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Solid Pulmonary Nodule

Solid Pulmonary Nodule
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No F/U No F/U No F/U if stable No F/U if stable No F/U if stable No F/U if stable No F/U if stable No F/U if stable 12 mo 12 mo 6-12, 18-24 mo 6-12, 18-24 mo 3-6, 9-12, 24 mo Low Risk High Risk High Risk High Risk Any Risk Low Risk Low Risk </= 4mm 4 - 6mm 6 - 8mm 8mm No F/U ExceptionstoF/U Recs Benign SolidPulmonaryNodule SolidPulmonaryNodule 3, 9, 24 mo PET/CT Biopsy Riskvs.Benefit

Exceptions to Follow Up (F/U) Recs

Young patients (<35 YOA)

– Consider a single low dose CT in 6-12 months

Patients with previous studies which demonstrate stability

– Use flowchart to determine stability

Patients with unexplained fever

– May represent infection

– Consider intervention or short term follow up

Known or suspected malignant disease

– Manage according to the clinical situation

Radiology 2005; 237:395-400

Benign Solid Pulmonary Nodule

Perifissural Nodules

– Trianglular or ovoid

– Circumscribed

– 3-9 mm in diameter

Benign 3D Ratio

– 3D Ratio = (Greatest axial dimension)/(Greatest superoinferior dimension)

– Benign 3D Ratio > 1.78


– Any calcification in a small nodule favors benign cause

– Central, laminar, or dense diffuse are reliably benign


– DDx: Hamartoma, lipoid granuloma, lipoma

Small, irregular subpleural opacities

– Elderly patients

– Apical regions

Radiology 2005; 237:395-400  AJR 2003; 180:955-964

Risk vs. Benefit

Mayo Clinic CT Screening Trial

< 3mm pulmonary nodule

– 0.2% malignant

4-7 mm pulmonary nodule

– 0.9% malignant

8-20 mm pulmonary nodule

– 18% malignant

>20 mm pulmonary nodule

– 50% malignant

Click here for a Radiation Risk Calculator

Suggested Reading

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