GI Proliferative / Neoplastic Disease Flashcards
Categories of proliferative lesions
Infectious or idiopathic inflammory
Non-malignant “benign”
Malignant neoplastic
Common clinical signs of proliferative lesions of the oral cavity
Pain —> dysphagia or anorexia
Difficulty prehending or masticating food
Swelling
Ulceration/bleeding
Halitosis
Hypersalivation
Eosinophilic granulomas
Common in cats, arctic dog breeds
Gross lesions: ulcerated solitary masses, plaques (oropharynx, lips)
Histo lesions: eosinophilic granulomatous inflammation with flame figures (hyalinzed, hyper eosinophilic collagen)
Chronic lymphocytic plasmacytic-gingivitis-stomatitis complex
Cats
Gross: raised, thickened, hyperemia plaques (gingiva, buccal mucosa) —> secondary erosions/ulcers; severe submucosal lymphoplasmacytic infiltrates —> erosions/ulcers
Papular stomatitis
Camlids, ruminants
Cause: parapoxviruses ZOONOTIC (ORF, bovine papular stomatitis)
Pathogenesis: epithelial cell infection —> virus induced hyperplasia/dysplasia —> epithelial degeneration —> inflammation —> pustules, ulcers, crusts
Papillomas
Benign neoplasm (DDx papular stomatitis)
Cause: viral, congenital, idiopathic
Lesions: hyperplastic and dysplastic stratified squamous epithelium (+/- viral inclusion), exophytic (flat or pedunculated), verrucous masses
May regress spontaneously, excellent prognosis
Fibrogingival hyperplasia
Benign proliferative (older dogs, esp Boxers)
Associated with chronic gingivitis/periodontal dz
Ddx: peripheral odontogenic fibroma
Gross: firm lesions
Histo: hyperplastic mucosa, proliferative fibrovascular tissue
Prognosis: good, but difficult to resolve
Epulis (Epulides pl) or Peripheral odontogenic fibroma (POF)
Neoplasm of periodontal ligament origin - benign
Older dogs (esp Boxers, some cat)
Gross: larger/firmer (firm to hard) than papilloma, pedunculated or sessile
Histo: islands of odontogenic epithelium (epith. rests of Malassez), periodontal-ligament like stroma
Prognosis: great - surgical excision cures, may recur
Acanthomatous ameloblastoma
Locally aggressive neoplasm, infiltrates bone —> local tissue destruction; no metastasis; post-surgical recurrence common
Gross: resemble FGH or POF
Histo: cords and sheets of neoplastic ameloblasts +/- osseous/dentinous elements
Oral melanoma
Most common canine oral malignancy ~40% of oral tumors in dogs; less common in cats
Local tissue destruction, rapid metastasis
Histo: excess melanocytes
Prognosis: guarded/poor
Oral Squamous cell carcinoma
Cats - sublingual mucosa, Dogs - tonsils and gingiva
Less common in horses/cattle
Gross: large ulcerated masses, surface necrosis/ulceration, highly infiltrative (destroy local tissue/bone)
Histo: exophytic or endophytic, cords of atypical sq epith —> desmosomes —> keratin pearls; high mitotic index
Prognosis: poor - Locally invasive, aggressive; Metastasis to region lymph nodes
Alimentary lymphoma/lymphosarcoma
Solid tumors and diffuse infiltrative forms
Cats: most common GI neoplasm
Dog: equal frequency with intestinal carcinoma
Cow: abomasal LSA most common GI neoplasm (+/-BLV)
Horse: most common intestinal neoplasm
Pathogenesis of infiltrative disease
Cell infiltrate —> dilated lacteals —> protein/lipid loss
Histo of intestinal LSA
Diffuse infiltration of neoplastic round cells (scant cytoplasm, large round nucleus, high N:C ratio)
Adenocarcinoma
Dog: most common GI neoplasia
Cat: second most common GI neoplasia
Invasive neoplasm with desmoplasia - firm white lesions, “napkin ring” stenosis lesions
Clinical signs by location: ulcer/vomiting/anorexia, constipation/straining/pain on dedication/hematochezia
Carcinomatosis common
Poor prognosis
