Curious case of myxoid adipocytic tumour with ureteropelvic junction obstruction in horseshoe kidney: dilemma in management.

Isolated renal involvement by myxoid adipocytic tumour is a very rare presentation. We are reporting a horseshoe kidney with ureteropelvic junction obstruction (UPJO) with myxolipoma, which was revealed after routine histopathological evaluation postbilateral open pyeloplasty. We evaluated the patient thoroughly and after detailed discussions with the patient and parents, took the decision to manage the patient on active surveillance with interval imaging and renal dynamic scans. Managing a myxolipoma associated with UPJO is a novel experience as a surgeon, by virtue of its extreme rarity. Isolated myxolipoma of renal pelvis in association with UPJO and horseshoe kidney has never been reported earlier to the best of our knowledge. The patient has not progressed at follow-up of 30 months with occasional mild abdominal discomfort. We intend to closely monitor the patient in similar fashion. Any significant progression of disease or renal failure shall entail nephrectomy with excision of mass and subsequent renal replacement therapy.