Tonsillar carcinoma in dogs: Treatment outcome and potential prognostic factors in 123 cases

Abstract

Background Tonsillar carcinomas are rarely reported in dogs. Information on outcome after treatment is sparse and prognosis is guarded to poor. Hypothesis/Objectives Assess treatment outcome and potential prognostic factors in a population of dogs with cytological or histopathological diagnosis of tonsillar carcinoma. Animals A total of 123 client‐owned dogs with diagnosis of tonsillar carcinoma confirmed by cytology or histopathology. Methods Retrospective, multi‐institutional study. Medical records of 12 institutions were reviewed from 2012 to 2021. Results Treatment included surgery, chemotherapy (conventional, tyrosine kinase inhibitors or metronomic chemotherapy), radiotherapy, nonsteroidal anti‐inflammatory drugs (NSAIDs) or a combination of these. Surgery was performed in 68 cases, chemotherapy was administered in association with NSAIDs in 64 cases, NSAIDs were used alone in 14 cases and in association with surgery in 21 cases, whereas radiotherapy was used alone or in combination with surgery or chemotherapy in 20 cases. Overall survival time (OST) was 126 days (95% confidence interval [CI], 88‐164). Significantly longer survival (P < .001) was seen in dogs without evidence of metastatic disease (median survival time, 381 days; 95% CI, 116‐646). Other significant positive prognostic factors included absence of clinicals signs at presentation, surgery (tonsillectomy), use of adjuvant chemotherapy and use of NSAIDs. Conclusion and Clinical Importance Asymptomatic dogs, those treated with surgery, those that received adjuvant chemotherapy, and those that received NSAIDs may have a better prognosis than previously expected, but overall survival remains short for dogs with tonsillar carcinoma.

Metronomic chemotherapy: bridging theory to clinical application in canine and feline oncology

“…Although they are not discussed in this article given the nature of the study (case report or case series) and/or the number of animals included (less than 5), there are descriptions of the use of MC in the treatment of cutaneous angiomatosis ( 108 ), intradural-extramedullary haemangioblastoma ( 109 ), malignant Leydig cell tumour ( 110 ), malignant mesenchymoma ( 111 ), maxillofacial osteossarcoma ( 112 ), omentum myxosarcoma ( 113 ), prostatic leiomyosarcoma ( 114 ) and tonsillar carcinomas ( 115 ) in dogs and abdominal ( 116 ) and urinary bladder ( 117 ) hemangiosarcomas in cats.…”

First report of primary tonsillar salivary gland adenocarcinoma in a dog

“…[2][3][4] There is limited literature describing primary and secondary tonsillar neoplasia in dogs. 2,[5][6][7][8][9][10][11] The three most common primary canine tonsillar tumours are squamous cell carcinoma (SCC), lymphoma and malignant melanoma according to recent studies. 9,12 There are few studies reporting secondary tonsillar tumours.…”