ORAL TUMOURS – Mandibulectomy, Maxillectomy

There are various areas that a tumor can arise from in the oral cavity, this includes the bone, soft tissue structures in the mandible and maxilla jaw, teeth, tongue, or pharynx. Most oral cavity tumors are malignant. The most common tumor in cat is the squamous cell carcinoma and in dogs it is the squamous cell carcinoma and the malignant melanoma. The following are other malignant oral tumors: osteosarcoma, fibrosarcoma, mast cell and multilobular osteochondrosarcoma.

It is also common for your pet to develop benign oral tumors, these include peripheral odontogenic fibroma and acanthomatous ameloblastoma. It is usually recommended that benign and malignant tumors are treated surgically, however there are usually other options available. These options are dependent on the type of tumor and include chemotherapy, radiation therapy and immunotherapy. These options may be used in addition to or instead of surgery for some tumors.

Oral tumors are generally common in both dogs and cats, Tumors of the oral cavity make uop 6% of tumors in dogs and 3-12% of tumors in cats.

There are a few visible signs that indicate your pet may have an oral tumor, including:

• face swelling or eye bulging;
• mass located in the oral cavity;
• nasal discharge containing blood;
• bloody saliva, increased salivation and odorous breath;
• struggle with eating, difficulty opening mouth and weight loss.

If teeth become loose, especially if the animal generally has good teeth, it may indicate that cancer is causing bone loss.

If it is suspected that your pet has an oral tumor there are various examinations and tests that should be done. These include physical examination, radiographs or CT scans for the skull and chest, blood tests and aspiration of regional draining lymph nodes. These tests are recommended as they help evaluate the chance of metastasis and provide a clear image of the pet’s health.

Options for treatment are dependent on where the tumor is located and the type of tumor it is. The margin of excision is 1cm for benign tumors and 2-3cm for malignant tumors.

A part of the lower jaw is removed in a mandibulectomy. There are different type of mandibulectomy procedures which depend on the amount of jaw that needs removal. Less aggressive techniques can be used for low-grade malignant and benign tumors. If the tumors are malignant or large, the procedure may need to be more aggressive, such as a total or subtotal hemimandibulectomy.

The removal of a portion of the upper jaw is known as a maxillectomy. Again, there are various procedures that can be done, for example, some of the procedures may include orbit, mandible, skull or nose removal. It also depends on location, size and type of tumor.

Animals are generally discharged 2-5 days after the procedure. This depends on the level of surgery, ability to eat and comfort. They should be returned for a check-up 10-14 days after surgery. The owner will receive a prescription for pain killers which can be administered at home.

There are a few restrictions which should be followed after surgery, these include:

• make use of a restrictive collar up to 14 days after surgery to prevent your pet from getting to the surgical site;
• limited activity for 14 days after surgery;
• soft foods for 2-3 weeks after operation, in some cases a feeding tube may be necessary;
• restriction of chew toys, ball playing and raw hide for 2-4 weeks after operation.

There are a few complications to look out for after surgery. These include, incision breakdown, increased salivation, nose bleeding, swelling beneath the tongue, difficulty with eating, tumour recurrence and mandibular drift (lower jaws do not line up properly)

The prognosis for your pet is dependent on type, location, size, surgery success and metastatic disease presence. Sometimes further therapy should be used to prevent metastasis and recurrence.