Thoracic Cavity Tumors Flashcards
clinical signs associated with chest wall tumors?
Discomfort, weight loss, lethargy, and lameness (if cranial rib affected)
Respiratory signs (tachypnea/dyspnea)
DDX for chest wall tumors?
Osteosarcoma (OSA) - 73% of all rib tumors
Chondrosarcoma
Work up and staging of chest wall tumors?
Thoracic rads - underestimate local dz but good for met check
Cytology - can tell you its a sarcoma but must know subtype
Open wedge biopsy —> from center of field
CT for surgical planning
Treatment for chest wall tumors?
En block excision with chest wall reconstruction (max rib excision =6)
Caudal lung lobectomy may be required to permit adequate closure with substantial diaphragmatic advancement
Adjunctive chemo for dogs with OSA
How are chest walls reconstructed after tumor resection?
Cranial to mid-thorax locations —> latissimus dorsi muscle flap and external abdominal oblique muscle flap
Caudal thoracic —> diaphragmatic advancement
Prosthetic mesh augmentation depending on size and location of defect
What is the prognosis for chest wall tumors ?
OSA
- resection ALONE: MST 120days
- resection + chemo: MST 240days
CSA
-300-1000days
What are poor prognostic factors for chest wall tumors??
Tumor type and complete resection
- poor prognosis: OSA > CSA
- local tumor recurrence and met is 5.6x more likely with incomplete resection
What clinical sign is associated with lung tumors in cats?
LAMENESS = lung-digit syndrome
Mets to toes —> weight bearing digits and 3rd phalanx
Common presenting complaints in dogs with lung tumors?
Non productive cough
Exercise intolerance
Dyspnea and tachypnea - if pleural effusion develops
DDX for cat with lung tumor?
Carcinomas ( subclassified by location)
Bronchial ACA»_space; bronchoalveolar ACA
DDX for dog with lung tumors?
Carcinoma - bronchoalveolar ACA
Histocytic sarcoma (often multiple masses)
There is a lung mass in your canine patient.. what work up will you do?
Radiographs —> well demarcated and spherical solitary mass
— caudal lung lobe commonly affected
—multiple mass think LSA or histiocytic dz
Transthoracic FNA/cytology
Pretreatment biopsy usually not indicated
CT staging —> lung tumors met to tracheobronchial LN and lungs
What are the 3main radiographic presentations of lung tumors in cats?
Mixed bronchoalveolar pattern (33%)
Ill-defined alveolar mass (22%)
Pulmonary mass with cavitation (56%)
What is strongly correlated with a negative prognosis for lung tumors?
Tracheobronchial LN mets
What is the best method for accessing TB lymph node mets>
CT
Rads only 57% accurate for TBLN enlargement
Treatment for lung tumors?
Lateral thoracotomy (4th-6th intercostal) for small tumors with hilar LN biopsy -median sternotomy for large tumors and inspection of other lung lobes
Complete or partial lobectomy
What are the prognostic factors for lung tumors in dogs?
Tumor size= small (<5cm^3)
Location =peripheral is better
Presence of clinical signs —> larger tumor, worse prognosis
Clinical stage —> TBLN or pulmonary mets =worse prognosis
Histologic score of tumor —> vascular/lymphatic or higher grade = worse prognosis
What are the prognostic variables for lung tumors in cats?
Histologic grade is most important
-poorly differentiated (MST=2.5m) vs differentiated (MST=23m)
Without LN involvement - 412days
With LN involvement - 7days
Mets to toes - 67days
Pleural effusion is negative prognostic factor
What dog breeds are predisposed to histiocytic sarcoma?
Bernese mtn dog/ flat coated retriever
Histiocytic sarcomas are of what cell origin?
Malignant tumors of antigen-presenting dendritic cell origin
Histiocytic sarcomas commonly metastatize where?
LN
Kidney
Liver
CNS
What is the MST time for histiocytic sarcomas with surgical removed and adjunctive CCNU?
568 days
Clinical signs associated with cranial mediastinal tumors?
Related to mass effect —> lethargy, coughing, tachypnea, and dyspnea
Caval syndrome —> edema build up in head, neck, and forelimbs
PNS
Top DDX for cranial mediastinal tumors
LSA
Thymoma
What would you see on a work up of a thymoma?
Chem/CBC - unremarkable (anemia and hypercalcemia)
Rads - mass effect in cranial mediastinum +/- pleural effusion, megaesophagus
Transthoracic u/s with guided FNA/cytology -> neoplasic epithelial cell with large numbers of small MATURE lymphocytes and intermittent mast cells
Flow cytometry —> thymic lymphocytes differentiated from peripheral by expression of CD4 and CD8
T/F: thymoma in dogs tend to me more invasive than in cats
True
What is the gold standard treatment fo thymoma?
Exploratory thoracotomy to differentiate invasive vs non-invasive
Median sternotomy usually required due to size of tumor
—intercostal thoracotomy in cat
Non-invasive —> blunt-sharp dissection
If a thymoma is not amenable to surgery what can you do to treat?
Radiation therapy
Chemo - usually ineffective but can be attempted with steroids for invasive thymoma
Manage myasthenia gravis is present —> immunosuppressive therapy and anticholinesterase treatment
Prognosis for thymoma
Dog - good
Cat - excellent
What are poor prognostic factors for thymoma
Age: younger = worse
Megaesophagus = worse
Histologic subtype: lymphocyte rich = worse
Why do you have myasthenia gravis with thymoma?
Tumor induced antibody production which destroy ACh receptors —> muscle weakness
