Retropectoral Cystic Echinococcosis: A Case Report

Cystic echinococcosis of soft tissue is rare even in endemic areas. Intermuscular and intramuscular cystic echinococcoses have been occasionally reported in the literature.
A 40-year-old male was referred to the surgery clinic of Alzahra Hospital, Isfahan, Iran, with a swelling over the right side of his chest in September 2015. In physical examination, a nontender soft bulging in depth of the right pectoralis major muscle with no skin manifestation was noticeable. The axial and coronal contrast-enhanced CT scan showed a multicystic mass lesion between the right pectoralis major and minor muscles with extension beneath the pectoralis minor muscle. The patient underwent a surgery for resection of the mass. After dissection of the pectoralis major fascia, a large cystic mass was visualized just beneath the muscle with some adhesion to the chest wall. Histopatholgic study of the surgical specimen also revealed cystic echinococcosis.
This case reveals that cystic echinococcosis should be considered in differential diagnoses of any chest wall swelling.