Pseudoangiomatous Stromal Hyperplasia (PASH) of the Breast: An Uncommon Finding in an Uncommon Patient

Abstract

Objective: Unknown ethiology Background: Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon benign breast lesion. Case Report: PASH is reported in a young female in treatment for neurological diseases with multi-drug therapy (clonazepam, valproate and risperidone). Her menstrual cycles are irregular, and she reached menarche very late. Conclusions: The higher PASH prevalence in premenopausal woman (the majority of whom are actively taking oral contraceptive pills), in 24% to 47% of men with gynecomastia and during pregnancy supports a hormonal etiology; the interaction between clonazepam, valproate, risperidone and progesterone could increase the level of progesterone that could stimulate PASH growth.

The effect of hormones on an uncommon breast disorder pseudoangiomatous stromal hyperplasia: a case report and literature review

“…To date, the cause remains uncertain; however, a leading hypothesis is that hormonal stimulation plays a role [ 8 ], specifically progesterone stimulation. The literature shows a large quantity of progesterone receptor expression in PASH stromal cells, with estrogen receptors expression being more variable [ 5 ]. The hypothesis is supported by the fact that, like our patient, there is a higher incidence of PASH in pre-menopausal women [ 5 ].…”

“…The literature shows a large quantity of progesterone receptor expression in PASH stromal cells, with estrogen receptors expression being more variable [ 5 ]. The hypothesis is supported by the fact that, like our patient, there is a higher incidence of PASH in pre-menopausal women [ 5 ]. The occurrence of PASH in males further supports the hormonal theory.…”

“…The occurrence of PASH in males further supports the hormonal theory. Pre-menopausal women additionally have a higher usage of OCPs in this population and are at the peak of hormone expression [ 5 ].…”

“…Hepatic CYP enzymes accept a wide range of substrates and multiple CYPs can contribute to the same reaction [ 9 ]. Klonopin specifically inhibits CYPs that are directly involved in progesterone metabolization [ 5 ].…”

“…Review of the literature has shown that elevated progesterone levels play a role on PASH. A current working hypothesis links the elevated progesterone levels due to oral contraceptive pills (OCPs), hormone stimulation or other medications to increased incidences of PASH [ 5 ].…”