Abstracts from the New England Section of the AUA 2021

© The Canadian Journal of Urology TM : International Supplement, October 2021 Concurrent Poster Session II Lessons Learned from an Early Experience with Robotic Radical Nephrectomy and IVC Thrombectomy Da David Jiang, MS, MD, MJ Counsilman, MD , Alejandro Abello, MD, Allison Kleeman, BS, Adrian Waisman, MD, Catrina Crociani, MS, Boris Gershman, MD, Peter Chang, MD, Andrew A. Wagner, MD Beth Israel Deaconess Medical Center, Boston, MA, USA Introduction: Radical nephrectomy with inferior vena cava (IVC) thrombectomy remains a challenging and high risk surgery. This procedure is typically approached through a large chevron, thoracoabdominal, or midline incision, resulting in significant morbidity. In an effort to improve convalescence and lower complications, efforts have been made to remove the tumor thrombus and reconstruct the IVC robotically. We present our single institution experience with robotic radical nephrectomy with IVC thrombectomy as well as a video illustration of our technique. Materials &Methods: All robotic IVC thrombectomy cases were performed by a fellowship-trained urology attending. Patients were positioned in a modified lateral position. For the left sided case, the nephrectomy portion was performed as a pure laparoscopic nephrectomy and the patient was then re-positioned for robotic IVC thrombectomy. Regional lymphadectomy was performed on all patients. The ipsilateral adrenal gland was removed in all but one patient. Results: A total of 6 patients underwent robotic radical nephrectomy with level one tumor thrombectomy (into the IVC but <2cm above renal vein) between 2015 and 2021. The median follow up was 25 months (range 1-32). Patient demographics and perioperative outcomes are highlighted in the table. All patients had ECOG score of 0. Two patients had clinically enlarged regional nodes; and 2 patients presented with metastatic disease. Median operative time was 4.2 hrs (range 3.1-6.3). Median estimated blood loss (EBL) was 300mL (range 100-750) and the median hospital stay was 2.5 days (range 2-12). We performed complete IVC control using laparoscopic bulldog clamps in all patients and IVC repair was performed with either 5-0 prolene or 5-0 Gore-tex running sutures. One patient required IVC reconstruction using a bovine pericardial patch. There were no intraoperative transfusions or open conversions. The positive margin rate at the vein edge was 67%. One patient with a clinically enlarged regional lymph node had pathologically node positive disease. There was one diaphragmatic injury intraoperatively which was primarily repaired without issues. There was one postoperative 90-day complication: the first patient in our series experienced a postoperative bleed from a dislodged hemolock clip on a lumbar vein, requiring open surgical exploration 6 hours postop. Two patients had metastatic disease on presentation; they both received adjuvant systemic therapy and ultimately succumbed to their disease. Of patients who did not have metastatic disease on presentation (n=4), one patient (25%) has a recurrence in his lung and received radiation to this area, the median recurrence free survival is 12 months (range 1-38). Conclusions: Robotic radical nephrectomy for level one IVC thrombus in experienced hands is safe with a low incidence of perioperative complications and relatively short convalescence. Sestamibi SPECT CT for Indeterminate Renal Lesions: A Single Center Experience Alison Levy, MD , Esther Finney, MD, Yamin Dou, MD, Andrea Sorcini, MD, David Canes, MD Lahey Hospital, Burlington, MA, USA Introduction : Incidentally discovered small renal masses are a heterogeneous group, spanning a spectrum from benign histology to indolent malignancies to aggressive phenotypes. Renal mass biopsy is warranted when the result would alter management, but the procedure is not without morbidity, and the non-diagnostic rate is 8-14%. Dual goals are to treat potentially threatening tumors, and to leave indolent or benign tumors untreated. Tc99m-Sestamibi SPECT/CT may help differentiate benign from malignant lesions, based on high density of mitochondria in oncocytomas and hybrid oncocytoma/ chromophobe tumors. We present a single center experience with this technology for indeterminate renal masses. Materials & Methods: Our institutional radiologic database was queried for patients who underwent Tc99m-Sestamibi SPECT/CT for classification of indeterminate renal masses. Lesion uptake was compared to surrounding renal parenchyma and classified as increased or no uptake. Charts were reviewed retrospectively for patient demographics and tumor characteristics. Results: A total of 7 lesions were identified for which Tc99m-Sestamibi SPECT/CT was performed between 2020-2021. Five of seven lesions had increased radiotracer uptake, consistent with oncocytoma or oncocytic neoplasm. They all underwent biopsy as well, with pathology suggestive of oncocytic neoplasm. Patients with these “hot” lesions on Sestamibi scan all remain on active surveillance. Two tumors were “cold” on Sestamibi, without radiotracer uptake. One underwent robotic-assisted laparoscopic partial nephrectomy. Final pathology demonstrated a cT1a chromophobe carcinoma with prominent eosinophils, a known scenario that could be considered a misleading Sestamibi SPECT/ CT result, given the tumor’s indolent nature. The other patient is scheduled for an upcoming open partial nephrectomy. Conclusions: Although Sestamibi SPECT/CT has yet to be featured as part of the AUAguideline algorithm for renal mass management, we find it to be a useful tool for select patients with indeterminate renal masses to support surveillance in those with “hot” lesions, or to bolster the decision to proceed with surgery in those with “cold” lesions suggestive of malignancy. Although our sample size is small, we hope that highlighting this imaging modality brings further awareness to its utility. P22 P21 46