Squamous cell carcinoma (SCC) is an epithelial neoplasm that arises from skin keratinocytes of the dogs. Its etiology is related to ultraviolet sunlight, which puts it as one of the most frequent neoplasm in tropical hot weather countries. Cutaneous SCC have a locally invasive, low metastatic behavior, and is often associated with actinic keratosis. This study aimed to evaluate the effect of pre-operative treatment with piroxicam (Px) on COX-2 and Ki67 expression, indicators of inflammation and cell proliferation, respectively. Besides that, the evaluation of disease-free interval (DFI) of these animals for at least 180 days after surgical excision associated with a daily low-dose treatment with Px (0.3mg/kg) and cyclophosphamide (CYC; 15mg/m2). There was no statically significant difference between COX-2 expression before and after treatment with Px; However, there was a significant decrease on Ki67 proliferative index (P<0.05). No significance was found in DFI when comparing the group treated with Px and CYC (160 days) and the control retrospective group (145 days), treated only with surgical resection. There was no statically difference on DFI when accessing histological grade, mitotic index, evolution time, lymph node metastasis, and incomplete surgical margins (P>0.05). Additionally, dogs with T4 stage, independent of the treatment, were 3.2 and 4.8-fold more likely to develop an early recurrence when comparing with T3 and T2, respectively. The results of this study demonstrate the antiproliferative effect of the Px independent of the COX-2 inhibition. The treatment with low-dose Px and CYC in association with surgery was not followed by an improvement on DFI in comparison with surgically treated animals.