Sho Uehara

Stepwise algorithm using computed tomography and magnetic resonance imaging for diagnosis of fat-poor angiomyolipoma in small renal masses: Development and external validation

To develop a stepwise diagnostic algorithm for fat‐poor angiomyolipoma in small renal masses.

Prediction of Intraoperative Urinary Collecting System Entry in Patients with Peripheral Renal Tumors Undergoing Partial Nephrectomy: Usefulness of Tumor-Centered Multiplanar Reconstruction

Objective: To assess the usefulness of tumor-centered multiplanar reconstruction (TC-MPR) for predicting intraoperative urinary collecting system (UCS) entry in patients with peripheral renal tumors undergoing partial nephrectomy (PN). Methods: Dynamic computed tomography images of 50 peripheral cT1 renal tumors treated with laparoendoscopic PN were analyzed. TC-MPR generated a digital cross-sectional image showing the tumor center and the closest calyx on a same plane. Patients and tumor characteristics including the distance from the tumor margin to the closest calyx (MPR-distance), and the angle formed by 2 tangent lines from the closest calyx to the tumor (MPR-angle) were assessed. Results: Intraoperative UCS entry was observed in 15 patients (30%). The patients who experienced intraoperative UCS entry had a higher RENAL score, wider MPR-angle, and shorter MPR-distance than those who did not (p = 0.04, p = 0.001, p < 0.001, respectively). Multivariate analysis identified MPR-angle as an independent factor for intraoperative UCS entry (p < 0.001). Conclusions: The spatial information assessed using TC-MPR serves as a predictive factor for intraoperative UCS entry during PN.

MP16-06 EARLY RESPONSE AT FOUR WEEKS OF C-REACTIVE PROTEIN PREDICTS SURVIVAL IN PATIENTS WITH METASTATIC RENAL CELL CARCINOMA TREATED WITH TYROSINE KINASE INHIBITORS

INTRODUCTION AND OBJECTIVES: It remains the standard approach for assessing the prognosis of mRCC patients treated with molecular-targeted agents to use the MSKCC and IMDC risk classifications, while the significant prognostic impact of the objective tumor response to these novel agents in mRCC patients has recently been documented in various studies. We also reported that the overall survival (OS) in patients with mRCC was closely correlated with the degree of tumor shrinkage at 12 weeks after the introduction of first-line targeted agents (Target Oncol 2016; 11: 175-82). Of these, however, there was no study focusing on data from mRCC patients treated with second-line targeted agents outside clinical trials. The objective of this study was to evaluate the impact of early tumor shrinkage (ETS) induced by a second-line targeted agent on OS in mRCC patients. METHODS: This study retrospectively included 271 consecutive Japanese patients with mRCC who received second-line targeted therapy for at least 3 months. ETS was defined as the degree of tumor shrinkage at the first post-baseline radiological evaluation conducted 4 to 8 weeks after initiating second-line targeted therapy. RESULTS: Of the 271 patients, 26 had ETS from -100 to -50%, 70 from -49 to -25%, 84 from -24 to 0%, and the remaining 91 failed to achieve a reduction in the tumor size. The median OS following the initiation of second-line targeted therapy stratified according to ETS was 45.8, 30.9, 22.1 and 14.2 months, respectively. Univariate analysis identified prior nephrectomy, the MSKCC risk classification, C-reactive protein (CRP) level, number of metastatic organs, sarcomatoid feature, introduced second-line agent and ETS induced by a second-line agent as parameters significantly associated with OS, of which, only the MSKCC classification, CRP level and ETS appeared to have independent impacts on OS on multivariate analysis. CONCLUSIONS: Collectively, these findings suggest that ETS at the first post-baseline assessment under treatment with a second-line targeted agent could serve as a useful parameter with an independent impact on OS in mRCC patients receiving second-line targeted therapy; therefore, it is highly recommended to select second-line targeted agents that make it possible to induce prompt tumor remission to further improve the prognosis of patients with mRCC following the failure of first-line targeted therapy.

PD14-06 DEVELOPMENT AND VALIDATION OF A NOVEL STEPWISE ALGORITHM USING CT AND MRI FOR DIAGNOSIS OF FAT-POOR ANGIOMYOLIPOMA IN SMALL RENAL MASSES

imaging technique used for the rapid histological diagnosis of renal cell carcinoma on percutaneous biopsy. METHODS: After institutional board approval, 50 total percutaneous biopsieswere obtained from20 patients undergoing either partial or radical nephrectomy from resected renal tissue after specimen removal. Biopsy specimens were sprayed with a dual topical fluorescent stain, and VR-SIM images obtained using a 4.2 megapixel, high-speed CMOS camera with fast ferroelectric spatial light modulators. Biopsy specimens were subsequently fixed and analyzed using standard hematoxylin and eosin (H&E) histopathologic methods. One blinded pathologist reviewed all VR-SIM images and H&E specimens. The presence of cancer was correlated between the twomodalities and final standard pathology result. RESULTS: Of the 50 biopsy specimens, fourteen were determined to be malignant on H&E, while 36 represented benign renal tissue. Thirteen of the 14 malignant specimens were diagnosed by VRSIM, with 1 specimen being assessed as indeterminant. Sensitivity and specificity of VR-SIM were 93% and 100%, respectively. CONCLUSIONS: VR-SIM is a promising and practical method for point of care renal biopsy assessment. This may translate into the ability to rapidly assess sufficiency of biopsy specimens and enable immediate diagnostic capability to aid in counseling patients regarding management options.

Long-term complete response of antiandrogen withdrawal syndrome in a patient with metastatic prostate cancer: A case report

Antiandrogen withdrawal syndrome (AWS) is a well-established phenomenon in prostate cancer treated with combined androgen blockade (CAB). AWS is generally defined as subjective and/or objective improvement following discontinuation of an antiandrogen. However, the duration of the AWS response is usually limited. In addition, a complete response is quite rare. We herein present the case of a patient who achieved complete response from AWS, with the duration of this response lasting for >6 years. A 72-year-old man with metastatic prostate cancer received CAB with a luteinizing hormone-releasing hormone analog and bicalutamide. In addition, for local cancer control, external beam radiation therapy (70 Gy) to the prostate was performed. Subsequently, the serum prostate-specific antigen (PSA) level reached a nadir (undetectable level). Four years later, the patients serum PSA level started to rise, and bicalutamide was discontinued to confirm AWS at a serum PSA level of 0.34 ng/ml. The PSA level immediately decreased again to an undetectable level (0.00 ng/ml), where it has been remained for 6 years. Bone scintigraphy and computed tomography scans have shown no evidence of bone or other metastases since the introduction of AWS. To the best of our knowledge, there have been no reports of such a long duration of complete response from AWS. Therefore, this phenomenon should always be considered, even in patients with advanced disease.