1. Not Your Typical Renal Cyst
Yaolin Zhou, MD, Shi Wei, MD, PhD 
The American Journal of Medicine 
Volume 130, Issue 10, Pages e429-e432 (October 2017)
DOI: /j.amjmed
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2. Figure 1
Computed tomography (venous phase) of the abdomen and pelvis shows a large thick-walled, centrally hypodense, cystic mass (arrow) in the left portion of the horseshoe kidney.
The American Journal of Medicine  , e429-e432DOI: ( /j.amjmed )
Copyright © 2017 Elsevier Inc. Terms and Conditions

3. Figure 2
Partial nephrectomy specimen of renal mass. Microscopically, the tumor showed a predominantly trabecular growth pattern (left portion of image) with extensive necrosis (right portion of image) (A). The neoplastic cells demonstrated uniform round or ovoid nuclei with salt-and-pepper chromatin, which is classic neuroendocrine morphology (B). Mitotic figures were frequently discernable (C, arrowhead) and a high Ki-67 proliferation index (approximately 20%), as shown with the dark brown stain, indicates a more aggressive histology (D). The tumor cells were immunoreactive for pancytokeratin (brown stain) in a perinuclear dot-like pattern (E) and strongly positive for synaptophysin (brown stain) (F), both characteristic of neuroendocrine differentiation.
The American Journal of Medicine  , e429-e432DOI: ( /j.amjmed )
Copyright © 2017 Elsevier Inc. Terms and Conditions