Value and best way for detection of Sentinel lymph node in early stage endometrial cancer: Selective lymphadenectomy algorithm.

INTRODUCTION

The cornerstone of treatment for endometrial carcinoma is total abdominal hysterectomy and bilateral salpingo-oophoprectomy. Pelvic lymphadenectomy, with or without para-aortic lymphadenectomy, plays an important role in the surgical staging of endometrial carcinoma, and provides more accurate prognostic information.

AIMS

We aimed to evaluate the value and techniques for SLN mapping in early stage endometrial cancer with low risk for lymph node metastasis and whether selective or systematic lymphadenectomy is needed according to the results of proposed algorithm.

METHOD

Between June 2016 and June 2017, 120 patients with early stage endometrial cancer with low risk for nodal metastasis underwent surgical staging. Patients were classified equally according to SLN mapping technique used for injecting the methylene blue dye. Group A included hysteroscopic guided methylene blue injection, Group B included transcervical injection, Group C included subserosal uterine injection and Group D included combined transcervical and subserosal injection. Blue lymph nodes and enlarged suspicious whether stained or non stained ones were dissected for frozen section evaluation done then bilateral pelvic node dissection was done and tissues were sent for pathological examination.

RESULTS

Clinical and pathological SLN detection were more with hysteroscopic technique than others and pathological detection was lower than clinical detection in all techniques. Metastatic disease was more common in nodes with suspicious appearance. About 10% of negative suspicious and mapped nodes were associated with positive other nodes for metastasis.

CONCLUSION

SLN in endometrial cancer has a role in staging of endometrial cancer with best technique for detection, hysteroscopic guided blue dye injection. SLN can be used in patients with low risk for lymph node metastasis for selective lymphadenectomy. Blue dye labelling using methylene blue dye is good in low resource countries as it is cheap. We recommended the following algorithm for surgical staging in early endometrial cancer with better results than using SLN alone. Stage I type 1, grade 1,2 endometrial cancer should undergo surgical staging with initial evaluation of the peritoneum which if affected, it is stage III with no need for lymphadenectomy. Then, dissection of the blue and suspicious nodes which if any is positive on frozen section, selective same side pelvic and paraaortic nodal dissection should be done. If they are negative, no need for lymphadenectomy. This approach can help patients to avoid the side effects associated with a complete lymphadenectomy. The higher rate of detection using this algorithm is related to combining the suspicions nodes with the stained ones.