Jeman Ryu

Preoperative Factors Predictive of Posterolateral Extracapsular Extension After Radical Prostatectomy

Purpose In radical prostatectomy (RP) procedures, sparing the neurovascular bundles adjacent to the posterolateral aspect of the prostatic fascia has often been suggested as a possible risk factor for positive surgical margins. Here we aimed to quantify the probability of extracapsular extension (ECE) at the posterolateral side of the prostate to aid in nerve-sparing decision making. Materials and Methods We evaluated 472 patients who underwent RP between July 2007 and January 2012. All patients underwent preoperative magnetic resonance imaging (MRI) with diffusion-weighted imaging and apparent diffusion coefficient mapping. We analyzed 944 side-specific prostate lobes with preoperative variables. To quantify the risk of side-specific posterolateral ECE after RP, we developed a risk-stratification scoring system through logistic regression analysis. Results Overall, 20.6% of 944 prostate lobes had ECE. In the multivariate analysis, prostate-specific antigen (PSA), biopsy Gleason score ≥7, percentage of side-specific cores with tumor, and posterolateral ECE on MRI were independent predictive factors of posterolateral ECE. On internal and external validation to calculate the predicted risk, the Hosmer-Lemeshow goodness-of-fit test showed good calibration (p=0.396). Conclusions PSA, biopsy Gleason score, percentage of side-specific cores with tumor, and posterolateral ECE on MRI are independent predictors of posterolateral ECE. The scoring system derived from this study will provide objective parameters for use when deciding if the neurovascular bundle can be safely spared.

Retropubic Versus Robot-Assisted Laparoscopic Prostatectomy for Prostate Cancer: A Comparative Study of Postoperative Complications

PURPOSE To compare the complications of radical retropubic prostatectomy (RRP) with those of robot-assisted laparoscopic prostatectomy (RALP) performed by a single surgeon for the treatment of prostate cancer. MATERIALS AND METHODS The postoperative complications of 341 patients who underwent RRP and 524 patients who underwent RALP for prostate cancer at the Asan Medical Center between July 2007 and August 2012 were retrospectively reviewed and compared. Complications were classified according to the modified Clavien classification system. RESULTS RALP was associated with a shorter length of hospital stay (mean, 7.9 days vs. 10.1 days, p<0.001) and duration of urethral catheterization (6.2 days vs. 7.5 days, p<0.001) than RRP. Major complications (Clavien grade III-IV) were less common in the RALP group than in the RRP group (3.4% vs. 7.6%, p=0.006). There were no significant differences in medical complications between procedures. Considering surgical complications, urinary retention (7.0% vs. 2.7%, p=0.002) and wound repair (4.1% vs. 0.2%, p<0.001) were more common after RRP than after RALP. Extravasation of contrast medium during cystography was more common in the RRP group than in the RALP group (10.0% vs. 2.1%, p<0.001). CONCLUSIONS RALP is associated with a lower complication rate than RRP.

Prognostic factors of oncologic outcomes in metastatic chemotherapy-naïve castration-resistant prostate cancer treated with enzalutamide in actual clinical practice in East Asia

OBJECTIVES We aimed to evaluate the prognostic factors for chemotherapy-naïve castration-resistant prostate cancer (CRPC) treated with enzalutamide in actual clinical practice using easily accessible clinical variables. METHODS AND MATERIALS We retrospectively reviewed the following data from 113 patients with chemotherapy-naïve CRPC treated with enzalutamide: serum levels of prostate-specific antigen (PSA), testosterone, hemoglobin, total protein, albumin, and alkaline phosphatase (ALP); platelet, neutrophil, and lymphocyte counts; neutrophil-to-lymphocyte ratios (NLRs); and liver profiles. PSA progression-free survival (PFS), radiological PFS, and overall survival were estimated by Cox regression analysis. RESULTS Compared with baseline levels, laboratory values at 2 months showed significantly lower PSA (160.2 ± 351.5 ng/ml vs. 47.4 ± 117.1 ng/ml) and ALP levels (201.86 ± 223.77 IU/l vs. 148.25 ± 146.81 IU/l) and a significantly higher percentage of lymphocytes (28.1% ± 10.6% vs. 31.2% ± 9.7%); those at 1 month showed a significantly lower percentage of neutrophils (61.0% ± 11.0% vs. 57.1% ± 12.5%). In the multivariate analysis, poor prognostic factors for PSA PFS were Gleason score ≥ 9 (hazard ratio [HR] 2.022; P = 0.0250); visceral metastasis (HR 3.143; P = 0.0002); high NLR (HR 1.205; P = 0.0126); and high ALP (HR 1.002; P = 0.0015). For radiological PFS, high NLR (HR 1.249; P = 0.0002) and high ALP (HR 1.002; P = 0.0001) were associated with poor outcomes. The predictors of poor overall survival were visceral metastasis (HR 3.155; P < 0.0001); high NLR (HR 1.341; P < 0.0001); and high ALP (HR 1.001; P = 0.0017). CONCLUSION Enzalutamide is less effective in patients with metastatic chemotherapy-naïve CRPC with Gleason scores ≥ 9, visceral metastasis, high NLR, and high ALP.

Factors associated with testosterone recovery after androgen deprivation therapy in patients with prostate cancer

Purpose We investigated factors affecting testosterone recovery after androgen deprivation therapy (ADT) withdrawal in patients with prostate cancer. Materials and Methods The medical records of patients who underwent radical prostatectomy with ADT were retrospectively reviewed. In all, 221 patients were included in the analysis. Testosterone recovery was defined as supra-castration (SC) (testosterone levels in serum >50 ng/dL) or out of hypogonadism (OH) (>300 ng/dL) after ADT withdrawal. Kaplan-Meier analyses were used to estimate testosterone recovery after ADT cessation. Cox regression analyses were used to determine the factors affecting the recovery of testosterone. Results After ADT, 206 patients (93.2%) recovered to the SC level and 122 patients (55.2%) recovered to the OH level. Patients treated with ADT for ≤18 months recovered to OH in a mean of 6.8 months (74.6%), but patients treated with ADT for >18 months recovered in a mean of 9.7 months (27.5%). In multivariate analyses, age (hazard ratio [HR], 0.915; p<0.001), serum level of sex hormone-binding globulin (SHBG) (HR, 1.015; p=0.002), initial testosterone level (HR, 1.002; p=0.002), and ADT duration (HR, 0.915; p<0.001) were associated with recovery to the OH level after ADT withdrawal, and hypertension (HR, 0.697; p=0.029) and duration of ADT (HR, 0.979; p=0.012) were significantly associated with recovery to SC. Conclusions In patients treated with ADT for ≤18 months, testosterone recovers to the OH level more often and faster after ADT cessation. Age, SHBG level, initial testosterone level, and ADT duration are associated with testosterone recovery.

Simple risk assessment in prostate cancer patients treated with primary androgen deprivation therapy: The Korean Cancer Study of the Prostate risk classification

To investigate the progression to castration‐resistant prostate cancer after primary androgen deprivation therapy, and to build a simple risk prediction model for primary androgen deprivation therapy patients based on the Japan Cancer of the Prostate Risk Assessment criteria.

MP55-03 DOES HISTOLOGY SUBTYPE NEED TO BE CONSIDERED AFTER PARTIAL NEPHRECTOMY IN PATIENTS WITH PATHOLOGIC T1A RENAL CELL CARCINOMA?: PAPILLARY VS. CLEAR CELL RENAL CELL CARCINOMA

Purpose We compared the oncological outcomes of papillary renal cell carcinoma (pRCC) with clear cell renal cell carcinoma (ccRCC) after partial nephrectomy (PN) in patients with pathologic T1a RCC.

MP16-16 IS THERE ANY DIFFERENCE IN PROGNOSIS BETWEEN SYNCHRONOUS AND METACHRONOUS BRAIN METASTASIS FROM METASTATIC RENAL CELL CARCINOMA?

INTRODUCTION AND OBJECTIVES: The prognosis of renal cell carcinoma (RCC) brain metastasis (BM) is relatively poor. We evaluated the oncological outcomes of synchronous and metachronous BM of metastatic RCC according to local or systemic therapy. METHODS: Metastatic RCC patients (n1⁄493) with synchronous and metachronous BM were retrospectively identified. We analyzed patients and tumor characteristics, treatment method, prognostic factors, BM progression and overall survival (OS). Synchronous BM was compared with metachronous BM using multivariable Cox regression. RESULTS: 76 patients (81.7%) received local therapy (stereotactic radiosurgery [60.0%], radiation therapy [23.5%], neurosurgery [10.1%]) and 54 patients (58.1%) were treated with systemic medical therapy. Median OS after diagnosis of BM were 9.2 months. In multivariable analysis, sarcomatoid component (hazard ratio [HR] 2.807, 95% confidence interval [CI] 1.088-7.239, p1⁄40.0328) and multiple BM (HR 3.177 95% CI 1.561-6.469, p1⁄40.0014) were significant factors for BM progression. MSKCC poor risk (HR 3.672, 95% CI 1.441-9.36, p1⁄40.0064), sarcomatoid component (HR 4.264, 95% CI 2.062-8.820, p1⁄40.0001) and multiple BM (HR 2.838, 95% CI 1.690-4.767, p1⁄40.0001) were prognostic factors for worse OS. In addition, local treatment (HR 0.436, 95% CI 0.237-0.802, p1⁄40.0076) and systemic treatment (HR 0.322, 95% CI 0.190-0.548, p<0.0001) were also independent factors for better OS. Although the OS from initial RCC diagnosis in metachronous BM patients was longer than synchronous BM patients, there was no difference between synchronous and metachronous in BM progression and OS after diagnosis of brain metastasis. CONCLUSIONS: MSKCC poor risk, sarcomatoid component of histology, and multiple BM were poor prognostic factors for OS. Systemic or local treatment improved OS, but the type of synchronous and metachronous BM did not influence BM progression and OS.

MP59-09 FUNCTIONAL CHANGE OF CONTRALATERAL KIDNEY AFTER PARTIAL NEPHRECTOMY USING DIETHYLENE TRIAMINE PENTA-ACETIC ACID (DTPA) RENAL SCINTIGRAPHY: LONG TERM ANALYSIS

INTRODUCTION AND OBJECTIVES: Partial nephrectomy aims to maintain renal function by nephron sparing. However, the functional change of contralateral kidney remains to be known. We evaluated the functional change in contralateral kidney using DTPA renal scan and determined the predicting factors of contralateral kidney function after partial nephrectomy. METHODS: From 2001 to 2012, 699 patients underwent partial nephrectomy and we performed DTPA renal scan before and after surgery in all patients to assess the exact renal function of each kidney. Patients were divided into 3 groups according to initial contralateral glomerular filtration rate (GFR) (group 1: <30ml/min/1.73m2, group 2: 30~45ml/min/1.73m2, and group 3: 45ml/min/1.73m2). We evaluated separate renal functions using DTPA up to 5 year after surgery. Logistic regression analysis was used to identify the factors associated with increased GFR of contralateral kidney. Kaplan-Meier method was used for overall survival. Median follow-up period was 45.1 month. RESULTS: Patients of group 1 were older age (64.2 9.8 vs 55.0 11.0 vs 48.0 9.5, p<0.001), more hypertension history (59.5% vs 39.3% vs 20.9%, p<0.001), worse American society of anesthesiologists (ASA) score ( 2; 94.0% vs 89.5% vs 80.2%, p<0.001), and shorter ischemic time (19.9 8.0 vs 22.3 8.7 vs 22.8 8.9, p1⁄40.025) among three groups (respectively). Tumor size, resected weight, RENAL nephrometry score and ischemic type were not different among three groups (p1⁄40.293, p1⁄40.255, p1⁄40.582 and p1⁄40.967, respectively). The mean ipsilateral GFR changes were -7.5%, -1.6%, and -21.2% in group 1, 2, and 3, respectively and contralateral GFR changes were 33.9%, 19.9%, and 7.3% in group 1, 2, and 3, respectively at 5 year after partial nephrectomy. On multivariable analysis, ASA score (OR 0.54, 95% confidence interval [CI] 0.31-0.92 p1⁄40.0277) and preoperative contralateral GFR (OR 0.97, 95% CI 0.95-0.99 p1⁄40.0011) were the significant predictive factors for increased GFR of contralateral kidney within 5 years. 5 year overall survival rates were 86.1%, 93.1% and 97.4% in group 1, 2, 3, respectively. CONCLUSIONS: Contralateral kidney compensated for the functional loss of ipsilateral kidney. The increase of GFR in contralateral kidney is more prominent in healthy patients with decreased contralateral renal function.

MP55-02 IMPACT OF NECROTIC AND SARCOMATOID COMPONENTS ON ONCOLOGICAL OUTCOMES IN PATIENTS WITH NON-METASTATIC RENAL CELL CARCINOMA

INTRODUCTION AND OBJECTIVES: In 2016 the World Health Organization coined the term mixed epithelial and stromal tumor family (MESTF) to encompass adult cystic nephroma (ACN) within the classification of mixed epithelial and stromal tumors (MESTs) on the basis of overlapping clinical and pathologic profiles. MESTs have traditionally been regarded as benign, with only a few reports of malignant transformation or recurrence in the literature. Diagnosis requires histopathological evaluation, as radiologic imaging cannot accurately determine whether such tumors are benign or malignant. We aim to characterize our institutional experience with this rare neoplasm. METHODS: We identified all patients with a pathological diagnosis of MEST or ACN from our prospectively collected institutional database between Jan 1995 Dec 2015. Available imaging was rereviewed by a single expert radiologist (AH). Demographic, radiologic, and clinical characteristics were recorded. RESULTS: Data was available for 40 patients. The median age at diagnosis was 48.8 years (31.5-73.4). Thirty-seven (92.5%) patients were female and three (7.5%) were male. Imaging was available for rereview for 29 (72.5%) patients. The mean diameter of the tumor on preoperative imaging was 5.8 cm (1.9-16.1). Patients presenting with symptoms at diagnosis had a mean diameter of 7.4 cm (4-16.1). On imaging, 25 (86.2%) tumors where characterized as Bosniak 3 lesions and four (13.8%) were described as Bosniak 4 lesions. All patients underwent surgical resection, with partial nephrectomy performed in 72.5% of cases. Mean pathological tumor size was 5.9 cm (1.5-15). Median follow-up was 71.6 months (1-217). Two (4.9%) patients died from non-tumor related causes. At last follow-up, all patients showed no evidence of disease. CONCLUSIONS: MESTF are indolent tumors with a female predominance. They are usually detected incidentally as Bosniak 3 or 4 lesions. Partial nephrectomy should be performed whenever possible to resect the tumor and preserve renal function. Given the low likelihood of recurrence following excision, we believe that, once pathologically identified, patients have an excellent long-term prognosis and require minimal surveillance imaging on follow-up. Genomic characterization is currently underway. Source of Funding: Funded in part by the Sidney Kimmel Center for Prostate and Urologic Cancers and the National Cancer Institute Training Grant T32 CA082088 (BM, MG)