Teruhiko Tsuru

Pharmacokinetic/Pharmacodynamic Analysis of a Hemodialyzed Patient Treated with 25 mg of Sunitinib

Sunitinib has been approved for the treatment of advanced and/or metastatic renal cell carcinoma (RCC). Information on the dosage adjustment of sunitinib for patients undergoing hemodialysis is limited. Especially, efficacy and tolerance of sunitinib at a low dose in such patients are not fully understood. Thus, we examined the effect of hemodialysis on the pharmacokinetics, safety and efficacy of 25 mg of sunitinib. The patient was a 66-year-old man diagnosed with RCC and undergoing hemodialysis. He was treated with sunitinib at 25 mg daily for 4 weeks of a 6-week cycle. There were little differences in the AUC0–24 h of sunitinib and its major active metabolite SU12662 on day 17 (on hemodialysis) and day 18 (off hemodialysis) of the first cycle. The total sunitinib concentration (sunitinib and SU12662) was approximately 50 ng/ml at a steady state in every cycle. The patient’s genotype was wild type for ABCG2 421C>A, which is associated with increased sunitinib exposure. In the following two cycles of sunitinib, computed tomography scan showed a partial response of the lung metastasis. During the first cycle, the patient developed grade 2 thrombocytopenia and leukocytopenia. After four cycles of treatment, the patient developed grade 3 fatigue and the sunitinib treatment was discontinued. Our patient on hemodialysis could be safely and effectively treated with 25 mg of sunitinib, and a total sunitinib concentration of about 50 ng/ml was maintained. The pharmacokinetics of sunitinib and SU12662 were rarely affected by hemodialysis. Therapeutic drug monitoring could be helpful during sunitinib therapy, especially in a specific population.

V11-05 LAPAROENDOSCOPIC SINGLE-SITE PARTIAL CYSTECTOMY COMBINED WITH CYSTOSCOPY FOR BLADDER PARAGANGLIOMA.

INTRODUCTION AND OBJECTIVES: We present a case report of our initial experience with laparoendoscopic single-site surgery (LESS) combined with cystoscopy for primary bladder paraganglioma. METHODS: A 41 years old woman consulted for headache and palpitation after micturition for 10 years. Ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and cystoscopy revealed a solitary 2cm mass lesion in the top of the bladder (Fig.1,2). High levels of noradrenaline were found both in plasma and urine. 123IMIBG scintigraphy showed an abnormal accumulation in the bladder. Thus, paraganglioma of the bladder was diagnosed. A LESS partial cystectomy combined with cystoscopy was performed. OCTOport ,>R was inserted through 2cm skin incision through the umbilicus, and one 2-mm port was added (Fig.3,j. Cystoscopic guidance was helpful to determine the excision line of the tumor during laparoscopic surgery,@,iFig.4,j. RESULTS: She has been free from symptom after operation. Histological examination of the resected specimen showed a paraganglioma. CONCLUSIONS: LESS partial cystectomy combined with cystoscopy for bladder paraganglioma can easily identify the margins of tumor and is safe technique.

Metastatic Prostatic Ductal Adenocarcinoma Successfully Treated with Docetaxel Chemotherapy: A Case Report

A 68-year-old man presented with gross hematuria. A papillary urethral tumor adjacent to the verumontanum was found by cystourethroscopy. Serum prostate-specific antigen (PSA) was 3.246 ng/ml. A transurethral biopsy specimen was most suggestive of a primary urothelial carcinoma of the prostate, for which a radical cystoprostatectomy was performed. The final pathology was prostatic ductal adenocarcinoma with very focal acinar features (Gleason score 5 + 4 = 9, pT3bN0M0). Local recurrence and pelvic bone metastases developed 17 months later, and his PSA rose to 10.806 ng/ml. He was treated with combined androgen blockade and radiation. Two years later, the lesion showed progressive growth. Treatment followed with docetaxel (70 mg/m2 every 3 weeks) and prednisolone 5 mg twice daily. After 10 cycles of chemotherapy, all lesions disappeared and PSA decreased to <0.005 ng/ml. Three years after chemotherapy, he maintains a complete response without any additional treatments. Docetaxel chemotherapy can be an effective treatment for patients with recurrent prostatic ductal adenocarcinoma.