Chee Ryan K W, Wilson Mitchell P, Low Gavin
Department of Radiology & Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada.
Intractable Rare Dis Res. 2025 Aug 31;14(3):232-235. doi: 10.5582/irdr.2025.01031.
Renal oncocytomas are benign renal tumours characterized by a central stellate scar that are indistinguishable on CT/MR imaging from malignant chromophobe renal cell carcinomas (ChrRCCs). Renal oncocytomas and ChrRCCs can be separate entities but can also co-exist on a spectrum in hybrid oncocytic/ chromophobe tumours. In the past, invasive biopsy and pathologic diagnosis has been relied on to differentiate these lesion and direct management. Early research demonstrates the effectiveness of technetium 99m sestamibi (99mTc-sestamibi) single-photon emission computed tomography (SPECT)/CT in differentiating benign versus malignant renal tumours. A new diagnostic algorithm has previously been proposed to reduce unnecessary biopsy and/or targeted therapy in managing enhancing 1-4 cm renal masses by incorporating 99mTc-sestamibi SPECT/CT in management. We present a case of suspected renal oncocytoma found incidentally on surveillance imaging post-treatment of uveal melanoma. We illustrate the incorporation of the proposed diagnostic algorithm using 99mTc-sestamibi SPECT/CT for enhancing 1-4 cm renal masses into the existing diagnostic algorithm for incidental renal masses and demonstrate its use in our case of suspected renal oncocytoma.
肾嗜酸细胞瘤是一种良性肾肿瘤，其特征为中央有星状瘢痕，在CT/MR成像上与恶性嫌色肾细胞癌（ChrRCC）难以区分。肾嗜酸细胞瘤和ChrRCC可能是独立的实体，但也可在混合嗜酸细胞/嫌色性肿瘤的谱系中共存。过去，依靠侵入性活检和病理诊断来区分这些病变并指导治疗。早期研究表明，锝99m 甲氧基异丁基异腈（99mTc-甲氧基异丁基异腈）单光子发射计算机断层扫描（SPECT）/CT在鉴别良性与恶性肾肿瘤方面有效。此前已提出一种新的诊断算法，通过在管理中纳入99mTc-甲氧基异丁基异腈SPECT/CT来减少在处理直径1-4 cm的强化肾肿块时不必要的活检和/或靶向治疗。我们报告一例在葡萄膜黑色素瘤治疗后的监测成像中偶然发现的疑似肾嗜酸细胞瘤病例。我们说明了将针对直径1-4 cm强化肾肿块的使用99mTc-甲氧基异丁基异腈SPECT/CT的拟议诊断算法纳入现有的偶然发现肾肿块诊断算法，并展示了其在我们的疑似肾嗜酸细胞瘤病例中的应用。
