represent a valuable option for a variety of patients. As such, irreversible electroporation (IRE), gene electrotransfer (GET), electrochemotherapy (ECT), calcium electroporation (Ca-EP), and tumour-treating fields (TTF) are on the rise. Still, their full therapeutic potential remains underappreciated, and the field faces fragmentation, as shown by parallel maturation and differences in the stages of development and regulatory approval worldwide. This narrative review provides a glimpse of PEF-based techniques, including key mechanisms, clinical indications, and advances in therapy; finally, it offers insights into current research directions. By highlighting a common ground, the authors aim to break silos, strengthen cross-functional collaboration, and pave the way to novel possibilities for intervention. Intriguingly, beyond their peculiar mechanism of action, PEF-based therapies share technical interconnections and multifaceted biological effects (e.g., vascular, immunological) worth exploiting in combinatorial strategies.

Electrochemotherapy with intravenous bleomycin for heavily pre-treated vulvar cancer patients

OBJECTIVE

The management of vulvar cancer recurrences is complicated by patients' advanced age and comorbidities. Bleomycin-based electrochemotherapy is a potential treatment option in this setting. However, no data on long-term outcomes are available. Therefore, a multicenter observational study was designed to evaluate the 5-year results in these patients.

METHODS

Data about patients and tumor characteristics, electrochemotherapy cycles, clinical response, and follow-up were recorded. Treatment procedures were performed according to the European Standard Operating Procedures of Electrochemotherapy (ESOPE) guidelines. Response was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) criteria.

RESULTS

Fifty-one patients (mean age 82.31±7.28 years) with squamous cell vulvar cancer underwent electrochemotherapy (median number of sessions 1; range 1-4). 20 patients had complete response and 32% of these were disease-free after 2 years (median progression-free survival 16.8 months). In 13 patients with partial response the median progression-free survival was 15.36 months, while patients with stable or progressive disease showed tumor relapse after 6.95 and 3.26 months, respectively (p<0.001). Median overall survival was 18.77, 13.07, 6.73, and 11.13 months in patients with complete response, partial response, stable disease, and progressive disease, respectively (p=0.001).

CONCLUSION

Long-term follow-up of vulvar cancer patients showed reasonable tumor control after electrochemotherapy and improved progression-free survival and overall survival in responder subjects compared with non-responders. Further studies aimed at improving local response after electrochemotherapy are warranted. Thus, this approach represents a potential alternative for these patients.

Electrochemotherapy for the treatment of cutaneous squamous cell carcinoma: The INSPECT experience (2008-2020)

Introduction

Cutaneous squamous cell carcinoma (cSCC) is a frequent skin cancer with a high risk of recurrence characterized by tumor infiltration and, in advanced cases, a poor prognosis. ECT (electrochemotherapy) is an alternative treatment option for locally advanced or recurrent cSCC that is unsuitable for surgical resection. In this study, we aimed to evaluate the data in the InspECT (International Network for Sharing Practice on ECT) registry of the referral centers and to clarify the indications for the use of ECT as a treatment modality for cSCC.

Materials and methods

Patients with primary, recurrent or locally advanced cSCC from 18 European centers were included. They underwent at least one ECT session with bleomycin between February 2008 and November 2020, which was performed following the European Standard Operating Procedures.

Results

The analysis included 162 patients (mean age of 80 years; median, 1 lesion/patient). Side effects were mainly local and mild (hyperpigmentation, 11%; ulceration, 11%; suppuration, 4%). The response to treatment per patient was 62% complete and 21% partial. In the multivariate model, intravenous drug administration and small tumor size showed a significant association with a positive outcome (objective response). One-year local progression-free survival was significantly better (p<0.001) in patients with primary tumors (80% (95% C.I. 70%-90%) than in patients with locally advanced disease (49% (95% C.I. 30%-68%).

Conclusion

In the present study, ECT showed antitumor activity and a favorable safety profile in patients with complex cSCC for whom there was no widely accepted standard of care. Better results were obtained in primary and small tumors (<3 cm) using intravenous bleomycin administration.

Management of malignant cutaneous wounds in oncologic patients

PURPOSE

Neoplastic wounds may develop as a result of primary tumor growth in the skin, due to metastasis, or due to skin invasion by tumors emerging from deeper levels. Malignant wounds may present as a crater-like ulcer, or as raised nodules with a cauliflower-like appearance. They are associated with malodor, necrosis, pain, bleeding, and secondary infection. The aim of our study is to better characterize fungating wounds and their management.

METHODS

We retrospectively reviewed the database of the Wound Care Unit of the University of Bologna in order to identify individuals affected by neoplastic wound, between January 2019 and February 2021.

RESULTS

We identified 9 females and 2 males with a mean age of 63 years; all were referred by the Oncology Unit. Management differed depending on the characteristics of the patients and the ulcers. Complete healing of the wound, following the parallel complete remission of the lymphoproliferative neoplasia, was observed in one individual. Among the others, one died because of breast cancer, while cutaneous lesions in 2 individuals deteriorated after 1 year of follow-up. Remission/relapse of the ulcer following the treatment course administered for the lymphoma were observed in one patient.

CONCLUSIONS

Treatment of malignant fungating wounds is challenging. Considering the neoplastic nature of the wounds, complete healing or improvement cannot be expected with the application of classically prescribed dressing for wounds. A mostly palliative treatment, focusing on maintaining the patient's quality of life, is a reasonable choice.

Electrochemotherapy for solid tumors: literature review and presentation of a novel endoscopic approach

BACKGROUND

Electrochemotherapy (ECT) is a minimally invasive and safe treatment gaining positive and long-lasting antitumoral results that are receiving the attention of the scientific community. It is a local treatment that combines the use of electroporation and the administration of cytotoxic drugs to induce cell death in the target tissue. ECT is largely used for the treatment of cutaneous and subcutaneous lesions, and good results have been reported for the treatment of deep visceral tumors. The latest literature review is provided. Moreover, in line with its development for the treatment of visceral tumors in this article, we describe a novel approach of ECT: endoscopic treatment of colorectal cancer. Endoscopic ECT application was combined with systemic chemotherapy in the treatment of obstructing rectal cancer without prospective surgery. A good response after ECT was described: concentric involvement of the rectum was reduced, and no stenosing lesions were detected.

CONCLUSIONS

Clinical studies have demonstrated that ECT is a very effective treatment for tumors of different histologic types and localizations. Endoscopic treatment for gastrointestinal cancer is an innovative application of ECT. The combination of systemic treatment and ECT was safe and highly effective in the treatment of colorectal cancer, especially when obstructive, giving the patient a significant gain in quality of life.

Electrochemotherapy of skin metastases from malignant melanoma: a PRISMA-compliant systematic review

The main treatment of MM metastases are systemic therapies, surgery, limb perfusion, and intralesional talimogene laherparepvec. Electrochemotherapy (ECT) is potentially useful also due to the high response rates recorded in cancers of any histology. No randomized studies comparing ECT with other local therapies have been published on this topic. We analyzed the available evidence on efficacy and toxicity of ECT in this setting. PubMed, Scopus, and Cochrane databases were screened for paper about ECT on MM skin metastases. Data about tumor response, mainly in terms of overall response rate (ORR), toxicity (both for ECT alone and in combination with systemic treatments), local control (LC), and overall survival (OS) were collected. The methodological quality was assessed using a 20-item validated quality appraisal tool for case series. Overall, 18 studies were included in our analysis. In studies reporting “per patient” tumor response the pooled complete response (CR) was 35.7% (95%CI 26.0–46.0%), and the pooled ORR was 80.6% (95%CI 68.7–90.1%). Regarding “per lesion” response, the pooled CR was 53.5% (95%CI 42.1–64.7%) and the pooled ORR was 77.0% (95%CI 56.0–92.6%). One-year LC rate was 80%, and 1-year OS was 67–86.2%. Pain (24.2–92.0%) and erythema (16.6–42.0%) were the most frequent toxicities. Two studies reported 29.2% and 41.6% incidence of necrosis. ECT is effective in terms of tumor response and tolerated in patients with skin metastases from MM, albeit with a wide variability of reported results. Therefore, prospective trials in this setting are warranted.

Adjuvant skin-sparing electrochemotherapy in a breast cancer patient with a prosthetic implant: 5-year follow-up outcomes

A 55-year-old woman with previous skin-sparing mastectomy and prosthetic reconstruction for multifocal ductal carcinoma developed homolateral axillary recurrence. Following nodal dissection, partial periprosthetic capsulectomy and the overlying breast skin excision, the pathology report revealed a positive cutaneous margin. Since further breast skin excision or radiotherapy would have compromised the prosthetic implant, and the patient was adamant about avoiding any endangering intervention, the multidisciplinary recommendation included skin-directed electrochemotherapy (ECT) in the frame of a multimodal treatment strategy. The procedure lasted 20 minutes under mild general sedation and included a bolus of intravenous bleomycin followed by local application of electric pulses using a needle electrode. The postprocedural course was uneventful, except for mild dermatologic toxicity. At 5 years, the patient is disease-free with the implant in situ. This report illustrates the proof-of-concept of adjuvant skin-sparing ECT to sterilize resection margins, preserve a breast implant and highlight procedural details to avert toxicity.

Influence of extremely low-frequency magnetic field on chemotherapy and electrochemotherapy efficacy in human Caco-2 colon cancer cells

Although chemotherapy (CT) has some adverse effects on healthy tissues and cells, it is widely preferred for treating patients with cancer. Drug resistance is one of the major impediments to successful cancer treatment. Electrochemotherapy (ECT) is a technique where cancer cells are rendered permeable to medications. Thanks to this permeability, the dose of the medication required for cancer treatment decreases. Our aim in this study is to examine the effects of short-term extremely low-frequency magnetic fields (ELF-MFs) on CT and ECT treatments in Caco-2 colon cancer cells. The Caco-2 cancer cells were treated with 5-fluorouracil (5-FU, 50 µM) and ECT (strength:1125 V/cm, duration:100 µs, frequency:1 Hz), alone as well as in combinations with ELF-MF (4 mT, 10 min). MTT assay was used to determine the efficacy of the treatments. Our findings in the study showed that ECT was much more successful than 5-FU treatment alone in Caco-2 colon cancer cells. Application of 4 mT ELF-MF after CT significantly increased the viability of the Caco-2 cancer cells compared to the CT group alone (p < .05). An increase in the viability of cells treated with 4 mT after ECT was observed compared to ECT alone. Similarly, there was an increase in the viability of cells treated with MF prior to ECT treatment (p < .05). The results show that exposure to ELF-MF at 4 mT flux density significantly reduces CT and ECT treatment efficacy in Caco-2 colon cancer cells.

Electrochemotherapy of Deep-Seated Tumors: State of Art and Perspectives as Possible "EPR Effect Enhancer" to Improve Cancer Nanomedicine Efficacy

Simple Summary

Electroporation-based therapies (reversible electroporation, irreversible electroporation, electrochemotherapy) are used for the selective treatment of deep-seated tumors. The combination of the structural modifications of the lipid bilayer of cell membranes, due to the application of electrical pulses in the targeted tissue, with the concomitant systemic (intravenous) administration of drugs can be considered as a sort of bridge between local-regional and systemic treatments. A possible further application of these techniques can be envisaged in their use as enhancers of the so-called “enhanced permeability and retention” effect. The intratumoral uptake of drug-loaded nanocarriers concomitant with the application of electric pulses in the target tumor is a new scenario worthy of attention and can represent a potential new frontier for drug delivery in oncology.

Abstract

Surgical resection is the gold standard for the treatment of many kinds of tumor, but its success depends on the early diagnosis and the absence of metastases. However, many deep-seated tumors (liver, pancreas, for example) are often unresectable at the time of diagnosis. Chemotherapies and radiotherapies are a second line for cancer treatment. The “enhanced permeability and retention” (EPR) effect is believed to play a fundamental role in the passive uptake of drug-loaded nanocarriers, for example polymeric nanoparticles, in deep-seated tumors. However, criticisms of the EPR effect were recently raised, particularly in advanced human cancers: obstructed blood vessels and suppressed blood flow determine a heterogeneity of the EPR effect, with negative consequences on nanocarrier accumulation, retention, and intratumoral distribution. Therefore, to improve the nanomedicine uptake, there is a strong need for “EPR enhancers”. Electrochemotherapy represents an important tool for the treatment of deep-seated tumors, usually combined with the systemic (intravenous) administration of anticancer drugs, such as bleomycin or cisplatin. A possible new strategy, worthy of investigation, could be the use of this technique as an “EPR enhancer” of a target tumor, combined with the intratumoral administration of drug-loaded nanoparticles. This is a general overview of the rational basis for which EP could be envisaged as an “EPR enhancer” in nanomedicine.

Electrochemotherapy in Vulvar Cancer and Cisplatin Combined with Electroporation. Systematic Review and In Vitro Studies

Simple Summary

Electrochemotherapy (ECT) is an emerging treatment for solid tumors and an attracting research field due to its clinical results. ECT in association with bleomycin is an effective and safe treatment option in the vulvar cancer palliative setting. With regard to cisplatin (CSP)-based ECT, considering the clear evidence on its efficacy in gynecological tumors, the possibility to improve local control with CSP-based ECT is intriguing and a well-designed randomized clinical trial should be addressed to this issue.

Abstract

Electrochemotherapy (ECT) is an emerging treatment for solid tumors and an attractive research field due to its clinical results. This therapy represents an alternative local treatment to the standard ones and is based on the tumor-directed delivery of non-ablative electrical pulses to maximize the action of specific cytotoxic drugs such as cisplatin (CSP) and bleomycin (BLM) and to promote cancer cell death. Nowadays, ECT is mainly recommended as palliative treatment. However, it can be applied to a wide range of superficial cancers, having an impact in preventing or delaying tumor progression and therefore in improving quality of life. In addition, during the natural history of the tumor, early ECT may improve patient outcomes. Our group has extensive clinical and research experience on ECT in vulvar tumors in the palliative setting, with 70% overall response rate. So far, in most studies, ECT was based on BLM. However, the potential of CSP in this setting seems interesting due to some theoretical advantages. The purpose of this report is to: (i) compare the efficacy of CSP and BLM-based ECT through a systematic literature review; (ii) report the results of our studies on CSP-resistant squamous cell tumors cell lines and the possibility to overcome chemoresistance using ECT; (iii) discuss the future ECT role in gynecological tumors and in particular in vulvar carcinoma.

Quality of Life with Vulvar Carcinoma Treated with Palliative Electrochemotherapy: The ELECHTRA (ELEctroCHemoTherapy vulvaR cAncer) Study

Simple Summary

A multicenter prospective observational study was conducted on patients with vulvar cancer (VC) refractory or not amenable to standard therapies undergoing palliative electrochemotherapy (ECT) as per clinical practice. Electrochemotherapy with bleomycin improves quality of life in patients with recurrent vulvar cancer. The assessment was performed with a visual analog pain scale (VAS), EuroQol 5-Dimension 5-Level (EQ-5D-L5) and Functional Assessment of Cancer Therapy—Vulva cancer (FACT—V). To our knowledge, this is the first study reporting the impact of palliative ECT on QoL of VC patients, with a detailed evaluation of potential correlations between tumor characteristics and severity of and response to symptoms. This improvement is higher in patients with clinical response and for smaller and anterior lesions. Based on these results, ECT in VC should be considered as an effective option based on the favorable outcomes both in terms of response and QoL.

Abstract

The ELECHTRA (ELEctroChemoTherapy vulvaR cAncer) project was conceived to collect data on palliative electrochemotherapy (ECT) in vulvar cancer (VC) assessing patients’ outcomes (response and survival) and impact on quality of life (QoL). After reporting outcome data in 2019, here, we present the results on QoL. A multicenter prospective observational study was conducted on patients with VC refractory or not amenable to standard therapies undergoing palliative ECT as per clinical practice. The following questionnaires were administered before and after ECT (two and four months later, early and late follow-up): visual analog pain scale (VAS), EuroQol 5-Dimension 5-Level (EQ-5D-L5) and Functional Assessment of Cancer Therapy—Vulva cancer (FACT—V). Analyses were conducted on both the whole study population and by subgroups (clinical response after ECT and site, number and size of lesions). Questionnaires from 55 patients were evaluated. Compared to the baseline (6.1 ± 2.1), the VAS was significantly reduced at early (4.3 ± 2.5) and late follow-up (4.6 ± 2.8) (p < 0.0001). The FACT—V score improved significantly at early (9.6 ± 4.0) (p < 0.0001) and late follow-up (8.9 ± 4.1) (p < 0.0054) as compared to the baseline (7.1 ± 3.6). No EQ-5D-5L statistically significant changes were observed. Subgroup analyses showed worse QoL in patients with stable or progressive disease, posterior site and multiple or larger than 3 cm nodules. This is the first study reporting improved QoL in VC patients after palliative ECT. Based on these results, ECT in VC should be considered an effective option based on the favorable outcomes both in terms of response and QoL.