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Describe sino Nasal or Nasal tumours.

Canine nasal tumours account for approx 1% of neoplasms. Approximately 60-80% of all respiratory tumours are nasal or sino nasal tumours. typically an older medium to large breed dog. possibl risk factors for dogs - doliocephalic breeds, urban environments at higher risk, exposure to tobacco smoke and indoor exposure to fossil fuel combustion productions, risk factors for cats are unknown although chronic rhinitis may be an initiating factor. cats with lymphoma are typically FeLV negative. the most common types of nasal tumours are carcinomas including adenocarcinomas. Sarcomas comprise most of the remaining 1/3 including fibrosarcomas, osteosarcomas, chondrosarcomas.. Carcinomas approx 2/3. the most common type in cats is lymphoma (B cell > T cell) although carcinoma is common as well. sarcomas are rare.


Describe the biologic behaviour of nasal tumours

Most nasal tumours are characterised by progressive local invasion and late onset of metastasis. there is low rate of metastatic disease at the time of diagnosis, however the metastatic rate may be as high as 30-46% at the time of death - sites include local lymph nodes and lung, rarely other sites such as brain,kidneys, liver, skin and bones. in cats with nasal lymphoma, disease recrudescence often occurs systemically months to years following definitive treatment.


Describe the clinical signs of nasal tumours

it is very important to remember that while neoplasia is on the ddx - other nassal diseases can cause overlapping signs. Most dogs and cats present with a history of Clinical signs attributable to nasal disease however cats often also present with inappetence and weight loss. clinical signs of nasal disease may include nasal discharge, congestion, epistaxis, sneezing reverse sneezing, coughing, nasal deformity in cats, pawing at the face, stertor, ocular discharge and abnormalities, obtunded or seizures (rare). Epistaxis has many differentials - it does not automatically imply neoplasia.


What is the initial diagnostic approach to nasal tumours?

A thorough history is important when trying to determine an underlying aetiology or at least help to determine appropriate tests. information from the history should include duration and progression of signs, location of discharge, type of discharge should be characterised, response to previous treatment may be helpful, especially in a referral setting, seasonal incidence or association with another stimulus. The goal is to rule out systemic disease before doing a nasal workup.


What diagnostic tests should be done for nasal disease?

Complete blood count, chemistry profile, urinalysis, FeLV/FIV (cats), T4 (cats), BMBT( ACT, PT, PTT if indicated or severe epistaxis). Additional tests if needed depending on differentials, geographic location, risks of dog or cat, cross match and typing is severe epistaxis, blood pressure (uncommon for hypertension to be sole causE), tick titers to rule out ehrlichiiosis, particularly in cases of thrombocytopenia and epistaxis. testing for feline herpesvirus (FHV-1), feline coronavirus, chlamydia felis, cryptococcus if indicated.


Describe diagnostic imaging for nasal disease

Nasal radiographs - require general anaesthesia for accurate patient positioning. evaluation should include an assesment of 1) symmetry 2)bone or turbinate destruction 3) masses of variations in opacity 4) soft tissue changes. the boundaries of the nasal cavity should be assessed however difficult due to superimposition of structures, extensive compartmentalization, intricate nasal anatomy and wide variation in appearance of k9 and feline skulls. Nasal CT - CT is suprerior to radiographs & aids in defining the nature of disease including 1) location, 2)presence or absence of a solid or cavitated soft tissue mass, 3) osseous involvement 4) extent of disease 5) invasion into important adjacent structures (soft palate, nasopharynx, orbit, cranial vault). many staging schemes now are based on the extent of disease defined by CT.


Why is biopsy/rhinoscopy done?

Perform imaging first so that haemorrhage does not interfere with image interpretation. rhinoscopy permits direct visualization of lesions (plaques, masses), foreign bodies, and allows one to obtain biopsies with guidance. hwoever, in most dogs and cats with nasal neoplasia, rhinoscopy is unnecessary and blind pinch biopsies provide enough tissue for diagnosis. one exception may be cats with pharyngeal tumours in which retro flexing the scope is often helpful. Tissue biopsy - definitive diagnosis usually requires biosy and there are several ways to obtain - vigorous nasal flushing, blind nasal biopsy using pinch forceps, rhinoscopy guided techniques, trephination of the frontal sinus, surgical biopsy. Epistaxis will occur secondary to nasal biopsy. cytologic examination is not reccomended for definitive diagnosis.


How are nasal tumours staged?

Standard staging should include CBC, chemistry, urinalysis, FeLV, FIV, T4, 3 view thoracic radiographs, fine needle aspirates of regional lymph nodes, in cats that are diagnosed with nasal lymphoma it is very important to determine if they have true local disease or if they have any systemic disease. thus complete staging in cats with lymphoma should include all of the above plus: felv/FIV test, abdominal ultrasound, fine needle aspiration cytology if abnormalities, bone marrow aspirate, a general oncologic rule is to treat local disease with local therapies and systemic disease with systemic therapies.


What is the treatment of nasal tumours in dogs?

Radiation therapy is considered the standard of care treatment for nasal tumours. radiation is administered with external beam radiation units (cobalt-60 or linear accelerator) the prescription is typically such that patients are treated daily with RT daily for 2-4 weeks. the median survival time for dogs undergoing RT is 13-18 months. almost all tumours recur and dogs die of local disease. long term survival is possible. most dogs have an excellent quality of life following rt but suffer acute effects during and shortly after treatmnet. surgery alone is not recommended due to short benefit.


Describe the treatment of nasal tumours in cats

Radiation therapy is generally considered an integral part of treatment for cats with nasal tumours. it is the standard of care for treatment of cats with nasal carcinomas. median survival is 11-12 months. cats do extremely well with RT and have fewer side effects than dogs. chemotherapy is often administered in conjunction with RT for cats with nasal lymphoma. cats with nasal lymphomas treated with RT alone have median surviva. 1.5-2 years most cats have relapse after a few years and it typically is systemic. Radation therapy and chemotherapy for lymphoma - multidrug chemotherapy protocols are used - typically treatment is 6 months in duration. median survival time is 1.5 year.


Describe primary lung tumours

Uncommon in the dog and even more uncommon in the cat. metastatic tumours to the lungs are much more common than primary tumours in the lung in both dogs and cats. average age at diagnosis is 10-11 for dogs and 11-12 for cats. no gender predilection in dogs however older female cats may be more affected. bracycephalic dogs at increased risk. aetiology is unknown but some factors may increase risk including: bracycephalic breeds, urban environment, exposure to tobacco smoke, plutonium and other inhaled forms of radiation. Most primary lung tumours in dogs and cats are adenocarcinomas or carcininomas (20%) most primary lung tumours are solitary in the dog. up to 25% of cats can have diffuse lung involvement at the time of diagnosis. cats more likely to have metastais. cats have more undifferentiated or poorly differentiated tumours. primary lung tumours can metastasize via lymphatic or haematogenous routes or via transmigration through the airway.


Describe the route of metastasis of primary lung tumours

Via lymphatic or haematogenous routes or via transmigration through the airway. intrathoracic metastasis typically involves the tracheobronchial lymph nodes, other lung lobes. pleura, mediastinum, pericardium and other cardiac structures. intrathoracic metastasis is common but extrathoracic metastasis is rare in dogs. intrathoracic metastasis is slightly more common than extrathoracic metastasis in cats. sites of extrathoracic metastasis include liver, kidneys, spleen, bone, spinal cord and brain although any organ can be affected.


What are the clinical signs of lung tumours?

25-30% asymptomatic. common signs: coughing, dyspnea, lethargy, weight loss, inappetance ( in cats), wheezes( in cats), weakness, vomiting (cats), hemoptysis can occur but is relatively rare with primary lung tumours. many will present for signs relative to metastatic disease from the primary lung tumour e.g neurologic signs. paraneoplastic syndromes are uncommon but have been noticed; hypertrophic osteopathy - swollen limbs, lameness, heat upon palpation, significant pain. periosteal proliferation along long bones -s tarts distally and moves proximally. pathogenesis not understood. associated with lung pathology such as primary lung tumours, heartworm disease, esophageal tumours, metastatic tumours to the lungs. other signs - pneumoniia., severe leukocytosis, hypercalcaemia, fever may be a paraneoplastic syndrome, tumour induced secretin of ACTH (rare). cats often present for signs related to metastatic disease as opposed to respiratory signs.


What is lung digit syndrome?

Cats with primary lung tumorus usually sCC but other carcinomas too can present with digital lesions due to metastasis to multiple digits. in 1 report of cats with digital carcinomas, 88% were metastatic from a primary lung tumour while only 12% of cats had a primary digital carcinoma. Check thoracic radoiographs if a cat presents with digital carcinoma. approx 25% of cats present for digital lesions rather than pulmonary signs it is important to palpate libs and digits. management is aimed at controlling discomfort. amputation of the digits is rarely helpful and often additional digits become affected. overall survival time is short.


How is diagnosis of Lung tumour made with thoracic radiographs?

Always obtain 3 views (R lat, L lat, VD). The lower limit of detection of pulmonary nodules is 3-5 mm although lesions that are 1cm can be missed due to location, overlying structures, or presence of pleural effusion or atelectasis. lung masses are usually a solitary soft tissue spherical mass although some can be cavitated. caudal lung lobes are more often affected. in dogs, approximately 50-70% involve one lung lobe, 25-30% of cats have pleural effusion, with advanced signs of disease it can be difficult to determine if the animal has primary lung tumour with metastasis or metastatic disease from another site. If pleural effusion is present, always have a fluid analysis performed if thoracocentesis performed. most often it is nondiagnostic, if malignant pleural effusion is diagnosed, prognosis very poor. once a nodule is discovered; do baseline database, ultrasound, institute supportive care & monitoring, FNA aspiration for pperipherally located lung masses, CT guded FNA for centrally located lesions, transthoracic aspiration in cases of diffuse involvement carry a higher risk, aspiration cytology of the primary mass yields a diagnosis in >80-90% of cases but it rarely changes deifinitive treatment. Differentials for a lung mass do not just include neoplasia. they also include granuoma, cyst, infarct, localized haemorrhage, focal pneumonia, abscess, lung lobe torsion, differentials for disseminated interstitial nodules include: neoplasia, fungal disease, bacterial or parasitic granulomatous disease. Ct can identify tracheo bronchial lymph nodes and help to define true extent of disease. bronchoscopy can also be useful and brush cytology may yield a diagnosis in some cases.


What is the treatment & prognosis with lung tumours?

Surgery is the treatment of choice. lung lobectomy in most cases although partial lung lobectomy is sufficient for pierpheral tumours. thoracoscopic lung lobectomy can be performed for small peripherally located tumours. If tracheobronchial lymph nodes are abnormal or large or the primary mass is adjacent to these nodes, nodal extirpation should be done.Prognostic factors identified in dogs with primary lung tumours include: presence of metastasis to the lymph nodes, pleural effusion, tumours >5cm, presence of clinical signs, squamous cell carcinoma, poorly differentiated tumours. in cats prognostic factors > poorly differentiated tumours, metastasis to the digits, probably presence of metastasis to the lymph nodes. Long term survival is possible for dogs with solitary small well differentiated tumours that have not metastasized. cats tend to do worse than dogs.


What are the palliative measures for primary lung tumours?

Antitussives, bronchodilators, appetite stimulants, NSAIDS, anti angiogenics, and analgesics.


Describe Why metastatic tumours to the lung occur

The lungs are the frequent site of metastasis for both carcinomas and sarcomas. there are a number of theories as to why this is true. the lung may provide a fertile ground for development of tumours. the pulmonary capillary bed may cause lodging of tumour emboli in the lung thus encouraging tumour cells to extravasate and grow.


What are the tumours with high predilection for metastasis to the lungs

Metastatic tumours to the lungs are more ommon than primary lung tumours in both dogs and cats. tumours with high predilection for metastasis to the lungs include canine haemangiosarcoma, canine appendicular osteosarcoma, canine and feline mammary carcinomas, canine oral and nailbed melanomas, tonsillar squamous cell carcinomas in dogs, undifferentiated sarcomas and carcinomas of any origin. clinical signs are highly variable and often depend on the underlying primary tumour. coughing and excercise intolerance are often absent even in dogs with large tumour burdens. cats may present with open mouth breathing. nonspecific signs predominate 3-view thoracic radiographs reommended. Can have a variable appearance from structures to unstructured interstitial to alveolar.


What is the therapy for metastatic lung tumours?

Therapy is generally aimed at controlling clinical signs and may b e palliative in nature. chemotherapy - usually broad spectrum anticancer drugs are chosen. surgical removal of metastatic lesions is not typically performed, however there are certain cases in which metastectomy may be performed, control of primary tumour >300-360 days. <3 metastatic lesions to be removed at surgery Bisphosphonates may be used in some cases, especially canine osteosarcoma as there is some evidence to suggest its use slows the growth of metastatic lesions. bisphosphonates are drugs that reduce bone resorption. often used in people with osteoporosis. Ultimately prognosis is poor 2-3 month survival time. exceptions are with metastatic thyroid carcinomas and occasionally other slow growing neuroendocrine tumours.


Describe cardiac tumours?

Rare in dogs and even more rare in cat. tumour types: haemangiosarcoma, aortic body tumour, lymphoma, sarcoma, mesothelioma, carcionoma. haemangiosarcoma is the most common primary tumour of the heart in the dog - seen in golden retrieverrs, GSDs, typically present on emergency with pericardial effusion. aortic body tumours arise from chemoreceptors cells at the heart base. lymphoma is the most common tumour of the heart in the cat. any tumour (mammary, pulmonary, salivary gland, melanoma, squamous cell carcinoma, sarcoma) can metastasise to the heart. most dogs present clinically ill, rarely an incidental finding. Therapy generally limited - palliative eg pericardial window, chemotherapy, anti arryhthmics. definitive - surgical removal (rarely possible.) generally prognosis is poor for cardiac tumours, exceptoon is chemodectomas, survival advantage if pericardiectomy.


What is stertor

An inspiratory snoring noise associated with partial occlusion of the nasal passages, choanae or nasopharynx.


What is stridor?

A high pitched inspiratory noise associated with partial occlusion of the larynx or trachea.


What is a sneeze?

A forceful expiration that results in expulsion of foreign material from the nasal passages.


What is reverse sneezing

A paroxysmal inspiratory choking noise designed to clear foreign material from the nasopharynx.


What is epistaxis?

Nose bleed - may occur in association with local disease e.g trauma, foreign body or may be due to a systemic disease (coagulopathy, hypertension).


When is nasal discharge seen?

May be seen in association with inflammatory diseases (rhinitis) or obstructive diseases (foreign body, mass)


Describe the different types of Nasal discharge?

Serous nasal discharge is clear and acelllular. it may go undetected due to the animal licking it away. Causes - primary viral infections, allergic rhinitis, lymphocytic-plasmacytic rhinitis, foreign bodies. Sneezing can lead to discharge becoming blood tinged. mucoid n nasal discharge is clear and acellular but contains more protein than serous discharge. it reflects hyperplasia of the mucoid glands within the nasal cavity and is typically associated with the chronic disease processes such as rhinitis or adenocarcinoma. purulent discharge is tenaceous and yellow to green in coloud. cytology reveals numerous neutrophils and usually bacteria purulent discharges are sen with secondary bacterial infections, pneumonia, dental disease and congenital abnormalities such as cleft palate and immotile cilia syndrome. sanguinous reflects blood tingeing to a primary type of discharge. May be caused by sneezing where violent expulsion of air causes small capillaries to rupture or in association with conditions that cause erosion of blood vesse,s such as neoplasia or fungal infections. epistaxis represents copious bleeding where the PCV of the discharge is similar to blood. any condition causing coagulopathy may manifest with epistaxis as can hypertension and hyper viscosity syndromes such as multiple myeloma. Profound bleeding may also be seen if neoplasms or fungal plaques erode a major vessel and in association with dental disease.


Describe what Physical examination of the nose should include

patency of nasal passages - hold a cold slide infront of the nostrils and assess for condensation. Facial deformity - may suggest neoplasia, fungal infection or dental abscessation. facial pain: may be seen with neoplasia, fungal infection, trauma, foreign body. Sinus percussion: decreased resonance on percussion of the frontal sinus may reflect an accumulation of fluid or soft tissue within the sinus. apparent pain may also be detected. Nasal depigmentation may suggest fungal infection. Palatine deformity - ventral bowing suggests a nasopharyngeal mass e.g tumour, polyp, cleft palate, should be apparent. Mucous membranes - petehciation may suggest thrombocytopenia or thrombocytopathia. occular examination: check for conjunctivitis/ocular discharge, uveitis, retinal vessel tortuosity (hypertension) retinal detachment (hypertesion, trauma) retinal haemorrhage (hypertension, coagulopathy, trauma) or Exopthalmos (trauma, neoplasia, retrobulbar abscessation) lymph nodes: sub mandibular lymph nodes enlargement may be seen with neoplasia, infection, dental disease. A full examination may require general anaesthesia, in order that the dentition and palate can be fully evaluated.


Name the potential infectious causes of nasopharyngeal disease

Viral - canine distemper, adenovirus, parainfluenza virus
Feline - herpes virus 1, calicivirus
Bacterial - mixed commensals - common secondary component
Chlamydophila felis, bordetella bronchiseptica, mycoplasma spp
Fungal - aspergillus, pencilliosis, (D>C) cryptococcus (C>D)