Brief Answer: Needs further work up Detailed Answer: Hi there Thank you for sending in your query. Did you have any symptoms when this ultrasound was performed? We need to know what is the cause of this mass. It could be benign lesion like a cyst or it could be a cancerous lesion. It may not be possible to know the etiology on an ultrasound. The next step at this point is to obtain a dedicated imaging of the kidneys. This means a CT scan or an MRI of the kidneys (with iv contrast). These tests are usually quite accurate in making the diagnosis. Before doing a CT or MRI with contrast please do blood urea and creatinine levels. Once we know the cause we can plan the further treatment. If it turns out to be a cancerous lesion , the treatment is often surgical resection. Please consult a urologist to help you in decision making. I hope this was helpful Feel free to contact me if you have any further questions Regards Dr Bhabhe

---