End-stage renal disease after treatment with Y-90-DOTATOC

DOTA-D-Phe(1)-Tyr(3)-octreotide (DOTATOC), a newly developed somatostatin a nalogue which can be stably labelled with the beta -emitter yttrium-90, can be used for receptor-mediated internal radiotherapy. A 78-year-old woman s uffering from a carcinoid of the small intestine with multiple metastases i n the liver as well as mesenteric and supraclavicular lymph node metastases was treated with this therapy after the disease had progressed under other chemotherapy options employed years previously. The patient received four single doses of Y-90-DOTATOC at 6-week intervals. yielding a cumulative dos e of 9,620 MBq (5,659 MBq/m(2)). Restaging revealed stable metastatic disea se. Serum creatinine and urea nitrogen levels were within the normal range prior to starting and during DOTATOC therapy. However, 15 months after cess ation of DOTATOC therapy, a progressive deterioration of renal function occ urred, leading to end-stage renal disease. Urinalysis revealed a slight pro teinuria of 700 mg/day without haematuria, leucocyturia or casts. There was no obvious risk factor for chronic renal insufficiency except DOTATOC ther apy. However. it was not feasible to use kidney biopsy to prove the presenc e of radiation-induced nephritis. Intermittent haemodialysis was started as the creatinine clearance declined to below 10 ml/min. Diuresis was not aff ected. The presented case shows delayed renal insufficiency after a relativ ely low cumulative dose of Y-90-DOTATOC (5,659 MBq/m(2)). This serious adve rse event indicates that further studies are needed to evaluate which dose of Y-90-DOTATOC, under which renal protection regimen, will provide optimal management, balancing risks and benefits.