Abstract: We identified 1332 records as a result of the search (excluding duplicates). Of the 26 studies that potentially met the review criteria, we included four studies involving 205 women; most of the trials had unclear risks of bias. We identified one ongoing trial. The analysis of overall survival was not feasible, as there were no deaths reported among women allocated to standard radical hysterectomy. However, there were two deaths in among women allocated to the nerve-sparing technique. None of the included studies reported rates of intermittent self-catheterisation over one month following surgery. We could not analyse the relative effect of the two surgical techniques on quality of life due to inconsistent data reported. Nerve-sparing radical hysterectomy reduced postoperative bladder dysfunctions in terms of a shorter time to postvoid residual volume of urine ≤ 50 mL (mean difference (MD) -13.21 days; 95% confidence interval (CI) -24.02 to -2.41; 111 women; 2 studies; low-certainty evidence) and lower volume of postvoid residual urine measured one month following operation (MD -9.59 days; 95% CI -16.28 to -2.90; 58 women; 2 study; low-certainty evidence). There were no clear differences in terms of perioperative complications (RR 0.55; 95% CI 0.24 to 1.26; 180 women; 3 studies; low-certainty evidence) and disease-free survival (HR 0.63; 95% CI 0.00 to 106.95; 86 women; one study; very low-certainty evidence) between the comparison groups. Nerve-sparing radical hysterectomy may lessen the risk of postoperative bladder dysfunction compared to the standard technique, but the certainty of this evidence is low. The very low-certainty evidence for disease-free survival and lack of information for overall survival indicate that the oncological safety of nerve-sparing radical hysterectomy for women with early stage cervical cancer remains unclear. Further large, high-quality RCTs are required to determine, if clinically meaningful differences of survival exist between these two surgical treatments.

Plain-language summary: We found four small studies that compared nerve-sparing radical hysterectomy versus standard radical hysterectomy. None of the included studies reported data on overall survival and rate of intermittent self-catheterisation (procedure in which patient periodically inserts a small tube (catheter) through the urethra into the bladder to empty it of urine) over one month following surgery. We could not assess the relative effect of these two operations on quality of life due to inconsistent data reported. Women undergoing nerve-sparing radical hysterectomy had better voiding (a technique of bladder training in which the woman is instructed to urinate according to pre-determined schedules) functions following surgery than those undergoing standard radical hysterectomy. We found no evidence that women undergoing nerve-sparing radical hysterectomy were more likely to have adverse consequences of surgery or relapse of their cancer. The certainty of the evidence is therefore low or very low. Nerve-sparing radical hysterectomy may reduce the chance of bladder dysfunction compared to standard radical hysterectomy. However, the certainty of this evidence is low and further studies have the potential to better inform this outcome. We are very uncertain as to whether nerve-sparing radical hysterectomy is safe in terms of cancer survival outcomes. The evidence of cancer recurrence was of very low-certainty, there were no long term data available regarding risk of death from cancer or other causes. High-quality international studies involving many women would be needed to tell us whether nerve-sparing radical hysterectomy is beneficial in terms of survival for women with early stage cervical cancer, since risk of recurrence in this group are low.