hair loss and erythema to identify instances of selfmutilation , which could be linked to pain . Furthermore , the veterinary team should consider concerns raised by owners , such as changes in their cat ' s personality or behaviour , as these have also been linked to unmanaged pain levels in cats ; for example , hiding , inappropriate urination , reduced energy , crying or calling [ 21 ] .
Aggressive FMTs have been widely reported to have a substantial rate of metastasis , with the most commonly affected areas being the lungs and lymph nodes . Neoplastic spread to the respiratory system can affect the patient ' s lung capacity and ventilatory ability and efficiency [ 22 ] . Secondary issues such as pleural effusion have been found in studies of FMT . Excessive fluid production due to inflammation fills the pleural space [ 8 ] , restricting lung expansion and causing respiratory distress due to the limited inspiratory volume . Clinical signs such as openmouth breathing , poor tissue saturation and acute collapse can be seen in these instances [ 23 ] . Lymphatic metastasis can be identified in enlarged regional lymph nodes ; commonly , the axillary and inguinal nodes are affected in cases of mammary neoplasia . Enlarged lymph nodes are often palpable during examination by the veterinary team . Metastatic spread within the lymphatic system is often reported with changes in the patient ' s history [ 8 ] such as decreased appetite , anorexia , lethargy and weight loss . Neoplastic spread associated with FMT has also been reported in other areas of the body , such as the liver and spleen .
Prevention
Predisposing factors
Female cats are predisposed to developing mammary cancer compared with male cats [ 5 ] . Although FMTs can be seen in males , they are considered rare . Early and even pre-pubertal neutering has been identified to substantially reduce the risk of FMT development [ 9 ] . A study conducted by Overley et al . [ 2 ] found that neutering female cats before 1 year of age reduced the risk of mammary cancer by 86 %, whereas neutering before 6 months of age reduced the risk by 91 %. However , in a study conducted by Gower [ 9 ] , 50 % of veterinary nurses were found to recommend that cats be neutered at 6 months or older , with only 5 % of veterinary nurses being aware that neutering can be safely performed in cats as young as 2 months of age .
A higher prevalence of FMT has also been associated with cats undergoing oestrus-suppression treatment using progesterone [ 24 ] , with studies linking the administration of progesterone-based medications to a tripling of the risk of FMT . A review of the human medical literature [ 25 ] concluded that the use of hormone-based contraceptive pills was unlikely to trigger mammary tumour development but might promote the growth of pre-existing breast cancers .
Neutering should be considered , if this is a viable option for the cat and the owner , as opposed to oestrus-suppression therapy [ 2 ] .
Finally , a breed-associated risk has been observed in Siamese cats ( Figure 2 ), with the potential disease prevalence being twice as high as in other breeds [ 26 ] .
Figure 2 . A breed-associated risk of feline mammary tumours has been observed in Siamese cats .
Owner education and considerations
Client education is a crucial factor in the prevention and management of mammary cancer in feline patients . Establishing a stable client relationship and maintaining effective communication strategies can assist the veterinary team in delivering client education .
A study conducted in the human medical field by van Osch et al . [ 27 ] found that patients responded in a more positive manner to medical staff who were warm and empathetic in their approach , in contrast to those who adopted a cold or formal stance . Clients may not fully apprehend the gravity of medical decisions and the associated risks – for example , neutering and its effects on the risk of FMT . This can result in both parties feeling frustrated ; however , rude or dismissive behaviour should be avoided [ 27 ] . These types of negative interactions reduce cognitive functions such as memory and attention when communicating [ 28 ] , reducing the retention of information provided and , therefore , the success of client education .
The use of additional resources can also be valuable when discussing educational matters with clients . For example , in human medicine , the use of leaflets has proven effective in improving patient satisfaction and doctor – patient communication [ 29 ] .
Additionally , studies have found that allowing people time to consider information increases knowledge uptake and retention [ 30 ] . This highlights the importance of a methodically prepared approach when discussing disease risks and treatment options with clients .
34 Veterinary Nursing Journal