Repeated recurrence of bilateral gigantomastia after subcutaneous mastectomy caused by tumoral pseudoangiomatous stromal hyperplasia: a case report and review of literature.

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon benign proliferative mesenchymal lesion of the breast with a hormonal-sensitive nature. Various manifestations of PASH, ranging from an incidental microscopic finding in a tissue biopsy to a large palpable mass or bilateral gigantomastia, have been described. For tumoral PASH, surgical excision is indicated for a growing and symptomatic mass with a small chance of recurrence. A recurrence of bilateral gigantomastia after surgical excision or reduction mammoplasty is not common but has been occasionally reported, leading to further mastectomy. Repeated recurrence of bilateral gigantomastia is extremely rare. Herein, we report a case of a 13-year-old girl who presented with the third recurrence of bilateral gigantomastia caused by tumoral PASH, after undergoing bilateral reduction mammoplasty, and later subcutaneous mastectomy. Precocious puberty occurred early in this child at the age of 9 years, which may have been a factor unmasking PASH at this young age. The incomplete removal of the PASH could also have been a recurrence risk in our case as extended masses underneath the pectoralis muscle were later identified on the MRI study. This highlights the advantage of preoperative imaging in cases with a very large tumoral PASH in order to maximize the chance of complete tumor removal.