Perioperative outcomes and cost of robotic vs open simple prostatectomy in the modern robotic era: results from the National Inpatient Sample

OBJECTIVES

To perform a comparative analysis of perioperative outcomes and hospitalisation cost between open (OSP) and robot-assisted simple prostatectomy (RASP) for treatment of benign prostatic hyperplasia (BPH) using the National Inpatient Sample (NIS) in the contemporary robotic era.

MATERIALS AND METHODS

The NIS was queried for cases of OSP and RASP for the treatment of BPH between 2013 and 2016. Perioperative complications, unadjusted hospital cost and length of stay (LOS) were compared between RASP and OSP. Smoothed linear regression curves comparing hospitalisation cost by increasing LOS was stratified by surgical approach to identify point of cost equivalency between RASP and OSP. Multivariable linear regression analysis was used to construct a hospitalisation cost model to examine the contribution of the robotic approach and LOS to hospitalisation cost.

RESULTS

The total analytical cohort included 2551 OSP and 704 RASP procedures. Patients undergoing RASP were younger, at a median (interquartile range [IQR]) age of 68 (63-73) vs 71 (65-77) years, and with less comorbidity (76.8% vs 86.5%, P < 0.01). RASP was associated with fewer total complications (11.1% vs 29.2%, P < 0.01) and a greater likelihood of routine discharge to home rather than another facility (88.9% vs 76.7%, P < 0.01). While LOS was shorter with RASP (median [IQR], 2 [1-3] vs 4 [3-6] days, P < 0.01), total unadjusted hospitalisation cost (in United States dollars) was greater (median [IQR], $10 855 [$7965-$15 675] vs $13 467 [$10 572-$17 722], P < 0.01). Presence of any complication increased both LOS and hospitalisation cost (P < 0.01). Linear regression modelling determined the point of cost equivalence between RASP staying a median of 2 days was an OSP case staying between 5 and 6 days. On multivariable regression analysis, the robotic approach contributed an additional $6175 (P < 0.01) to the cost model, whereas each additional day of hospitalisation contributed $1687 (P < 0.01), suggesting LOS would need to be 3-4 days shorter with RASP to offset surgical costs of the robot.

CONCLUSIONS

While RASP appears to have significantly better perioperative complication rates with shorter LOS and likely discharge to home, total hospitalisation cost remained greater, likely related to upfront operative costs. While this retrospective study is limited by selection bias for patients undergoing RASP, the benefits of improved convalescence, discharge to home, and lower rate of perioperative complications appear to justify performance of RASP in an experienced pelvic robotic centre despite relatively greater hospitalisation cost if referral to an experienced holmium laser enucleation of the prostate centre is not feasible.

Population-based analysis of cost and peri-operative outcomes between open and robotic primary retroperitoneal lymph node dissection for germ cell tumors

PURPOSE

To compare perioperative outcomes and perform the first cost analysis between open retroperitoneal lymph node dissection (O-RPLND) and Robotic-RPLND (R-RPLND) using a national all-payer inpatient care database.

METHODS

Nationwide Inpatient Sample (NIS) was queried between 2013-2016 for primary RPLND and germ cell tumor. We compared cost, length of stay (LOS), and complications between O-RPLND and R-RPLND. Linear regression plots identified point of cost equivalence between R-RPLND and O-RPLND. A multivariable linear regression model was generated to analyze predictors of cost.

RESULTS

44 cases of R-RPLND and 319 cases of O-RPLND were identified. R-RPLND was associated with lower rate of complications (0% vs. 16.6%, p < 0.01) and shorter LOS [Median (IQR): 1.5 (1-3) days vs. 4 (3-6) days, p < 0.01]. Rates of ileus, genitourinary complications, and transfusions were lower with R-RPLND, but did not reach significance. On multivariable analysis, robotic approach independently contributed $4457, while each day of hospitalization contributed to an additional $2,431 to the overall model of cost. Linear regression plots determined point of cost equivalence between an R-RPLND staying a mean of 2 days was 4-5 days for O-RPLND, supporting the multivariable analysis. Total hospitalization cost was equivalent between R-RPLND and O-RPLND [Median (IQR): $15,681($12,735-$21,596) vs $16,718($11,799-$24,403), p = 0.48]-suggesting that the cost equivalency of R-RPLND is, at least in part, attributable to shorter LOS.

CONCLUSION

While O-RPLND remains the gold standard and this study is limited by selection bias of a robotic approach to RPLND, our findings suggest primary R-RPLND may represent a cost-equivalent option with decreased hospital LOS in select cases.

Nationwide Patterns of Care for Stage II Nonseminomatous Germ Cell Tumor of the Testicle

BACKGROUND

Management strategies for advanced testicular cancer published from a few, high-volume clinical centers may not be generalizable.

OBJECTIVE

To discern treatment patterns for stage II nonseminomatous germ cell tumor (NSGCT) in a nationwide cancer registry.

DESIGN, SETTING, AND PARTICIPANTS

The National Cancer Database was queried for patients with a stage II NSGCT from 2004 to 2014. Patients were stratified by clinical nodal status: cN1/stage IIA, cN2/stage IIB, and cN3/stage IIIC.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

Logistic regression was performed to determine factors independently associated with primary retroperitoneal lymph node dissection (RPLND), primary chemotherapy, and postchemotherapy RPLND (PC-RPLND).

RESULTS AND LIMITATIONS

A total of 2203 patients (stages IIA, n=1060; IIB, n=869; and IIC, n=274) met the inclusion criteria. Overall, 83% of patients underwent primary chemotherapy, while 17% underwent primary RPLND. Stratified by stage, use of primary chemotherapy was 78%, 88%, and 86% for stages IIA, IIB, and IIC, respectively. Overall, 24% of patients underwent PC-RPLND. Factors independently associated with a lower likelihood of undergoing primary RPLND were a more recent diagnosis and a higher clinical nodal stage. Conversely, patients treated at high-volume facilities were more likely to receive primary RPLND. Factors associated with a higher likelihood of undergoing PC-RPLND included a higher clinical nodal stage, treatment at a high-volume center, and a greater distance of patient travel. Associations based on serum tumor markers could not be assessed.

CONCLUSIONS

For clinical stage II NSGCT, nationwide utilization of primary chemotherapy is increasing compared with RPLND and is the preferred therapy for more advanced nodal disease. Primary RPLND may be underutilized in stage IIA disease. Utilization of PC-RPLND is driven by nodal stage as well as accessibility of a high-volume center.

PATIENT SUMMARY

The use of primary retroperitoneal lymph node dissection (RPLND) in early nodal disease is declining, while upfront chemotherapy is increasingly utilized. Primary RPLND may identify patients who are actually pN0 and would not benefit from systemic chemotherapy. Primary RPLND and postchemotherapy RPLND are performed more frequently at centers of excellence.

A fluorescence study of the binding of poly(1,N6-ethenoadenylic acid) to Escherichia coli initiation factor 3

The binding of initiation Factor 3 (IF3) to poly (1,N6-ethenoadenylic acid) [poly(epsilon A)] was investigated by fluorescence spectroscopy. At low salt concentrations, IF3 evokes an increase in the fluorescence intensity of poly(epsilon A) due to the unstacking of the nucleotide bases. The poly(epsilon A) fluorescence enhancement titrates to an endpoint of 13 +/- 2 nucleotide residues per IF3. The maximum poly(epsilon A) fluorescence enhancement, at lattice saturation, decreases with increasing salt concentration. Even though IF3 does not produce a large fluorescence increase between 75 and 200 mM NaCl concentration, the protein still binds to poly(epsilon A) at these salt concentrations as measured by sedimentation partition chromatography; the value of Kobs for the IF3-poly(epsilon A) interaction is comparable to that of other synthetic polynucleotides. The binding of IF3 to poly(A) at 150 and 200 mM NaCl induces an increase in nucleotide base-base separation as determined by CD, yet IF3-induced disruption of base stacking of poly(epsilon A) at these same salt concentrations is not detected by fluorescence. It is likely that IF3 binds primarily to the phosphate backbone of poly(epsilon A) at low salt concentrations, producing an increase in the fluorescence intensity. But, at higher salt concentrations, the aromatic amino acids intercalate between the nucleotide bases quenching the poly(epsilon A) fluorescence.