Intraductal papilloma

Intraductal papilloma is a tumor that arises from the epithelium of the lactiferous ducts, with a peak incidence between 30–50 years of age. Solitary papillomas (central papillomas) are the most common cause of bloody or serous nipple discharge and are often associated with a palpable retroareolar mass; they are typically benign. Multiple papillomas (peripheral papillomas) are usually asymptomatic and diagnosed incidentally; they are often associated with atypia, DCIS, or invasive breast cancer. Characteristic features of intraductal papillomas on age-appropriate breast imaging include a well-defined intraductal mass and calcifications. Image-guided core needle biopsy is recommended in all patients for diagnostic confirmation and to assess for cellular atypia. Intraductal papillomas without atypia can be managed expectantly. Surgical excision to rule out concomitant malignancy is recommended for patients with intraductal papillomas with atypia; these patients should undergo further risk assessment for breast cancer and be considered for prophylactic chemotherapy.

• Peak incidence: 30–50 years ^[1]
• Most common cause of bloody or serous nipple discharge ^[2][3]

Epidemiological data refers to the US, unless otherwise specified.

• Solitary papilloma (also known as central papilloma)
  • Bloody or serous nipple discharge
  • Palpable retroareolar mass
• Multiple papillomas (also known as peripheral papillomas)
  • May be asymptomatic
  • Can present as a peripherally located palpable breast mass
  • Nipple discharge is uncommon.

Solitary intraductal papillomas are typically benign. Multiple papillomas are often associated with atypia, DCIS, or invasive breast cancer. ^[1][4]

Follow age-appropriate diagnostic workup for a palpable breast mass and/or nipple discharge (see “Breast mass” and “Nipple discharge” for details). The findings specific to intraductal papillomas are described here. Asymptomatic intraductal papillomas may also be detected incidentally.

Imaging

Initial imaging ^[1][4][5]

• Breast ultrasound: well-defined solid nodule or mass within a dilated lactiferous duct
• Mammography: may be normal or show a well-defined mass with calcifications

Additional imaging

Ductography

• Indication: localization of affected ducts for biopsy or surgery ^[6][7]
• Method: mammography with contrast injection to visualize the lactiferous ducts ^[8]
• Findings: filling defect(s) within the lactiferous duct, duct ectasia or obstruction, duct wall deformity ^[5][7]

Breast MRI ^[4][9]

• Indications
  • Consider in patients with nipple discharge and inconclusive findings on initial imaging
  • To assess the extent of lesions or to guide core needle biopsy
• Findings: enhancing nodule(s) within dilated lactiferous duct(s)

Core needle biopsy ^[4]

• Indication: all patients with suspected intraductal papilloma
• Findings ^[10][11]
  • Papillary structure with fibrovascular core covered by both epithelial and myoepithelial cells
  • Peripheral papillomas may be associated with cellular atypia, DCIS, or invasive breast cancer. ^[4][5]

• Intraductal papilloma without atypia ^{[4][9][12][13]}
  • Surveillance
  • Excision may be considered for symptomatic control.
• Intraductal papilloma with atypia ^[4][14]
  • Surgical excision of the affected duct(s)
  • Refer patients to oncology for further risk assessment and the possible need for prophylactic chemotherapy.

• Intraductal papilloma without atypia: good prognosis
• Intraductal papillomas with atypia: associated with an increased risk of breast cancer