Topographic distribution of sentinel lymph nodes in patients with cervical cancer.

BACKGROUND

Since the introduction of the sentinel concept in cervical cancer in 1999, various studies have been demonstrated the feasibility, detection rate and sensitivity and rate of false-negative sentinel lymph nodes (SLN). There are only limited data regarding the mapping of the removed SLN. A correlation between the localization of SLN and the tumor stage, histology or marker substance has never been investigated.

METHODS

Between 2/2000 and 6/2005, the SLN distribution of 151 patients with histologically confirmed cervical cancer (FIGO stages IA n = 21, IB n = 95, IIA n = 14, IIB n = 18, IIIB n = 2, IVA n = 1), who participated in the ongoing "Uterus 3" sentinel study of the German Association of Gynecologic Oncologists (AGO), was retrospectively analyzed with respect to the histology, tumor stage and detection substance. The tumors comprised mostly of squamous cell carcinomas (75.5%) with a smaller fraction of adenocarcinomas (24.5%).

RESULTS

Altogether, 406 SLN, an average of 2.7 (1-7) SLN per patient, were removed. More than one SLN was detected in 111 patients (73.5%). SLN were found unilaterally in 70 patients (46.4%) und bilaterally in 81 patients (53.6%). SLN sites were paraaortic in 4%, common iliac in 5%, external iliac in 5%, internal iliac in 8%, interiliac in 71% and parametric in 7%. Irrespective of the detection drug applied, most SLN were interiliac (blue 70%, TC 67%, TC and blue 71%). Combined application of technetium and blue dye revealed significantly more SLN in the paraaotic region (P = 0.006). Adenocarcinomas and squamous carcinomas did not differ in the distribution of SLN (P = 0.205). The majority of SLN are interiliac in all tumor stages (FIGO IA 76%, IB 68%, IIA 61%, IIB 83%, III and IV 88%).

CONCLUSIONS

Removal of SLN in the external iliac, interiliac and obturator area enables evaluation of more than 80% of all SLN. The pattern of SLN is independent from histology and tumor stage. Combined use of technetium and blue dye detects sentinels more frequently in the paraaortic region than a single marker.