Solitary Pulmonary Nodule Flashcards
a single, well-circumscribed, rounded dense pulmonary lesion, 3cm or less in diameter completely surrounded by pulmonary parenchyma without evidence of adenopathy or atelectasis
Small pulmonary nodule
6 independent predictors of malignancy?
- history of smoking
- older age
- history of an extrathoracic cancer at least 5 years prior to nodule detection
- larger nodule diameter ( > 1cm is suspicious)
- upper lobe location
- the presence of spiculation
- typically the periphery of lung
- less associated with pulmonary symptoms
- grow slowly, invade lymphatics & vessels sooner, increase mets
- brionchioalveolar is subtype
- women > men
adenocarcinoma
- 25-30% in central-lung near bronchus
- slow growing spreading along bronchial wall and tend to become cavitary
- sxs- cough, hemptysis, etc
- peripheral SCC often invade the chest wall
- Men > women
Squamous cell cancer
signs and symptoms of lung cancer
- cough
- weight loss
- hemoptysis
- pleuritic CP
- dsypnea
- bone pain
- pleural effusion
- clubbing
- superior vena cava syndrom
- undifferentiated with rapid growth and spread
- bulky tumors often in the periphery
- associated with necrosis, but no cavitation
- difficult to treat
Large cell
- start near the bronchus and spread widely & rapidly
- most common cause of superior vena cava syndrome
- also Pancoast tumor symptoms and paraneoplastic syndromes
- surgery is rarely the only answer, longer survival if wedged out prior to oncology treatment
- needs chemo/rads
Small cell lung cancer
- slow growing (serial CTs typically > 24 months)
- smooth, round, lobulated nodules
- minimal activity on PET scan, 25% false negatives
- surgical wedge resection of lobectomy if centrally located
carcinoid of the lung
Diagnosis of SPNs?
- 60-80% of resected pulmonary nodules are malignant
- survival is 80% at 5 years for resected malignant nodules if caught early
- infectous granulomas cause approx. 80%
- only tissue biopsy can definitively diagnose nodule
recommendation for SPN for low-risk primary
- < 4mm: no follow up
- 5-6mm: F/U chest CT in 12 months, if no change, no further follow up
- 6-8mm: F/U chest CT in 6 to 12 months and then at 18-24 months if no change
- > 8 mm: follow up at 3, 9, and 24 months or dynamic chest, CT, PET and/or biopsy
Low risk: no history of smoking or other factors
Recommendation for SPN with high risk primary
- < 4mm: F/U chest CT in 12 months, no change = no further follow up
- 5-6mm: Follow up chest CT in 6 to 12 months, and then at 18-24 months if no change
- 6-8mm: F/u chest CT in 3 to 6 months, and then at 9-12 months and 24 months if no change
- > 8mm: follow up at 3, 9 and 24 months or dynamic chest CT, PET and/or biopsy
High risk: history of smoking and/or other malignancy
- usually the result of an inflammatory response to a previous granulomatous infection, tuberculosis or atypical mycobacteria
- the most common presentation of this SPN is a harmartoma
- other causes: RA, fibrosing alveolitis, bronchogenic cysts or hemangiomas
Benign SPN
- most common benign neoplasm
- 10% of all primary tumors
- men > women, 6th decade
- CXR: solitary, smooth, lobulated, “popcorn” calcified, slow growing
- CT- calcification with central fat
- tissue biopsy needed to exlude malignancy, very hard to diagnose with FNA
Harmartoma
Important considerations to consider about size when looking at SPN on CT
- Size (directly propertional to the probablility of malignancy)
Important considerations to consider about morphology when looking at SPN on CT
Spiculated (5x more likely malignant)
- possible organizing or resolving pneumonia
Smooth (5x less likely malignant)
- Possible solitary met or carcinoid
Lobulated (benign or malignant)
- harmartoma, peripheral carcinoid, adeno ca
Calcified
- central or diffuse- benign, other patterns could represent malignancy
Popcorn like
- Harmartoma, if associated with intranodular fat
other imporant consideration of SPN CT characteristics
- number of nodules (solitary or multiple)
ground glass opacities or partly solid
- higher likelyhood of malignancy
- bronchioalveolar cell carcinoma (slow growing)
growth rate of SPN (doubling time 15-450 days for cancerous nodules
- most cases stable at two year, considered benign
PET limitations
- nodules that measure at least 8-10mm in diameter need a PET scan.
- Smaller nodules have an increased risk for false negative reading
- false positive for inflammatory/ infectioius disease
- two malignant lesions that produce a false negative PET (bronchioloalveolar, carcinoid)
What is the primary method of SPN evaluation
CT scan: Initial scan should always be done without contast as contrast blurs the mass
Benefits of PET scanning?
- a PET scan could avoid unneccessary throacotomy in approx. 1 in 5 pts
- it is estimated that 50% of patients will have a change in staging as a result of pet scanning, with two thirds being upstaged
- PET scan results could afford some patients he benefit of neoadjuvent therapy and others will avoid an unneccessary surgery
ways to obtain tissue biopsy?
- Bronchoscopy with brushing–> 33% sensitivity
- transbronchial needle biopsy–> 67% sensitivity
- transthoracic needle aspiration—> 95% sensitivity (done with peripheral nodule)
- video associated thorascopy–> 100% sensitivity
- open thoacotomy biopsy–> 100% sensitivity
For a SPN nodule greater than 8-10mm, surgical diagnosis is preferred if:
- the clinical probability of malignancy is moderate to high
- the nodule is hypermetabolic by PET
- biopsy positive cancer dx, or unequivocal
- the fully informed patient wants a definitive diagnostic procedure
PFT show FEV1> 1.0 liters
