7. A 61-year-old woman presents to the pain clinic with a chief complaint of left shoulder and arm
pain 3 years after undergoing radiation therapy for breast cancer. Physical examination reveals
lymphedema of the left axilla with noticeable skin changes. Examination of the left
supraclavicular area precipitates a sharp pain that radiates down her left arm. Which of the
following is her likely diagnosis?
(A) Tumor metastasis
(B) Cervical radiculopathy
(C) Reflex sympathetic dystrophy
(D) Thrombangitis obliterans
(E) Radiation-induced plexopathy