Case Study

11_00003 Jesse J Mast cell tumor of anus and medial iliac LN BK—NVC—

An 11-year-old FS Jack Russell Terrier dog with history of MCT – grade II on the foot in 1999 and grade I on the skin in 2004, was presented for pruritus near the base of tail. The only significant finding on physical examination was a 1.5 cm ulcerated mass in the right ventral anal mucosa. Eosinopenia and elevated MCV and MCHC were evident on CBC. The mass was surgical excised and the patient treated with antibiotics. Biopsy results showed a grade II MCT. The patient was presented three months later for recurrence of the anal mass. Abdominal ultrasound was advised prior to further surgery.

An 11-year-old FS Jack Russell Terrier dog with history of MCT – grade II on the foot in 1999 and grade I on the skin in 2004, was presented for pruritus near the base of tail. The only significant finding on physical examination was a 1.5 cm ulcerated mass in the right ventral anal mucosa. Eosinopenia and elevated MCV and MCHC were evident on CBC. The mass was surgical excised and the patient treated with antibiotics. Biopsy results showed a grade II MCT. The patient was presented three months later for recurrence of the anal mass. Abdominal ultrasound was advised prior to further surgery.

Sonographic Differential Diagnosis

Metastatic iliac lymph node presentation.

Image Interpretation

The iliac and sublumbar lymph nodes were significantly enlarged and dramatically hypoechoic the largest of which was approximately 4cm which was sampled by fine needle aspirate. Metastatic disease due to the primary anal region mast cell tumor is most likely probable.

DX

Mast cell tumor of anus and medial iliac LN

Outcome

After consultation with an oncologist, the patient was treated with palliative steroid therapy until the quality of life deteriorated and patient was humanely euthanized.