《Slide 85.》Phyllodes tumor, Breast
A. Brief Descriptions：
Arise from intralobular stroma; previously known as “cystosarcoma phyllodes”.
Classification: benign, low-grade malignant and high-grade malignant.
Changes suggesting malignant potential: increased cellularity, high mitotic rate, nuclear pleomorphism, stromal overgrowth, and infiltrative borders.
B. Gross Findings：
1. Well-circumscribed tumors with leaf-like pattern and fleshy appearance.
C. Micro Findings：
Leaf-like projection of stroma.
Stromal hypercellularity and presence of benign glandular elements.
Increased mitotic figures.
Robbins Pathologic Basis of Disease, 6th ed. P.1103-1104.
【 Fig. 85-1 (LP)】Circumscribed tumor with leaf-like projection.
【 Fig. 85-2 (LP)】Leaf-like pattern.Proliferating stroma covered by benign ductal epithelium.
【 Fig. 85-3 (LP)】Stromal hypercellularity and presence of benign ductal element (right upper).
【 Fig. 85-4 (HP)】Increased stromal cellularity with mitotic figures.