Local tumour response to neoadjuvant therapy with 2‐aminoethyl dihydrogen phosphate in dogs with soft tissue sarcoma

BACKGROUND: In cases of soft tissue sarcoma (STS), neoadjuvant therapy is indicated to downstage the tumour prior to surgery to achieve enhanced local tumour control. The antineoplastic phospholipid compound 2‐aminoethyl dihydrogen phosphate (2‐AEH2F) is an alkyl phosphate ester capable of inhibiting cell proliferation and inducing cell death by modifying the asymmetry of phospholipids in the cytoplasmic membrane OBJECTIVES: This clinical study was designed to investigate local antitumoural effects of neoadjuvant therapy with 2‐AEH2F in dogs with naturally occurring STS MATERIAL AND METHODS: Dogs (n = 11) received four consecutive weekly intravenous injections of 2‐AEH2F (70 mg/kg) prior to tumour resection. Tomographic (CT) and thermal (TE) images were used to investigate changes in tumour size and local temperature in response to treatment RESULTS: Comparative analysis of CT images (n = 9/11) failed to reveal complete or partial remission according to selected assessment criteria (RECIST, WHO and volumetric). Comparative analysis of TE images (n = 10/11) revealed significantly (p = 0.01416) lower temperatures in tumoural areas relative to surrounding tissues over the course of treatment CONCLUSIONS: 2‐AEH2F had no cytoreductive effects when used at doses and intervals described in this study. However, significant drop in skin temperatures recorded in tumoural areas suggest induction of physiological changes.