A 48-year-old woman is undergoing evaluation of right nipple discharge that was first noticed last week during a clinical breast examination. The patient has schizophrenia, which was diagnosed in her 20s and is well controlled with antipsychotic therapy. She also takes acetaminophen intermittently for headaches. The patient plays tennis and goes to kickboxing classes regularly. She does not use tobacco, alcohol, or illicit drugs. Family history is significant for a paternal aunt who died from metastatic breast cancer at age 50. BMI is 28 kg/m². Vital signs are normal. On physical examination, scant reddish-brown fluid is expressed from the right breast. There are no breast masses and no supraclavicular or axillary lymphadenopathy. Which of the following is the most likely cause of this patient's findings?

Question

A 48-year-old woman is undergoing evaluation of right nipple discharge that was first noticed last week during a clinical breast examination.  The patient has schizophrenia, which was diagnosed in her 20s and is well controlled with antipsychotic therapy.  She also takes acetaminophen intermittently for headaches.  The patient plays tennis and goes to kickboxing classes regularly.  She does not use tobacco, alcohol, or illicit drugs.  Family history is significant for a paternal aunt who died from metastatic breast cancer at age 50.  BMI is 28 kg/m².  Vital signs are normal.  On physical examination, scant reddish-brown fluid is expressed from the right breast.  There are no breast masses and no supraclavicular or axillary lymphadenopathy.  Which of the following is the most likely cause of this patient's findings?

Quizplus · Accepted Answer

11ec25c8_d9c7_ce88_bc81_bdc0b2cca2a0_MD0003_00 This patient has nipple discharge, which can be classified as either physiologic (ie, galactorrhea) or pathologic (ie, concerning for malignancy). Pathologic nipple discharge includes discharge that is unilateral, bloody, spontaneous, or associated with other breast abnormalities (eg, palpable mass, lymphadenopathy, skin changes). The most common (~50%) cause of unilateral bloody nipple discharge without a coexisting breast mass or lymphadenopathy is a benign intraductal papilloma. Intraductal papillomas are papillary projections composed of epithelial and myoepithelial cells. These cells line a fibrovascular stalk that protrudes into the breast duct lumen; twisting of the stalk causes intraluminal bleeding and subsequent bloody nipple discharge. Intraductal papillomas epithelial and myoepithelial cells On examination, intraductal papillomas are typically nonpalpable due to small size (≤1 cm) and intraductal location. Although most cases of pathologic nipple discharge are caused by benign intraductal papillomas, some breast cancers can also present with associated nipple discharge; therefore, all patients with pathologic nipple discharge require further evaluation with breast imaging. (Choice A) Infiltrating (ie, invasive) ductal carcinomas can spread into the ductal system and cause tissue necrosis and bleeding within the breast ducts; therefore, patients can have bloody nipple discharge. However, invasive breast cancer typically also causes a palpable, irregularly shaped breast mass and lymphadenopathy, making this diagnosis less likely in this patient. (Choice C) Localized breast tissue necrosis (ie, fat necrosis of the breast) can be caused by breast trauma (eg, kickboxing injury). However, associated nipple discharge is uncommon and patients typically have a firm, irregularly shaped breast mass, which is not seen in this patient. (Choice D) Localized lactotroph proliferation in the pituitary (ie, lactotroph adenoma) can present with headaches and bilateral milky nipple discharge (ie, galactorrhea) due to increased prolactin secretion. In contrast, this patient has unilateral bloody nipple discharge. (Choice E) Certain antipsychotic medications (eg, risperidone) induce dopamine blockade in the pituitary. Because dopamine normally inhibits prolactin secretion, use of these antipsychotics can lead to hyperprolactinemia and subsequent galactorrhea. Educational objective: The most common cause of unilateral, bloody nipple discharge is a benign intraductal papilloma. Patients with an intraductal papilloma typically have no associated breast mass or lymphadenopathy. However, breast imaging is required to evaluate for breast cancer (eg, infiltrating ductal carcinoma), which can also cause pathologic nipple discharge. References: Nipple discharge: the role of imaging. (http://www.ncbi.nlm.nih.gov/pubmed/26433322) Nipple discharge. (http://www.ncbi.nlm.nih.gov/pubmed/25733736) Common breast problems. (http://www.ncbi.nlm.nih.gov/pubmed/22963023)

A 48-Year-Old Woman Is Undergoing Evaluation of Right Nipple Discharge