Skipping the Uterine Manipulator Cuts Blood Loss in Single-Port Hysterectomy Study

Surgeons at Sun Yat-sen University Cancer Center in China report that a hysterectomy technique that dispenses with the uterine manipulator—a rod-like device inserted through the cervix to hold and reposition the uterus during laparoscopic surgery—was feasible in single-port laparoscopic hysterectomy and was associated with less intraoperative bleeding than the conventional manipulator-assisted approach. The findings, published in Holistic Integrative Oncology, come from a retrospective cohort study of 190 patients operated on between January 2022 and July 2025, and they arrive amid lingering controversy over whether uterine manipulation may compromise oncological safety in minimally invasive gynecological cancer surgery.

The concern is not trivial. After the Laparoscopic Approach to Cervical Cancer (LACC) trial found that minimally invasive surgery for cervical cancer was associated with worse survival than open surgery, researchers began scrutinizing every element of the laparoscopic technique, including the manipulator. Hypothesized risks include mechanical compression of the tumor and intraperitoneal exposure of tumor tissue. Population-based studies cited by the authors estimate uterine perforation rates of up to 11 percent during manipulator insertion, an event that could theoretically carry iatrogenic tumor dissemination risk. The problem is compounded by anatomy: placing a manipulator requires aligning its cup and shaft with the uterine cavity, which becomes difficult with fibroids, adenomyosis, cavity distortion, or intrauterine adhesions. A survey referenced in the study found that 47.4 percent of initial manipulator placements in teaching hospitals were performed by residents, and 54.6 percent were done without direct laparoscopic visualization.

Single-port laparoscopic hysterectomy amplifies these challenges. In this approach, all instruments pass through a single umbilical incision, typically 2 to 3 centimeters long, using a four-channel platform. The coaxial arrangement of instruments and the limited ability of an assistant to triangulate make intraoperative adjustment of uterine position less forgiving than in conventional multiport surgery. Existing manipulator-free alternatives have drawbacks of their own: suprapubic suspension techniques require suturing the uterine fundus, which may violate the no-touch principle valued in endometrial cancer surgery, and they demand additional operative sites that increase instrument crowding.

The new technique, developed after the surgical team encountered manipulator-related adverse events including uterine perforation and tumor spillage, replaces the device with surgeon-controlled traction. The lead surgeon grasps the round ligament or broad ligament stump with dissecting forceps in the left hand, providing continuous, dynamically adjustable uterine traction without an assistant. For the vesicouterine space, the surgeon elevates the uterus with one hand while dissecting with an ultrasonic scalpel in the other, using the blade tip to gently push the bladder caudally under pneumoperitoneum pressure. The uterine artery is sealed with bipolar coagulation applied 1.0 to 2.0 centimeters lateral to the cervix and then transected. Before circumferential colpotomy, the vagina is packed with gauze to reduce pneumoperitoneum leakage and help delineate the vaginal fornix by tactile feedback. A 25 by 25 centimeter gauze pad inserted through the umbilical incision, combined with Trendelenburg positioning, displaces the bowel cranially and maintains a stable pelvic field.

The study included patients undergoing single-port laparoscopic hysterectomy for both benign and malignant gynecological diseases, with no exclusion criteria applied. Of the 190 patients, 88 underwent manipulator-free surgery and 102 manipulator-assisted surgery, all performed by the same surgical team. The groups were broadly comparable in age, performance status, body mass index, uterine dimension, and surgical history, but malignant disease was more frequent in the manipulator-free group (81.8 percent versus 65.7 percent), and the most complex level III procedures—such as radical hysterectomy or lymphadenectomy—were also more common there (51.1 percent versus 34.3 percent).

Despite facing ostensibly harder cases, the manipulator-free group showed markedly better hemostatic outcomes. Mean intraoperative blood loss was 70.6 milliliters compared with 103.6 milliliters in the manipulator-assisted group, and fewer patients lost 100 milliliters or more. Postoperative declines in hemoglobin (9.6 versus 14.5 grams per liter) and albumin (6.8 versus 10.5 grams per liter) at 24 hours also favored the manipulator-free approach. Because the groups were not randomized, the researchers applied propensity score matching on surgical complexity, benign or malignant status, body mass index, and uterine volume, successfully matching 70 pairs with all baseline characteristics balanced. The blood loss advantage persisted in the matched cohort (56.4 versus 98.6 milliliters) and in multivariable linear regression, which estimated an independent reduction of 39.1 milliliters associated with the manipulator-free technique after adjusting for surgical complexity, disease status, body mass index, and uterine dimension.

The most striking safety difference was uterine perforation, which occurred in 10 cases, all in the manipulator-assisted group, versus none in the manipulator-free group. Seven of the perforation cases involved malignancy, but the affected patients spanned heterogeneous diagnoses and anatomical backgrounds, including fibroids, adenomyosis, enlarged uteri, and prior pelvic surgery. The authors are careful on this point: the data show that perforations occurred only where a manipulator was inserted, and that eliminating the insertion step eliminates perforations related to that step, but they do not prove that every perforation is caused solely by the device.

On efficiency, no patient in either group required conversion to laparotomy or additional trocars, and none in the manipulator-free group converted to the manipulator-assisted approach. Overall operative time was statistically comparable between groups, though the authors caution that operative duration is strongly influenced by concurrent procedures and evolving team experience. The hysterectomy portion itself averaged 35.4 minutes in the manipulator-free group, and cumulative sum analysis indicated proficiency was reached after approximately the first 15 cases—a short learning curve for a novel single-port procedure. Postoperative recovery measures, including time to first flatus, time to ambulation, pain scores, hospital stay, and Clavien-Dindo complication rates, were similar between groups, with all complications being grade I or grade II.

Short-term oncological indicators showed no adverse signal for the new technique. Among patients with malignant disease, rates of positive peritoneal lavage cytology were 9.7 percent in the manipulator-free group versus 16.4 percent in the manipulator-assisted group, a difference that did not reach statistical significance, and lymphovascular space invasion rates were similarly comparable at 11.1 percent versus 14.9 percent. During a median follow-up of 20 months, two patients with endometrial cancer, one in each group, developed distant recurrence. The authors emphasize that these short-term indicators should be read as an absence of harm signal rather than evidence of oncological benefit, and that long-term outcomes remain to be validated; they plan follow-up of at least three to five years focusing on recurrence-free and overall survival.

The study has limitations the authors acknowledge directly. It was a retrospective, single-center comparison with all procedures performed by one experienced team, so temporal bias may have influenced the findings as the team accumulated single-port experience over time, and residual confounding from unmeasured factors cannot be excluded. The proposed mechanisms for the bleeding advantage—avoidance of endometrial irritation, relaxation of parametrial tissue in the absence of manipulator-induced tension, and real-time surgeon-controlled exposure—remain hypothesis-generating, since tissue tension and energy parameters were not prospectively recorded. Still, for a procedure in which device insertion is itself a recognized hazard, the message is pragmatic: a technique that removes the manipulator, avoids perforations tied to its insertion, shortens the learning curve to roughly 15 cases, and was associated with roughly 40 milliliters less blood loss may offer surgeons treating early-stage gynecological malignancies a credible no-touch alternative, provided its oncological equivalence is confirmed in longer follow-up and, ideally, in studies beyond a single surgical team.

Subject of Research: A manipulator-free technique for single-port laparoscopic hysterectomy evaluated in a retrospective propensity score-matched cohort study

Article Title: Manipulator-free technique for single-port laparoscopic hysterectomy avoids uterine perforation and reduces blood loss: a propensity score-matched study

Article References: Lin, Z., Gu, H., Liu, G., Liu, Z., Chen, J., & Tu, H. (2026). Manipulator-free technique for single-port laparoscopic hysterectomy avoids uterine perforation and reduces blood loss: a propensity score-matched study. Holistic Integrative Oncology, 5(1), Article 85. https://doi.org/10.1007/s44178-026-00308-2

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00308-2

Keywords: single-port laparoscopy, hysterectomy, uterine manipulator, gynecological cancer, blood loss, uterine perforation, propensity score matching, learning curve, endometrial cancer, surgical technique, LACC trial, minimally invasive surgery