Pulmonary agenesis with intrathoracic upper limb.

A 10-week-old boy was referred because of respiratory distress, absence of right upper limb, and a mass in the right upper chest and shoulder region. Investigations showed agenesis of the right lung; the right hemithorax was filled by a mass that was mainly cystic but also contained a deformed right upper limb. When surgery was performed at the age of 13 weeks, the mass was delivered out of the chest and removed together with the deformed limb. The upper 5 cm of the shaft of the humerus could be preserved, and the chest wall could be repaired satisfactorily. Recovery was uneventful. The embryology of the malformation is briefly discussed.