Therapeutic responses, prognostic factor and therapeutic strategy evaluation for canine lymphoma

• Main Authors: Shang-Lin Wang, 王尚麟
• Other Authors: 廖泰慶
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/98191847741788948797

博士 === 國立臺灣大學 === 獸醫學研究所 === 104 === Lymphoma is one of the common neoplasms in dogs. CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone) is the most used chemotherapy for treating canine lymphoma. In order to provide better therapeutic quality and longer survival time in lymphoma patients, this study discussed the prognostic factor for therapeutic evaluation, design of new chemotherapy protocol, possible reasons for the failure of conventional chemotherapy, and the efficacy of new chemotherapy drugs. Most prognostic factors of lymphoma were evaluated at diagnosis and before treatment. Prognostic factors after chemotherapy have not been widely reported for lymphoma treatment. We chose “chemotherapy-induced neutropenia” for prognostic factor evaluation. The result revealed that median first remission times in the neutropenia and no neutropenia groups were 812 and 219 days, respectively (P < 0.01). The median survival times were 952 and 282 days, respectively (P < 0.01). Dogs with lymphoma that had chemotherapy-induced neutropenia exhibited significantly increased remission and survival times. Therefore, “chemotherapy-induced neutropenia” can be a positive prognostic factor. The side effects of doxorubicin used in CHOP protocol are usually very severe. We used mitoxantrone instead of doxorubicin to design a new CMOP induction protocol. Forty-four multicentric lymphoma dogs were treated with CHOP or CMOP induction protocol. The median progression-free survival in the CHOP and CMOP groups were 222 and 162 days, respectively (P = 0.75). The median survival time were 318 and 242 days, respectively (P = 0.63). Anorexia and diarrhea episodes were significantly higher in the CHOP group than in the CMOP group (P = 0.02 and P = 0.01, respectively). Our results suggest that CMOP protocol may be another treatment choice for canine lymphoma. Finally, we discussed the most relapsed time point in CHOP protocol. When we treated sixty-eight lymphoma dogs, we analysed the data of forty-one relapsed patients. Our result showed that relapse occurred more frequently after administration of cyclophosphamide compared with vincristine or doxorubicin (P < 0.01). Therefore, the therapeutic outcome of traditional CHOP-based chemotherapy may be improved by replacing cyclophosphamide with other cytotoxic drugs. We also compared the cytotoxic effect of new alkylating agent BO-2094 and cyclophosphamide to canine lymphoma cells by cellular assay. The results showed that BO-2094 has significant cytotoxic ability than cyclophosphamide to lymphoma cells in vitro. Further studies may be needed to approve its clinical value.