Clinical staging for oropharyngeal malignancies in the dog

Abstract

One hundred dogs bearing malignancies of the oropharyngeal region were examined over a three‐year period and prospectively staged using the World Health Organisation TNM Classification of Tumours of Domestic Animals. Primary tumours were characterized by their large size or local infiltration (71 per cent, T3 status) and invasion into adjacent bone (60 per cent, Tb status). Regional lymph node metastasis was less common (17 per cent, N1b, N2b or N3 status) and distant metastasis was an unusual presenting feature (5 per cent, M1 status). The early Stage I and II tumours together accounted for 8 per cent of the total series whilst the more advanced Stage III group were by far the most frequent, representing 84 per cent. The remaining 8 per cent being classified as Stage IV because of extensive regional or distance metastatic deposits. Prognoses by stage showed actuarial survival rates at 12 months of 100 per cent for Stage I, 71 per cent for Stage II, 31 per cent for Stage III with no survivors in the Stage IV group. Survival rates for the major histological types were 44 per cent for the non‐tonsillar squamous cell carcinoma, 22 per cent for the tonsillar squamous cell carcinoma and fibrosarcomas, 17 per cent for mastocytomas whilst none of the malignant melanomata survived 12 months.

The surgical management of bone‐involved oral tumours in the dog

“…Whilst this study was not conducted on the basis of a prospectively randomized trial one can compare the actuarial survival rates achieved here with those reported elsewhere for similar groups of oral tumours. The survival rate in this study for the squamous cell carcinomas of 80 per cent bears very favourable comparison with that reported for a similar group of mainly stage I11 squamous cell carcinomas of 44 per cent (White et al, 1985). Data for survival rates of oesteosarcoma of the oral cavity are not available and a direct comparison cannot therefore be made.…”

“…Oral tumours in the dog are frequently complicated by the presence of neoplastic cells in bone (White, Jefferies & Freedman, 1985). For anatomical reasons it has often been considered impractical to excise radically these tumours and treatment had tended to rely on modalities which are suited to the management of the tumour in situ; including radiotherapy, cryosurgery or 'debulking' surgery and their various combinations.…”

Canine tonsillar squamous cell carcinoma - a multi-centre retrospective review of 44 clinical cases

“…Previous case series have described an improved outcome in dogs receiving radiotherapy for TSCC (MacMillan and others 1982, White and others 1985, Brooks and others 1988, Murphy and others 2006) although results have not necessarily been substantiated statistically by comparison to untreated controls. The small number of animals and the variety in treatment protocols make it difficult to assess the benefit of radiotherapy in this cohort of animals.…”

“…Canine tonsillar squamous cell carcinoma (TSCC) is an uncommon disease, representing 9% of canine oral tumours in a UK survey (Bostock and Curtis 1984), and there is relatively limited information regarding presentation, treatment and outcome in the current literature. In contrast to non‐tonsillar SCC, TSCC is characterised by rapid growth, infiltration of underlying tissues and high metastatic potential (Brodey 1970, Todoroff and Brodey 1979, White and others 1985), and is generally regarded to carry a poor prognosis (Brodey 1970, MacMillan and others 1982, Brooks and others 1988).…”

Rib metastases from a non‐tonsillar squamous cell carcinoma in a dog

“…The biological behaviour of non‐tonsillar SCC and its low metastatic rate generally make surgical resection with wide margins an effective treatment for prolonging survival times and preventing local recurrence (White 1991). The prognosis for non‐tonsillar SCC is strongly correlated to tumour stage, degree of local infiltration, bone involvement and regional and distant metastases, as determined by the World Health Organisation TNM Classification of Tumours of Domestic Animals (White and others 1985). The location of the primary lesion within the oral cavity also determines the efficacy of surgery in achieving complete excision and prevention of local recurrence (Schwarz and others 1991).…”