A direct endoscopic approach for left-sided infrarenal para-aortic lymphadenectomy immediately after hysterectomy for endometrial cancer treatment: left dome formation (LDF)

Abstract

Background: Endoscopic surgery for infrarenal para-aortic lymphadenectomy has been widely accepted. Two major approaches, "transperitoneal" and "extraperitoneal", are generally used; however, they have several disadvantages. A "transperitoneal" approach to the left para-aortic region is usually indirect, often performed after wide extension of the right para-aortic region. An "extraperitoneal" approach is unsuitable when a peritoneal tear exists after a prior surgical procedure such as hysterectomy. Here, we propose a modified transperitoneal technique, "Left dome formation (LDF)," which directly provides a surgical field for left infrarenal para-aortic lymphadenectomy even after hysterectomy.

Methods: The LDF procedure comprised three processes: (1) setting, (2) dissection of inframesenteric lymph nodes (step 1), and (3) dissection of infrarenal lymph nodes (step 2).

Setting: two trocars were added 4 cm bilateral to the low-mid abdominal trocar that was used in prior hysterectomy. Step 1: The posterior layer of the renal fascia along with the left ureter and left ovarian vessel were separated from the left common iliac artery and iliopsoas. Left inframesentric nodes were removed from the surgical field. Step 2: The left ureter was isolated from the posterior renal fascia, and the dome was expanded cranially to the left renal vein, with the ovarian vein always visualizable at the dome ceiling. Left infrarenal nodes were removed.

Results: We applied LDF to ten endometrial cancer patients, recommended for additional dissection of para-aortic nodes based on intraoperative evaluation using the laparoscopically removed uterus. The operative time and number of removed lymph nodes in Step 1 and Step 2 were 28.8 (20-49) min and 5.3 (2-10) and 54.6 (52-70) min and 6.5 (1-11), respectively. Blood loss was below 50 ml. No serious organ injury occurred during procedures.

Conclusion: Since the left ureter is always observable, LDF procedure facilitates effective surgery to overcome the anatomical complexity of the left para-aortic region and is potentially useful for sentinel node sampling.

Keywords: Direct access; Dome formation; Endometrial cancer; Left-sided infrarenal para-aortic lymphadenectomy; Sentinel node sampling.

Fig. 1

Setting for left dome formation procedure. A lithotomy position with 0°–10° head-down. Trocar Nos. 1, 3, 5, and 6 are introduced for hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymphadenectomy. Trocar Nos. 2 and 4 are added for the LDF procedure. The surgeon uses Nos. 1 and 3 for the procedure, No. 2 for the camera, and No. 4 for the endoretractor

Fig. 2

Step 1: Development of the dome for inframesenteric para-aortic lymphadenectomy. A Schema of anatomy for development of inframesenteric region. The posterior renal fascia is separated from the left common iliac artery and iliopsoas and forms the ceiling of the dome. B Surgical view of the dome. The ureter is visualized in the ceiling of the dome

Fig. 3

Step 2: Development of the dome for infrarenal para-aortic lymphadenectomy. A Schema of anatomy for the development of infrarenal para-aortic lymphadenectomy. The posterior renal facia is opened and the ureter is isolated dorso-laterally. B Surgical view after lymphadenectomy. The ovarian vein and connecting renal vein are visualized. The aberrant renal artery is also skeletonized safely