What is the most appropriate next step for a 31-year-old woman with a 3-month history of bilateral nipple discharge and normal breast examination?

From the Guidelines

The most appropriate next step for a 31-year-old woman with a 3-month history of bilateral nipple discharge and normal breast examination is to reassure and do nothing, as the discharge is likely physiologic given its bilateral and provoked nature, and the patient's age and normal breast exam make malignancy less likely 1. Given the patient's symptoms and normal breast examination, the discharge is likely physiologic, which is common in women of reproductive age, with a prevalence of 4.8% to 7.4% 1. The characteristics of the discharge, being bilateral and provoked, also suggest a physiologic cause. According to the ACR Appropriateness Criteria, imaging is not indicated for evaluation of physiologic nipple discharge 1. The patient's age and normal breast exam also make malignancy less likely, as the rate of malignancy associated with pathologic nipple discharge varies widely but is generally lower in younger women 1. Therefore, reassurance and observation, with instructions to stop expressing the discharge, are appropriate, and further evaluation can be considered if the discharge changes or becomes spontaneous, unilateral, or bloody. Key points to consider in the evaluation of nipple discharge include:

• The characteristics of the discharge, such as its spontaneity, laterality, and color
• The patient's age and breast exam findings
• The presence of any underlying medical conditions or medications that could cause hyperprolactinemia
• The use of diagnostic imaging, such as mammography and ultrasound, to evaluate for underlying breast pathology, although this is not typically necessary for physiologic nipple discharge 1.

From the Research

Evaluation of Bilateral Nipple Discharge

The patient presents with a three-month history of bilateral nipple discharge, which is milky in nature and produced on applying mild pressure to the breast. Given that both pregnancy tests were negative and there are no other symptoms such as bloody or clear nipple discharge, breast lumps, or skin changes, the next steps should focus on determining the cause of the nipple discharge.

Consideration of Imaging Studies

• The use of MRI in evaluating nipple discharge, particularly when conventional imaging like mammogram and ultrasound are negative, has been highlighted in several studies 2, 3, 4.
• MRI has been shown to detect the etiology of nipple discharge in a significant percentage of cases when initial imaging is negative, and it offers advantages in visualizing the retroareolar breast and evaluating posterior lesions 2.
• However, the patient's presentation of bilateral milky nipple discharge without other alarming features may not directly align with the typical indications for MRI, which often include unilateral, spontaneous, and bloody nipple discharge.

Appropriate Next Steps

Given the information provided and the nature of the patient's symptoms:

• Reassurance and doing nothing (option a) might not be appropriate without further evaluation to determine the cause of the nipple discharge.
• Referral for bilateral breast magnetic resonance imaging (MRI) (option b) could be considered, especially if conventional imaging is negative, based on the evidence supporting MRI's role in evaluating pathologic nipple discharge 2, 3, 4.
• Referral to a breast specialist and/or surgeon (option c) might be premature without initial imaging but could be necessary depending on the findings of any initial evaluations.
• Referral for ultrasound imaging (option d) is a reasonable initial step, given its non-invasive nature and the fact that it can provide useful information about the breast tissue.
• Repeating the clinical breast examination in 2-3 months (option e) could be part of the follow-up plan but does not address the immediate need to evaluate the cause of the nipple discharge.

Decision

Considering the patient's symptoms and the evidence provided, the most appropriate next step would involve further evaluation to determine the cause of the bilateral nipple discharge. Given that the discharge is milky and bilateral, and there are no other alarming symptoms, starting with less invasive and readily available imaging like ultrasound (option d) seems reasonable. However, the decision to proceed with MRI or referral to a specialist would depend on the findings of the initial evaluation and the patient's overall clinical presentation.