<abstract xmlns="http://www.w3.org/1999/xhtml"><sec><h3>Background</h3><p>Electrochemotherapy (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.</p></sec><sec><h3>Patients and methods</h3><p>We 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.</p></sec><sec><h3>Results</h3><p>According 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 &lt; 0.01).</p></sec><sec><h3>Conclusions</h3><p>Combined 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.</p></sec></abstract>

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.

Combined local and systemic bleomycin administration in electrochemotherapy to reduce the number of treatment sessions

Radiology and Oncology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

BackgroundElectrochemotherapy (ECT), a medical treatment widely used in human patients for tumor treatment, increases bleomycin toxicity by 1000 fold in the...

Patient	Breed	Location of the tumor	Weight (kg)	Histology	Stage	Size (cm3)	Response 1 (ECT)	Response 2 (ECT)
12	Cross-breed	Oral	30	Melanoma	I	158.2	PR	SD
13	Cross-breed	Oral	21	Sarcoma	III	79.76	PR	SD
14	Cross-breed	Oral	20	Carcinoma	III	96.5	PR	SD
15	Toy Poodle	Oral	5	Fibrosarcoma	II	23.23	PD	PD
16	Cross-breed	Oral	11	Melanoma	II	73.8	PR	SD
17	Cross-breed	Oral	16	Schwannoma	II	467.02	PD	SD
18	Cross-breed	Oral	6	Squamous cell carcinoma	II	12.32	SD	SD
19	Labrador retriever	Oral	32	Fibrosarcoma	II	40	PR	SD
20	Rottweiler	Oral	34	Melanoma	II	33	PR	PR
21	German Shepherd	Oral	39	Fibrosarcoma	II	101.18	PR	PD
22	Cross-breed	Oral	14	Melanoma	II	14.4	PR	PR

Patient	Breed	Location of the tumor	Weight (kg)	Histology	Stage	Size (cm3)	Response 1 (ECT)	Response 2 (S+L)
1	Labrador retriever	Oral	32	Mastocytoma	II	10.6	PR	CR
2	Cross-breed	Oral	21	Squamous cell carcinoma	II	36.2	SD	PR
3	Labrador retriever	Nasal	32	Squamous cell carcinoma	II	43.5	PR	CR
4	Yorkshire	Perianal	5	Solid differentiated carcinoma	IV	173.8	SD	SD
5	Cross-breed	Elbow	12	Schwannoma	I	67.6	SD	PR
6	Rottweiler	Oral	37	Fibrosarcoma	I	109.5	SD	CR
7	Labrador retriever	Nasal	38	Squamous cell carcinoma	III	42.4	SD	PR
8	Boxer	Oral	37	Fibrosarcoma	III	112.2	SD	PR
9	Cocker spaniel	Oral	15	Melanoma	II	8.7	PR	CR
10	Beagle	Oral	16	Melanoma	III	12.4	PR	CR
11	Cocker spaniel	Oral	16	Melanoma	III	26.64	PR	CR

Combined local and systemic bleomycin administration in electrochemotherapy to reduce the number of treatment sessions

Article Category: Research Article

Published Online: Feb 16, 2016

Page range: 58 - 63

Received: Oct 20, 2015

Accepted: Jan 18, 2016

DOI: https://doi.org/10.1515/raon-2016-0015

Keywords
electrochemotherapy, combined treatment, systemic and local, bleomycin, resistant

© 2016 Radiol Oncol

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1.

Figure 2.

List of group 2 patients (control) treated using a repetition of the first session

List of group 1 patients treated using combined systemic and local bleomycin administration in the second treatment session

Combined local and systemic bleomycin administration in electrochemotherapy to reduce the number of treatment sessions

Article Category: Research Article

Published Online: Feb 16, 2016

Page range: 58 - 63

Received: Oct 20, 2015

Accepted: Jan 18, 2016

DOI: https://doi.org/10.1515/raon-2016-0015

Keywordselectrochemotherapy, combined treatment, systemic and local, bleomycin, resistant

© 2016 Radiol Oncol

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1.

Figure 2.

List of group 2 patients (control) treated using a repetition of the first session

List of group 1 patients treated using combined systemic and local bleomycin administration in the second treatment session

Keywords
electrochemotherapy, combined treatment, systemic and local, bleomycin, resistant