Hamartoma of the Lung

 

Hamartoma is composed of tissues normally found in the location of origin but in abnormal quantity, mixture or arrangement 

Incidence

            • 0.25% in population

            • 8% of all solitary pulmonary nodules

            • Most common benign lung tumor

            • 5th and 6th decade peak  

            • Male to female ratio of 3:1 

Clinical           

            • Mostly asymptomatic

            • Cough

            • Fever (with postobstructive pneumonia)

            • Hemoptysis (rare) 

Location         

            • 2/3 are peripheral

            • Endobronchial in 10%

            • Rarely multiple 

Findings         

            • Round, smooth mass - increase in size slowly

            • Calcification in 15% - pathognomonic if popcorn type

            • Fat in 50% - detected by CT

• Calcium and fat in only 20%

 

 

Hamartoma of the right lung seen on
CT contains both calcification and fat

 

            • Cavitation extremely rare 

DDX  

            • Some other causes of a solitary pulmonary nodule

                        • Bronchial adenoma

                        • Bronchogenic carcinoma

                        • Granuloma

• Lipoid pneumonia (both contain fat but lipid pneumonia is less well-circumscribed and usually does not contain calcification)

• Solitary metastasis

• Arteriovenous malformation

• Necrobiotic nodule