Sentinel lymph node biopsy in endometrial and cervical cancers using freehand SPECT—first experiences

The sentinel lymph node (SLN) biopsy (SLNB) is currently being developed for uterine cancers. The uterus is not easily accessible for tracer application; furthermore, the lymphatic drainage of the uterus is complex, which makes laparoscopic localization of the SLN challenging. The freehand single photon emission computed tomography (SPECT) is a 3D laparoscopic imaging modality which has been developed to overcome these problems. The aim of the study was to evaluate the freehand SPECT to detect the SLN in patients with uterine cancers. Twenty-nine patients with endometrial or cervical cancers were included into the LAPSENT study. Freehand SPECT was utilized to detect the SLN and guide its resection following intracervical injection of the tracer in patients with cervical cancer or hysteroscopy-guided injection of the tracer in patients with endometrial cancers. SLNs were detected in 18 of 24 patients with endometrial cancer and in 5 of 5 patients with cervical cancer. An average of 1.1 SLNs was detected in patients with endometrial cancers and 2 SLNs in patients with cervical cancers. The SLN was located in the pelvic lymphatic basin in 16 patients (12 unilateral and 4 bilateral). Three patients had paraaortic SLNs. Only one metastasis was found in any of the SLNs removed (endometrial cancer case) resulting in an upstaging. We demonstrated that SLNB in endometrial and cervical cancers using the freehand SPECT is feasible and that hysteroscopy-guided injection of the tracer is reasonable in endometrial cancers. Combining both techniques single-anesthesia SLNB of endometrial cancer is feasible.