張雲筑¹、魏子鈞^1,2、林登龍^1,2、陳光國^1,2

                                台北榮民總醫院泌尿部¹

國立陽明大學 醫學院 泌尿學科 及 書田泌尿科學研究中心²

   Yun-Chu Chang¹, Tzu-Chun Wei ^{1, 2}, Alex T. L. Lin^{1, 2}, Kuang-Kuo Chen^{1, 2}

                                Department of Urology, Taipei Veterans General Hospital¹

                 Department of Urology, School of Medicine, and Shu-Tien Urological Institute²,

                          National Yang Ming University, Taipei, Taiwan

 

Most of the current studies were aimed at single histologic type renal cell carcinoma (RCC). The simultaneous different histologic RCC were barely discussed. This study was aimed to these patient with special clinical features and outcome.

We retrospectively reviwed patient in the past 15 years who received operation for renal tumor in Taipei Veterans General Hospital, and the pathology report revealed RCC with simultaneous tow different cell type on the same kidney. The demographic data including age at surgery, sex, body weight index (BMI), comorbidities, and the pre-operative CT image findings were collected, as well as the operative method, pathologic outcome, and further outcome while follow-up.

Total 15 patients were included. The mean age at surgery was 59.3 ± 13.2 years and mean BMI was 25.3 ± 4.8 kg/m². Fourteen patients were male(86.7%) and 8 (53.3%) had their tumor on the left side. Among the comorbidities, hypertension accounts for the highest incidence ( 46.6% ) , followed by chronic kidney disease (end-stage renal disease or polycystic kidney disease, 40%) , coronary artery disease ( 26.7% ), type 2 diabetes mellitus ( 20% ) and malignant disease of other organ( 20% ). There were only 2 patients ( 13.3% ) having distinct 2 tumors from initial CT image, and the pathology reported different cell type. Other patient ( 26.7% ) had incidental the other small tumor in the specimen or there were mixed histologic feature in single tumor. The average diameter of the main tumor was 5.1 ± 2.9 cm and the smaller one 1.4 ± 1.0 cm. There were 4 patients (26.7%) having lymph node and distant metastasis at the meanwhile of diagnosis. According to the AJCC cancer staging (2010), T1a tumor represented for 20%, T1b tumor 20%, T2a tumor 26.7%, and T3a tumor 6.7%. The other smaller tumor were all of T1a stage. Most of tumor were classified as Fuhrman grade 2 ( 66.7% ), followed by grade 4 ( 20% ) and grade 3 ( 13.3% ). The operative method were mainly open radical nephrectomy ( 40% ), followed by laparoscopic radical nephrectomy (26.7%), open partial nephrectomy ( 13.3% ), robotic-assisted partial nephrectomy (13.3% ) and robotic-assisted radical nephrectomy ( 6.7% ).

The two differnt pathologic cell type of each patient were clear cell with papillary RCC ( 20% ), clear cell with chromophobe RCC ( 20% ), clear cell with mucinous tubular and spindle carcinoma ( 13.3% ), and clear cell with clear cell papillary RCC ( 13.3% ), clear cell and collecting duct carcinoma (6.7%), papillary and mucinous tubular and spindle carcinoma (6.7%), papillary and acquired cystic renal disease related carcinoma (6.7%), clear cell and acquired cystic renal disease related carcinoma (6.7%), and clear cell, papillary and mucinous tubular and spindle carcinoma (6.7%).

The average follow-up interval was 29.1 ± 21.1 months. The recurrence were found in 2 patients, one with clear cell and mucinous tubular and spindle carcinoma at the 55^th month post-OP and the other with papillary cell and acquired cystic renal disease related carcinoma at the 30^th month, respectively. Three patients with initial distant metastasis expired about 6 months after the surgery, in average.

Simultaneous two histological cell types RCC on the same kidney was relately rare. Our 15-year data showed various combinations of two histolytic cell type. However, it is difficult to correlate the prognosis and clinical outcome with the combination of cell types due to the limited data of recurrence and 5-year cancer specific mortality rate.