Evaluation of lung lobectomy and adjuvant treatment for primary pulmonary carcinoma in dogs: 89 cases (2005-2022).

Abstract

OBJECTIVES: Primary lung cancer is relatively common in dogs. Despite the existing literature on long-term follow-up and outcome, further clinical studies focusing on a single histotype are needed, specifically about epithelial tumours since they are the ones most frequently detected. MATERIALS AND METHODS: The medical records of four European institutions were reviewed to identify dogs undergoing lung lobectomy for a primary lung carcinoma between 2005 and 2022. RESULTS: A total of 89 dogs were included. Median age was 11&#x2009;years (range 5 to 17&#x2009;years) and median body weight was 23&#x2009;kg (range 2.5 to 47&#x2009;kg). Overall median survival time was 252&#x2009;days (range 6 to 1558&#x2009;days) and overall progression-free interval was 140&#x2009;days (range 7 to 684&#x2009;days). The 1-, 2- and 3-year survival rates were 61%, 47% and 30%, respectively. Presence of clinical signs at presentation, pleural effusion, completeness of surgical margins, histopathological features and use of adjuvant chemotherapy did not influence survival. Patients with maximum tumour diameter &#x2265; 5&#x2009;cm had a reduced survival compared to patients with smaller tumours (median survival time 284&#x2009;days vs. 717&#x2009;days, 95% CI 8 to 719), and dogs with histologically confirmed lymph node metastasis had a reduced survival compared to patients with no evidence of local metastasis (median survival time 162&#x2009;days vs. 614&#x2009;days, 95% CI 39 to 760). None of the other assessed variables influenced progression-free interval. CLINICAL SIGNIFICANCE: Dogs with primary pulmonary carcinoma with no lymph node involvement and with a maximum tumour diameter of < 5&#x2009;cm may have a better prognosis and prolonged survival. Further studies are needed to elucidate the role of adjuvant chemotherapy in case of clinically aggressive lung cancer.