Department of Pathology, The University of Hong Kong, Block T, Queen Mary Hospital, 102 Pok Fu Lam Road, Pok Fu Lam, Hong Kong SAR.
Virchows Arch. 2018 Jun;472(6):907-917. doi: 10.1007/s00428-018-2314-4. Epub 2018 Feb 14.
Benign proliferations that mimic malignancies are commonly encountered during the course of assessment of small and fragmented endometrial samples. Although benign, endometrial epithelial metaplasias often coexist with premalignant or malignant lesions causing diagnostic confusion. The difficulty with mucinous metaplasia lies in its distinction from atypical mucinous glandular proliferations and mucinous carcinomas, which are associated with significant interobserver variability. Papillary proliferation of the endometrium is commonly associated with hormonal drugs and endometrial polyps and is characterised by papillae with fibrovascular cores covered by epithelial cells without cytologic atypia. They are classified into simple or complex papillary proliferations depending on the architectural complexity and extent of proliferation. Complex papillary proliferations are associated with a high risk of concurrent or subsequent hyperplasia with atypia/carcinoma. Papillary proliferations may have coexisting epithelial metaplasias and, most commonly, mucinous metaplasia and syncytial papillary change. Those with striking mucinous metaplasia overlap morphologically with papillary mucinous metaplasia. The latter has been proposed as a precursor of endometrial mucinous carcinoma. Misinterpreting the Arias-Stella reaction as a malignant or premalignant lesion is more likely to occur if the pathologist is unaware that the patient is pregnant or on hormonal drugs. Endometrial hyperplasia with secretory changes may occasionally be difficult to distinguish from the torturous and crowded glands of a late secretory endometrium. Endometrial polyps may have abnormal features that can be misinterpreted as endometrial hyperplasia or Mullerian adenosarcoma. Awareness of these benign endometrial proliferations and their common association with hormonal medication or altered endogenous hormonal levels will help prevent the over-diagnosis of premalignant and malignant lesions.
良性增生常发生在评估小且碎片化的子宫内膜样本时，这些增生类似恶性肿瘤。尽管是良性的，但子宫内膜上皮化生常与癌前病变或恶性病变共存，导致诊断混淆。黏液性化生的困难在于其与非典型黏液性腺体增生和黏液性癌的鉴别，这两者的鉴别存在显著的观察者间差异。子宫内膜乳头状增生常与激素药物和子宫内膜息肉有关，其特征是乳头有纤维血管核心，被覆无细胞学异型性的上皮细胞。根据结构复杂性和增生程度，它们可分为单纯或复杂乳头状增生。复杂乳头状增生与同时或随后发生的伴异型增生/癌的增生具有高度相关性。乳头状增生可能伴有上皮化生，最常见的是黏液性化生和合体滋养细胞样乳头状改变。那些有显著黏液性化生的病例与乳头状黏液性化生在形态上重叠，后者被认为是子宫内膜黏液性癌的前驱病变。如果病理医生不知道患者正在接受激素治疗或怀孕，那么将 Arias-Stella 反应误诊为恶性或癌前病变的可能性更大。具有分泌改变的子宫内膜增生偶尔可能难以与晚期分泌期子宫内膜的扭曲和拥挤腺体区分。子宫内膜息肉可能具有异常特征，可能被误诊为子宫内膜增生或苗勒管混合瘤。了解这些良性子宫内膜增生及其与激素药物或改变的内源性激素水平的常见关联有助于避免对癌前病变和恶性病变的过度诊断。
