Diagnostic and management challenges in a partially infarcted borderline phyllodes tumor in an adolescent female: A case report and review of literature.

Abstract

Background: Fibroadenomas (FA) and phyllodes tumors (PT) are fibroepithelial neoplasms and are difficult to differentiate radiographically and histologically. We present a partially infarcted borderline PT in an adolescent with rapid tumor enlargement within 24 hours. Tumor infarction made the diagnostic work-up difficult. Complete surgical excision is the standard of care for PTs. There is controversy regarding margin re-excision for borderline PTs. In this report, we discuss the diagnostic challenges of PT and the evolving concept of margin status on PT recurrence rate.

Case summary: A 14-year-old healthy female with no medical history presented with a painful right breast mass with no nipple discharge, trauma, or skin findings. The mass showed rapid enlargement over 24 hours, prompting a workup with ultrasound and core needle biopsy. The initial biopsy was limited due to large areas of infarction. Based on the scant viable tissue and considering the patient's age, the mass was favored to be a juvenile FA. The patient underwent excision of the mass. Final pathology confirmed a borderline PT with positive surgical margins. The patient underwent margin re-excision, which did not show any residual tumor. At the 6-month post-op visit, there was a mass-forming lesion on the breast ultrasound. Subsequent core needle biopsy showed benign breast parenchyma with scar formation. The primary goal of evaluation in pediatric breast masses is to do no harm. However, rapidly growing and symptomatic masses require a more extensive work-up including biopsy and surgical excision. We present a rapidly growing breast mass in a 14-year-old female which was diagnosed as a borderline PT on her excision specimen. The mass rapidly enlarged over 24 hours. The initial biopsy pathology was limited due to a large area of infarction. The patient underwent excision of the mass. Final pathology confirmed a borderline PT that extended into the surgical margin, resulting in an additional re-excision procedure. Accurate diagnosis prior to surgical intervention is crucial to avoid additional procedures. Although histological morphology remains the gold standard for diagnosis, immunohistochemistry and molecular studies have recently shown to improve the accuracy of diagnosis of PTs. Long-term clinical and pathologic follow-up of PTs in adolescent patients should be collectively studied to examine whether our current diagnostic criteria for PT can reliably predict tumor behavior in this age group.

Conclusion: Accurate diagnosis of PTs requires surgical excision. Tumor infarction may lead to rapid tumor enlargement, hindering the correct diagnosis. More research is needed on margin status and recurrence rate, especially in adolescent patients, to help establish the best possible care for this age group.