Content
- What is breast cancer in cats
- Causes of breast cancer in cats
- Feline Breast Cancer Risk Factors
- Symptoms of Breast Cancer in Cats
- Diagnosis of feline breast cancer
- Stages of breast cancer in cats
- How to Treat Breast Cancer in Cats
- How is the operation for breast tumor in cats?
- Chemotherapy for breast cancer in cats
- Breast Cancer Prognosis in Cats
- Prevention of breast cancer in cats
Do you realize that your cat has the inflamed or bulging breasts? It may be a symptom of breast cancer, the third most frequent type of cancer in this species. The early castration of cats is an important preventive measure since the vast majority of cancers are very aggressive, they are called adenocarcinomas. Therefore, detection as early as possible, along with a complete mastectomy operation, is essential to prolong our cat's survival.
Do you want to know more about how to treat thebreast cancer in cats? In this article by PeritoAnimal, we will explain what breast cancer in cats is, its symptoms, diagnosis, prognosis and its treatment possibilities.
What is breast cancer in cats
Breast cancer is the transformation of normal cells in the mammary gland into tumor cells which have greater capacity for multiplication and invasion of nearby or distant tissues through hematogenous or lymphatic pathways.
In a cat, the breast tumor is the third most frequent type of cancer, second only to lymphoma and skin tumors. Malignant are much more frequent than benign, with a percentage of 90% and high mortality.
Adenocarcinomas are the most common malignant tumors in female cats. In addition, about 35% of breast tumors at the time of diagnosis have already metastasized to nearby tissues. This metastasis can affect several organs, occurring in more than 80% of lung cases.
For more information, you can read this other PeritoAnimal article on cat cancer - types, symptoms and treatment.
Causes of breast cancer in cats
Among the causes that can lead to breast cancer in cats we find genetic factors, carcinogens, some viruses and environmental contaminants. However, the most likely cause is hormonal, as breast tumors are hormonally dependent, which means that most of them have receptors against estrogens and progestins, therefore, an early sterilization is the best prevention.
Prolonged therapy with progestogens increases the risk of presentation, as the main mechanism by which progesterone or progestogens induce tumors is overproduction of growth hormone in the mammary gland, which will directly stimulate gland growth and indirectly through insulin-linked growth factor that plays a key role in cell proliferation and transformation into neoplastic cells.
Feline Breast Cancer Risk Factors
The risk of a cat developing breast cancer increases:
- As your age increases.
- If not neutered.
- If they are neutered too late.
Any breed can be affected, but some studies indicate that Siamese female cats have twice the risk of suffering from this disease. In cats of the European breed it is also usually more frequent.
Symptoms of Breast Cancer in Cats
If you notice a swelling in the cat's breast, it's good to pay attention. the cats have a total of eight breasts divided into two cranial and two caudal pairs. Breast tumors may appear in isolation as a single, well-delimited, mobile mass or an infiltrative-like growth in deep places that have the potential to ulcerate and cause secondary infection.
It is also common for the same affected breast to present multiple nodules, although it is normal for multiple breasts to be affected (you will see swelling in the feline's breasts). About 60% of cats have more than one tumor when diagnosed. Nearby lymph nodes are also often affected.
In cats, the aggressiveness of the breast tumor is much greater than in female dogs, so that tumor cells rapidly invade the lymphatic circuit and metastasize to distant organs. You clinical signs indicative of breast tumor in cats are:
- Bulge in one or more breasts (swelling of the breast in the cat)
- Growth of these nodules.
- Tumor ulceration.
- Breast infections.
- Diseases of the lungs or other organs if the tumor has spread.
- Weight loss.
- Weakness.
Diagnosis of feline breast cancer
The usual diagnostic procedure for this disease includes blood, urine and chest radiographs. As is often the case in older female cats, it is also important to measure T4 to check thyroid status.
Although the vast majority of breast tumors in cats are malignant, given the breast lesions described above, a differential diagnosis with other pathologies that unneutered cats can present: fibroadenomatous hyperplasia, pseudopregnancy and pregnancy.
O tumor stage determination system Feline breast cancer is based on the size of the primary tumor by measuring the diameter of the mass (T), the involvement of nearby lymph nodes (N) and the metastasis to distant organs (M). All mammary glands and nearby tissues should be palpated, in addition to palpation and cytology of their regional lymph nodes, chest X-rays taken in multiple projections to assess for possible pulmonary metastasis, and abdominal ultrasound to assess for metastasis to abdominal organs.
Stages of breast cancer in cats
The stages of breast cancer in cats are:
- I: lumps less than 2 cm (T1).
- II: 2-3 cm lumps (T2).
- III: lumps larger than 3 cm (T3) with or without regional metastasis (N0 or N1) or T1 or T2 with regional metastasis (N1).
- IV: distant metastasis (M1) and the presence or absence of regional metastasis.
How to Treat Breast Cancer in Cats
As mammary adenocarcinomas in female cats are invasive and have a high rate of lymphatic involvement, a aggressive treatment. If you want to know how to treat breast cancer in cats, it is important to note that this treatment will consist of a breast removal surgery, also called mastectomy, which can be supplemented with chemotherapy and radiotherapy. Radiotherapy is a local treatment that in cats can be effective in preventing tumor recurrence.
How is the operation for breast tumor in cats?
Mastectomy in cats is more aggressive than in canine species, as must be performed throughout the affected breast chain. It is contraindicated only when the disease is very advanced and there are already metastases to distant organs, so a complete mastectomy on one side if the affected breasts are in a single chain or complete bilateral if the affected breasts are distributed in both breast chains. Also, it must be completely removed with wide margins that are essential for reducing cancer recurrence in the area and for increasing survival time.
The affected lymph nodes should also be included in mastectomy. The inguinal lymph node is removed along with the caudal mammary gland and the axillary lymph node is removed only if it is enlarged or if metastasis is detected on cytology. Once extracted, samples must be collected to send to histopathology to diagnose the type of tumor that the cat has.
In the postoperative period of mastectomy in cats, the analgesics and antibiotics they are needed to control pain, inflammation and possible infections. The first week is the most uncomfortable, especially full bilaterals. It may take several days for your cat's mood, appetite and vitality to improve. Must be placed a Elizabethan necklace not to lick the area and the stitches open. On the other hand, the possible complications are:
- Ache.
- Inflammation.
- Infection.
- Necrosis.
- Self-trauma.
- Disruption of the sutures.
- Hind limb edema.
Chemotherapy for breast cancer in cats
The best way to treat breast cancer in cats is using the principles of oncology. Adjunct chemotherapy is recommended in female cats with clinical stages III and IV or in cats with stage II or III malignant tumors. It is performed after tumor removal to delay recurrences, prolonging the remission period and delaying the appearance of metastasis. It is usually administered to every 3-4 weeks, giving a total of 4-6 cycles. Side effects that may appear in a cat undergoing chemotherapy are: anorexia and anemia and decreased white blood cells due to myelosuppression.
It might also be interesting to add a non-steroidal anti-inflammatory drug (NSAID) which inhibits cyclooxygenase type 2 (COX-2), such as firocoxib or meloxicam, as these tumors have been shown to express COX-2. On the other hand, different chemotherapy protocols have been described for feline breast tumors:
- If we are dealing with stage III or IV breast cancer: doxorubicin (20-30 mg/m2 or 1 mg/kg intravenously every 3 weeks) + cyclophosphamide (100 mg/m2 for 3 days every 3 weeks for oral route).
- With surgery + carboplatin (200 mg/m2 intravenously every 3 weeks, 4 doses) studies have shown a median survival of 428 days.
- Cats with surgery and doxorubicin in tumors smaller than 2 cm demonstrated a median survival of 450 days.
- With surgery and doxorubicin, a 1998 day survival.
- With surgery, doxorubicin and meloxicam a survival of 460 days was observed.
- With surgery and mitoxantrone (6 mg/m2 intravenously every 3 weeks, 4 doses) a survival of 450 days was determined.
It is usually accompanied by food supplements, antiemetics and appetite stimulants for preventing weight loss and remedying symptoms. At the same time, if the cat has any type of dysfunction, it must be treated.
Now that you know how to treat breast cancer in cats, next we'll talk about the prognosis.
Breast Cancer Prognosis in Cats
The average survival time from the diagnosis of breast cancer to the death of the cat is 10-12 months. Early diagnosis and early mastectomy are fundamental factors for extending survival time.
The prognosis will always be worse the larger the diameter of the tumor, so if the lump or lumps are too big, pay attention. Those with a small diameter had longer periods of remission and longer survival time. The presence of distant metastasis is always indicative of a poor prognosis.
This way, if you notice any changes in your cat's breasts, you should go to the vet to find out as soon as possible if we are facing cancer or other breast pathology. As we've already mentioned, the progression of malignant breast cancer is devastating, as in most cases it will invade our cat's lungs, making it difficult for her to breathe properly, as well as other parts of her body, and finally will cause your death.
Prevention of breast cancer in cats
The best prevention of breast cancer in the cat is a early castration, before your first heat, as it will greatly reduce the chances of suffering from this disease, which is essential, as the life expectancy of a cat with breast cancer is very low, even with treatment.
If you are sterilized after your first year of life, even if there is no reduction in the chance of breast cancer, you can prevent other diseases such as pyometra, metritis and ovarian or uterine tumors.
early castration decreases considerably the future presentation of breast cancer in cats, so that:
- It decreases by 91% if performed before 6 months, that is, they will only have a 9% chance of suffering.
- After the first heat, the probability will be 14%.
- After the second heat, the probability will be 89%.
- After the third heat, the risk of breast cancer is not reduced.
In this article you have seen what it is, symptoms and how to treat breast cancer in cats. Below, we leave a video from PeritoAnimal's YouTube channel about the most common diseases in cats that might interest you:
This article is for information purposes only, at PeritoAnimal.com.br we are not able to prescribe veterinary treatments or perform any type of diagnosis. We suggest that you take your pet to the veterinarian in case it has any type of condition or discomfort.
If you want to read more articles similar to How to Treat Breast Cancer in Cats - Causes and Symptoms, we recommend that you enter our Infectious Diseases section.