ABSTRACT
Mesenchymal tumors encompass a diverse group of neoplasms that grow from any tissues derivative of the mesenchyma without organ specificity. Pulmonary hamartoma (PH) is a benign neoplasm that contains varying amounts of at least two mesenchymal elements together with respiratory epithelium entrapped by expanding mesenchymal growth. PH is typically a slow-growing, solitary, well-circumscribed, unencapsulated nodule with smooth or lobulated margins occurring in the periphery of the lung and endobronchial hamartoma accounts for only 5" of cases. Infiltration of lymphangioleiomyomatosis (LAM) cells into the blood vessels results in accumulation of hemosiderophages. LAM may develop sporadically or in association with tuberous sclerosis complex (TSC), which affects about 1.5 to 2.0 million people worldwide and occurs in about 1 of every 6,000 births. TSC is an autosomal dominant syndrome characterized by hamartoma formation in multiple organ systems, cerebral calcifications, seizures, and cognitive defects.
