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.