{"paper_id":"4365fa36-900c-4655-af22-9b44bbbb21da","body_text":"Comparison of perioperative outcomes between\nconventional laparoscopy and robotic-assisted\nsurgery in the surgical treatment of endometriosis:\na retrospective study\nMarina Quaglio Oinegue Fulfaro \nEinstein Hospital Israelita\nTatiani Araujo Pandim \nEinstein Hospital Israelita\nGustavo Anderman Silva Barison \nEinstein Hospital Israelita\nPriscilla Duarte Pessoa \nEinstein Hospital Israelita\nGuilherme Albuquerque Sampaio \nEinstein Hospital Israelita\nJúlia Pereira Junho e Silva \nEinstein Hospital Israelita\nAntonio Phelipe Junior \nEinstein Hospital Israelita\nMariano Tamura Vieira Gomes \nEinstein Hospital Israelita\nResearch Article\nKeywords: Endometriosis, Minimally Invasive Surgery, Laparoscopy, Robotic Surgery, Perioperative\nOutcomes\nPosted Date: September 1st, 2026\nDOI: https://doi.org/10.21203/rs.3.rs-10729934/v1\nLicense:   This work is licensed under a Creative Commons Attribution 4.0 International License.  \nRead Full License\nPage 1/11\n\nAdditional Declarations: No competing interests reported.\nVersion of Record: A version of this preprint was published at Journal of Robotic Surgery on September\n28th, 2026. See the published version at https://doi.org/10.1007/s11701-026-03973-7.\nPage 2/11\n\nAbstract\nObjective\nTo compare perioperative outcomes between laparoscopy and robotic-assisted surgery in the surgical\ntreatment of endometriosis in a high-volume tertiary center.\nMethods\nRetrospective, observational, and analytical study, including patients who underwent minimally invasive\nsurgery for the treatment of endometriosis at Einstein Hospital Israelita between 2018 and 2022. A total\nof 520 patients were included, with 260 patients in each surgical group. Outcomes evaluated included\nsurgical time, anesthetic time, length of hospital stay, estimated blood loss, intraoperative complications,\nneed for intensive care, conversion to laparotomy, and early readmission.\nResults\nDemographic characteristics were similar between the groups. Robotic-assisted surgery was associated\nwith significantly shorter operative and anesthetic times, in addition to shorter hospital stays, when\ncompared to laparoscopic surgery. There was no statistically significant difference between the\napproaches in terms of complication rates, surgical conversion, need for intensive care, blood\ntransfusion, or early readmission.\nConclusion\nBoth approaches demonstrated a similar safety profile in the surgical treatment of endometriosis.\nRobotic-assisted surgery showed greater perioperative efficiency in a center with a mature learning\ncurve, suggesting a potential advantage in highly complex scenarios.\nIntroduction\nEndometriosis is a chronic and benign gynecological disease that affects approximately 10% of women\nin reproductive age and is associated with chronic pelvic pain, dysmenorrhea, dyspareunia, and infertility,\nwith possible significant impact on quality of life [1–4]. Surgical treatment is indicated in cases who are\nrefractory to clinical management or in the presence of specific complications, and minimally invasive\nsurgery occupies a space as the gold standard treatment, especially in the more advanced stages of the\ndisease [5–8].\nLaparoscopic Surgery (LS) has established itself as a consolidated approach in the surgical treatment of\nendometriosis because it has proved, along the years, visualization enhancement, lower morbidity, and\nPage 3/11\n\nfaster recovery when compared to laparotomy. More recently, robotic-assisted laparoscopic surgery\n(RALS) has been incorporated as an alternative tool for complex gynecological procedures, offering\ntechnical advantages such as three-dimensional vision, greater instrumental dexterity, and improved\nergonomics [9–11].\nHowever, the literature still presents conflicting results regarding the perioperative benefits of robotic-\nassisted surgery in the treatment of endometriosis, particularly in relation to surgical time, anesthetic\ntime, and hospital stay. Initial studies often associated RALS with longer operative duration, mainly\nattributed to docking time and logistical limitations of the platform [10–12]. On the other hand, data from\ncenters with high surgical volume and a mature learning curve suggest that these differences can be\nminimized or even reversed with the maturity of the robotic program.\nConsidering the importance of this pathology and the impact on the quality of life of patients, the\nobjective of this study was to compare the perioperative outcomes of surgeries performed for the\ntreatment of endometriosis via laparoscopy versus robot-assisted laparoscopic surgery in a solid and\nmature robotic center, in order to improve the care provided to patients at the institution.\nMethods\nThis retrospective observational study was based on the review of electronic medical records of patients\nwho underwent minimally invasive surgery for the treatment of endometriosis at Einstein Hospital\nIsraelita (EHI), from 2018 to 2022.\nPatients who underwent surgical procedures by laparoscopic surgery or by robot-assisted surgery with\nindication for endometriosis treatment were included. After approval by the Research Ethics Committee\nof the institution, the eligible medical records were identified by the surgery department and the data\nwere collected in an anonymized manner through the REDCap platform.\nThe sample selection was carried out in a balanced manner, with 260 patients in each surgical group,\nusing a random selection process to avoid selection bias. The medical records were reviewed for\ncompliance with the inclusion criteria before the final analysis.\nThe variables analyzed included demographic and clinical characteristics, surgical time, anesthetic time,\nlength of hospital stay, estimated blood loss, need for transfusion, use of intensive or semi-intensive\ncare unit, intraoperative complications, conversion to laparotomy, surgical reapproach, and early\nreadmission.\nFor the calculation of the sample size expected for statistical significance, a p < 0.05, a mean standard\ndeviation of 58 populations, and an error of 5% were considered, as based on the article from Ádám\nCsirzó et al. (2023). Thus, we analyzed 520 medical records, equally distributed between the two surgical\napproaches.\nPage 4/11\n\nStatistical Analysis\nThe data were described for the general sample and by two groups, which were formed by type of\nsurgical technique for endometriosis treatment (laparoscopy and robot-assisted laparoscopy), using\nabsolute and relative frequencies for qualitative variables and measures such as median, mean,\nstandard deviation, quartiles, minimum and maximum for quantitative variables. To compare the\noutcomes between the groups, association analyses were performed between qualitative variables,\nwhere chi-square tests were performed (Agresti, 2007), Fisher's exact tests (Agresti, 2007) or likelihood\nratio tests (Agresti, 2007) depending on the variables that were compared. Also, to compare quantitative\nvariables, their distributions were tested with Shapiro-Wilk normality tests (Altman & Matthews, 1996),\nfor which all the quantitative variables tested rejected normality and, subsequently, Mann-Whitney tests\nwere performed (Altman & Matthews, 1996) to compare the distribution between the groups. For the\nconstruction of boxplots in the visualization of quantitative variables to verify the differences between\nthe groups, the variables were transformed with logarithm due to the large number of discrepant points.\nThe analyses were carried out with the aid of the R program (R Core Team, 2021) and considering a\nsignificance level of 5%.\nResults\nWe retrospectively analyzed 520 medical records of patients who underwent surgical treatment for\nendometriosis at the EHI between 2018 and 2022, 260 of whom underwent conventional laparoscopy\n(LS) and 260 underwent robotic-assisted surgery (RALS). The sample was balanced, with 260 patients in\neach group.  \nSociodemographic characteristics were similar between the LS and RALS groups. The mean age was\n36.7 ± 7.1 years in the LS group and 36.5 ± 7.9 years in the RALS group (p = 0.538). The mean body mass\nindex was also similar between the groups (24.5 ± 4.3 kg/m² in LS versus 24.4 ± 4.3 kg/m² in RALS; p =\n0.801). Regarding marital status, most patients in both groups were married (63.5% in the LS group and\n61.0% in the RALS group), followed by single patients (24.2% and 26.6%, respectively), with no\nstatistically significant difference between the distributions (p = 0.801). Likewise, no significant\ndifferences were observed in terms of ethnicity, although a high proportion of unreported data in both\ngroups stands out. \nSignificant differences were observed in the surgical history and habits of the patients (Tables 1 and 2).\nPatients undergoing RALS reported a higher proportion of previous laparotomic surgeries (29.5%)\ncompared to the LS group (18.3%). On the other hand, the LS group reported a higher incidence of\nprevious laparoscopic surgeries (20.8%) compared to the RALS group (12.7%). Patients in the LS group\nhad a significantly higher rate of prior surgery for endometriosis (18.1%) compared to the RALS group\n(5.8%). Regarding the clinical comorbidities evaluated, no statistically significant differences were\nobserved between the groups submitted to laparoscopic and robotic surgery.\nPage 5/11\n\nThere was a significant difference in the nature of the procedures performed between the groups.\nResection of endometriosis foci combined with other procedures was more prevalent in LS (50.4%),\nwhereas the RALS group had a higher proportion of procedures involving resection of endometriosis foci\n(71.2%). This association is detailed in Table 3.\nRegarding main perioperative outcomes, including operative time, anesthetic time, and length of hospital\nstay, there were statistically significant differences between the approaches (Table 3). Mean surgical\ntime (ST) (in minutes) was significantly shorter in the RALS group (137.2 ± 131.9 min) compared to the\nLS group (152.7 ± 96.2 min). Similarly, Mean anesthetic time (AT) (in minutes) was significantly shorter\nin the RALS (177.7 ± 106.4 min) compared to the LS (201.0 ± 104.9 min). Postoperative length of stay\n(LOH) (in hours) was also significantly shorter for the RALS group (mean of 38.7 hours) compared to the\nLS group (mean of 50.2 hours). By isolating only patients whose main diagnosis in the\nanatomopathological examination was endometriosis, these trends were maintained: all surgical times,\nanesthetic, and hospital stay were significantly lower in the RALS (Table 4).\nIn order to analyze more specifically the outcomes of the two approaches and to reduce confounding\nbias, a comparison was made considering only surgeries for resection of endometriosis foci without\nassociation with other procedures, whether gynecological or non-gynecological.\nAn association was found between the technique used and the new procedure classification: 51.9%\n(135) of the patients with endometriosis who underwent robot-assisted surgery and 35% (91) of those\noperated by laparoscopic did not undergo any other procedure in the same surgical procedure. The p-\nvalue observed was < 0.001, highlighting a significant association between the variables.\nWith significant p-values, surgery (in minutes) and anesthesia (in minutes) length were statistically\ndifferent according to the technique performed, all shorter in the robot-assisted pathway. As for the\npostoperative length of stay and the amount of blood loss, there is no evidence of an association\nbetween the variables and the technique (Table 5).\nAn additional analysis was also conducted with the aim of reducing bias introduced by the performance\nof non-gynecological procedures during the same surgical time. Only the 487 patients who underwent\ngynecological procedures were evaluated (242 in the LS group and 245 in the RALS group), excluding\nthose who underwent other non-gynecological procedures at the same time. The results of this analysis\ncorroborate the previous findings: mean surgical time was significantly shorter in the RALS group (131.2\nmin) compared to the LS group (150.9 min; p < 0.001), as was mean anesthetic time (171.4 min vs.\n200.0 min; p < 0.001). Postoperative length of stay was also significantly shorter in the RALS group\n(mean of 40.0 hours vs. 53.6 hours in the LS group; p = 0.011). No statistically significant differences\nwere observed between the groups regarding estimated blood loss, need for intensive care unit\nadmission, early readmission, or intraoperative complications, reinforcing the equivalent safety profile\nbetween the approaches in this more homogeneous population.\nPage 6/11\n\nRegarding safety outcomes, the analysis of the aggregate variable of \"some intraoperative complication\"\n(bladder injury, ureteral injury, intestinal injury, vascular trauma, postoperative bleeding, infection, vaginal\ndome dehiscence, sepsis, and conversion to laparotomy) did not show a significant association with the\nsurgical technique (Table 6). The use of Intensive Care Unit (ICU) or Semi-Intensive Care Unit was rare in\nboth groups (LS: 1.9%; RALS: 0.4%), with no statistical significance. As well as conversion to laparotomy,\nwhich occurred in 1 case (0.4%) in LS and in 0 cases (0.0%) in RALS (Table 5). There was no statistically\nsignificant difference in estimated blood loss (RPE) between the groups (LS: 82.2 mL; RALS: 55.6 mL). In\nthe subgroup of patients with endometriosis, the result was also not significant. Regarding readmission\nrate, it occurred in 5.0% in the LS and 3.1% in the RALS, also with no statistical difference.\nDiscussion\nThe main objective of this study was to compare the perioperative outcomes between laparoscopic\nsurgery (LS) and robotic-assisted surgery (RALS) in the treatment of endometriosis at a referral center,\nEinstein Hospital Israelita over five years. The main findings demonstrate that both approaches had a\nsimilar safety profile, with low complication rates, surgical conversion, and early readmission. However,\nthe RALS was associated with greater perioperative efficiency, as evidenced by significantly shorter\nsurgical, anesthetic, and hospital length of stay.\nMinimally invasive surgery is widely recognized as the gold standard for the surgical treatment of\nendometriosis, especially in more complex cases, in which complete resection of the lesions requires\nhigh technical precision and anatomical preservation [10]. Although the robotic platform was, in its early\nyears, used to be associated with longer operative time, especially during its implementation phase,\nmore recent evidence suggests that this alleged disadvantage can be overcome by consolidating the\nlearning curve and standardizing intraoperative flows.\nThe results of this study contrast with much of the previus literature, which describes longer surgical\nduration associated with RALS compared to LS [10–12]. Traditionally, the increase in operative time in\nrobotic surgery has been attributed to docking time, the need for specific instrumentation, and logistical\nlimitations in extensive or extrapelvic procedures. In some studies, docking time alone exceeded 10 to\n15 minutes [11]. In the present study, however, RALS demonstrated superior temporal performance,\nsuggesting that, in a mature and solid robotic program and institution, these logistical factors become\nless relevant in the face of the technical advantages of the platform.\nThe shorter operative time observed may be related to multiple institutional factors, including high\nsurgical volume, consolidated experience of the surgical, anesthetic and multidisciplinary teams,\nstandardized surgical protocols, and efficient integration between team and technology. The three-\ndimensional vision, tremor filtration, and greater freedom of movement provided by the robotic platform\ncan favor more precise and faster dissections, particularly in scenarios of deep endometriosis or\nanatomy distorted by adhesions [11]. Another relevant finding was the significant reduction in the length\nof hospital stay in the group undergoing RALS. This result differs from some previous reports, in which\nPage 7/11\n\nrobotic-assisted surgery was associated with longer hospital stay [12]. In the context evaluated, this\ndifference may reflect the adoption of accelerated recovery protocols, the shorter duration of the\nprocedure, and the early clinical stability of patients undergoing RALS, favoring early hospital discharge\nwith no negative impact on safety outcomes. Although these results point to a clear advantage of the\nRALS in the institutional context evaluated, their interpretation requires careful consideration of the\nmethodological barriers of the present study.\nRegarding safety, no statistically significant differences were observed between the approaches in terms\nof the rate of intraoperative complications, need for transfusion, use of intensive care unit, or conversion\nto laparotomy. These findings reinforce that both LS and RALS are safe approaches for the surgical\ntreatment of endometriosis when performed in specialized centers, corroborating previously published\ndata and reinforcing the space of laparoscopy, which is still an important tool in the treatment of\nendometriosis. [10–12].\nThis study has limitations inherent to its retrospective and observational design, which prevents\ncomplete control of potential selection biases and confounding factors. Although the sample was\nbalanced between the groups, the absence of detailed information on the severity of endometriosis,\nclassification of lesions, and long-term clinical follow-up limits the evaluation of outcomes such as\ndisease recurrence, pain control, fertility, and quality of life. In addition, the institution's open clinical staff\nmodel makes it difficult to access outpatient and follow-up data recorded outside the institutional\nmedical record. Despite these limitations, the results related to immediate perioperative outcomes were\nrobust and allowed safe comparisons between the two surgical approaches.\nRobotic-assisted surgery for the treatment of endometriosis demonstrated safety comparable to\nlaparoscopic surgery, but with remarkable superiority in efficiency, evidenced by shorter surgical and\nanesthetic times, and shorter hospital stay. These findings suggest that, after the learning curve has\nbeen overcome by the surgical and room team, RALS may offer a real advantage in optimizing\nperioperative outcomes compared to LS in endometriosis procedures.\nThe robotic platform, with its improved ergonomics and capabilities (3D vision and increased dexterity),\n(11) has the potential to not only enable more surgeons to perform complex minimally invasive surgeries,\nbut also to increase temporal efficacy in centers with high experience by challenging the assumption\nthat RALS is inherently associated with longer operative times between RALS and longer operative time.\nProspective randomized studies focusing on cost-effectiveness and long-term outcomes are needed to\nconsolidate the optimal indication of RALS versus LS in the setting of endometriosis.\nConclusion\nIn conclusion, RALS provides similar perioperative outcomes in safety to LS, but was associated with\nsignificant superior efficiency metrics in the experience of a mature high-complexity center, in addition to\nproviding greater ergonomic advantages and technical precision. Although cost and long-term outcomes\nPage 8/11\n\n(such as recurrence or fertility preservation) were not evaluated in this retrospective study, the use of\nRALS should be considered a highly competitive option for the treatment of endometriosis, especially in\npotentially more complex cases, and should be optimized and matured in tertiary centers to maximize its\nefficiency. Additional prospective studies are needed to assess cost-effectiveness and confirm these\nfindings in different settings.\nDeclarations\nFunding\nThe authors declare that there was no receipt of funding, scholarships, grants or any other type of\nfinancial support for the conduct of this study.\nConflicts of Interest\nThe authors declare that they have no financial or non-financial conflicts of interest related to the content\nof this manuscript.\nEthical Approval\nThis retrospective study was conducted in accordance with the principles of the Declaration of Helsinki.\nThe project was approved by the Research Ethics Committee of the Einstein Hospital Israelita.\nConsent to Participation\nDue to the retrospective nature of the study and the use of anonymized data, individual informed consent\nwas waived by the Research Ethics Committee of the institution.\nConsent to Publication\nNot applicable. This study contains no identifiable patient data.\nData Availability\nThe data supporting the findings of this study are not publicly available due to institutional constraints\nrelated to the confidentiality of medical records but may be made available upon reasonable request to\nthe corresponding authors and after institutional approval.\nAuthors' Contributions\nAll authors contributed to the conception and design of the study. Data collection and analysis were\ncarried out by the authors. The writing of the manuscript was carried out by the authors, who critically\nreviewed the intellectual content and approved the final version submitted.\nPage 9/11\n\nReferences\n1. Eskenazi B, Warner ML (1997) EPIDEMIOLOGY OF ENDOMETRIOSIS. Obstetrics and Gynecology\nClinics of North America, 24(2), 235–258. 10.1016/s0889-8545(05)70302-8\n2. Silva JC, Valerio F, Herren H, Troncon J, Garcia R, Nogueira Neto O (2021) Endometriose: aspectos\nclínicos do diagnóstico ao tratamento. Femina 49(3):134–141 Acesso em: 20 set 2023.\nhttps://www.febrasgo.org.br/media/k2/attachments/FeminaZ2021Z49Z-Z3.pdf\n3. Sampson JA (1927) Metastatic or embolic endometriosis, due to the menstrual dissemination of\nendometrial tissue into the venous circulation. Am J Pathol 3(2):93–110\n4. Porpora MG, Koninckx PR, Piazze J, Natili M, Colagrande S, Cosmi EV (1999) Correlation between\nendometriosis and pelvic pain. The Journal of the American Association of Gynecologic\nLaparoscopists, 6(4), 429–434. 10.1016/s1074-3804(99)80006-1\n5. Agarwal SK, Chapron C, Giudice LC, Laufer MR, Leyland N, Missmer SA et al (2019) Clinical\ndiagnosis of endometriosis: a call for action. Am J Obstet Gynecol 220(4):354e1–354e12.\n10.1016/j.ajog.2018.12.039\n6. Nogueira Neto J, Abrão MS, Schor E, Rosa-e-Silva JC (2022) Classificação cirúrgica da\nendometriose. Femina 50(8):455–460 Acesso em: 20 set 2023.\nhttps://docs.bvsalud.org/biblioref/2022/10/1397882/femina-2022-508-545-460.pdf\n7. Vercellini P, Trespidi L, De Giorgi O, Cortesi I, Parazzini F, Crosignani PG (1996) Endometriosis and\npelvic pain: relation to disease stage and localization. Fertil Steril 65(2):299–304. 10.1016/S0015-\n0282(16)58089-3\n8. Podgaec S (2014) Endometriose. São Paulo: Federação Brasileira das Associações de Ginecologia e\nObstetrícia. FEBRASGO)\n9. Horne AW (2022) Pathophysiology, diagnosis and management of endometriosis. BMJ\n379:e070750. 10.1136/bmj-2022-070750\n10. Nezhat CR, Stevens A, Balassiano E, Soliemannjad R (2015) Robotic-assisted laparoscopy vs\nconventional laparoscopy for the treatment of advanced stage endometriosis. J Minim Invasive\nGynecol 22(1):40–44. 10.1016/j.jmig.2014.06.002\n11. Nezhat C, Lewis M, Kotikela S, Veeraswamy A, Saadat L, Hajhosseini B, Nezhat C (2010) Robotic\nversus standard laparoscopy for the treatment of endometriosis. Fertil Steril 94(7):2758–2760.\n10.1016/j.fertnstert.2010.04.031\n12. Raimondo D, Alboni C, Orsini B, Aru AC, Farulla A, Maletta M et al (2021) Comparison of\nperioperative outcomes between standard laparoscopic and robotic-assisted approach in patients\nwith rectosigmoid endometriosis. Acta Obstet Gynecol Scand 100(7):1306–1315.\n10.1111/aogs.14170\nTables\nTables 1 to 6 are available in the Supplementary Files section.\nPage 10/11\n\nSupplementary Files\nThis is a list of supplementary files associated with this preprint. Click to download.\nTable1to6.docx\nPage 11/11","source_license":"CC0","license_restricted":false}