WHO有关乳头状癌的定义是：“A rare carcinoma whose invasive pattern is predominantly in the form of papillary structures.The same architecture is usually displayed in the metastases. Frequently, foci of intraductal papillary growth are recognizable.''and "papillary carcinoma arising , and limited to a mammary cyst, is to be referred to as noninvasive intracystic carcinoma."请大家帮忙翻译一下。