Renal Lymphosarcoma in Dogs

Animals suffering from this condition often display vague symptoms such as anorexia and lethargy, if your pet is displaying behavior not typical of him it is vital that veterinarian consultation is sought quickly. These generalized signs are often the first symptoms for underlying conditions that may progress rapidly without prompt treatment.

Lymphoma is a commonly reported neoplasia in dogs, with 0.1% of susceptible dogs presenting with this disorder. Renal lymphosarcoma is a rare form of this condition and is often highly invasive, quickly metastasizing to other regions of the body such as the lymph nodes and lungs.

The symptoms of renal lymphosarcoma are often non-specific to the condition including:

• Nausea
• Anorexia
• Weight loss
• Lethargy
• Blood in the urine 

Depending on the disease progression, signs of chronic renal failure may also be seen. These include:

• Increased thirst and urination
• Vomiting and diarrhea

With large tumors, hind limb swelling may be caused by pressure put on the vena cava. Parathormone release from the tumor may cause hypercalcemia.

Canine lymphoma is a disease name that covers a group of malignancies that occur following the uncontrolled expansion of B or T-cell immunophenotype lymphoid cells. The lymphoma can vary in aggression, although often will quickly go on to affect the primary and secondary lymphoid tissues. These tissues affected include the thymus, spleen and lymph nodes. There are a number of renal tumors that occur in dogs, unfortunately these tumors are often cancerous. These cancers include: 

• Renal cell carcinoma
• Transitional cell carcinoma
• Anaplastic carcinoma
• Lymphoma
• Hemangiosarcoma
• Anaplastic sarcoma
• Nephroblastoma 

Although rare, benign tumors can occur within the kidneys such as papillomas or fibromas.

Your veterinarian will perform a full clinical examination on your pet. Often your pet will present with vague signs of illness such as anorexia and weight loss. Your veterinarian will palpate your dog’s abdomen; in some cases of the disease they will be able to feel the kidneys due to abnormal enlargement.  

If your veterinarian suggests this condition, she may perform radiographs of the abdomen. Your pet may require sedation for these to be carried out. Your canine’s kidney may be seen as an irregular size or shape, a mass may be visible, or signs of calcification seen. In some cases, enlargement may cause visual displacement of the small intestine. Your veterinarian may go on to perform radiographs of other locations, including the chest, to check for further metastases of the disease.

Ultrasonography may also be utilized which would show the veterinarian the size, shape and condition of the kidney, this may also show renal calcification. Ultrasonography can be used as a tool to perform a guided fine needle aspiration if the kidney is not easily palpated on examination. This sample will allow cytology which can identify the tumor type.

Your veterinarian will perform further investigations such as: 

• Biochemistry – which may show an elevated level of urea and creatinine in cases where renal failure has begun to occur
• Urinalysis – which may show protein in the urine due to decreased ability of the kidneys to metabolize the molecule and hematuria

The treatment of the disease will vary depending on the stage of the disease on diagnosis. 

Surgery 

If further tissues have not been affected and the tumor is contained within the kidney, surgical removal of the kidney may be considered. Your pet will require a general anesthetic and although there are risks involved with this he will be carefully monitored throughout the surgery. 

Chemotherapy 

Chemotherapy may be considered for your pet. This treatment is known to be highly effective for a range of canine lymphoma disorders when aggressive protocols are used. The treatment plan will be individualized for your dog by your veterinarian and may involve short, dose intense protocols.

The prognosis for your pet varies depending on stage of the disease upon diagnosis. In cases where complete tumor removal is possible and chemotherapy is received, the prognosis may be good for your pet. Unfortunately, in cases where metastases have occurred or surgical removal is not possible due invasion of the vena cava, adrenal glands, or spinal muscles, prognosis may be poor. 

If your pet requires surgery it is vital to provide him with a warm, quiet environment for recovery. The surgical site should be carefully monitored during healing and self-trauma prevented.

Highly palatable food should be given to encourage nutrition, and energy for healing. To support the immune system during chemotherapy a complete, balanced with added antioxidants should be given. Discuss whether a therapeutic kidney diet will be beneficial for your pet’s recovery with your veterinarian. As dehydration can occur in renal conditions encourage fluid intake and provide canned food with high water content.