Date Published: May 3, 2018
Author(s): Zeyad R. Schwen, Mohit Gupta, Phillip M. Pierorazio.
The robotic-assisted laparoscopic retroperitoneal lymph node dissection (R-RPLND) represents a new frontier in the surgical management of testicular cancer in the realm of minimally invasive urologic oncology. We aimed to review the early outcomes as compared to the laparoscopic and open approaches as well as describe the operative technique for the R-RPLND.
We reviewed all the literature related to the R-RPLND based on an electronic PubMed search up until July 2017.
Encouraged by favorable early oncologic and safety outcomes for treatment of clinical stage (CS) I nonseminomatous germ cell tumor (NSGCT), the R-RPLND affords the same recovery advantages as the laparoscopic retroperitoneal lymph node dissection (L-RPLND) while offering greater dexterity, superior visualization, and a theoretically shorter learning curve for the surgeon. While R-RPLND has a promising future in the management of patients with primary and postchemotherapy NSGCT, larger and more vigorous prospective studies are needed before supplanting the open RPLND as the gold standard approach for primary low-stage NSGCT or becoming an equivalent surgical modality in the postchemotherapy setting.
Testicular germ cell tumor (GCT) is the most common solid tumor in men between the ages of 20–44. Men diagnosed with GCT have excellent survival rates due to advances in the multimodal treatment paradigm of chemotherapy, radiation therapy, and surgery . Retroperitoneal lymph node dissection (RPLND) remains an established treatment option for nonseminomatous GCT in the primary setting for low-stage (clinical stages (CSs) I and II) diseases and residual masses after chemotherapy . Due to the excellent survival outcome, with a 5-year overall survival rate of 98%, there has been a greater emphasis on reducing morbidity and long-term toxicity for testicular cancer survivors. Open RPLND (O-RPLND) remains the gold standard approach for surgical management of the retroperitoneum for GCTs. It is, however, maximally invasive and can result in significant postoperative morbidity and prolonged hospitalizations [2–4].
We performed an electronic PubMed search for all relevant publications regarding the outcomes and technique of the R-RPLND up until July 2017. We used the keywords robotic, retroperitoneal lymph node dissection, and testicular cancer, which resulted a total of 36 papers. All single and multi-institutional R-RPLND studies in adults with testicular cancer were included and reviewed in addition to studies investigating outcomes associated with O-RPLND and L-RPLND.
Postchemotherapy RPLND (PC-RPLND) for patients with residual tumors after chemotherapy represents a far more challenging surgery compared to the primary RPLND setting. Desmoplasia from the therapeutic action of chemotherapy can fuse normal tissue planes and add complexity to dissection of tissues and, if needed, repair of vascular injuries. The risk-benefit ratio of cancer cure and morbidity of surgery makes justification of an investigational, minimally invasive technique more challenging. However, select surgeons and centers report perioperative outcomes supporting minimally invasive PC-RPLND as a safe surgery. In addition, perioperative outcomes and complications, including the preservation of antegrade ejaculation, are significantly worse due to the need for a bilateral template and the treatment effect of chemotherapy on the retroperitoneal tissue [3, 4]. Based on the favorable outcomes of L-RPLND in the postchemotherapy setting , the natural evolution of the R-RPLND has included attempts by experienced robotic surgeons to perform postchemotherapy R-RPLND (PC-RPLND) in selected patients. To date, only two smaller series have demonstrated early feasibility [12, 32]. The Mayo Clinic R-RPLND experience included nine patients who were postchemotherapy. Notably, their median LNY (18 nodes), blood loss (313 mL), and LOS (2.2 days) were not significantly different from their primary R-RPLND patients; however, their PC-RPLND patients experienced significantly greater operative time (369 mins versus 311 mins, p=0.03). Notably, two patients required open conversion in the postchemotherapy group, which represents a conversion rate of 22.3%. At a median follow-up of 22 months, there were no retroperitoneal recurrences. Kamel et al., in a series of 12 patients, experienced a 91.7% completion rate with only a single open conversion due to what the author considered poor patient selection . It is also worth mentioning that Stepanian et al. included four robotic PC-RPLNDs with no conversions . At a median follow-up of 31 months, there were no recurrences. Currently, the literature on robotic PC-RPLND outcomes is immature and requires larger series before conclusions regarding oncologic and safety performance can be made. From these smaller series, we can conclude that R-RPLND in the postchemotherapy setting is feasible with an understandably higher rate of open conversion. Postchemotherapy RPLND has inherent objectives that are different from the primary RPLND setting, and incomplete control of the retroperitoneum or an incomplete resection during RPLND is a predictor of worse survival in the postchemotherapy setting . Therefore, it is our position that oncologic outcomes remain the priority in the postchemotherapy setting, and oncologic outcomes should not be leveraged against perioperative outcomes. As larger, multi-institutional cohorts are published, we can hopefully better evaluate the merits and technique of a robotic PC-RPLND.
The first L-RPLND performed in 1992 and the first R-RPLND performed in 2006 marked the beginnings of a minimally invasive era to reduce the treatment morbidity for testicular cancer survivors. Early results from expert robotic surgeons at high-volume academic institutions have demonstrated both feasibility as well as favorable early oncologic outcomes and complication rates in the primary RPLND setting compared to O-RPLND and L-RPLND. Larger, prospective studies are required to better evaluate long-term oncologic outcomes and complication rates in both the primary and postchemotherapy settings.