Tumors of the jaw in cats, diagnosis and treatment

Types of tumors and signs of the disease

Malignant tumors of the jaw in cats account for 3–8% of all tumors.
The average age of incidence is 11-12 years, but in practice there are cases of oral cavity tumors in younger individuals (4-5 years). Tumors of the oral cavity include all neoplasms that are localized in the mucous membrane of the gums and oral cavity, tongue, sublingual region and tonsils. Tumors of the mucous membranes tend to invade the underlying bone, so the diagnosis is often made of a tumor of the upper/lower jaw.

Symptoms of a mouth tumor in a cat

drooling (sometimes with blood);
refusal of food;
difficulty eating food;
weight loss;
unpleasant odor from the mouth;
an increase in the volume of tissues of the upper or lower jaw;
nose bleed;
loss of teeth;
bloody discharge from the eye;
blocking of the temporomandibular joint.

Among all malignant tumors of the oral cavity in cats, squamous cell carcinoma occurs with a frequency of 74%, fibrosarcoma - 20%, others - 6%.

Tumors of the oral cavity in cats rarely metastasize to the lungs and are more local invasive (destruction of the bones of the upper or lower jaw, orbit of the eye, increased volume of soft tissue, impaired tongue function), as a result of which the animal refuses to eat food.

Malignant neoplasms in the oral cavity in dogs and cats

Oral cavity tumors are the most common malignant neoplasms in veterinary practice. In cats they account for 3-10% of all cancers; in dogs, in terms of frequency of detection, they are in 4th place among all tumors. The most common cancers in dogs are malignant melanoma (MM), squamous cell carcinoma (SCC) and fibrosarcoma (FSA). In cats, PCK predominates, FSA is less common. The prognosis for the outcome of the disease depends on the type and size of the tumor, as well as its location. For benign tumors or inflammatory processes in the cavity or mouth (viral papillomas, epulid tumors, eosinophilic granulomatosis), the prognosis for the outcome of the disease is favorable. These neoplasms must be differentiated from malignancies when evaluating patients with oral neoplasia.

This publication describes the most common types of oral malignancies in cats and dogs, as well as the latest treatments and clinical trial results.

Clinical symptoms Clinical signs of neoplasms in the oral cavity are nonspecific and depend little on the specific type of tumor. Tumors located rostrally in the animal's oral cavity are easy to detect, and pet owners who discover foreign tissue mass in their pet contact their veterinarians (Figure 1). Neoplasms of such localization are easier to diagnose in the early stages of development and promptly and completely remove. Accordingly, the prognosis for the outcome of the disease in such cases is more favorable, especially for some types of tumors, for example, PCI in dogs. Neoplasms located deep in the oral cavity are not always recognized in time. They can be difficult to detect visually, and pet owners often mistake them for benign tumors. Meanwhile, a suspicion of the presence of a cancerous tumor in the oral cavity can be noticed during routine procedures, for example, brushing the animal’s teeth. Such a sign in a dog or cat is the presence of loose teeth in the general good condition of the dental system. When extracting similar teeth from a cat or dog, it is necessary to urgently conduct a biopsy and histological examination of gum tissue samples. This is of great importance for the early detection of PCI in cats.

Figure 1. Oral squamous cell carcinoma in a dog, located rostrally.

The presence of a tumor in the animal's oral cavity is indicated by ptyalism (increased salivation, Figure 2), halitosis, difficulty swallowing, weight loss or loss of appetite, as well as enlargement and hardening of the mandibular and peripharyngeal lymph nodes, revealed by palpation, loss of interest in chewing toys, the appearance of blood stains on pieces of food, in drinking water and on bedding. Other signs are exophthalmos, asymmetry of the muzzle, sneezing, nasal discharge, scratching the mouth with the paws. The veterinarian should always examine the animal’s oral cavity during any general clinical examination, but it is especially important to carefully examine it if the animals have the above signs

Figure 2. Excessive salivation is one of the symptoms of neoplasms in the oral cavity in animals

Diagnostic examination

Diagnostic methods and techniques for tumors in the oral cavity are determined by the location of the tumor. Tumors located rostrally in the oral cavity are easily accessible, and tissue samples can be obtained after sedating the animal. However, tumors located deep are difficult to access and often bleed after biopsy. To perform a biopsy in such cases, general anesthesia is indicated. Before anesthesia, you need to carefully examine the patient and do general clinical and biochemical blood and urine tests. If a malignant tumor is suspected, a three-plane chest x-ray is recommended, which helps identify metastases. Although it has been shown that metastases are rarely detected in dogs at the time of initial detection of a tumor in the oral cavity (approximately 13.6% of cases), their presence is a contraindication to surgical intervention. X-rays (Figure 3) or computed tomography of the affected areas help to assess the size of the tumor and, depending on this, determine how to treat it. Approximately 60-80% of neoplasms in the oral cavity are localized on or near the gums and penetrate into the bone tissue of the jaws, destroying it, which is clearly visible on x-rays. If an oral malignancy is suspected, it is recommended that the animal undergo oral radiographs and a biopsy under general anesthesia to avoid overexposing the animal to anesthetic agents. Visual examination does not always accurately assess the extent of tumor spread, especially in cases of PCI in cats.

Figure 3. To assess the extent of the tumor and plan its treatment, it is recommended to conduct radiography or computed tomography of the tumor area (for example, a tumor of the lower jaw)

To differentiate malignant neoplasms in the oral cavity from benign tumors and inflammatory processes that are similar in appearance, a biopsy is necessary. The study looked at cats with tumors on the lower jaw, and in 50% of the animals the tumors were benign or the result of inflammatory processes. If the tumor is small and located superficially, the biopsy can be carried out in a gentle manner and be of a therapeutic nature (Figure 4). However, with a large, deeply penetrating tumor, the biopsy must capture the tumor tissue to its entire depth - only this approach will allow a correct assessment of the scope of the upcoming surgical intervention and ensure complete removal of the tumor, since the type of tumor and the stage of its development largely determine the tactics of the operation and the course of subsequent treatment. Such a biopsy should be extensive in order to best reflect the histological structure of the tumor. When performing a biopsy, necrotic areas adjacent to the tumor should be avoided. You should also not limit yourself to a superficial biopsy. When performing a surgical biopsy, the sampling site must be chosen so that it is clearly visible during subsequent surgery. If the tumor is located in the oral cavity, tissue samples are best obtained through the oral cavity - there is no risk of “contamination” of tumor cells in surrounding tissues (which may require histological examination later). Electrocoagulation to stop bleeding should be used after a biopsy, as it can disrupt the original histological structure of the tissue.

Figure 4. For small tumors, it is convenient to perform an excisional biopsy while simultaneously removing the accessible part of the tumor

Figure 5. Malignant oral melanoma in dogs metastasizes rapidly. In this dog, 2 months after the initial detection of MM, numerous metastases are visible in the abdominal area

Figure 6. Squamous cell carcinoma is the most common oral malignancy in cats. The tumor is usually located on the gums or under the tongue.

Biopsy samples must be examined by a qualified veterinarian in a laboratory equipped with a set of methods for immunohistochemical analysis. The cells of some types of oral tumors are poorly differentiated and may require special tissue staining techniques to identify them. For example, to detect carcinoma cells, staining for the presence of cytokeratin is required, to detect sarcomas - for the presence of vimentin, and to diagnose melanomas - staining for the presence of protein S-100, melanin A and neuron-specific enolase. Melanomas are especially difficult to differentiate - their cells are diverse in shape and can be round (like lymphoma and plasmacytoma cells), oval (like carcinoma cells) or elongated, spindle-like (like sarcoma cells). In addition, sometimes melanoma cells do not contain melanin granules, which are usually their characteristic feature detected during pathological examination. The most informative is not only histological, but also cytological examination of tumor tissue with subsequent comparison of the results obtained. When conducting such a comparative analysis, before fixing the biopsy samples with formaldehyde, smears of these samples should be made on glass slides for cytological examination.

It is very important to conduct a histological analysis of the lymph nodes adjacent to the tumor (especially those located on the same side). Samples of their tissue should definitely be obtained by biopsy, even in cases where they are not enlarged or compacted. It is difficult to assess the presence of metastases of regional lymph nodes only with the help of palpation and examination. In one clinical study, 44 dogs and cats with cancer were examined (in 9 animals the tumors were localized in the oral cavity). It was found that upon palpation of regional lymph nodes, metastases were detected only in 60% of cases, and the specificity of diagnosis was 72%. At the same time, when studying the condition of the lymph nodes using aspiration biopsy, metastases were detected in 100% of cases, and the specificity of diagnosis was 96%. If, upon palpation of regional lymph nodes or as a result of cytological examination, there is a suspicion of the presence of metastases in them, it would be reasonable to remove these lymph nodes.

Currently, there is no data that would indicate an acceleration of tumor metastasis after removal of regional lymph nodes. There is also no data indicating the possibility of metastasis to lymph nodes that were not detected histologically. It should also be remembered that the outflow of lymph from the tissues of the oral cavity also partially occurs through the parotid and medial retropharyngeal lymph nodes. Since they cannot be palpated, when examining an animal, in addition to radiographs of the tumor itself, it is necessary to obtain a radiographic image of them. If there are metastases in the lymph nodes, treatment aimed at removing only the primary tumor will not be effective.

Biological features of oral tumors

Malignant melanoma

Malignant melanoma (MM) is the most common type of oral tumor in dogs and is less common in cats. The incidence of melanoma in males and females is approximately the same. The average age of animals in which melanoma was first diagnosed is 11 years. Melanoma is a malignant tumor and in 80% of cases gives local and distant metastases (Figure 5). In the presence of small tumors (up to 2 cm) that have not given metastases (stage I of development), the prognosis for the outcome of the disease is more favorable than in the presence of large tumors (over 4 cm) or tumors that actively metastasize to regional lymph nodes (stage III of development) According to one research, the average lifespan of dogs with stage I CM was 511 days, and stage III CM was only 164 days. Some studies have noted that melanomas located in the posterior parts of the upper jaw or anterior parts of the lower jaw have a less malignant development than MM localized in other parts of the oral cavity, and therefore the prognosis for the outcome of the disease is more favorable. Other studies, however, do not confirm the relationship between the location of the tumor and the prognosis of disease outcome. Squamous cell carcinoma (SCC)

This tumor ranks first in frequency of detection in the oral cavity in cats and second in dogs. CC is a local but deeply penetrating cancerous tumor. Very often it grows into the bone tissue and causes its lysis, therefore, when diagnosing, you should pay special attention to the degree of destruction of bone tissue and the depth of tumor penetration. CC most often occurs in dogs and cats of the older age group (the average age of initial diagnosis is 8.8 years in dogs and 10.5 years in cats). It is believed that possible causes of FCC in cats are the presence of animals in smoky rooms and the use of anti-flea drugs containing substances with carcinogenic properties. Due to the habit of cats to lick and clean their fur, carcinogenic compounds enter the animal's oral cavity and initiate the development of CC. The most common site for CC in cats is under the tongue and in the gum area (Figure 6).

Squamous cell carcinoma on the tongue of a dog

Unlike LM, PCK rarely metastasizes to regional lymph nodes. The exception is tumors located on the tonsils and tongue. With such a localization of the tumor in dogs (Figure 7 and the prognosis for the outcome of the disease is unfavorable. Sometimes an increase in regional lymph nodes with PCK localized on the tonsils is a reason for the animal owner to contact a veterinarian. Often in such cases the tumor itself appears later.

The prognosis for the outcome of PCI in dogs largely depends on the location of the tumor. At the same time, in places of usual localization, PCI can be successfully treated with surgery or radiation therapy. However, tumors localized on the tonsils or at the root of the tongue are difficult to treat, recur and quickly metastasize. Often in dogs, CC develops on both tonsils at once. In such cases, the animal usually does not survive more than a year. The prognosis for the outcome of the disease is also unfavorable for cats - only 10% of animals with PCI live more than a year even after treatment.

Fibrosarcoma

Fibrosarcomas (FSAs) are malignant tumors that develop from connective tissue. In the oral cavity of cats and dogs, they most often occur on the gums. In dogs, FSAs are usually located at the base of the maxillary carnassial teeth. Sometimes fast-acting forms of FSA in dogs develop from the tissues of the hard and soft palate on the upper jaw. FSA, compared with CC and melanomas, affects dogs at any age (the average age of affected animals is 7.6 years). The age range for the initial detection of this tumor is quite long - 0.5-15 years. FSA quickly grows into the underlying bone and surrounding tissue, which makes it difficult to determine the boundaries of its spread. In some cases, based on the results of histological analysis, the tumor is determined to be benign or slightly malignant, but it grows extremely quickly. Most often, the disease occurs in this way in dogs of the Golden Retriever breed, if the FSA is localized on the upper or lower jaw (Figure 9). The overall rate of metastasis of the FSA is less than 25%. In this case, metastases usually develop in regional lymph nodes or in the lungs.

Figure 8. Squamous cell carcinoma on the tonsils of a dog.

Figure 9. Fibrosarcomas of the lower jaw in dogs of the Golden Retriever breed can be determined as benign according to histological examination, but they grow very quickly

Figure 10. Because squamous cell carcinomas rarely metastasize, local surgery (eg, rostral mandibulectomy) is effective.

Figure 11. Large inoperable tumors (eg, melanoma) involving the middle part of the hard palate can be palliated with intermittent high-dose x-rays.

Osteosarcoma

In dogs, approximately half of axial osteosarcomas (OS) are located in the maxilla or mandible. The prognosis of the outcome of the disease depends on the location of the tumor. OS located in the lower jaw has a more favorable prognosis for the outcome of the disease compared to OS localized in the upper jaw. According to research results, the average life expectancy of dogs after surgical removal of OS of the upper jaw did not exceed 5 months, while in the case of OS of the lower jaw, approximately 70% of animals lived for at least a year. When the tumor is localized in the lower jaw, surgical intervention is sufficient to achieve a positive effect; for other localizations of the tumor, in addition to surgical removal, chemotherapy is also necessary.

Treatment of malignant tumors of the oral cavity

The main methods of treating malignant neoplasms in the oral cavity in dogs and cats are surgical removal of the tumor, radiation therapy and chemotherapy with antitumor drugs. Less commonly used are immunotherapy, photodynamic therapy, and hyperthermia treatment.

Surgical removal of the tumor

Complete surgical removal of the tumor is the most radical and effective method of treating malignant neoplasms of the oral cavity. Rostral tumors, including tongue tumors, should be removed during surgery depending on the extent of the tumor tissue (Figure 10). One review analyzed 81 cases of malignant tumors of the mandible in dogs that were removed surgically by mandibulectomy. The lifespan of animals after surgery largely depended on the location of the tumor. With neoplasia localized in the anterior, middle and posterior parts of the lower jaw, the average survival time of dogs was 64, 9 and 20 months, respectively.

Dogs retain the ability to eat and drink even after half of the mobile part of the tongue is removed. Cats do not tolerate such surgical intervention well, due to the suppression of the ability to groom, their coat condition significantly deteriorates. The average lifespan of 80% of dogs undergoing mandibulectomy for a mandibular cervical ligament is more than 1 year. After surgical removal of the same tumor located on the tongue, only 25% of animals survive to a year. The prognosis for the outcome of the disease is even more unfavorable for cats suffering from PCI; animals who have undergone mandibulectomy live 2.5 to 6 months after surgery. In both cats and dogs with oral cancer, insertion of a gastrostomy tube for nutritional support may be a palliative treatment option. Seven cats following mandibulectomy and regional lymph node resection were given nutritional support through a feeding tube while receiving postoperative radiotherapy. At the same time, the average life expectancy of animals after surgery was 14 months.

The boundaries of the tissue to be removed when performing surgical excision of tumors on the lower or upper jaw should be at least 2 cm from the visible boundaries of the tumor. Despite this, sometimes a complete maxillectomy or mandibulectomy is not necessary. One study found that the effectiveness of surgical removal of oral ulcers in dogs depends little on the radicality of the operation. With partial mandibulectomy, 91% of dogs with PCK, 50% of animals with FSA, and 21% of animals with ZM lived for 1 year. 85% of pet owners were satisfied with the outcome of partial mandibulectomy performed on 27 dogs with oral tumors. Pet owners noted that after surgery their dogs had no pain.

For small tumors (less than 2 cm) that do not penetrate deep into the bone tissue, cryosurgery gives good results. However, when larger tumors are removed by cryosurgery, severe complications often develop in the form of oronasal fistulas, as well as necrosis and fractures of the jaw bones.

Radiation therapy Radiation therapy is used to treat small CCs or tumors in which even microscopically it is not possible to determine the boundaries of spread. Radiation therapy, which is quite effective in PCI, does not give very good results in the treatment of FSA and ZM. One prospective study of 105 dogs with PCI, FSA, and LM examined the effectiveness of treatment with X-ray irradiation at a total dose of 48 Gy in 4 Gy increments every other day for 4 weeks. It has been shown that the lifespan of animals is determined mainly by the size of the tumor at the beginning of therapy. This is why it is important to start using radiation therapy in the early stages of the disease. Since the effect of radiation is short-lived, re-irradiation is recommended for those tumors that did not respond well to the initial treatment. In such cases, one can hope for an active secondary response.

It should be noted that radiation therapy alleviates the course of the disease, improves the patient’s quality of life and allows delaying the euthanasia of the sick animal. In most veterinary clinics, the commonly used radiation regimen is 15-21 doses, but a more aggressive regimen (fewer exposures, but with a larger single dose) can be used. In case of MM, an aggressive irradiation regimen (once a week) gives an effect that is practically no different from the effect of the usual regimen, but allows reducing the patient’s time in the clinic.

carcinoma

Figure 12. Large diffuse squamous cell carcinoma located near the frenulum and extending to the base of the tongue (Figure 12 a). Since such a tumor cannot be completely removed, and the likelihood of metastases is high, the prognosis for the outcome of the disease is unfavorable. The dog, however, managed to achieve remission with the help of palliative radiation therapy, the results of which 6 months after the course are presented in Figure 12 b. Although the animal's tongue increased in size and became fibrous, histological analysis of the biopsies did not reveal the presence of tumor cells at the site of the tumor 6 months after the course of radiation therapy. Radiation therapy is an effective palliative treatment option when the tumor is not resectable, such as large tumors in the midline of the hard palate (Figures 11 and 12). However, there is other information in the literature - 7 cats with PCI received radiation therapy with doses of 8 Gy on days 0, 7 and 21 from the moment the disease was diagnosed; in 6 animals (85.7%) activation of tumor growth was observed. Thus, it is better not to use high-dose radiation to treat cats with PCI. It has been established that artificial hyperthermia improves the effectiveness of radiation therapy for tumors, but this method is not yet available for use in veterinary practice.

Drug therapy

The death of patients from oral cancer (for example, CC or FSA) is most often a consequence of the development of the main tumor, rather than its metastases. Therefore, it is believed that chemotherapy is less effective compared to local treatment of the underlying tumor. People with tumors in the head and neck area are given additional chemotherapy with drugs such as mitoxantrone (mitosantrone), 5-fluorouracil (5-FU), and cisplatin to increase the effectiveness of radiation therapy. These anticancer drugs may also be useful for veterinary patients. However, there are few reports on the effective use of antitumor drugs in veterinary practice. It has been established that systemic use of 5-FU is contraindicated in cats, as it causes side neurotoxic effects in these animals.

In cats with unresectable PCI, the effectiveness of radiation therapy can be increased by combining radiation and chemotherapy with mitoxantrone. The average survival time of animals treated with this combination treatment was shown to be 6 months, with 30% of cats surviving for 1 year. However, for malignant neoplasms in the oral cavity in cats and dogs, the use of chemotherapy alone is ineffective.

The use of piroxicam (a drug from the group of non-steroidal anti-inflammatory drugs, NSAIDs) had a beneficial effect in palliative therapy for PCI. The study involved 17 dogs with oral CC. With the help of piroxicam, it was possible to achieve complete resorption of the tumor in one animal and partial resorption in two (in one dog the PCI was localized on the tongue, in the other on the tonsils). The median and mean duration of therapy until the therapeutic effect disappeared was 180 days and 223 days for dogs. In addition to the animals mentioned, in another 5 dogs the disease stopped progressing after a course of piroxicam therapy. In this case, the optimal dosage of piroxicam with preserved kidney function is 0.3 mg/kg body weight per day per os, for cats - the same amount, but 1 time per 48 hours. Since complications such as ulcers of the gastric mucosa may occur during the treatment of NSAIDs, some researchers recommend the additional use of prostaglandin analogues (for example, misoprotil) during piroxicam therapy. In general, drug treatment for oral FSA or LM is ineffective.

The most encouraging results for the use of chemotherapy for the treatment of MG in dogs were recently obtained by Rassnick et al. The study involved 27 dogs with LM, and in 25 animals malignant neoplasms were localized in the oral cavity. Animals were treated with carboplatin between 1989 and 2000. (300-350 mg/m2 body surface, IV doses, every 21 days). In 28% of cases, significant remission of the disease was achieved. Thirteen dogs with oral ulcers were treated with carboplatin after surgical removal of the primary tumor. In this group of animals, the median and mean survival time after surgery were 57 and 299 days, respectively. Based on these data, the authors concluded that carboplatin is very effective in the treatment of large melanomas and can be used as an additional therapy, especially in cases where the tumor cannot be completely removed or is actively metastasizing.

Another study showed the effectiveness of intravenous melphalan in the treatment of MG in a group of 11 dogs. In 3 animals, the use of this antitumor drug caused remission, which lasted an average of 4 months (22). Other antitumor drugs (doxorubicin, mitoxantrone, cisplatin) are ineffective in chemotherapy for cancer in dogs. As for cats, the use of a combination of doxorubicin and cyclophosphamide gave complete remission in 1 case and partial remission in 3 cases (9 cats with oral ulcers took part in the study). At the same time, the toxic side effects of the drugs were within acceptable limits.

The effectiveness of local antitumor chemotherapy in the treatment of neoplasms in the oral cavity in dogs and cats was studied. Dogs with CM were injected directly into the tumor with a collagen-based gel containing cisplatin in combination with adrenaline (which has a vasoactive effect). Injections were given to 20 animals at 1-2 week intervals. In 70% of dogs there was a significant improvement in condition, and in 50% of animals the tumor completely disappeared. Compared to control dogs (who had similar tumors treated with traditional methods), animals treated with local chemotherapy experienced an increase in average life expectancy. When the tumor completely disappeared, dogs lived an average of 51 weeks after treatment, while animals in the control group lived only 10.5 weeks (23). The effectiveness of collagen gel with cisplatin brand “IntraDose” (from Matrix Pharmaceutical Inc., USA) for the treatment of FSA is currently being studied. This drug will soon be available for sale. Photodynamic therapy

Photodynamic tumor therapy (PDT) involves infusion, systemic administration, or application of a photosensitizing substance. 24-48 hours after administration of the photosensitizer, the patient is irradiated with light with a specially selected spectral composition (to activate the agent). Unfortunately, the use of PDT in veterinary practice is limited. The method is used only in some cancer centers and university veterinary clinics in the United States. The first published results on the use of PDT for the treatment of oral PCI in dogs are encouraging. Thus, PDT in 12 dogs with PCI caused remission with an average duration of more than 17 months in 8 cases. In addition, compared to radiation therapy, PDT requires significantly shorter patient hospitalization and provides excellent cosmetic results (Figure 13). However, the experience of using PDT for the treatment of PCI in the oral cavity in cats, accumulated in the author’s clinic, indicates that this method is not very effective.

Immunotherapy/gene therapy

Methods for stimulating the immune system during tumor therapy are one of the main areas of research in the field of medical and veterinary oncology. In a veterinary clinic, oral cavity tumors are most effectively treated with immunological methods. It has been shown that dogs with such neoplasms experience remissions after stimulation of the immune system with preparations of corynobacteria or liposome-encapsulated muramyl tripeptides (L - MTP - PE). The use of antitumor vaccines and cytokine therapy (interleukin-2 or GM - CSF) has yielded encouraging results. It is possible that further clinical trials will lead to the emergence of affordable methods for treating tumors, applicable in cases where traditional methods are ineffective or are not available for financial reasons.

Lymphoma in cats

Lymphoma is the most common cancer seen in cats. Lymphoma is a type of blood cancer that occurs when lymphocytes multiply uncontrollably. Lymphocytes are white blood cells that protect the body from infection. In cats, lymphoma usually affects:

Intestines;
Nasal cavity;
Lymph node;
Kidneys;
Liver.

Feline leukemia virus (FeLV) was one of the leading causes of lymphoma in cats before the development of the FeLV vaccine. Thus, the FeLV vaccine not only protects cats from FeLV, but also indirectly protects them from some forms of lymphoma.

In addition to the fact that this type of cancer is sometimes preventable, lymphoma is also one of the most treatable types of cancer. Chemotherapy is the standard treatment for most forms of lymphoma, and cats treated for lymphoma generally have a very high quality of life. Lymphoma is typically very sensitive to chemotherapy, and studies show that up to 75% of cats treated with chemotherapy will go into remission, according to the Animal Cancer Center. Approximately one third can achieve remission for more than 2 years with aggressive treatment. Ultimately, response rates and duration of remission vary by site and type.

Diagnosis of squamous cell carcinoma

To establish an accurate diagnosis, a comprehensive study is carried out. This allows you to determine which disease is developing in the animal: squamous cell carcinoma or hyperplasia. First, the doctor conducts an external examination and takes a smear of the mucous membrane for histological examination. Cytology is also performed to study pathological cells. In addition, an impression of the ulcer and a biopsy is taken. To identify the spread of metastases, a biochemical blood test is prescribed. The appearance of secondary foci of cancer is detected using radiography. It is used to examine the lungs and lymph nodes. To establish the shape, growth pattern and development of the disease, magnetic resonance and computed tomography are performed. Veterinarians also use lymph node biopsies for histological and cytological examination.

The first steps of a pet owner

Be sure to contact your veterinarian and show your pet to a specialist. At the clinic, he will undergo a thorough examination, involving, if necessary, various specialists, including an oncologist. The main treatment method in such cases will be surgery, which entails the removal of healthy tissue. If we are talking about the affected tongue or fingers, then they are completely removed. Before any such operation, the animal will undergo additional examinations, and then chemotherapy may also be prescribed.

How to Help Your Cat Fight Cancer

To help your cat win the battle against cancer, familiarize yourself with the most common signs and symptoms of cancer and make sure your cat visits your veterinarian regularly. Your veterinarian will address any concerns, analyze “bumps” and “swellings,” and look for subtle signs of disease. Your veterinarian may also suggest additional tests such as blood tests, urine tests, radiographs (X-rays) and/or a biopsy if cancer is suspected. This is especially important since some of the early signs of cancer may be missed by the untrained eye, and cancer tends to have a better prognosis when diagnosed and treated early. Between visits, pay attention to any physical or behavioral changes in your cat and report them to your veterinarian immediately.

Recent advances in veterinary oncology have allowed us to treat cancers that were previously completely untreatable. It is important to know that in animals, quality of life is the most important factor guiding cancer treatment. Treatment protocols for animals are less aggressive than for humans, and thus significant side effects are unacceptable. Your veterinarian can refer you to a veterinary oncologist who has access to the latest treatment protocols and may even suggest ongoing clinical trials that may help your cat.

To learn more about cancer in cats, talk to a qualified veterinarian by visiting our veterinary clinic.

If you have any questions or concerns, you can always visit or call our veterinarian - they are your best resource for ensuring the health and well-being of your pets.

Fibrosarcoma in cats

Fibrosarcoma is another type of cancer in cats. Fibrosarcoma is an aggressive tumor that develops from fibrous connective tissue. Fibrosarcoma develops at the site of injection of various necessary medications and prophylactics, where it is called feline injection sarcoma (FISS).

Fibrosarcoma may be associated with the following injections:

Vaccination against common diseases;
Corticosteroids;
Antibiotics;
Insulin;
Subcutaneous fluids.

The occurrence of this complication is quite rare, according to estimates from the Veterinary Medical Association, about 1 case per 10,000 - 30,000 vaccinations. However, veterinarians will limit the frequency of vaccinations and direct where vaccines should be administered. Additionally, they may suggest specific vaccines (especially those that do not contain aluminum) to help reduce injection site irritation, which appears to increase the risk of FISS. These steps can be taken to reduce the risk of fibrosarcoma at injection sites, but current thinking suggests that multiple risk factors are likely involved, including dosage and genetic susceptibility factors.

When it cannot be prevented, treatment for fibrosarcoma is major surgery with/without radiation or chemotherapy.