Liver Tumors: Diagnosis and Treatment

Introduction

Primary liver neoplasms are infrequent in the dog and cat, with an estimated prevalence in necropsy studies of 0.6-2.6% in canines and 1.5-2.3% in felines. In the dog liver metastases are much more frequent than primary hepatic tumors, and affect 30.6-36.8% of all animals with non-hepatic neoplasms, the spleen, pancreas and gastro-intestinal tract being the most common primary tumor locations implicated in such metastases. In cats it is estimated that 20% of all liver tumors are metastases of primary malignancies located in the pancreas, gastrointestinal tract or kidneys (1,2,3,4,5). [...]

Key Points

• Primary hepatobiliary neoplasms are rare in the dog and cat, and tend to affect older animals which present with non-specific or gastrointestinal clinical signs.
• The clinico-morphological presentation of the disease, its cellular origin and its nature (benign or malignant) usually determine the therapeutic options and prognosis.
• The clinical approach to such cases involves multiple laboratory tests including urine and coagulation analysis, survey radiographs and abdominal ultrasound, as well as liver cytology or biopsy.
• Surgery only offers a good prognosis in the case of lobar presentations or benign neoplasms. Chemotherapy is usually ineffective for primary liver tumors.
• Most animals with malignant lesions tend to have metastases or diffuse disease presentations at the time of diagnosis, with a correspondingly poor prognosis.