Differential Diagnosis for Breast Pain

The patient presents with breast pain, primarily in the left breast, which is exacerbated by palpation. The following differential diagnoses are considered:

• Single most likely diagnosis
  • Fibrocystic changes: This is the most common cause of breast pain, especially in young women. The pain is often cyclic, but can be constant, and is usually exacerbated by palpation. The patient's symptoms of breast pain that worsens with palpation, without a palpable lump, support this diagnosis.
• Other Likely diagnoses
  • Hormonal fluctuations: Hormonal changes during the menstrual cycle can cause breast tenderness and pain. Although the patient's menstrual history is not provided, this is a common cause of breast pain in women of reproductive age.
  • Mastitis: Although the patient does not have fever, redness, or swelling, mastitis can present with mild symptoms, especially in the early stages. The recent history of flu and medication use could be contributing factors.
  • Breast cyst: A breast cyst can cause pain, especially if it becomes large or ruptures. The patient's sister, a nurse, was unable to determine if a lump was present, which leaves the possibility of a cyst open.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
  • Breast cancer: Although breast cancer is rare in young women, it is essential to consider it in the differential diagnosis, especially if a lump is suspected. The patient's family history is negative, but this does not rule out the possibility.
  • Inflammatory breast cancer: This rare and aggressive form of breast cancer can present with pain, tenderness, and swelling. Although the patient does not have significant swelling or redness, it is crucial to be aware of this possibility.
  • Pregnancy-related breast changes: Although the patient reports being nulliparous and not sexually active, it is essential to consider pregnancy as a possible cause of breast pain, especially if there is a chance of undiagnosed pregnancy.
• Rare diagnoses
  • Sarcoidosis: This autoimmune disease can cause breast pain and lumps, although it is a rare cause of breast symptoms.
  • Thyroid disease: Some thyroid disorders, such as hyperthyroidism, can cause breast pain and tenderness, although this is an uncommon presentation.
  • Neurogenic pain: Rarely, breast pain can be caused by nerve compression or damage, such as in the case of a thoracic outlet syndrome.