Phyllodes tumour (PT) is a biphasic breast neoplasm that is histologically composed of a
proliferation of stromal and epithelial cells. PT is characterised by a prominent and
exaggerated intracanalicular growth pattern with leaf-like stromal fronds that project into
stretched, arc-like epithelial-lined clefts, accompanied by stromal hypercellularity. PTs are
stratified into benign, borderline and malignant grades, with malignant PTs diagnosed when
stromal cells exhibit marked cellularity with high-grade nuclear atypia, high mitotic activity …