<s>[INST] In 1983 I lost my spleen and broke many bones in a fall that was over 500 feet. Now I have been advised that I have a mass in my left kidney that is just under 4 cm. They do not feel that it is a cyst or scar tissue from the earlier accident. I am scheduled for partial kidney removal next Tuesday. The surgery will be done robotically. Realistically do I have good odds of getting through this successfully? [/INST] Hi, Thanks for writing in. A mass lesion in the kidney of size 4 cm is best removed surgically if it cannot be confirmed to be a cyst. It is least likely to be associated with any trauma to your spleen as mentioned by you. I am sure your doctors have done a CT scan to know more about the mass in the left kidney. There must be some diagnosis made based on CT scan appearance and discussing that might help. Usually a lesion of 3 cm can be left on follow up for some time. As your mass is 4 cm, it is wise to get it removed and send it for histopathological analysis. Please do not worry about a robotic surgery, and I am sure you will come through it with minimum discomfort. Wish you a quick recovery. </s>