Liu Yang, Jiang Yue-Feng, Wang Ye-Lin, Cao Hong-Yi, Wang Liang, Xu Hong-Tao, Li Qing-Chang, Qiu Xue-Shan, Wang En-Hua
Department of Pathology, The First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.
Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
Diagn Pathol. 2016 Apr 19;11:40. doi: 10.1186/s13000-016-0490-6.
Ectopic (accessory) adrenocortical tissue, also known as adrenal rests, is a developmental abnormality of the adrenal gland. The most common ectopic site is in close proximity to the adrenal glands and along the path of descent or migration of the gonads because of the close spatial relationship between the adrenocortical primordium and gonadal blastema during embryogenesis. Ectopic rests may undergo marked hyperplasia, and occasionally induce ectopic adrenocortical adenomas or carcinomas.
A 27-year-old Chinese female patient who presented with amenorrhea of 3 months duration underwent computed tomography urography after ultrasound revealed a solitary mass in the left renal hilum. Histologically, the prominent eosinophilic tumor cells formed an alveolar- or acinar-like configuration. The immunohistochemical profile (alpha-inhibin+, Melan-A+, synaptophysin+) indicated the adrenocortical origin of the tumor, diagnosed as ectopic adrenocortical adenoma. The patient was alive with no tumor recurrence or metastasis at the 3-month follow-up examination.
The unusual histological appearance of ectopic adrenocortical adenoma may result in its misdiagnosis as oncocytoma or clear cell renal cell carcinoma, especially if the specimen is limited. This case provides a reminder to pathologists to be aware of atypical cases of this benign tumor. Although uncommon, an ectopic adrenal lesion should be included in the differential diagnosis of tumors involving the renal hilum. A misdiagnosis of this benign condition as a malignant renal tumor may have severe consequences for the patient, including unnecessary radical nephrectomy. Preoperative biopsy and appropriate immunohistochemical staining will assist in determining the origin and nature of the tumor and in avoiding intraoperative uncertainty.
异位（副）肾上腺皮质组织，也称为肾上腺残余，是肾上腺的一种发育异常。由于胚胎发育过程中肾上腺皮质原基与性腺胚基之间存在密切的空间关系，最常见的异位部位是靠近肾上腺以及沿性腺的下降或迁移路径。异位残余可能会发生明显增生，偶尔会诱发异位肾上腺皮质腺瘤或癌。
一名27岁中国女性患者，停经3个月，超声检查发现左肾门有一个孤立性肿块，随后接受了计算机断层扫描尿路造影。组织学上，突出的嗜酸性肿瘤细胞形成肺泡状或腺泡状结构。免疫组化特征（α-抑制素阳性、Melan-A阳性、突触素阳性）表明肿瘤起源于肾上腺皮质，诊断为异位肾上腺皮质腺瘤。在3个月的随访检查中，患者存活，无肿瘤复发或转移。
异位肾上腺皮质腺瘤不寻常的组织学表现可能导致其被误诊为嗜酸细胞瘤或透明细胞肾细胞癌，尤其是在标本有限的情况下。该病例提醒病理学家要注意这种良性肿瘤的非典型病例。尽管不常见，但在涉及肾门的肿瘤鉴别诊断中应考虑异位肾上腺病变。将这种良性疾病误诊为恶性肾肿瘤可能会给患者带来严重后果，包括不必要的根治性肾切除术。术前活检和适当的免疫组化染色将有助于确定肿瘤的起源和性质，避免术中的不确定性。
