Given the limited overall survival benefits and considerable adverse events after RP for D'Amico low-risk PCa, the role of RP in managing D'Amico low-risk PCa remains highly contentious (3, 4). While RP for D'Amico immediate- and high-risk PCa could achieve favorable survival benefits from preventing further metastatic seeding of potentially lethal clones of PCa cells (9). In 2020, RP is widely perceived as appropriate for men with intermediate-risk and high-risk PCa rather than those bearing D'Amico low-risk PCa (9). Although RARP has been widely diffused for surgically handling localized PCa, the paucity of high-level evidence still triggers the controversy on the impacts of RARP and LRP on oncological and functional outcomes obtained after surgery. What’s worse, there has been no study which was immersed in comparing RARP and LRP for intermediate-risk and high-risk PCa up to now, while the cogent evidence concerning the functional and oncological efficacy of RARP and LRP for immediate- and high-risk localized PCa is of great clinical importance.
In this content, we designed this retrospective study which is the first one comparing RARP and LRP for immediate- and high-risk PCa. To eliminate the influences of any significant differences in any preoperative factors and selection bias, we rigorously utilized the PM method to guarantee the similarity in all preoperative parameters between the two groups. Within the well-balanced matched cohort, our results revealed the superiority of RARP in functional preservation coupled with fewer postoperative ≤ Grade II complications than LRP without cancer control being compromised for managing immediate- and high-risk PCa.
As regards the extended mean OT in the LRP group, this significant difference may be attributable to the fact that the robotic platform facilitates suturing, one of the most challenging procedures during the standard laparoscopic approach (20), and this advantage is even more obvious when comparing RARP and LRP for the immediate- and high-risk patients enrolled in our analysis. As to the similar mean EBL and transfusion rates following RARP and LRP, the similarity can be explained by the counterbalance between the contributing factors including the better visualization, improved dexterity, and higher precision to minimize bleeding during RARP and unfavorable factors leading to EBL including more ePLNDs and nerve sparing procedures done in the RARP group. Both Johnson et al. (21) and Papachristos et al. (22) also achieved similar outcomes regarding EBL and OT after RARP and LRP to ours, in spite of the drastic variation of mean EBL and OT offered from different medical centers. The variation could be easily interpreted when taking the surgeons’ experience and patients’ and tumors’ characteristics into account.
Although both LRP and RARP are minimally invasive, the better visualization and higher precision offered by the robotic platform could help in further reducing the operative invasiveness and the hazard of organ injures (20, 21), which may translate into the significantly lower proportion of overall and ≤ Grade II postoperative complications after RARP in our analysis. However, these advantages mentioned above may be restricted by the higher rate of ePLNDs underwent in the RARP group which was associated with the occurrences of symptomatic lymphocele, the most frequent > Grade II complication in our study, thus resulting in similar rates of > Grade II postoperative complications. The comparability of the incidence rates of postoperative > Grade II complications between the two groups in our analysis was consistent with those reported in the contemporary series (14, 20–24) comparing RARP and LRP, demonstrating the similar operative safety of RARP and LRP for immediate- and high-risk PCa in experienced hands.
Surgical approach to RP should be tempered with critical significance of cancer control, especially when managing immediate- and high-risk PCa. Consistent with the results reported in published analyses (13, 14, 25), no significant difference in PSM rate was discovered in our study comparing RARP (17.6%) and LRP (24.7%) for immediate- and high-risk PCa. Evaluated BMI and large prostate volume were considered as the independent predictors of PSMs in men with organ-confined PCa (26), and cumulative evidences revealed that margin status following RP was related to surgical experience (26, 27). Fortunately, all these influencing elements were under stringent control with PM method being employed in this single-center analysis, thus greatly contributing to the similarity in PSM rates after RARP and LRP. Of note, compared with the 15% mean rate of PSMs in RARP series including more than 100 cases (26), 17.6% rate of PSMs acquired after RARP in our analysis was relatively high even in highly experienced hands when removing immediate- and high-risk PCa, coordinating the caution that the more extensive the cancer, the higher the possibility of positive margins (26). Although PSMs in RP specimens were in consistent correction with an enhanced risk of PSA relapse (28, 29), the long-term impacts of PSMs on more robust clinical endpoints of the disease is variable and mostly depends on other variables, such as Gleason score, pathologic stage, and preoperative PSA (16, 30). Intriguingly, most of these decisive factors including Gleason score and preoperative PSA were the basis of D'Amico risk classifications, namely, the clinical endpoints, such as clinical recurrence rates, largely relied on preoperative baseline characteristics rather than PSMs after RP. In alignment with other series (14, 25) comparing RARP and LRP, the similarity in the BCR-free survivals obtained after RARP and LRP was still existing, corroborating the equivalent potency of the two procedures in cancer control even when managing immediate- and high-risk PCa.
The aims of RP are to completely eradicate localized PCa whilst, whenever possible, preserves UC and erectile function, namely, a trifecta outcome (4). Urinary incontinence after RP is one of the most adverse events that negatively impact patients’ quality of life (20, 31). Multiple pathophysiologic mechanisms contribute to the emergence of post-prostatectomy incontinence (PPI). In addition to the biological/preoperative parameters encompassing the patient age at time of surgery, pre-existing lower urinary tract symptoms, high BMI, and abnormal bladder function, the impairments of the integrity of anatomic supporting structures and neural components during the RP procedure appear to be crucial contributing factors to the development of PPI (31, 32). In our analysis, preoperative/biological parameters are comparable between the RARP and LRP groups with PM method being applied, but the robotic platforms allowed better preservation of membranous urethra and nerve branches and reconstruction of bladder neck, thus supporting the higher UC probability after RARP over the whole follow-up period. In the prospective randomized controlled study reported by Porpiglia et al. (25), UC rate after RARP was also significantly higher than that after LRP for localized PCa over the 5-year follow-up period. Our results also corroborated the outcomes obtained in the first multicenter, randomized, patient-blinded controlled trial (LAP-01) (14) which demonstrated the improved postoperative return to UC of RARP over LRP. The advantage of robotic platforms in better surgical vision and higher precision for preserving the neurovascular structures could be greatly responsible for the superior erectile function recovery after RARP than that obtained after LRP.
Notably, several limitations should be taken into consideration when interpreting our conclusions. Structural shortages in data collection were inevitable in a retrospective setting of our analysis. The study population, although well-balanced between the two groups, is relatively small. The long-term oncological survivals and functional recoveries could not be further evaluated over the relatively limited follow-up lengths. Certain complications may be undervalued, especially ≤ Grade II complications, in spite of the elaborative investigation of medical records and telephone interview.
Despite these limitations, our study is the first one designed to assess the perioperative, functional, and oncological outcomes acquired after RARP and LRP for localized immediate- and high-risk PCa up to now, and our conclusions are drew and strengthened on the basis of the comparability of all perioperative elements between the two arms and rigorous methodology.