Differential Diagnosis for Intermittent Unilateral Shifting Fibrocystic Breast Pain

• Single Most Likely Diagnosis
  • Fibrocystic breast changes: This is the most common cause of breast pain and is characterized by lumpy or rope-like breast tissue. The pain is often intermittent, unilateral, and can shift locations, which aligns with the symptoms described.
• Other Likely Diagnoses
  • Breast cysts: These are fluid-filled sacs within the breast that can cause pain, especially if they become large or rupture. The pain can be intermittent and unilateral.
  • Mastitis: An inflammation of the breast tissue, which can cause pain, swelling, and redness. It's more common in lactating women but can occur in non-lactating women as well.
  • Breast trauma: Injury to the breast can cause localized pain, which may be intermittent and unilateral.
• Do Not Miss Diagnoses
  • Breast cancer: Although less likely to present with intermittent, shifting pain, breast cancer can cause pain and should always be considered, especially if there's a palpable mass or other concerning symptoms.
  • Phyllodes tumor: A rare type of breast tumor that can cause pain, swelling, and a palpable mass. While most are benign, some can be malignant.
  • Inflammatory breast cancer: A rare and aggressive form of breast cancer that causes the breast to look inflamed due to blockage of lymphatic vessels. It can present with pain, swelling, and redness.
• Rare Diagnoses
  • Mondor's disease: A rare condition characterized by thrombophlebitis of the superficial veins of the breast, causing pain, swelling, and a cord-like structure under the skin.
  • Fat necrosis: A condition where breast tissue dies due to injury or surgery, leading to pain, lumpiness, and sometimes skin retraction.
  • Sickle cell disease crisis: In patients with sickle cell disease, a crisis can cause breast pain among other systemic symptoms, though this would be part of a broader clinical picture.