Impact of sentinel lymph node mapping on recurrence patterns in endometrial cancer.

Background: Sentinel lymph node (SLN) mapping has emerged as a promising solution to the ongoing debate regarding lymphadenectomy in the initial surgical management of endometrial cancer. Currently, little is known about its possible impact on location of disease recurrence compared to systematic lymphadenectomy.

Methods: In this retrospective study, 472 consecutive patients with endometrial cancer who underwent either SLN mapping (SLN cohort, n=275) or systematic lymphadenectomy (LND cohort, n=197) from sequential, non-overlapping historical time points were compared. Clinical characteristics were extracted from a prospectively gathered electronic database. Both overall and pelvic sidewall recurrence free survival (RFS) were evaluated at 48-month post-operative follow-up.

Results: No significant difference in overall RFS could be identified between the cohorts at 48months (HR 0.74, 95% CI 0.43-1.28, p=0.29). However, the SLN cohort had improved pelvic sidewall RFS compared to the LND cohort (HR 0.32, 95% CI 0.14-0.74, p=0.007). The pelvic sidewall recurrences accounted for 30% of recurrences in the SLN cohort (8 out of 26 recurrences) compared to 71.4% in the LND cohort (20 out of 28 recurrences).

Conclusions: SLN mapping may enable more efficient detection of the LNs at greatest risk of metastasis and help to guide adjuvant therapy, which in turn seems to decrease the risk of pelvic sidewall recurrences.