Editing Nipple discharge


Accounts for 5% of all breast clinic referrals, but is usually innocent

== '''Aetiology''' ==

=== Pathological (suspicious) ===

** Cancer (4-5%)
** Solitary intra-ductal papilloma (60-80%)
** Subareolar duct ectasia (20%)
** Infection

=== Physiological - galactorrhoea - mostly secondary to hyperprolactinaemia/drug-induced - generally copious, milky bilateral discharge ===

** Primary pituitary tumour
** Hypothyroidism
** Medication - primarily antipsychotics, antidepressants, opioids
** Can also get bilateral bloody discharge with these conditions
** Refer to endocrinologist

=== Lactational ===
{| class="wikitable"
|'''Medication class'''
|'''Frequency of prolactin elevation*'''
|'''Mechanism'''
|-
|'''Antipsychotics, first generation'''
|
|
|-
|Chlorpromazine
|Moderate
|Dopamine D2 receptor blockade within hypothalamic tuberoinfundibular system.
|-
|Fluphenazine
|High
|
|-
|Haloperidol
|High
|
|-
|Loxapine
|Moderate
|
|-
|Perphenazine
|Moderate
|
|-
|Pimozide
|Moderate
|
|-
|Thiothixene
|Moderate
|
|-
|Trifluoperazine
|Moderate
|
|-
|'''Antipsychotics, second generation'''
|
|
|-
|Aripiprazole
|None or low
|Dopamine D2 receptor blockade.
|-
|Asenapine
|Moderate
|
|-
|Clozapine
|None or low
|
|-
|Iloperidone
|None or low
|
|-
|Lurasidone
|None or low
|
|-
|Olanzapine
|Low
|
|-
|Paliperidone
|High
|
|-
|Quetiapine
|None or low
|
|-
|Risperidone
|High
|
|-
|Ziprasidone
|Low
|
|-
|'''Antidepressants, cyclic'''
|
|
|-
|Amitriptyline
|Low
|Not well understood. Possibly by GABA stimulation and indirect modulation of prolactin release by serotonin.
|-
|Desipramine
|Low
|
|-
|Clomipramine
|High
|
|-
|Nortriptyline
|None
|
|-
|'''Antidepressants, SSRI'''
|
|
|-
|Citalopram, fluoxetine, fluvoxamine, paroxetine, sertraline
|None or low (rare reports)
|Same as for cyclic antidepressants.
|-
|'''Antidepressants, other'''
|
|
|-
|Bupropion, venlafaxine, mirtazapine, nefazodone, trazodone
|None
|Not applicable.
|-
|'''Antiemetic and gastrointestinal'''
|
|
|-
|Metoclopramide
|High
|Dopamine D2 receptor blockade.
|-
|Domperidone (not available in United States)
|High
|
|-
|Prochlorperazine
|Low
|
|-
|'''Antihypertensives'''
|
|
|-
|Verapamil
|Low
|Not well understood. Specific to verapamil. May involve calcium influx inhibition within tuberoinfundibular dopaminergic neurons.
|-
|Methyldopa
|Moderate
|Decreased conversion of L-dopa to dopamine; suppression of dopamine synthesis.
|-
|Most other antihypertensives (including other calcium channel blockers)
|None
|Not applicable.
|-
|'''Opioid analgesics'''
|
|
|-
|Methadone, morphine, others
|Transient increase for several hours following dose
|Potentially an indirect effect of mu opiate receptor activation.
|}

== '''Concerning features''' (even with these findings, the majority are benign) ==

* Spontaneous (as opposed to expressed manually) and copious in amount
* Recurrent
* Unilateral
* Involving a single duct
* Bloody or clear


== '''On review''' ==

* Nature of discharge
* Spontaneous or provoked
* Any medications being taken
* Examination - see separate topic


== '''Differential diagnosis''' ==

* Multiple duct discharge is usually physiological or ectasia
* Even if high-risk factors are present, usually benign

== '''Investigation''' ==

* Mammography if over 40
* USS of any clinical or radiological lesions
* Bloods if suspected galactorrhoea (prolactin, renal function, TSH, b-hCG, then MRI pituitary)
* Further tests
** Ductogram?
*** Can sometimes identify filling defects within duct
** Cytology
*** Low diagnostic yield but can be done
*** Companion series says it has no role in routine management due to low sensitivity
** Core or excisional biopsy
** Endoscopic examination of ducts
*** Companion series does not sound enthusiastic


== '''Management''' ==

* Work up with examination, mammogram and USS, along with any other tests indicated based on the history
* If still unable to identify a diagnosis, '''excisional biopsy of duct in question is indicated'''
** Macrodochectomy in older women or those with completed families
** Microdochectomy in younger women intending to breastfeed - excision of just the affected duct

[[Category:Breast]]