腎門部下方の下大静脈欠損症

CONGENITAL ABSENCE OF THE POSTRENAL SEGMENT OF THE INFERIOR VENA CAVA

　63歳，男性．主訴は肉眼的血尿．画像診断上，右腎上極の充実性腫瘍と右腎静脈から下大静脈にかけての腫瘍塞栓が認められ，また，腎門部より下方の下大静脈は造影されなかった．術中所見では．下大静脈は腎門部より下方が欠損し，腫瘍塞栓は右腎静脈から残存下大静脈，左腎静脈へも進展していた．また，左腎静脈は半奇静脈に合流しており，下肢から向かう発達した側副静脈がこの半奇静脈に合流していた．

A 63-year-o1d man was referred to our department because of macrohematuria. Roentogenograhy andMRI revealed upper lobe tumor of the right kidney and tumor thrombus in the right renal vein and IVC.Cavography showed no postrenal segment of IVC, Right nephrectomy was done and there was no postrenalsegment of IVC and tumor thrombus was growing from right renal vein into the mesenteric segment of IVCand left renal vein. Left renal vein and well developed collateral veins from lower extremities were runninginto the hemiazygos vein.