Department of Clinical & Biological Sciences, University of Turin at St Luigi Hospital, Orbassano, Torino, Italy.
Am J Surg Pathol. 2010 Jul;34(7):973-83. doi: 10.1097/PAS.0b013e3181e2b726.
Myxoid changes have been rarely reported both in adrenocortical adenomas and carcinomas. The recent observation by our group of an adrenal myxoid tumor with morphologically borderline features, but aggressive clinical behavior prompted us to review a series of 196 adrenocortical lesions, comprising 122 carcinomas and 74 adenomas, to define the morphologic, phenotypical and clinical characteristics of adrenocortical tumors with myxoid features. Fourteen cases, including 12 carcinomas and 2 borderline tumors, formed the basis of this report, and were characterized by a variably abundant myxoid component (from 5% to 90% of tumor) and 2 distinct cellular growth patterns: the first (10 cases), mostly associated with a predominant myxoid stromal component, was made of small cells with mild atypia arranged in cords and microcysts; the second (4 cases) was characterized by focal myxoid changes in tumors otherwise similar to conventional adrenocortical carcinoma, with large atypical cells having an eosinophilic cytoplasm and a diffuse or nodular architecture. The above mentioned patterns were absent in all adenomas reviewed. A peculiar reactivity to neurofilaments was seen, mostly associated to the presence of predominant rather that focal myxoid stromal changes, and in 40% of conventional adrenocortical carcinomas, thus representing an undescribed potential pitfall in the differential diagnosis of adrenal lesions. Myxoid adrenocortical tumors probably represent a rare but histologically and phenotipically distinct entity and, although rare cases of benign lesions are on record, they seem to be generally associated to morphologic and clinical features of malignancy.
黏液样变在肾上腺皮质腺瘤和癌中均很少见报道。我们小组最近观察到一例具有形态学交界特征但侵袭性行为的肾上腺黏液样肿瘤，促使我们回顾了一组 196 例肾上腺皮质病变，包括 122 例癌和 74 例腺瘤，以确定具有黏液样特征的肾上腺皮质肿瘤的形态、表型和临床特征。包括 12 例癌和 2 例交界性肿瘤在内的 14 例病例构成了本报告的基础，并具有以下特征：黏液样成分的含量不同（占肿瘤的 5%至 90%），且存在两种不同的细胞生长模式：第一种（10 例）主要与丰富的黏液性基质成分相关，由排列成索状和微囊状的小细胞组成，具有轻度异型性；第二种（4 例）表现为肿瘤中局灶性黏液样改变，类似于常规肾上腺皮质癌，伴有大的异型细胞，胞质嗜酸性，呈弥漫性或结节性结构。在所有回顾的腺瘤中均不存在上述模式。发现一种对神经丝的特殊反应，主要与存在丰富而非局灶性黏液性基质改变相关，且在 40%的常规肾上腺皮质癌中存在，因此在肾上腺病变的鉴别诊断中代表了一个未描述的潜在陷阱。黏液样肾上腺皮质肿瘤可能代表一种罕见但在组织学和表型上均不同的实体，尽管有良性病变的罕见病例记录，但它们似乎通常与恶性肿瘤的形态和临床特征相关。
