Ultrasound‐Guided Cytology of Spleen and Liver: A Prognostic Tool in Canine Cutaneous Mast Cell Tumor

Abstract

Background: In the clinical staging of cutaneous mast cell tumors (cMCT), the diagnosis of metastasis is controversial based on cytological examination of lymph nodes, spleen, liver, bone marrow, and blood.Objectives: To define the prognostic role of ultrasound-guided cytology of spleen and liver in cMCT. The results of cytological evaluation were compared in relation with survival time.Animals: Fifty-two client-owned dogs with a diagnosis of cMCT. Methods: Selection of cases was based on cytological evaluation of liver and spleen to detect infiltration at distant sites. The Kaplan Meier method was used to compare survival in dogs with and without infiltration of spleen and liver (log-rank test P o .05).Results: Ten dogs with cMCT had mast cell infiltration of spleen, liver, or both and 4 of these dogs had involvement of the regional lymph nodes. The majority of dogs had 2 or more ultrasonographically abnormal findings simultaneously in spleen and liver. Nine dogs had grade II cMCT, and 1 had grade III cMCT. Dogs with positive evidence of mast cell infiltration to spleen, liver, or both had shorter survival times (34 versus 733 days) compared with dogs negative for mast cell infiltration at distant sites.Conclusion and Clinical Importance: Dogs with evidence of mast cell infiltration at distant sites have a shorter survival times than dogs without evidence of infiltration at distant sites. This study suggests that cytology of spleen and liver is indicated either for ultrasonographically normal or for ultrasonographically abnormal spleen and liver in dogs with cMCT.

Concordance of c‐kit Mutational Status in Matched Primary and Metastatic Cutaneous Canine Mast Cell Tumors at Baseline

“…Initial staging included history and physical examination, complete blood cell count with differential, serum biochemistry, coagulation profile, cytological evaluation of the cutaneous nodule and regional lymph node, thoracic radiographs (3 views), abdominal ultrasound, fine‐needle aspirates of liver and spleen regardless of their sonographic appearance, and cytologic examination of bone marrow obtained from the iliac crest. Lymph nodes or viscera were considered metastatic, if mast cells appeared in clusters or sheets, in very large numbers or atypical on morphology, as previously documented 18. Histologically, nodal metastatic spread was supported by the localization of mast cells in the subcapsular sinuses; special histochemical stains (Giemsa) were used to detect poorly granulated mast cells.…”

Canine mast cell tumours: decision‐making and treatment

“…Where evidence of higher grade tumours exists, or there is evidence of MCT metastasis to the local lymph node, further staging to include abdominal ultrasound and possibly FNA of the liver and spleen is indicated. The latter is yet another debatable subject within veterinary oncology; some suggest that aspiration of even ultrasonographically normal livers and spleens should be performed owing to a poorer prognosis in dogs with mast cells detected at these sites (Stefanello and others 2009), while other studies have shown no value to aspirating normal appearing visceral organs (Finora and others 2006). The authors' approach is to aspirate the liver and/or spleen only where ultrasonographic changes are present or the tumour is considered high risk, with nodal metastasis detected.…”

Liver

“…Primary hepatic neoplasias are hepatocellular adenoma and carcinoma; bile duct adenoma (cystadenoma) and carcinoma Continued such as nodular hyperplasia, pyogranulomatous hepatitis, chronic active hepatitis, and cirrhosis may also produce target lesions. [100][101][102] The liver may appear normal because there is an inherent difficulty in detecting mild changes in hepatic size and echogenicity. Hepatic lymphosarcomas have a variety of ultrasound appearances.…”