The effect of intralesional bleomycin on canine acanthomatous epulis

Abstract

Four dogs with recurrent acanthomatous epulis (AE) were injected with bleomycin (5 mg) intralesionally once a week. In three cases, tumors were clinically indistinguishable within three-to-eight weeks. In the fourth case, the tumor disappeared after 10 weekly injections. Through the administration period of bleomycin, no adverse reactions were recognized in any case. Electron microscopic examination together with a decrease in the percentage of mitotic cells implied that bleomycin might inhibit deoxyribonucleic acid (DNA) synthesis of tumor cells.

Acanthomatous ameloblastoma in dogs treated with intralesional bleomycin

“…AA is a benign tumour, but is locally aggressive and frequently invades the alveolar bone or recurs after marginal surgical excision 1,5 . AA is currently classified as an ameloblastoma; however, controversies exist as to whether this tumour should be classified as a basal cell carcinoma, epulis or an odontal origin tumour 3,6 …”

“…However, owners may decline surgery owing to health problems or to prevent resulting cosmetic defects. Radiation therapy has also been reported as effective in treating these tumour types, but this option may not be feasible for financial or logistical reasons 6 . Intralesional (IL) chemotherapy is another option for treating AA.…”

“…In 1998, Yoshida et al . studied the effectiveness of IL bleomycin on four dogs with AA; all the dogs studied had a positive response to the treatment 6 . Bleomycin is a chemotherapy made with a mixture of cytotoxic glycopeptide antibiotics from a strain of Streptomyces verticillus.…”

“…Bleomycin is a chemotherapy made with a mixture of cytotoxic glycopeptide antibiotics from a strain of Streptomyces verticillus. 7 Bleomycin binds to DNA and causes scission; thus, inhibiting synthesis 8 and may inhibit tumour cell proliferation by impairing DNA synthesis during the mitotic phases 6 . In AA, bleomycin causes vacuolar degeneration and tumour cell necrosis 6 .…”

“… 7 Bleomycin binds to DNA and causes scission; thus, inhibiting synthesis 8 and may inhibit tumour cell proliferation by impairing DNA synthesis during the mitotic phases 6 . In AA, bleomycin causes vacuolar degeneration and tumour cell necrosis 6 . In humans, bleomycin is typically administered subcutaneously, intramuscularly or intravenously weekly at 10–20 U m −2 8 .…”