Vascular chest wall lesion mimicking a breast tumor on screening mammograms: Report of a case.

Vascular lesions in the chest wall muscles are extremely rare and can cause diagnostic difficulties on screening mammograms. We describe a case of venous malformation of the pectoralis muscle, diagnosed during routine screening, in a 60-year-old woman. The mammograms showed a mass over the chest wall, projecting in the breast parenchyma. The ultrasound was not diagnostic. The definite diagnosis was made using MRI, and to our knowledge, only 1 similar case has been reported so far, but this is the only asymptomatic case depicted during screening services.