Neoadjuvant and adjuvant doxorubicin chemotherapy in a case of feline soft tissue sarcoma

Abstract

Case summary A 7-year old male neutered domestic shorthair cat was presented with a 2 month history of a slow-growing mass on the right zygomatic area. A CT scan revealed a soft tissue mass in the right zygomatic region with no alterations of the underlying bone and features of local invasiveness. Cytology was suggestive of a mesenchymal tumour and histopathology from an incisional biopsy was consistent with a soft tissue sarcoma (STS). The cat was treated with neoadjuvant intravenous doxorubicin chemotherapy at a dose of 25 mg/m2, every two weeks. The patient experienced a partial response and underwent surgical excision of the tumour. Doxorubicin was continued as an adjuvant treatment for three further chemotherapy sessions, at a dose of 25 mg/m2 every 21 days. Local tumour recurrence was detected on clinical examination and cytologically confirmed 259 days following surgery. Relevance and novel information Treatment with neoadjuvant doxorubicin can be considered in cases of inoperable STSs in order to cytoreduce the tumour and improve the chances of achieving complete surgical margins. The role of adjuvant chemotherapy in this setting remains unclear.