Yom Breast Clinic, Seoul, South Korea.
Adv Exp Med Biol. 2021;1187:601-612. doi: 10.1007/978-981-32-9620-6_32.
Phyllodes tumors of breast (PTB) have been known to an uncommon and particular disease to handle owing to diagnostic ambiguity and unpredictable clinical outcome. Malignant phyllodes tumors (MPT) are diagnosed when there are marked stromal hypercellularity, atypia, increased mitoses of ≥10/10 HPFs, permeative tumor borders, and stromal overgrowth. The presence of a malignant heterologous element (MHE) places the tumor into the malignant category regardless of other histological features. Excision with negative margins should be achieved for recurrent and malignant phyllodes tumor. An ideal margin width remains to be determined, and may need to be considered in relation to factors such as tumor size and cosmesis. Without the convincing evidence of survival benefit, adjuvant RT has revealed more favorable local control rate compared with observation group. Stromal expression of Twist and Foxc2, epithelial-mesenchymal transition marker, was associated with high tumor grade and poor prognosis. Tumor-associated macrophage drives myoblast differentiation and malignant progression of PTB through a CCL18-driven signaling cascade amenable to antibody disruption. Recent targeted sequencing on PTBs provided insights into the molecular pathogenesis and genetic characterization with potential clinical implications.
乳腺叶状肿瘤（PTB）是一种不常见且特殊的疾病，由于诊断上的模棱两可和不可预测的临床结果，处理起来颇具难度。当存在明显的间质细胞增生、异型性、核分裂象≥10/10HPFs、浸润性肿瘤边界和间质过度生长时，即可诊断为恶性叶状肿瘤（MPT）。存在恶性异源成分（MHE）的肿瘤无论其他组织学特征如何，均归入恶性类别。对于复发性和恶性叶状肿瘤，应实现切缘阴性的切除。理想的切缘宽度仍有待确定，可能需要考虑肿瘤大小和美容等因素。在没有生存获益的令人信服证据的情况下，与观察组相比，辅助放疗显示出更高的局部控制率。上皮-间充质转化标志物 Twist 和 Foxc2 的间质表达与高肿瘤分级和不良预后相关。肿瘤相关巨噬细胞通过 CCL18 驱动的信号级联促进成肌细胞分化和 PTB 的恶性进展，该信号级联可通过抗体破坏。最近对 PTB 的靶向测序提供了对分子发病机制和遗传特征的深入了解，具有潜在的临床意义。
