Sentinel Lymph Node in Early-Stage Endometrium Cancer

The aim of this prospective study is to investigate whether the detection rate of sentinel lymph node (SLN) with double tracer injected at two different sites may be increased compared to the standard use of a single tracer with single site (cervix) injection in early-stage endometrial cancer.

Endometrial cancer is the most common gynecologic cancer. Although 85-90% of women are diagnosed at early stage, about 10-15% are diagnosed at advanced stages. Treatment and prognosis depends on the surgical staging of the apparently early stage disease including the evaluation of lymphatic status of the disease. Detection of positive lymph node upstages the apparently early stage endometrial cancer. However, systematic lymphadenectomy carries immediate and long term risks for patients including bleeding, massive transfusions, prolongation of operation time, serious major vessel and major abdominal organ injury and death. These risks are especially increased in para-aortic lymphadenectomy which is a part of staging procedure in apparently early stage endometrial cancer.

Sentinel lymph node biopsy (SLNB) procedure is the biopsy of one or two lymph node(s) which represents the lymph node basin draining the area of malignancy. This biopsy may potentially eliminate the need systemic pelvic / para-aortic lymphadenectomy which harbours potential complications. Although SLNB became an standard procedure in endometrial cancer, available data on the SLNB in endometrial cancer is variable. The relevant literature suggests that the detection rate of sentinel lymph node using various tracer agents are between %70-98, even with lower for bilateral pelvic detection and para-aortic sentinel lymph node(s). The most commonly used tracer agents are methylene blue, radiolabeled colloid technetium 99 (Tc99), isosulfan blue and fluorescent indocyanine green. Although subserosal, intramyometrial uterine injections and peritumoral injections using hysteroscopy with different tracers and different detection rates have been used, cervical injection with ICG is the most favoured and standard technique with highest pelvic SLN detection rates. However, the para-aortic SLN detection rates are not satisfactory with a single tracer injected into cervix which may be critical especially in high grade endometrioid, serous and clear cell histological types.

So, investigators aimed to investigate whether the sentinel lymph node detection rates may be improved with double tracer injected at two different sites (charcoal carbon black dye injected in subserosa and ICG injected into cervix) compared to standard single tracer injected in early-stage endometrial cancer, especially the para-aortic sentinel lymph nodes. Sterile charcoal carbon black dye is an agent previously used for sentinel lymph node detection in various cancers such as breast cancer.

Technically, 2 mL indocyanine green with sterile water is injected at 3 and 9 o'clocks (each 1 mL) of cervix before the start of laparoscopic operation. Additionally, 2-4 mL of sterile charcoal carbon black dye is carefully injected just beneath the serosal layer at uterine fundus bilaterally avoiding intravascular injection This is done classically during laparoscopy by a spinal needle introduced under optical supervision after all optical and operative instruments are entered. 10-15 minute interval is allowed before the start of harvesting sentinel lymph nodes in pelvic and paraaortic region.

Eligibility Criteria:
Inclusion Criteria:

1. Must have preoperative histologic diagnosis of endometrial carcinoma
2. Must be in early stage ( stage1 and 2) endometrial carcinoma radiologically and clinically
3. Must have written informed consent

Exclusion Criteria:

1. Possible allergic reaction to commonly used drugs
2. Medical or surgical contraindications for comphrensive staging
3. Preoperative or intraoperative findings of advanced endometrial cancer