From the Guidelines
Pseudoangiomatous stromal hyperplasia (PASH) found on breast biopsy typically requires no specific treatment if it's an incidental finding without concerning clinical or radiological features. PASH is a benign breast condition characterized by the proliferation of myofibroblasts in breast stroma, creating spaces that mimic blood vessels. For most patients with PASH, clinical follow-up with routine breast imaging according to age-appropriate screening guidelines is sufficient, as recommended by the American College of Radiology 1. However, if the PASH lesion is large, growing, symptomatic, or has discordant pathology findings with imaging, surgical excision may be recommended, typically involving a lumpectomy procedure to remove the lesion completely, as suggested by guidelines for breast cancer screening and diagnosis 1. The decision for surgery should be individualized based on symptoms, size, growth pattern, and whether there are any concerning features that raise suspicion for associated malignancy. PASH itself has no malignant potential, but it's essential to ensure that the biopsy adequately sampled the lesion to exclude other pathologies, as emphasized in guidelines for imaging after breast surgery 1. Patients should understand that PASH can sometimes recur even after surgical removal, though this is uncommon. Key considerations in managing PASH include:
- Clinical and radiological assessment to determine the need for surgical intervention
- Individualized decision-making based on patient-specific factors
- Ensuring adequate biopsy sampling to rule out other pathologies
- Patient education on the potential for recurrence and the importance of follow-up imaging.
From the Research
Implications of a Pseudoangiomatous Stromal Hyperplasia (PASH) Diagnosis
The implications of a PASH diagnosis in a breast biopsy can be understood through several key points:
- Clinical Presentation: PASH is a rare and benign mesenchymal proliferative breast lesion that can present as a palpable mass or be found incidentally on imaging 2, 3.
- Diagnostic Challenges: Imaging findings for PASH are nonspecific and can be similar to those of fibroadenoma, making diagnosis based on imaging alone challenging 2, 3, 4.
- Core Needle Biopsy: Core needle biopsy can confirm a diagnosis of PASH, but it may not always be diagnostic, especially for larger lesions or those with suspicious features 2, 3, 5.
- Surgical Excision: Surgical excision may be recommended for larger lesions, those with suspicious features, or when core needle biopsy is inconclusive 2, 3, 5.
- Association with Cancer: PASH can be associated with cancerous or precancerous lesions, highlighting the importance of thorough evaluation and follow-up 3.
- Management and Follow-Up: Management of PASH can include observation with regular follow-up, especially for smaller lesions without suspicious features, or surgical excision for larger or progressive lesions 3, 5.
- Reconstruction Options: In cases of extreme relapsing bilateral PASH, innovative surgical techniques such as skin-reducing mastectomy with immediate prepectoral implantation may be considered for optimal cosmetic outcomes 6.
Key Considerations
- The decision for surgical excision versus observation should be based on lesion size, presence of suspicious features, and patient preference 2, 3, 5.
- Close surveillance is necessary due to the potential for recurrence or progression of PASH lesions 3, 5.
- The rarity of PASH and its variable presentation underscore the need for a tailored approach to diagnosis and management 2, 3, 5.