Biphasic pulses enhance bleomycin efficacy in a spontaneous canine genital tumor model of chemoresistance: Sticker sarcoma
© Spugnini et al; licensee BioMed Central Ltd. 2008
Received: 23 September 2008
Accepted: 03 November 2008
Published: 03 November 2008
Sticker's sarcoma (also known as transmissible venereal tumor) is a horizontally transmitted neoplasm of the dog, that is passed with coitus. It is a locally aggressive tumor with a low tendency to metastatic spread. The most common locations are the genitals, the nose, the perianal area. Standard treatment consists with chemotherapy with vincristine, however other therapies such as, cryotherapy, immunotherapy or, in selected cases, radiation therapy, have been reported. In this article we describe the outcome of a small cohort of canine patients, with chemotherapy resistant transmissible venereal tumor (TVT), treated with bleomycin selectively driven by trains of biphasic pulses (electrochemotherapy). Three canine patients, with refractory TVT, entered the study and received two sessions of ECT under sedation. The pets had local injection of bleomycin at the concentration of 1.5 mg/ml and five minutes after the chemotherapy, trains of 8 biphasic electric pulses lasting 50 + 50 μs each, with 1 ms interpulse intervals, were delivered by means of modified caliper or, for difficult districts, through paired needle electrode. All the patients responded to the treatment and are still in remission at different times. Electrochemotherapy appears as a safe and efficacious modality for the treatment of TVT and warrants further investigations.
Canine Sticker's tumor is a coitus transmissible disease that is directly transferred from dog to dog through major histocompatibility complex barriers and by means of direct transfer of viable tumor cells from individual to individual . The transfer is facilitated by the presence of mucosal lesions (like those occurring during mating), and can be transmitted by behaviors such as licking or sniffing . Interestingly, the transmissible agent causing transmissible venereal tumor (TVT) is thought to be the tumor cell itself. Recent articles analyzed several genetic markers including major histocompatibility (MHC) genes, in Sticker's sarcomas and matched blood samples [2, 3]. In each case, the tumor resulted genetically distinct from its host [2, 3]. During progressive growth, TVT downmodulates MHC antigen expression and release inhibiting cytokines that impair the NK function, frequently resulting in host's inability to reject the tumor [4–6]. The treatment of election for these neoplasms is chemotherapy with vincristine however, cryotherapy, immunotherapy and, in selected cases, radiation therapy have been reported as well [1, 7–10]. A recently published paper reports a response rate to vincristine of 31 out of 38 dogs, the non responders were treated with doxorubicin; at the completion of the chemotherapy cycles two dogs still had viable tumor cells .
Biphasic pulses electrochemotherapy (ECT) is a novel anticancer technique that has been recently investigated in oncology [11, 12]. More recently, our group has investigated the feasibility and efficacy of ECT in companion animals carrying spontaneously occurring neoplasms, obtaining an high percentage of responses, many of which long lasting, even in neoplasms, such as lymphoma and soft tissue sarcomas, known to be non-responsive to bleomycin, the drug of election [13–29].
On the basis of such results, a study was performed to assess the potentials of this technique for the treatment or palliation of canine TVTs that were resistant to systemic chemotherapy due to the difficulties posed by treating tumors in the genital district.
Materials and methods
Privately owned veterinary patients with histopathologically confirmed localized TVT were selected for the study. Previous informed consent was obtained from the owners, according to the Italian law (116/92). In order to be enrolled, the patients had to have normal renal and hepatic function (normal serum blood urea nitrogen [BUN], creatinine and urine specific gravity as well as normal liver enzymes and bile acids). Moreover, patients had to be free of underlying life threatening diseases or other medical complications (i.e. diabetes mellitus).
Individual data and response to electrochemotherapy (ECT) in three dogs with TVT
Signalment (age, sex,)
Tumor type and stage
4 yo, M, Hunting dog
5 yo, M, Mixed Breed
7 yo, M, German Shephard
Patients that entered in the study received two sessions of ECT one week apart under sedation with medetodimine and ketamine as per manufacturer's instruction. Briefly the tumor's bed and the margins for 0.5 cm in all directions were infiltrated with bleomycin at the concentration of 1.5 mg/ml. Five minutes after the infiltration, trains of 8 biphasic electric pulses lasting 50 + 50 μs each, with 1 ms interpulse intervals, were delivered by means of modified caliper electrodes. For particularly difficult districts, paired needle array electrodes were adopted.
Tumor response criteria
Complete Remission (CR) – the disappearance of all evidence of cancer in all sites for a defined period of time.
Partial Remission (PR) – the decrease in size of all tumors by 50% or greater as measured by the sum of the product of two diameters of each tumor for a defined period of time.
Stable Disease (SD) – the decrease of < 50% or an increase of < 25% in the sum of the product of two diameters for a defined period of time.
Progressive Disease (PD) – the increase of 25% or more in the sum of the product of two diameters for a defined period of time.
The "Chemopulse" is built up by a toroidal core transformer generating a roughly rectangular pulse which is split in two halves that are sequentially driven to obtain a biphasic pulse. The pulses are not singularly produced but are created in bursts of eight, thus reducing the treatment time and the overall patient morbidity. The equipment allows to choose among a broad range of voltages (from 450 to 2450 V) with sequential increases of 200 V and permits to regulate the number of pulses (from 1 to 16) and the duration of the pulses (50 to 100 μs). The standard setting is 8 pulses of 50+50 μs at 1300 V/cm. The pulse repetition frequency is 1 Hz while the frequency of burst repetition is 1 kHz, resulting in a total burst duration of 7.1 ms [11, 13–29].
1) Modified monolateral compass electrode steel, bachelite, plastic with perforated metal plates. Dimensions (Length × Height × Width): 22 × 10 × 1 mm.
Vaccine type twin needle array electrode steel and plastic. Needle length: 20 mm; array diameter: 20 mm.
Electrochemotherapy is a novel technique for cancer treatment or palliation that showed high efficacy and low toxicity. Its ease of administration associated with its affordable cost that enables clinicians to treat again previously electroporated areas without side effects like cheloids, profuse bleeding, impaired wound healing like those observed in case of re-irradiation of tumors both in pets and humans [16, 24, 27], make it an appealing alternative to standard anticancer options. In the present study, electrochemotherapy, has proven to be a low toxicity therapy allowing local tumor control without significant local or systemic side effects. To the best of the authors' knowledge this is the first study on the adoption of ECT for the palliation/treatment of cytologically or histologically confirmed TVTs in a spontaneous canine genital tumor model. Despite the low number of enrolled patients, the long term responses obtained in all dogs with refractory disease are worth of mention. Further studies, investigating other tumor types involving the genitals, are needed to improve ECT control by exploring new protocols and drugs also in view of the possible translation of data to humans [24, 27].
This work has been supported by "Grant 2006" and "PROJECT FIRB/MUR (RBIPO6LCA9-009) Grant"of the Italian Ministry of Health to E.P.S and G.C., and by a FUTURA-onlus Grant and a Second University of Naples Grant to A.B.
- de Lorimier LP, Fan TM: Canine transmissible venereal tumor. Small animal clinical oncology. Edited by: Withrow SJ, Vail DM. 2007, New York; WB Saunders Co, 799-804. 4Google Scholar
- Murgia C, Pritchard JK, Kim SY, Fassati A, Weiss RA: Clonal origin and evolution of a transmissible cancer. Cell. 2006, 126: 477-487. 10.1016/j.cell.2006.05.051.View ArticleGoogle Scholar
- VonHoldt BM, Ostrander EA: The singular history of a canine transmissible tumor. Cell. 126: 445-447. 10.1016/j.cell.2006.07.016.Google Scholar
- Liao KW, Hung SW, Hsiao YW, Bennett M, Chu RM: Canine transmissible venereal tumor cell depletion of B lymphocytes: molecule(s) specifically toxic for B cells. Vet Immunol Immunopathol. 2003, 92: 149-162. 10.1016/S0165-2427(03)00032-1.View ArticleGoogle Scholar
- Hsiao YW, Liao KW, Hung SW, Chu RM: Tumor-infiltrating lymphocyte secretion of IL-6 antagonizes tumor-derived TGF-beta 1 and restores the lymphokine-activated killing activity. J Immunol. 2004, 172: 1508-1514.View ArticleGoogle Scholar
- Hsiao YW, Liao KW, Chung TF, Liu CH, Hsu CD, Chu RM: Interactions of host IL-6 and IFN-gamma and cancer-derived TGF-beta1 on MHC molecule expression during tumor spontaneous regression. Cancer Immunol Immunother. 2008, 57: 1091-1104. 10.1007/s00262-007-0446-5.View ArticleGoogle Scholar
- Nak D, Nak Y, Cangul IT, Tuna B: A Clinico-pathological study on the effect of vincristine on transmissible venereal tumour in dogs. J Vet Med A Physiol Pathol Clin Med. 2005, 52: 366-370.View ArticleGoogle Scholar
- Knapp DW, Richardson RC, Bottoms GD, Teclaw R, Chan TC: Phase I trial of piroxicam in 62 dogs bearing naturally occurring tumors. Cancer Chemother Pharmacol. 1992, 29: 214-218. 10.1007/BF00686255.View ArticleGoogle Scholar
- Hines-Peralta A, Liu ZJ, Horkan C, Solazzo S, Goldberg SN: Chemical tumor ablation with use of a novel multiple-tine infusion system in a canine sarcoma model. J Vasc Interv Radiol. 2006, 17: 351-358.View ArticleGoogle Scholar
- Ahmed M, Liu Z, Afzal KS, Weeks D, Lobo SM, Kruskal JB, Lenkinski RE, Goldberg SN: Radiofrequency ablation: effect of surrounding tissue composition on coagulation necrosis in a canine tumor model. Radiology. 2004, 230: 761-767. 10.1148/radiol.2303021801.View ArticleGoogle Scholar
- Daskalov I, Mudrov N, Peycheva E: Exploring new instrumentation parameters for electrochemotherapy. IEEE Engineering in Medicine and Biology. 1999, 18: 62-66. 10.1109/51.740982.View ArticleGoogle Scholar
- Peycheva E, Daskalov I, Tsoneva I: Electrochemotherapy of mycosis fungoides by interferon-α. Bioelectrochemistry. 2007, 70: 283-286. 10.1016/j.bioelechem.2006.10.006.View ArticleGoogle Scholar
- Spugnini EP, Porrello A: Potentiation of chemotherapy in companion animals with spontaneous large neoplasms by application of biphasic electric pulses. J Exp Clin Cancer Res. 2003, 22: 571-580.Google Scholar
- Spugnini EP, Citro G, Porrello A: Rational design of new electrodes for electrochemotherapy. J Exp Clin Cancer Res. 2005, 24: 245-254.Google Scholar
- Spugnini EP, Dragonetti E, Vincenzi B, Onori N, Citro G, Baldi A: Pulse mediated chemotherapy enhances local control and survival in a spontaneous canine model of primary mucosal melanoma. Melanoma Res. 2006, 16: 23-27. 10.1097/01.cmr.0000195702.73192.a0.View ArticleGoogle Scholar
- Spugnini EP, Baldi A, Vincenzi B, Bongiorni F, Bellelli C, Porrello A: Intraoperative versus postoperative electrochemotherapy in soft tissue sarcomas: a preliminary study in a spontaneous feline model. Cancer Chemother Pharmacol. 2007, 59: 375-381. 10.1007/s00280-006-0281-y.View ArticleGoogle Scholar
- Baldi A, Spugnini EP: Thoracic haemangiopericytoma in a cat. Vet Rec. 2006, 159: 598-600.View ArticleGoogle Scholar
- Spugnini EP, Vincenzi B, Baldi F, Citro G, Baldi A: Adjuvant electrochemotherapy for the treatment of incompletely resected canine mast cell tumors. Anticancer Res. 2006, 26 (6B): 4585-4589.Google Scholar
- Spugnini EP, Vincenzi B, Citro G, Santini D, Dotsinsky I, Mudrov N, Baldi A: Adjuvant electrochemotherapy for the treatment of incompletely excised spontaneous canine sarcomas. In Vivo. 2007, 21 (5): 819-822.Google Scholar
- Spugnini EP, Filipponi M, Romani L, Dotsinsky I, Mudrov N, Barone A, Rocco E, Laieta MT, Montesarchio V, Cassano R, Citro G, Baldi A: Local control and distant metastasis after electrochemotherapy of a canine anal melanoma. In Vivo. 2007, 21 (5): 897-899.Google Scholar
- Spugnini EP, Vincenzi B, Citro G, Tonini G, Dotsinsky I, Mudrov N, Baldi A: Electrochemotherapy for the treatment of squamous cell carcinoma in cats: A preliminary report. Vet J. 2007Google Scholar
- Spugnini EP, Citro G, Dotsinsky I, Mudrov N, Mellone P, Baldi A: Ganglioneuroblastoma in a cat: a rare neoplasm treated with electrochemotherapy. Vet J. 2008, 178 (2): 291-293. 10.1016/j.tvjl.2007.08.014.View ArticleGoogle Scholar
- Spugnini EP, Citro G, Mellone P, Dotsinsky I, Mudrov N, Baldi A: Electrochemotherapy for localized lymphoma: a preliminary study in companion animals. J Exp Clin Cancer Res. 2007, 26: 343-346.Google Scholar
- Spugnini EP, Baldi F, Mellone P, Feroce F, D'Avino A, Bonetto F, Vincenzi B, Citro G, Baldi A: Patterns of tumor response in canine and feline cancer patients treated with electrochemotherapy: preclinical data for the standardization of this treatment in pets and humans. J Transl Med. 2007, 5: 48-10.1186/1479-5876-5-48.View ArticleGoogle Scholar
- Spugnini EP, Dotsinsky I, Mudrov N, Cardosi G, Citro G, D'Avino A, Baldi A: Biphasic pulses enhance bleomycin efficacy in a spontaneous canine perianal tumors model. J Exp Clin Cancer Res. 2007, 26: 483-487.Google Scholar
- Spugnini EP, Vincenzi B, Betti G, Cordahi F, Dotsinski I, Mudrov N, Baldi A: Surgery and electrochemotherapy for the treatment of high grade soft tissue sarcoma in a dog. Vet Rec. 2008, 162 (6): 186-188.View ArticleGoogle Scholar
- Spugnini EP, Citro G, Baldi A: Potential role of electrochemotherapy for the treatment of soft tissue sarcoma: first insights from preclinical studies in animals. Int J Biochem Cell Biol. 2008, 40 (2): 159-163.View ArticleGoogle Scholar
- Spugnini EP, Dotsinsky I, Mudrov N, Bufalini M, Giannini G, Citro G, Feroce F, Baldi A: Adjuvant electrochemotherapy for incompletely excised anal sac carcinoma in a dog. In Vivo. 2008, 22: 47-50.Google Scholar
- Spugnini EP, Dotsinsky I, Mudrov N, De Luca A, Codini C, Citro G, D' Avino A, Baldi A: Successful rescue of a apocrine gland carcinoma metastatic to the cervical lymph nodes by mitoxantrone coupled with trains of permeabilizing electric pulses (electrochemotherapy). In Vivo. 2008, 22: 51-54.Google Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.