What Does The Following Kidney Ultrasound Report Suggest?

Please can you email me your diagnosis,if possible,on the following ecography: Kidneys are normal for size and echostructure.At middle third of rght kidney there is a nodular solid formation likely starting from cortical and moderately hyperechogenic compared with the same cortical,having maximum diameter of 38mm.It displays roundish morphology,regular and sharp edges and,at Doppler fluximeter evaluation,vascular signals at mainly perpheral distribution . Man 74 years old,hyperuricemia for about 25-30 years (four years ago uricemia 13.5 mg)never treated by drugs,only by diet(!).During the past 1-2 years pain at feet(frequently one foot) every week/month and for about 7-8 months continuosly successfully treated by Nsaids.At laboratory control all normal values except for uricemia 8.10 mg/dl and urine 2-3 erythrocyte at microscopic field(It s about five months thai I m suffering from renal colic first not every day in the last month about every day;pain ceases by muscle relaxants and/or Nsaids.The aforementioned ecography did nt disclose any stone,but I feel it at distal ureter;At ecography urine flows from ureters regularly.During the past 30 or more years I suffered by renal colic with emission of stone about 5 mm or less or more,which has never been analyzed. Also if echographist did nt see the stone,I think that it is greater than the past. I d like to know your opinion either for nodule or for hyperuricemia and nephrolithiasis. Particularly I d like to know if the echography is a picture of initial renal carcinoma(the first thing to bear in mind) or benign tumor etc. Thank you very much.Nicola Meduri