Primary lung tumors in dogs and cats Flashcards
Primary vs metastatic neoplasia
a primary lung tumor (right image) originates in the lung, usually a solitary tumors (or like 2 nodules)
metastatic lung cancer (left image) is more common.
Describe Primary lung tumors
Low incidence in small animals
- Mostly older animals
- Dogs mean 10-11 years
- Boxer, Doberman Pinscher, Australian
Shepherd, Irish Setter, Bernese Mountain Dog predisposed - Cats mean 12-13 year
- Persian cats predisposed
origin of most lung tumors
Mostly carcinomas of bronchoalveolar origin
Most common type of lung cancer in dogs (3)
- 85% bronchoalveolar carcinomas
- 10-15% other carcinomas
- Histiocytic sarcomas in predisposed breeds
Very rarely are small animal lung tumors benign.
Most common type of lung cancer in cats (3)
- 60-70% adenocarcinomas
- 30-40% other carcinomas
- malignant fibrous histiocytomas, sarcomas, adenomas
Very rarely are small animal lung tumors benign.
medical term for black lung disease
Pneumoconiosis
Clinical signs of primary lung tumor. (6-7)
- Cough
- Dyspnea, tachypnea
- Lethargy
- Anorexia, weight loss
- Hemoptysis
- Lameness
Primary lung tumors are Incidental findings in 30% of cases.
What is Hypertrophic osteopathy
- Rare paraneoplastic syndrome
- Periosteal new bone formation
- Associated with primary and
metastatic lung tumors - Also with non-malignant lesions
- Lameness
- Can resolve
Exact etiopathogenesis is not known.
Metastases in primary lung tumors
Actually have a High rate of metastases!
- Lymph node metastases
- Pulmonary metastases
- Pleural metastases and pleural carcinomatosis
- Distal metastases
- Dogs ~ 50% have metastasis at time of diagnosis
- Cats ~ 75% have metastasis at time of diagnosis
Describe Feline lung – digit
syndrome
- Tumor emboli travel to distant
extra-pulmonary sites - Also “MODAL syndrome”
= Muscle Ocular Digit Aorta Lung - Most commonly digits, Painful lesions in digits
- Diagnosis with FNA and X-rays/CT
= METASTATIC DISEASE, POOR PROGNOSIS!
Diagnosis of primary lung tumor.
Imaging
* X-rays
* CT
* Ultrasound
- FNA
- Biopsy / lung lobectomy
Describe CT Imaging and lung tumors.
- Detects smaller nodules in lung parenchyma than X-rays (1-2mm vs 5-7mm). Thus, helps in detecting pulmonary metastases!
- Lymph node size can be evaluated; helps in evaluating lymph node metastases!
- Helps in surgical planning; location of tumor, distance from hilus.
- Whole body CT To detect other comorbidities.
histopathology of lung tumors taken via
Ultrasound or CT guided (former more common)
Lung lobectomy
vs ultrasound guided tru-cut biopsy
vs thoracoscopic biopsy
Main Tx for primary lung tumor
Surgery!
* Lung lobectomy (either partially or fully)
* Diagnostic! (removed lobe is sent to pathology)
Do not operate if
* Metastases
* Lymphoma
Drug therapeutic Tx for primary lung tumor
Chemotherapy options:
* Vinorelbine, carboplatin (IV)
* Metronomic chemotherapy (means daily PO medication which has diff mechanism of action to IV)
TKI inhibitors (tyrosine kinase inhib.)
* Toceranib
NSAIDs
Drug therapy does not have evidence of true efficacy in dogs or cats. The aim is not curative, its to prolong quality of life.
Prognosis in dogs after dx of primary lung tumor.
Mean survival time ~ 1 year with surgery.
* Varies significantly! From 0- >1300 days (3.5 years).
Prognostic factors
* Clinical signs
* Lymph node metastasis
- Tumor stage
- Tumor grade
- Tumor size
- Histologic diagnosis
- Completeness of removal
Prognosis in cats after dx of primary lung tumor.
- Guarded to poor; mean survival time 4-5 months with surgery.
Better prognosis is some lucky cases
(>1800 days/ almost 5 years)!
Prognostic factors
* Clinical signs
* Lymph node metastasis
* Tumor stage
* Tumor grade
* Pleural effusion
carcinomas
cough
is what
what is tru-cut biopsy
A tru-cut needle biopsy, also called core biopsy, takes cylindrical tissue samples from the lesion using a special needle. A tru-cut biopsy collects tissue, while a fine needle aspiration biopsy (FNAB) collects cells.
