- Email: [email protected]
H) RENAL MASSES
470
THE JOURNAL OF UROLOGY®
METHODS: Data from 278 LPN and 936 OPN were compared. The following variables were retrospectively recorded: surgical indication, tumor size and location, renal vessels clamping and duration, blood loss and transfusions rate, operating time, length of hospital stay, complication rates and pathological data. After matching (1:4) for tumor size, indication and tumor location (hilar vs. peripheral), the data of 137 LPN and 491 OPN were compared. RESULTS: In unmatched analysis, imperative indications (36.3% vs. 10.1%, p=0.0001) and malignant tumors (94% vs. 76.4%, p: 0.0001) were more frequent in the OPN group. In the LPN group, tumors were significantly smaller (2.8 vs. 3.4 cm, p=0.0001), less frequently in hilar location (3.8% vs. 10.4%, p=0.008), blood loss (272 vs. 518 ml, p=0.0001) and transfusion rates (7.7% vs. 13.6%, p=0009) were decreased, as well as length of hospital stay (5.9 vs. 7.6 j, p = 0.0001). By contrast, renal vessels were more often clamped (81.5% vs. 69.9%, p: 0001) for a longer period of time (28.8 vs. 19.7 min, p =0.0001), operating time was increased (156.6 vs. 147.7 min, p: 0.02) and urinary fistulas were more frequent in the LPN group (8.3% vs. 3%, p = 0.0001). In the matched setting, there was no difference between the two groups for transfusion rate (LPN: 6.7% vs. OPN: 8%). Renal vessels clamping data and operating time remained in favour of OPN. Blood loss and length of hospital stay remained in favour of LPN. Medical complication rate was significantly increased in the LPN group (16% vs. 10.4%, p: 0.07).. Despite matching, the occurrence of pT1 stages (OPN: 78% vs. NPL: 87.3%, p = 0.0001) and malignant tumours (NPO: 93.1% vs. NPL: 86.9% p: 0.02) remained significantly different. CONCLUSIONS: This is the first matched comparison between LPN and OPN. By avoiding certain bias but not all it appeared that major advantages and disadvantages of LPN remained after adjusting for surgical indication, tumor size and location. The disadvantages of LPN, particularly length of renal vessels clamping, could disappear in the future thanks to increased experience or emergence of robotic surgery. Source of Funding: None
1317 OUTCOMES OF PARTIAL NEPHRECTOMY FOR CENTRAL AND HILAR (C/H) RENAL MASSES Ross J Mason*, Ricardo A Rendon, Halifax, NS, Canada INTRODUCTION AND OBJECTIVES: Partial nephrectomy (PN) has become the standard of care for the treatment of most renal masses < 4 cm in maximum diameter and for a large portion of renal masses 4 7 cm. With continued advances in surgical techniques, PN has extended to the treatment of masses located centrally within the kidney or close to the renal hilum. This study looked at the association between tumor location and surgical outcomes in patients treated with laparoscopic or open PN at our institution. METHODS: This Institutional Review Board approved study includes 122 patients who underwent laparoscopic or open PN at our institution between January 2002 and July 2008. Clinico-pathological and post-operative data were collected for each patient. Based on pre-operative imaging, each mass was designated as C/H (touching or encroaching upon the collecting system and/or touching the major renal vessels) or peripheral (P). Bivariate logistic regression was used to assess the association between tumor location and surgical margins, and between tumor location and post-operative complications. Secondary analyses were performed to evaluate potential associations between tumor location and other clinical and pathological features. RESULTS: Laparoscopic and open PN were performed on 71(58.2%) and 51(41.8%) patients, respectively. The lesion was located in the C/H and P areas in 67(54.9%) and 55(45.1%) patients, respectively. Mean tumor size was 3.2 cm (range 1.0-7.5 cm). Positive surgical margins were found in 4(6.0%) patients with C/H masses and 4(7.3%) patients with P masses. No association was found between tumor location and positive surgical margins (p=0.773). Post-operative (PO) complications were identified in 16 (23.9%) patients with C/H masses and 13(23.6%) patients with P masses. The effect of tumor location on post-operative complications was not statistically significant (p=0.975). Secondary
Vol. 181, No. 4, Supplement, Tuesday, April 28, 2009
analyses revealed statistically significant associations between tumor location and Fuhrman nuclear grade (p=0.0092) and length of post operative hospital stay (p=0.046). CONCLUSIONS: The results of this study indicate that there is no evidence of an increased risk of identifying positive surgical margins or post-operative complications in patients with C/H vs. P located renal masses who undergo PN. Although more technically challenging, central and hilar renal location should not be a deterrent to performing PN. Source of Funding: None
1318 RADIOLOGIC VS. PATHOLOGIC TUMOR SIZE MEASUREMENTS OF RENAL CELL CARCINOMA: IMPLICATIONS ON RADIO FREQUENCY ABLATION EFFICACY Christopher W Howard*, Samer R Kalakish, Joseph A Pettus, Ashok K Hemal, Kyle A Richards, Victoriano Romero, David D Childs, Ronald J Zagoria, A. Karim Kader, Winston-salem, NC INTRODUCTION AND OBJECTIVES: CT-Guided Radio Frequency Ablation (CT-RFA) has proven to be a safe and, on short term follow-up, reliable treatment modality for renal cell carcinomas (RCCs) with a diameter less than 3.7 cm. However, treatment of tumors with a larger diameter results in an increased risk of recurrence; with each 1 cm increase in tumor diameter over 3.6 cm, the likelihood of tumor-free survival decreases by a factor of 2.19 (p < 0.001). To our knowledge, no studies have compared the measured radiologic size with the pathologic size. Historically, this was not of significant importance due to extirpative surgical resection. However, with CT-RFA it could prove instrumental in achieving complete eradication and improving tumor-free survival, especially for tumors at the upper limit of acceptability for this treatment modality. This study explores the variance between radiologic and pathologic measured size of RCC. METHODS: We retrospectively reviewed 244 cases of surgically resected RCC lesions between the years 2000 and 2008, with CT or MRI sizes of 7.0 centimeters or less that had complete pathologic size information available. RESULTS: We found numerous instances of significant overand under-estimation of size by radiologic methods. The frequency of significant underestimation increases proportional to tumor size. CONCLUSIONS:A discrepancy between radiologic measurement and pathologic measurement of RCC exists and is directly proportional to tumor size. The efficacy of CT-RFA of RCC sharply decreases with tumor sizes greater than 3.7 centimeters. Our data suggests that in some cases the actual tumor diameter may exceed the area targeted for CT-RFA treatment. This warrants an increase in treatment area safety margin proportional to the radiologic size of the tumor. Table 1: Size Discrepancy in Renal Cell Carcinoma Radiologic Size Average Discrepancy Underestimations Underestimations Range (cm) (cm) (95% CI) q 0.5cm q 1.0 cm 0.1-1.9
0.31 (0.22-0.40)
7/40 (18%)
0/40 (0%)
2.0-2.9
0.37 (0.28-0.46)
10/60 (17%)
2/60 (3%)
3.0-3.9
0.54 (0.43-0.65)
12/51 (24%)
5/51 (10%)
4.0-4.9
0.79 (0.58-1.00)
7/38 (18%)
4/38 (11%)
5.0-5.9
0.61 (0.38-0.84)
7/31 (23%)
2/31 (6%)
6.0-6.9
1.21 (0.76-1.66)
7/24 (29%)
3/24 (13%)
Source of Funding: None
THE JOURNAL OF UROLOGY®
METHODS: Data from 278 LPN and 936 OPN were compared. The following variables were retrospectively recorded: surgical indication, tumor size and location, renal vessels clamping and duration, blood loss and transfusions rate, operating time, length of hospital stay, complication rates and pathological data. After matching (1:4) for tumor size, indication and tumor location (hilar vs. peripheral), the data of 137 LPN and 491 OPN were compared. RESULTS: In unmatched analysis, imperative indications (36.3% vs. 10.1%, p=0.0001) and malignant tumors (94% vs. 76.4%, p: 0.0001) were more frequent in the OPN group. In the LPN group, tumors were significantly smaller (2.8 vs. 3.4 cm, p=0.0001), less frequently in hilar location (3.8% vs. 10.4%, p=0.008), blood loss (272 vs. 518 ml, p=0.0001) and transfusion rates (7.7% vs. 13.6%, p=0009) were decreased, as well as length of hospital stay (5.9 vs. 7.6 j, p = 0.0001). By contrast, renal vessels were more often clamped (81.5% vs. 69.9%, p: 0001) for a longer period of time (28.8 vs. 19.7 min, p =0.0001), operating time was increased (156.6 vs. 147.7 min, p: 0.02) and urinary fistulas were more frequent in the LPN group (8.3% vs. 3%, p = 0.0001). In the matched setting, there was no difference between the two groups for transfusion rate (LPN: 6.7% vs. OPN: 8%). Renal vessels clamping data and operating time remained in favour of OPN. Blood loss and length of hospital stay remained in favour of LPN. Medical complication rate was significantly increased in the LPN group (16% vs. 10.4%, p: 0.07).. Despite matching, the occurrence of pT1 stages (OPN: 78% vs. NPL: 87.3%, p = 0.0001) and malignant tumours (NPO: 93.1% vs. NPL: 86.9% p: 0.02) remained significantly different. CONCLUSIONS: This is the first matched comparison between LPN and OPN. By avoiding certain bias but not all it appeared that major advantages and disadvantages of LPN remained after adjusting for surgical indication, tumor size and location. The disadvantages of LPN, particularly length of renal vessels clamping, could disappear in the future thanks to increased experience or emergence of robotic surgery. Source of Funding: None
1317 OUTCOMES OF PARTIAL NEPHRECTOMY FOR CENTRAL AND HILAR (C/H) RENAL MASSES Ross J Mason*, Ricardo A Rendon, Halifax, NS, Canada INTRODUCTION AND OBJECTIVES: Partial nephrectomy (PN) has become the standard of care for the treatment of most renal masses < 4 cm in maximum diameter and for a large portion of renal masses 4 7 cm. With continued advances in surgical techniques, PN has extended to the treatment of masses located centrally within the kidney or close to the renal hilum. This study looked at the association between tumor location and surgical outcomes in patients treated with laparoscopic or open PN at our institution. METHODS: This Institutional Review Board approved study includes 122 patients who underwent laparoscopic or open PN at our institution between January 2002 and July 2008. Clinico-pathological and post-operative data were collected for each patient. Based on pre-operative imaging, each mass was designated as C/H (touching or encroaching upon the collecting system and/or touching the major renal vessels) or peripheral (P). Bivariate logistic regression was used to assess the association between tumor location and surgical margins, and between tumor location and post-operative complications. Secondary analyses were performed to evaluate potential associations between tumor location and other clinical and pathological features. RESULTS: Laparoscopic and open PN were performed on 71(58.2%) and 51(41.8%) patients, respectively. The lesion was located in the C/H and P areas in 67(54.9%) and 55(45.1%) patients, respectively. Mean tumor size was 3.2 cm (range 1.0-7.5 cm). Positive surgical margins were found in 4(6.0%) patients with C/H masses and 4(7.3%) patients with P masses. No association was found between tumor location and positive surgical margins (p=0.773). Post-operative (PO) complications were identified in 16 (23.9%) patients with C/H masses and 13(23.6%) patients with P masses. The effect of tumor location on post-operative complications was not statistically significant (p=0.975). Secondary
Vol. 181, No. 4, Supplement, Tuesday, April 28, 2009
analyses revealed statistically significant associations between tumor location and Fuhrman nuclear grade (p=0.0092) and length of post operative hospital stay (p=0.046). CONCLUSIONS: The results of this study indicate that there is no evidence of an increased risk of identifying positive surgical margins or post-operative complications in patients with C/H vs. P located renal masses who undergo PN. Although more technically challenging, central and hilar renal location should not be a deterrent to performing PN. Source of Funding: None
1318 RADIOLOGIC VS. PATHOLOGIC TUMOR SIZE MEASUREMENTS OF RENAL CELL CARCINOMA: IMPLICATIONS ON RADIO FREQUENCY ABLATION EFFICACY Christopher W Howard*, Samer R Kalakish, Joseph A Pettus, Ashok K Hemal, Kyle A Richards, Victoriano Romero, David D Childs, Ronald J Zagoria, A. Karim Kader, Winston-salem, NC INTRODUCTION AND OBJECTIVES: CT-Guided Radio Frequency Ablation (CT-RFA) has proven to be a safe and, on short term follow-up, reliable treatment modality for renal cell carcinomas (RCCs) with a diameter less than 3.7 cm. However, treatment of tumors with a larger diameter results in an increased risk of recurrence; with each 1 cm increase in tumor diameter over 3.6 cm, the likelihood of tumor-free survival decreases by a factor of 2.19 (p < 0.001). To our knowledge, no studies have compared the measured radiologic size with the pathologic size. Historically, this was not of significant importance due to extirpative surgical resection. However, with CT-RFA it could prove instrumental in achieving complete eradication and improving tumor-free survival, especially for tumors at the upper limit of acceptability for this treatment modality. This study explores the variance between radiologic and pathologic measured size of RCC. METHODS: We retrospectively reviewed 244 cases of surgically resected RCC lesions between the years 2000 and 2008, with CT or MRI sizes of 7.0 centimeters or less that had complete pathologic size information available. RESULTS: We found numerous instances of significant overand under-estimation of size by radiologic methods. The frequency of significant underestimation increases proportional to tumor size. CONCLUSIONS:A discrepancy between radiologic measurement and pathologic measurement of RCC exists and is directly proportional to tumor size. The efficacy of CT-RFA of RCC sharply decreases with tumor sizes greater than 3.7 centimeters. Our data suggests that in some cases the actual tumor diameter may exceed the area targeted for CT-RFA treatment. This warrants an increase in treatment area safety margin proportional to the radiologic size of the tumor. Table 1: Size Discrepancy in Renal Cell Carcinoma Radiologic Size Average Discrepancy Underestimations Underestimations Range (cm) (cm) (95% CI) q 0.5cm q 1.0 cm 0.1-1.9
0.31 (0.22-0.40)
7/40 (18%)
0/40 (0%)
2.0-2.9
0.37 (0.28-0.46)
10/60 (17%)
2/60 (3%)
3.0-3.9
0.54 (0.43-0.65)
12/51 (24%)
5/51 (10%)
4.0-4.9
0.79 (0.58-1.00)
7/38 (18%)
4/38 (11%)
5.0-5.9
0.61 (0.38-0.84)
7/31 (23%)
2/31 (6%)
6.0-6.9
1.21 (0.76-1.66)
7/24 (29%)
3/24 (13%)
Source of Funding: None