Definition of compartment-based radical surgery in uterine cancer: modified radical hysterectomy in intermediate/high-risk endometrial cancer using peritoneal mesometrial resection (PMMR) by M Höckel translated to robotic surgery

Abstract

Background: The technique of compartment-based radical hysterectomy was originally described by M Höckel as total mesometrial resection (TMMR) for standard treatment of stage I and II cervical cancer. However, with regard to the ontogenetically-defined compartments of tumor development (Müllerian) and lymph drainage (Müllerian and mesonephric), compartments at risk may also be defined consistently in endometrial cancer. This is the first report in the literature on the compartment-based surgical approach to endometrial cancer. Peritoneal mesometrial resection (PMMR) with therapeutic lymphadenectomy (tLNE) as an ontogenetic, compartment-based oncologic surgery could be beneficial for patients in terms of surgical radicalness as well as complication rates; it can be standardized for compartment-confined tumors. Supported by M Höckel, PMMR was translated to robotic surgery (rPMMR) and described step-by-step in comparison to robotic TMMR (rTMMR).

Methods: Patients (n = 42) were treated by rPMMR (n = 39) or extrafascial simple hysterectomy (n = 3) with/without bilateral pelvic and/or periaortic robotic therapeutic lymphadenectomy (rtLNE) for stage I to III endometrial cancer, according to International Federation of Gynecology and Obstetrics (FIGO) classification. Tumors were classified as intermediate/high-risk in 22 out of 40 patients (55%) and low-risk in 18 out of 40 patients (45%), and two patients showed other uterine malignancies. In 11 patients, no adjuvant external radiotherapy was performed, but chemotherapy was applied.

Results: No transition to open surgery was necessary. There were no intraoperative complications. The postoperative complication rate was 12% with venous thromboses, (n = 2), infected pelvic lymph cyst (n = 1), transient aphasia (n = 1) and transient dysfunction of micturition (n = 1). The mean difference in perioperative hemoglobin concentrations was 2.4 g/dL (± 1.2 g/dL) and one patient (2.4%) required transfusion. During follow-up (median 17 months), one patient experienced distant recurrence and one patient distant/regional recurrence of endometrial cancer (4.8%), but none developed isolated locoregional recurrence. There were two deaths from endometrial cancer during the observation period (4.8%).

Conclusions: We conclude that rPMMR and rtLNE are feasible and safe with regard to perioperative morbidity, thus, it seems promising for the treatment of intermediate/high-risk endometrial cancer in terms of surgical radicalness and complication rates. This could be particularly beneficial for morbidly obese and seriously ill patients.

Figure 1

Right infundibulopelvic ligament. Arteria ovarica and vena ovarica, the border to the right colon mesentery, and the lymphatic anastomosis to the right inframesenteric periaortic lymph nodes (arrows) are visible.

Figure 2

The structures of the female genital tract with reference to the embryologic Müllerian and mesonephric compartment. The accordant structures resected in endometrial cancer are colored dark green for the Müllerian Compartment (a) and blue for the mesonephric lymphatic drainage (b), ovarian and infundibulopelvic system). The parts of the Müllerian compartment that are only resected in stage II or III disease are colored light green. Modified from Höckel [14] and Hepp et al.[15], with permission of Elsevier and Urban & Schwarzenberg, respectively.

Figure 3

Separation of the right infundibulopelvic ligament from the right mesocolon and dissection of connecting vessels.

Figure 4

Mobilization of the right infundibulopelvic ligament from laterally to medially and resection together with adherent periaortic nodes ventrally of the vena cava. The ureter and the vessels supplying the mesureter are preserved and mobilized.

Figure 5

Dissection of the ovarian artery and ovarian vein, at the aortic and cava level, respectively. The right periaortic nodes are left attached and represent the first draining nodes (compare to Figure  2b).

Figure 6

Same preparation of the left side. Following dissection of the ovarian vessels at their aortic and renal origin on the left, the infundibulopelvic ligament is dissected from the left mesocolon and followed through a prepared channel dorsally to the mesosigmoid. The left infrarenal periaortic nodes are kept in continuity to the ovarian vessel system as shown on the right.

Figure 7

Transferral of the left infundibulopelvic ligament. Following complete mobilization, the left infundibulopelvic ligament is pulled through the sigmoid ‘tunnel’ to the pelvis together with the left infrarenal periaortic nodes, to guarantee complete resection of the mesonephric ovarian drainage and avoiding division of the ligament.

Figure 8

Preparation of vascular anastomoses of the uterine and ovarian vessel system containing the accordant lymph drainage. Lateral peritoneal incision with preparation of the lateral aspect of the vascular mesometrium and division of the round ligament.

Figure 9

Ventral incision line to preserve the peritoneal covering the uterine and ovarian vessel system ensures complete resection.

Figure 10

Dorsal incision line caudally of the uterine vessels identified through the intact peritoneum.

Figure 11

Specimen of the uterus (ventral aspect) following rPMMR and rtLNE, showing the completely resected uterine and ovarian vessel system, without separation of connecting vessels and surrounding tissue. The uterine and ovarian pathways of lymph drainage are indicated by arrows. rPMMR, robotic peritoneal mesometrial resection; rtLNE, therapeutic lymphadenectomy.

Figure 12

Same specimen of the uterus (dorsal aspect) together with the pelvic nodes, kept in continuity with the uterine drainage system.