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Veterinary sciences2026; 13(7); 691; doi: 10.3390/vetsci13070691

Electrochemotherapy Following Surgical Cytoreduction for the Treatment of Recurrent Equine Sarcoids: A Retrospective Study of 23 Lesions.

Abstract: Despite the wide range of therapeutic options currently available for equine sarcoids, recurrence of these lesions remains a major clinical challenge. Consequently, the identification of effective strategies for the management of recurrent sarcoids remains an important objective in equine oncology. The aim of this retrospective study was to evaluate the clinical outcome of surgical cytoreduction combined with intraoperative electrochemotherapy in horses affected by recurrent equine sarcoids. Medical records of horses treated between July 2018 and August 2025 at the Veterinary Teaching Hospital of the University of Bologna were retrospectively reviewed. Data collected included signalment, lesion location, clinical subtype, lesion size, chemotherapeutic agent used, recurrence status, and follow-up duration. Fourteen horses presenting 23 recurrent sarcoid lesions met the inclusion criteria. Recurrence was evaluated at both the lesion and horse levels. Local tumour control was achieved in 16 of 23 lesions (69.6%). Recurrence was observed in 7 lesions, corresponding to a lesion-based recurrence rate of 30.4%, and in 5 of 14 horses (35.7%). Malignant and fibroblastic lesions showed higher recurrence rates than other clinical subtypes, whereas larger lesions tended to recur more frequently than smaller lesions. No significant differences were identified between cisplatin- and carboplatin-treated lesions. Surgical cytoreduction combined with intraoperative electrochemotherapy provided encouraging local tumour control in a population composed exclusively of recurrent sarcoids. This treatment protocol may represent a valuable therapeutic option for horses with local recurrence of sarcoids, although larger prospective studies are required to further define prognostic factors and long-term outcomes.
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Publication Date: 2026-07-16 PubMed ID: 42514702PubMed Central: PMC13418348DOI: 10.3390/vetsci13070691Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study analyzed the effectiveness of combining surgical removal and electrochemotherapy to treat recurrent equine sarcoids, a common skin tumor in horses, and found this approach resulted in good local control in the majority of treated lesions.

Background

  • Equine sarcoids are skin tumors in horses that often recur despite various available treatments.
  • Recurrent sarcoids are a significant clinical problem in equine oncology, necessitating improved management strategies.
  • Electrochemotherapy involves applying electrical pulses to tumors to increase chemotherapy drug uptake and improve treatment efficacy.
  • This study focused on evaluating surgical cytoreduction (removal of most tumor tissue) combined with intraoperative electrochemotherapy for recurrent sarcoids.

Study Design and Methods

  • This was a retrospective study reviewing medical records from July 2018 to August 2025 at the Veterinary Teaching Hospital of the University of Bologna.
  • Inclusion criteria: horses with recurrent sarcoids who underwent surgical cytoreduction followed by intraoperative electrochemotherapy.
  • Data collected included:
    • Horse signalment (age, breed, sex)
    • Lesion location on the horse
    • Clinical subtype of sarcoid (e.g., malignant, fibroblastic)
    • Size of lesions
    • Type of chemotherapy agent used (cisplatin or carboplatin)
    • Recurrence status during follow-up
    • Duration of follow-up
  • Recurrence was evaluated at both individual lesion and horse levels.

Results

  • 14 horses with 23 recurrent sarcoid lesions were included.
  • Local tumor control was achieved in 16 out of 23 lesions, indicating a 69.6% success rate.
  • Recurrence occurred in:
    • 7 lesions (30.4% lesion-level recurrence rate)
    • 5 horses (35.7% horse-level recurrence rate)
  • Higher recurrence rates were observed in malignant and fibroblastic sarcoid subtypes compared to other types.
  • Larger lesions tended to recur more often than smaller ones.
  • No statistically significant difference in recurrence was found between lesions treated with cisplatin versus carboplatin.

Conclusions and Implications

  • The combination of surgical cytoreduction and intraoperative electrochemotherapy showed encouraging local tumor control in recurrent equine sarcoids.
  • This treatment approach may be a valuable option for managing horses with locally recurrent sarcoids.
  • Because the study was retrospective and involved a relatively small number of cases, further larger prospective studies are needed.
  • Future research should focus on:
    • Confirming prognostic factors that influence treatment success
    • Evaluating long-term outcomes and recurrence rates over extended follow-up periods
    • Comparing the effectiveness of different chemotherapeutic agents in electrochemotherapy protocols
  • Overall, this study provides promising evidence that combining surgery with electrochemotherapy may improve treatment results in challenging recurrent equine sarcoids.

Cite This Article

APA
Spadari A, Meistro F, Tornago R, Facchetti C, D'Angelo P, Ralletti MV, Montemagno S, Rinnovati R. (2026). Electrochemotherapy Following Surgical Cytoreduction for the Treatment of Recurrent Equine Sarcoids: A Retrospective Study of 23 Lesions. Vet Sci, 13(7), 691. https://doi.org/10.3390/vetsci13070691

Publication

Veterinary sciences
ISSN: 2306-7381
NlmUniqueID: 101680127
Country: Switzerland
Language: English
Volume: 13
Issue: 7
PII: 691

Researcher Affiliations

Spadari, Alessandro
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
Meistro, Federica
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
Tornago, Raimondo
  • Independent Researcher, 39012 Merano, Italy.
Facchetti, Cristian
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
D'Angelo, Paola
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
Ralletti, Maria Virginia
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
Montemagno, Salvatore
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.
Rinnovati, Riccardo
  • Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, 40064 Bologna, Italy.

Conflict of Interest Statement

The authors declare no conflicts of interest.

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