Primary Robot-assisted Retroperitoneal Lymph Node Dissection for Men with Nonseminomatous Germ Cell Tumor: Experience from a Multi-institutional Cohort.

BACKGROUND: Primary robot-assisted retroperitoneal lymph node dissection (RA-RPLND) for men with nonseminomatous germ cell tumor (NSGCT) is an alternative to open RPLND for stage I and select stage II patients. OBJECTIVE: To report the complication rates and oncologic outcomes from a multi-institutional series, and to estimate reduction in chemotherapy by using upfront minimally invasive surgery. DESIGN, SETTING, AND PARTICIPANTS: A retrospective chart review of men undergoing primary robot-assisted RPLND between 2014 and 2019 in five institutions by eight urologists experienced in testis cancer and robotic surgery. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Variables such as demographic and clinicopathologic information, operative parameters and complication rates, oncologic outcomes, sexual recovery, and hospital length of stay were collected. Descriptive statistics are presented. RESULTS AND LIMITATIONS: Forty-nine patients were analyzed with a median follow-up of 15.0 mo (interquartile range 6.5-29.1 mo). Median operative time was 288 min, estimated blood loss was 100 ml, and lymph node yield was 32. Median length of stay was 1 d. There were nine postoperative complications, 44% (4/9) of which were Clavien grade 1. There were no Clavien grade IV complications. Twenty-one patients had metastatic NSGCT (42.8%), of whom nine (18.4%) received adjuvant chemotherapy. Four patients experienced recurrence (three out-of-field and one in-field recurrence). Limitations include the retrospective study design and various surgical techniques among surgeons. CONCLUSIONS: Primary robot-assisted RPLND for NSGCT can be performed safely, with low complication rates and acceptable oncologic outcomes reducing the need for chemotherapy. For a population in which compliance with surveillance is typically challenging, robot-assisted RPLND may improve quality of care and outcomes for patients with NSGCT. PATIENT SUMMARY: In experienced centers, robot-assisted retroperitoneal lymph node dissection can be performed safely with similar oncologic outcomes to an open approach, while providing an option that may reduce the need for chemotherapy.

Primary Renal Lymphoma Identified in a Robot-Assisted Laparoscopic Nephroureterectomy Specimen.

BACKGROUND: Although renal involvement is often present in non-Hodgkin's lymphoma (NHL), primary renal NHL is a rare diagnosis. CASE PRESENTATION: We present a case report of a 72-year-old asymptomatic male who underwent a robot-assisted laparoscopic radical nephroureterectomy on an atrophic left kidney with evidence of an infiltrating mass. Pathology report demonstrated a grade 1 follicular lymphoma. CONCLUSION: Lymphoma is a differential that should be considered when evaluating a renal mass. Chemotherapy and radiation are the mainstays of treatment.

Two Unexpected Tumors in a Laparoscopic Nephrectomy Specimen, Including a Rare Tubulocystic Renal-Cell Carcinoma: A Case Report.

We present a case of a 52-year-old Caucasian male who underwent a laparoscopic nephrectomy for an atrophic kidney and was found to have two unexpected, synchronous kidney cancers. He had a remote history of testicular cancer complicated by lymphadenopathy and external ureteral compression. Over time, he developed an atrophic left kidney from obstructive uropathy. Years later, due to flank pain and renal scintigraphy showing minimal function, a laparoscopic nephrectomy was performed. Final pathology demonstrated papillary renal-cell carcinoma (RCC) and tubulocystic RCC. Tubulocystic RCC is a rare neoplasm thought to be an indolent subset of collecting duct carcinoma, but was identified as a unique entity in 2004. Currently, there are ∼100 cases of this neoplasm in the literature.

Residues required for activity in Escherichia coli o-succinylbenzoate synthase (OSBS) are not conserved in all OSBS enzymes.

Understanding how enzyme specificity evolves will provide guiding principles for protein engineering and function prediction. The o-succinylbenzoate synthase (OSBS) family is an excellent model system for elucidating these principles because it has many highly divergent amino acid sequences that are <20% identical, and some members have evolved a second function. The OSBS family belongs to the enolase superfamily, members of which use a set of conserved residues to catalyze a wide variety of reactions. These residues are the only conserved residues in the OSBS family, so they are not sufficient to determine reaction specificity. Some enzymes in the OSBS family catalyze another reaction, N-succinylamino acid racemization (NSAR). NSARs cannot be segregated into a separate family because their sequences are highly similar to those of known OSBSs, and many of them have both OSBS and NSAR activities. To determine how such divergent enzymes can catalyze the same reaction and how NSAR activity evolved, we divided the OSBS family into subfamilies and compared the divergence of their active site residues. Correlating sequence conservation with the effects of mutations in Escherichia coli OSBS identified two nonconserved residues (R159 and G288) at which mutations decrease efficiency ≥200-fold. These residues are not conserved in the subfamily that includes NSAR enzymes. The OSBS/NSAR subfamily binds the substrate in a different orientation, eliminating selective pressure to retain arginine and glycine at these positions. This supports the hypothesis that specificity-determining residues have diverged in the OSBS family and provides insight into the sequence changes required for the evolution of NSAR activity.