{Reference Type}: Case Reports {Title}: Large tumoral pseudoangiomatous stromal hyperplasia with ER/PR stromal negativity in a 20-year-old female: A rare case report. {Author}: Mansour S;Abdul Rahman SA;Kazour A;Salama I;Shmayes H;Rajab S;Issa R; {Journal}: Clin Case Rep {Volume}: 12 {Issue}: 1 {Year}: 2024 Jan 暂无{DOI}: 10.1002/ccr3.8398 {Abstract}: Pseudoangiomatous stromal hyperplasia (PASH) is a rare lesion of the breast stromal tissue with unknown mechanism. Hormonal stimulation of mammary myofibroblasts is the most important theory due to stromal positivity of progesterone receptor (PR) or/and estrogen receptor (ER). We report a case of PASH with stromal PR/ER negativity.