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ORIGINAL ARTICLE
Year : 2015  |  Volume : 11  |  Issue : 8  |  Page : 258-264

Comparison of conventional laparoscopy and robotic radical hysterectomy for early-stage cervical cancer: A meta-analysis


Department of Gynaecology, Jining Medical College Affiliated Hospital, Jining Medical University, Jining, Shandong 272029, PR, China

Date of Web Publication26-Nov-2015

Correspondence Address:
Wang Yunfei
Jining Medical College Affiliated Hospital, 79, Guhuai Road, Jining, Shandong 272029
China
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-1482.170533

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 > Abstract 

Background: Cervical cancer continues to be a global burden for women, with >500,000 cases and 275,000 deaths reported annually. Resources-rich countries have seen a dramatic reduction in the prevalence of invasive cervical cancer due to widely accessed radical hysterectomy (RH). We aimed to compare initial surgical outcomes and complication rates of conventional laparoscopic RH (LRH) and robotic RH (RRH) for treating cervical cancer through a systematic meta-analysis.
Methods: PubMed, EMBASE, and the Cochrane Library databases were systematically searched for all relevant studies. Data were abstracted independently. A meta-analysis was performed to compare intra- and post-operative outcomes for the two techniques.
Results: A total of 12 clinical trials were identified. Meta-analysis showed that although LRH and RRH were similar in terms of operating time, the length of hospital stay, and a number of pelvic lymph nodes resected, RRH presented less blood loss and overwhelming advantage against LRH with the respect of complications.
Conclusion: RRH may be a reliable technique for treating early cervical cancer. Available evidence suggests that it is better than LRH for postoperative recovery, while the two techniques involve similar surgical outcomes and share the same limits in clinical practice.

Keywords: Cervical cancer, laparoscopy, meta-analysis, robotic radical hysterectomy, surgical outcomes


How to cite this article:
Xianhua H, Shuzhai H, Yunfei W. Comparison of conventional laparoscopy and robotic radical hysterectomy for early-stage cervical cancer: A meta-analysis. J Can Res Ther 2015;11, Suppl S4:258-64

How to cite this URL:
Xianhua H, Shuzhai H, Yunfei W. Comparison of conventional laparoscopy and robotic radical hysterectomy for early-stage cervical cancer: A meta-analysis. J Can Res Ther [serial online] 2015 [cited 2020 Sep 18];11:258-64. Available from: http://www.cancerjournal.net/text.asp?2015/11/8/258/170533


 > Introduction Top


Cervical cancer continues to be a global burden for women, with >500,000 cases and 275,000 deaths reported annually.[1] Resource-rich countries have seen a dramatic reduction in the prevalence of invasive cervical cancer due to widely accessed screening program and mature application of radical hysterectomy (RH) in early-stage cervical cancer patients.[2],[3],[4],[5]

As we all know that conventional surgical management of early-stage cervical carcinoma is RH,[2],[6] which is associated with postoperative morbidities such as bladder dysfunction, sexual dysfunction, and colorectal motility disorders. Accidental damage to the pelvic autonomic nerves during surgery is thought to be a major cause of these morbidities. Improving surgical treatment as well as the postoperative quality of life is increasingly important challenges given that more than 54% of women diagnosed with cervical cancer are younger than 50 years. As a result of advances in minimally invasive surgery, laparoscopic RH (LRH)[6],[7],[8] is now performed routinely around the world. While this technique is less invasive than RH, it can still lead to substantial rates of postoperative morbidity. In an effort to reduce postoperative morbidity, many gynecologists have focused on such surgical approach that is known as robotic RH (RRH),[9],[10],[11] was invented by Japanese gynecologists. RRH has been adopted and developed over the last 20 years by surgical schools around the world. Many clinicians believe that the robotic approach is associated with lower postoperative morbidity than conventional RH, with similar clinical efficacy and safety. We decided to test this belief rigorously by conducting a meta-analysis of pooled studies.[12],[13]


 > Methods Top


Search strategy

All relevant studies published in English and Chinese ranged from 2007 to 2015 were identified through systematic searches in PubMed, EMBASE, and the Cochrane Library database. The search terms used were RRH, RH, conventional laparoscopy, LRH, and all these terms in combination with cervix carcinoma or cervical cancer. Reference lists in all relevant articles were also manually searched.[10]

Study eligibility

A study was included in the meta-analysis if it involved patients with proven cervical cancer, regardless of age, ethnicity or location, a pair-matched or non-pair-matched controlled design, or a case–control design; laparotomy or laparoscopy; comparison of surgical outcomes of LRH with RRH; and evaluation of at least one outcome from among following: Operating time, intraoperative blood loss, hospital stay, pelvic lymph nodes, complications, and recovery time.[14]

A study was excluded from the study if it failed to report the principal demographic and clinicopathological findings of patients, including age, body mass index, International Federation of Gynecology and Obstetrics stage, histological findings, and tumor size.[15],[16]

Data extraction

We carried out literature searches and identified eligible articles based on the inclusion and exclusion criteria. Then we extracted data from each study independently, including the first author, publication year, country, study design, patient characteristics, and data on the outcomes in the inclusion criteria. Discrepancies in extracted data were resolved by consensus.

Assessment of study quality

We assessed the quality of included studies using the guidelines in the Cochrane Handbook for Systematic Reviews of Interventions. The assessment tool contained six core items: Sequence generation, allocation concealment, blinding, incomplete outcome data (e.g. about follow-up/withdrawals), selective outcome reporting, and other potential sources of bias (e.g., comparability of groups). Each study was classified as having a low, moderate, or high risk of bias.

Data management and statistical analysis

Data for dichotomous variables were analyzed using relative risk while data for continuous variables with the same measurement unit were analyzed using the weighted mean difference; in all cases, the binomial 95% confidence interval (95% CI) was also calculated. All statistical tests were performed using RevMan 5.2 software (Cochrane Collaboration). Possible heterogeneity among studies was evaluated using Chi-squared-based Q-test or Chi-square test. Heterogeneity was also estimated using the I2 index, which describes the percentage of total variation across studies that is due to heterogeneity rather than chance. A fixed-effects model was used if no statistical heterogeneity existed (P > 0.1, I2 ≤ 50%); otherwise, a random-effects model was used, and sensitivity analysis was performed.

We planned to perform subgroup analysis in the event that we were able to identify the source of clinical heterogeneity or in the event that the included studies encompassed a range of study designs. We also planned to provide a descriptive analysis of data from different studies if they could not be combined into a meta-analysis. We planned to assess publication bias by visual inspection of Begg's funnel plots if we could include a sufficient number of studies in the analysis.


 > Results Top


Search results

We identified a total of 28 relevant studies in our database searches. After eliminated the reviews and those concerning patients transferred to receive laparotomy or robot-assisted operation, 19 were remained to read in detail. Since three of them lack extractable data or focus only on one of the two techniques, 12 were remained as final references [Figure 1]. Of these, one published in 2011, which was conducted by Sert et al. to compare surgical outcomes and postoperative complications of conventional laparoscopic hysterectomy with that of robot-assisted LRH, was also included in this meta-analysis. We limited all the whole literature mining within early-stage cervical cancer so that we could ensure the similar health issues in patients involved in this study. The scientific objectivity of conclusions drawn from this meta-analysis was based on some main characteristics of all these included studies [Table 1]. Since patients' physical conditions influence the outcome of treatment, patients' ages and BMIs potentially accounted for our inclusive criteria as samples in these 12 studies framed in the same scale. Besides, we also noticed that different terms were used to refer laparoscopic radical hysterectomy among these studies, for example, laparoscopic radical hysterectomy in the study of Chong et al. was referred to as TLRH (total laparoscopic radical hysterectomy) while the counterpart in that of Estape et al. simply was LRT. The expressional differences were not taken into account in our study.
Figure 1: Flowchart of study selection

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Table 1: Main characteristics of all the included studies

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Operating time

While 7 of 12 studies reported operating time,[12],[17],[18],[19],[20],[21],[22],[23],[24],[25] presenting as means ± standard deviations, we took them into account. Operating time did not differ significantly between the RRH (n = 304) and LRH (n = 322) groups (95% CI [− 19.46, 1.88], P = − 8.79), since slight heterogeneity existed (heterogeneity: χ2 = 10.10, df = 6 [P = 0.12]; I2 = 41%, [Figure 2]).
Figure 2: Forest plot of operating-room time

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Estimated blood loss

Six RH studies reported data on intraoperative blood loss. Heterogeneity (heterogeneity: χ2 = 22.95, df = 5 [P = 0.0003]; I2 = 78%) was calculated, as we know that I2 = 78%, much greater than the standard level 50%, so a random-effects model was applied. However, it had little effect on heterogeneity, for which the source of heterogeneity was attributed to other reasons. The RRH group (n = 270, mean value = 112.87 ml) showed much less blood loss when comparing with LRH group (n = 291, mean value = 188.32 ml, [Figure 3]).
Figure 3: Forest plot of estimated blood loss

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Length of hospital stay

Seven studies reported data on a hospital stay. The authors reported slightly shorter length of hospital stay, with a mean difference (95% CI [− 0.22, 0.8], P = 0.29) in the RRH group (5.14 d; n = 302) than in the LRH group (6.06 d; n = 308). Heterogeneity was detected (heterogeneity: χ2 = 20.42, df = 6 (P = 0.002);

I2 = 71%), and after applying a random-effects model to neutralize such heterogeneity, no valuable results were produced [Figure 4].
Figure 4: Forest plot of length of hospital stay

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Pelvic lymph nodes

Seven randomized RH studies reported pelvic lymph nodes. Heterogeneity was detected (heterogeneity: χ2 = 7.19, df = 6 [P = 0.30]; I2 = 17%), concerning I2 = 17%, far below 50%, the application of a random-effects model would not be used in the further study. Pelvic lymph nodes were not significantly different in the RRH (n = 304) group and in the LRH (n = 322) group (95% CI = − 1.87–1.70, P = − 0.99; [Figure 5]).
Figure 5: Forest plot of the number of pelvic lymph nodes

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Complications

Twelve randomized RH studies [12],[13],[17],[18],[20],[21],[22],[23],[24],[25] reported both intraoperative and postoperative complications.[12],[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27] Heterogeneity was detected (Heterogeneity: χ2 = 22.45, df = 11 [P = 0.02]; I2 = 51%), concerning I2 = 51%, slightly above 50%, the application of a random-effects model could be alternatively used. Since RRH group (n = 343 with 63 patients possessing complications) showed evident advantage over LRH group (n = 358 with 82 patients possessing complications), with a risk ratio of 1.31 (0.99, 1.74) [Figure 6]. Considering intraoperative/postoperative complication as a major bar to evaluate the clinical efficacy of the two techniques, we conducted further study under the dimensions of 5 intraoperative complication symptoms (vascular injury, pelvic bleeding, ureter-vaginal fistula, lymphorrhea, trocar hernia), and four postoperative items (urinary dysfunctions, bowel dysfunctions, vaginal cuff dehiscence, vaginal, and sex dysfunctions), within 6 of the 14 studies eligible.[12], 17, [22],[23],[24],[25] In general, RRH was characterized with higher complication rate (8.2%) comparing with LRH (7.4%). Among all the relevant symptoms, listed in [Table 2], vaginal cuff dehiscence was the most major contributor to complications in patients receiving RRH while pelvic bleeding was the most common complication in those undergone LRH. Based on the same size of population pool, overwhelming numbers of complication-possessed patients were observed in LRH group.
Figure 6: Forest plot of complications

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Table 2: Intraoperative and postoperative complications

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 > Discussion Top


LRH and RRH have become increasingly common in clinical practice,[3],[28] in large part because the procedure is thought minimally invasive surgery and thereby reducing postoperative morbidity compared to laparotomy.[9],[29] To examine whether RRH possesses an overwhelming advantage over LRH in surgical outcomes and intraoperative/postoperative complications, we performed a systematic meta-analysis of the literature comparing the clinical efficacy and complications of RRH and LRH based on laparotomy.[30],[31] Our findings support the results of individual studies indicating that RRH leads to less blood loss during the surgery and economical operating-room time. We also found RRH to be associated with lower risk of intraoperative/postoperative complications. These conclusions are consistent with at least two studies that we were unable to include in the meta-analysis because they focused only on RRH without LRH.[9],[29] In addition, the two approaches were generally similar with the respect of the length of hospital stay, with a mean difference 0.29 (− 0.22, 0.80) and the number of pelvic lymph nodes resected, with a mean difference − 0.09 (− 1.87, 1.70).

RRH is thought to be associated with better recovery and faster back to normal function,[32] yet we found little relevant data in the studies included in this analysis. Sert and Abeler reported a 3-year follow-up in 2011, from which we could deduced indirectly that patients undergone RRH might demonstrate better cause-free survival.[19] Unfortunately, we could not meta-analyze the data because there were three trials concerning 3 years follow-up of patients either undergone RRH or LRH, but reporting results in the form of divers recurrence patterns.

The results of our meta-analysis suggest that RRH characterized by fewer complications and potentially better postoperative life quality, especially in certain functional outcomes, than is LRH. We also attempted to figure out which surgical technique cherished larger extent of resection. After compared parametrical width and vaginal cuff length, proposed in one study published in 2007 by Sert and Abeler we found that there was no significant difference of feasibility between these two approaches.[20] Meanwhile, laparotomy showed the much larger extent of resection in practice even with a lot of disadvantages at the same time. However, the belief that RRH involves less extensive resection and, therefore, can lead to lower survival and a higher risk of recurrence proved to be irrational through a close look at three studies published by Soliman et al., Kim et al.[18],[34] and Sert and Abeler, respectively.[13],[19],[20] The reason why we did not include these findings on survival and recurrence was that they should be interpreted with caution for they come from individual studies of relatively limited statistical power, which could not be combined because of differences in study design and outcomes reporting.[33],[34]


 > Conclusion Top


This meta-analysis provides evidence for the belief that RRH is associated with low intraoperative/postoperative complications and good clinical efficacy for treating patients with early-stage cervical cancer, which has helped make it an increasingly popular clinical option. It appears to be competitive over LRH in terms of intraoperative blood loss. Many of these findings are based on a relatively small number of trials. Therefore, they should be verified in larger, multi-center pools in the future.

Acknowledgment

This work was supported by The "Nursery" program of Jining Medical College Affiliated Hospital (NO. MP-2014-001), Jining science and technology development plan and Wu Jieping Medical Foundation (NO. 320.6750.14079).

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
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