Papadakis Georgios E, Tabotta Flavian, Levotanec Igor, Gonzalez Michel, Prior John O, La Rosa Stefano, Sykiotis Gerasimos P
Service of Endocrinology, Diabetology and Metabolism, CHUV, Lausanne University Hospital, Lausanne, Switzerland.
Service of Nuclear Medicine and Molecular Imaging, CHUV, Lausanne University Hospital, Lausanne, Switzerland.
J Endocr Soc. 2018 Mar 23;2(4):386-390. doi: 10.1210/js.2018-00014. eCollection 2018 Apr 1.
Technetium-99m methoxy isobutyl isonitrile (Tc-MIBI; sestamibi) single-photon emission computed tomography (SPECT)/computed tomography (CT) performed for preoperative localization of parathyroid adenomas or for other indications can reveal incidentalomas. Interpretation of such findings can be challenging, particularly when thyroid or other endocrine tumors are also present. Preoperative staging of a 59-year-old female patient with medullary thyroid carcinoma (MTC) showing moderate hypermetabolism on F-fluorodeoxyglucose positron emission tomography/CT also detected a slightly hypermetabolic pulmonary nodule (standardized uptake value normalized by body weight max = 2.0 g/mL). A sestamibi SPECT/CT performed because of concomitant primary hyperparathyroidism showed increased uptake by both the MTC and the pulmonary nodule, raising suspicion of MTC metastasis. Lung wedge resection biopsy revealed a sclerosing pneumocytoma (SPC), a rare benign pulmonary tumor not previously known to retain sestamibi. In contrast to classical knowledge that sestamibi uptake by tumors is associated with its retention by mitochondria, immunohistochemical analyses showed that the mitochondrial content of the patient's SPC was low. This case illustrates the behavior of SPC in sestamibi scintigraphy and indicates that SPC is a potential cancer mimicker in this setting.
用于甲状旁腺腺瘤术前定位或其他指征的锝-99m 甲氧基异丁基异腈（Tc-MIBI；司他米比）单光子发射计算机断层扫描（SPECT）/计算机断层扫描（CT）可能会发现意外瘤。对此类发现的解读可能具有挑战性，尤其是当同时存在甲状腺或其他内分泌肿瘤时。一名 59 岁女性甲状腺髓样癌（MTC）患者，其在 F-氟脱氧葡萄糖正电子发射断层扫描/CT 上显示中度高代谢，术前分期时还检测到一个轻度高代谢的肺结节（经体重标准化的最大标准摄取值 = 2.0 g/mL）。由于同时存在原发性甲状旁腺功能亢进而进行的司他米比 SPECT/CT 显示 MTC 和肺结节均摄取增加，这增加了 MTC 转移的怀疑。肺楔形切除活检显示为硬化性肺细胞瘤（SPC），这是一种罕见的良性肺肿瘤，此前尚不知道其会摄取司他米比。与肿瘤摄取司他米比与线粒体潴留相关的经典认知相反，免疫组化分析显示该患者 SPC 的线粒体含量较低。该病例说明了 SPC 在司他米比闪烁扫描中的表现，并表明在这种情况下 SPC 是一种潜在的癌症模仿者。
