# Papillary Renal Cell Carcinoma With Widespread Metastases in an Arabian Mare

## TL;DR

An Arabian mare was found to have a large kidney cancer with metastases, presenting as colic, highlighting the need to consider cancer in abdominal pain cases.

## Contribution

This case report documents papillary renal cell carcinoma with metastases in a horse, emphasizing colic as a possible symptom of abdominal tumors.

## Key findings

- A 23-kg papillary renal cell carcinoma was found in the mare's left kidney.
- The tumor had metastasized to the liver, diaphragm, and lungs.
- Colic was identified as a potential symptom of intra-abdominal neoplastic lesions in horses.

## Abstract

This report describes a case of massive renal cell carcinoma (RCC) causing mild chronic colic in a 20‐day‐postpartum Arabian mare. The mare presented with deteriorating abdominal pain following normal parturition. Clinical examination revealed tachycardia, tachypnoea, weak intestinal motility and pale mucosal membranes. Rectal examination identified a very large mass in the caudal part of the abdominal cavity, and abdominal ultrasound examination revealed a huge space‐occupying mass with renal architecture. During midline exploratory laparotomy, a massive tumour was observed in the anatomical location of the left kidney, with numerous adhesions to abdominal organs. Due to the severity of the condition and intra‐abdominal spread of the neoplasm, the horse was euthanized intraoperatively. Upon necropsy, a 23‐kg mass was found in the left kidney, along with widespread metastases to the liver, diaphragm and lungs. Histopathological examination confirmed primary and metastatic papillary RCC. This case highlights that colic should be considered a potential symptom of neoplastic lesions within the abdomen.

An 8‐year‐old Arabian mare presented with mild abdominal pain and weight loss. A huge papillary renal cell carcinoma with widespread metastases was identified via exploratory laparotomy, followed by histopathologic examination. Colic must be considered as one of the symptoms of intra‐abdominal neoplastic lesions.