BackgroundOral malignant melanoma is the most common, but aggressive oral cancer in dogs with poor prognosis. Electrochemotherapy (ECT) has therapeutic potential in such tumors as effective local treatment. Therefore, the aim of this prospective clinical study was to evaluate treatment effectiveness of ECT in as first line treatment for canine oral malignant melanoma, and search for factors influencing treatment outcome.MethodsSixty-seven canines with primary oral malignant melanoma, non-candidates for first-line therapy, were enrolled. All dogs received ECT and follow-up exams for the span of two years.ResultsBased on RECIST criteria, the objective response rate was 100%, 89.5%, 57.7%, and 36.4%, in stage I, II, III and IV, respectively. Only patients in stage I, II and III with partial or complete response improved their quality of life. The median time to progression was 11, 7, 4 and 4 months, and median survival time after the treatment was 16.5, 9.0, 7.5 and 4.5 months, for patients in stage I, II, III and IV, respectively. Significantly better was local response in stage I and II disease (p = 0.0013), without the bone involvement (p = 0.043)ConclusionsElectrochemotherapy is effective local treatment of oral canine malignant melanoma when no alternative treatment is available. Better response is expected in stage I and II patients with tumors without bone involvement.

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BackgroundElectrochemotherapy (ECT), a medical treatment widely used in human patients for tumor treatment, increases bleomycin toxicity by 1000 fold in the treated area with an objective response rate of around 80%. Despite its high response rate, there are still 20% of cases in which the patients are not responding. This could be ascribed to the fact that bleomycin, when administered systemically, is not reaching the whole tumor mass properly because of the characteristics of tumor vascularization, in which case local administration could cover areas that are unreachable by systemic administration.Patients and methodsWe propose combined bleomycin administration, both systemic and local, using companion animals as models. We selected 22 canine patients which failed to achieve a complete response after an ECT treatment session. Eleven underwent another standard ECT session (control group), while 11 received a combined local and systemic administration of bleomycin in the second treatment session.ResultsAccording to the WHO criteria, the response rates in the combined administration group were: complete response (CR) 54% (6), partial response (PR) 36% (4), stable disease (SD) 10% (1). In the control group, these were: CR 0% (0), PR 19% (2), SD 63% (7), progressive disease (PD) 18% (2). In the combined group 91% objective responses (CR+PR) were obtained. In the control group 19% objective responses were obtained. The difference in the response rate between the treatment groups was significant (p < 0.01).ConclusionsCombined local and systemic bleomycin administration was effective in previously to ECT non responding canine patients. The results indicate that this approach could be useful and effective in specific population of patients and reduce the number of treatment sessions needed to obtain an objective response.

We studied the effect of different storage conditions of porcine ovaries (time, temperature) on the characteristics of the follicular fluid, immature oocyte quality, meiotic competence and in vitro fertilization of oocytes. Ovaries were stored for 2, 4 or 6 h at 3 different temperatures (15˚C, 25˚C or 35˚C). As the storage time increased, pH and glucose concentration of the follicular fluid, percentage of live immature oocytes at germinal vesicle stage, oxidative activity and maturation rate decreased. At higher temperatures, pH and glucose concentration decreased, but oxidative activity and oocyte maturation rate increased. Lactate concentration and immature oocyte ROS production increased as storage time and temperature increased. The ovary storage for longer than 2 h at 25˚C and 35˚C resulted in low pH of the follicular fluid and high ROS level in immature oocytes. Such conditions seem to damage oocytes and impair their meiotic competence. A decrease in the oxidative activity caused by long time and/or low storage temperature may imply a decrease in oocyte vitality. In conclusion, in the porcine species, the transport of ovaries at 25˚C and 35˚C for 2 h are the best conditions to maintain adequate oocyte quality, meiotic competence and in vitro fertilization rates.