Cutaneous epitheliotropic T-Cell Lymphoma with Multiple Metastases in a Dog Diagnosed by PCR to Antigen Receptor Rearrangement Analysis

Herein, a case of canine cutaneous epitheliotropic T cell lymphoma (CETL) with multiple organ metastases is described. An 11-year old female Yorkshire terrier presented with chronic generalized dermatitis and respiratory distress. Multiple erosive plaques and nodules in the skin, enlarged submandibular lymph nodes and tachypnea were noted at the initial presentation. Antigen receptor rearrangement (PARR) analysis by PCR revealed clonal rearrangements from the T-cell receptor gamma (TCRγ) in cells that were fine-needle aspirated from the skin and submandibular lymph node. Histopathological findings in the skin also revealed infiltration of neoplastic lymphoid cells with epithelial tropism. Furthermore, clonal rearrangement from the TCRγ was detected by PARR in the lung nodules. Based upon those findings, the present case was considered as CETL with multiple metastases, which has been only rarely reported in canine cases. In this case, diagnosis of CETL and metastases to other organs could be made by PARR analysis alone.