Outcomes and Clinical Features Associated with Surgically Excised Canine Salivary Gland Carcinoma: A Multi-Institutional, Retrospective, Veterinary Society of Surgical Oncology Study. Bush K1, Matz B1, Grimes J2, Linden D3, Kessler M4, Plavec T4, Rossanese M5, Chadsey L6, Bennett BB1, Coggeshall WS7. 1Auburn University, Auburn, AL; 2University of Georgia, Athens, GA; 3First Coast Veterinary Specialists, Jacksonville Beach, FL; 4Small Animal Clinic Hofheim, Hofheim am Taunus, Germany; 5Royal Veterinary College, Hatfield, United Kingdom; 6The Animal Medical Center, New York, NY; 7Smiley Data Analytics, Philadelphia, PA.
Information describing the outcomes of treatment for dogs with salivary gland neoplasia is limited but has historically been associated with median survival times (MST) of 550 days. The objectives of this study were to describe outcomes in dogs with salivary gland carcinoma treated with surgical excision and to identify prognostic factors associated with these outcomes. We hypothesized that MST would be improved compared to what has previously been reported, based on clinical experience. This was a multi-institutional, retrospective Veterinary Society of Surgical Oncology study that included dogs with surgically excised salivary carcinoma from 2000 to 2020. Seventy-two dogs met the inclusion criteria. The mandibular and sublingual glands were the most commonly affected (48.6%). The overall MST associated with salivary carcinoma was 1886 days, and dogs with lymph node metastasis at the time of surgery had a significantly shorter MST at 248 days (P < 0.001). The percentage of patients alive at one year was 81.5%, at two years was 65.1%, and at three years was 61.5%. The MST for dogs treated surgically for salivary carcinoma is improved compared to previous reports and adjunct therapy did not improve MST. The limitations of this study pertain primarily to its retrospective nature, inducing selection bias and difficulty in obtaining complete medical records. In conclusion, surgically treated salivary gland carcinoma in dogs is associated with long survival times.