High attenuation cyst on kidney, approximately 3cm. erthryopoietin elevated and wbc, rbc and hemaocrit elevated though not drastically. cancer?

Bright cyst on ct: Usually a high attenuating cyst means the cyst is bright on a CT scan. While malignancy is in the differential diagnosis there are benign causes as well, such as a hemorrhagic cyst (a cyst with blood in it). Usually such findings are followed up with additional imaging studies for better characterization and interval growth before proceeding to biopsy or resection.