Yoshihide Ogawa*, Tomoharu Kobayashi, Akishima-city, Tokyo-to, Japan, Keimei Kojima, Rensuke Mannami, Makoto Mannami, Uwajima-city, Ehime-ken, Japan, Keiichi Kitajima, Kagoshima-city, Kagoshima-ken, Japan, Mitsuo Nishi, Marugame-city, Kagawa-ken, Japan, Naoki Mitsuhata, Kure-city, Hiroshima-ken, Japan Ex vivo Resection of Renal Cell Carcinoma and Restoration of the Kidney may Expand the Supply of Available Organs for Renal Transplantation
There are more than ten thousand dialysis patients waiting for kidney transplantation and the average waiting period for deceased kidney transplantation is 14 years and 10 months in Japan. To expand the donor pool, Mannami already reported 8 cases of restored kidney transplantation using kidneys after resection of renal cell carcinoma (RCC) as well as Nicol 31, Buel 14, Sener 3 cases and other single-case reports, making up more than 60 cases. More than 80% of small renal tumors (4 cm or less) are nephectomized in Japan, estimating 2,000 kidneys as such discarded every year. Nalesnik et al. recently performed the first step towards evaluating the risk of cancer transmission to optimize organ usage. To address this issue and raise awareness, we performed a prospective open clinical trial that utilized these discarding kidneys by restoring nephrectomized kidneys to be transplanted into third- party recipients. Introduction & Objectives
Materials & Methods Our study of restored kidney transplantation between the third parties had an estimated enrollment of 5 patients with one year of follow-up and was approved by Tokushukai Joint Ethics Committee in July 2009 and registered in the U.S. ClinicalTrials.gov. Donors were selected from among patients who had small renal cell carcinomas (<4 cm) and opted to undergo nephrectomy for small RCC after extensive discussion of other possible treatment modalities, including nephron-sparing procedures. After nephrectomy, the tumor was removed from each resected kidney. After careful pathological examination of the resection margin, the cut surface was sutured and repaired on the second table and the restored kidney was transplanted into an unrelated recipient. The recipient was selected by a third-party selection committee based on the blood group match, high clinical evaluation score, and negative cross-match test.
Donor kidney tumor: RENAL Nephrometry Score (Kutikiv and Uzzo. J Urol 182, 844, 2009) CaseHistologyTumor size (cm) RENAL Nephrometry score 1 51 y/o M Clear cell3.9 cm5a Low complexity 2 57 y/o M Clear cell G1>G2 INFα V- 3.5 cm5a Low complexity 3 79 y/o M Clear cell G2>G3=G1 2.0 cm6p Low complexity 4 61 y/o M Clear cell G2 INFα 3.5 cm 7p Moderate complexity 5 69 y/o M Granular3.8 cm 7p Moderate complexity
Donor renal function DonorSerum Cre mg/dl at baseline eGFRml/ min/1.73 m2 Affected kidney DTPA-GFR Remaining kidney DTPA-GFR Latest serum Cre 1 51 y/o M 0.847630.3242.601.25 2 57 y/o M 0.718844.6948.871.19 3 79 y/o M 1.3539.927.8425.973.44 4 61 y/o M 0.9463.834.6236.121.48 5 69 y/o M 0.9461.622.8023.901.40
Surgical Procedures: Nephrectomy, Irrigation with Via Span, Tumor Resection, Check Collecting System, Suture of Collecting System and Parenchyma, Approximation, and Restoration Completion ready for Transplantation
Case Age Sex Warm ischemia Cold ischemia Donor NxRestorationTransplant 1 47 y/o M 12 min6 hr 2 min5 hr 15min10 min 1 hr 56 min 2 54 y/o F 4 min 1 hr 42 min 3 hr20 min3 hr 12 min 3 62 y/o F 3 min3 hr 1 min3 hr 43 min 53 min3 hr 39 min Hx of Tx 4 66 y/o M 4 min 3 hr 4 min1 hr 52 min33 min2 hr 38 min Hx of Tx 5 55 y/o F 4 min8 hr 22 min2 hr 8 min45 min2 hr 25 min Procedure times including nephrectomy, transport, reconstruction, and transplant
Treatment Trends for T1a RCC and Potential Donor Pool in Japan In Japan Tsutsumi estimated that 2,000 kidneys with small renal cell carcinomas are nephrectomized and discarded yearly, Questionnaire survey was conducted by the JUA among teaching hospitals all over Japan in 2010. Based on the data, approximately 14,335 patients with RCC underwent surgery, accounting for 11,135 (77.7%) nephrectomized and 3,200 (22.3%) partial nephrectomized. The prevalence of T1a and T1b RCC is not certain in Japan, but the numbers of T1 RCC, < 3 cm, and < 2 cm could be estimated to be respectively 7,540, 3,273, and 1,821, if the prevalence reported by Cooperberg be applied (J Urol, 2008). Therefore, the estimation of 2,000 kidneys with small RCC by Tsutsumi appears reasonable or rather underestimated.
Conclusions Selected candidates tolerate restored kidney transplant, and achieve good renal function without tumor recurrence. The procedure seems to be acceptable for selected donors and is beneficial for patients on long-term dialysis andwaiting for a kidney. Ex vivo resection of renal cell carcinoma and restoration of the kidney may expand the supply of available organs for renal transplantation in the future. We should bridge the growing gap between the number of donor kidneys needed and the available supply by employing discarded kidneys with small RCC for renal transplantation.