J Korean Soc Radiol.  2016 Jul;75(1):37-40. 10.3348/jksr.2016.75.1.37.

Primary Renal Carcinoid Tumor Mimicking Non-Clear Cell Renal Cell Carcinoma: A Case Report

• Joo L
• Kim SH
• Kim MJ
• Choe M

• KMID: 2327365
• DOI: http://doi.org/10.3348/jksr.2016.75.1.37

Abstract

Carcinoid tumors are neoplasms with neuroendocrine differentiation, and they are most commonly found in the gastrointestinal and respiratory systems. Primary renal carcinoid tumor has rarely been reported. Here, we present a case of primary renal carcinoid tumor manifesting as a small but a gradually enhancing mass with calcification and a cystic component.

MeSH Terms

Carcinoid Tumor*
Carcinoma, Renal Cell*
Kidney Neoplasms
Respiratory System
Ultrasonography

Figure

• 

  Fig. 1 A 55-year-old male with primary renal carcinoid tumor. A-C. USG findings show a slightly heterogeneous echogenic mass with focal highly echogenic foci and a cystic portion in the left renal cortex. D-F. Axial images of the dynamic abdominal CT scans demonstrate a well-circumscribed round mass (approximately 45 × 41 mm in size) with focal calcifications and a cystic component. The mass was nearly iso-attenuated (33 HU) on a pre-contrast image (D), and it showed gradual enhancement, 53 HU on the corticomedullary phase image (E), and 83 HU on the excretory phase image (F). G. Gross specimen of the mass shows a well circumscribed mass, measuring 4.0 × 3.9 × 2.5 cm in size. The mass is located in the upper pole cortex of the left kidney and shows direct invasion into perinephric tissue (arrow). H. The tumor cells exhibit a characteristic ribbon-like pattern (hematoxylin and eosin stain, × 200). CT = computed tomography, HU = Hounsfield unit, USG = ultrasonography

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