Added-value of SPECT/CT in Patients Undergoing LM/SL for Gynecological Cancers

Nodal staging is a key-step in pre-treatment assessment of gynecological cancers. In recent years, lymphatic mapping and sentinel lymphadenectomy (LM/SL) as a minimally invasive pelvic lymph nodes staging has been successfully evaluated in women with early stage of vulvar cancer, cervical cancer, and endometrial cancer. Such a technique may offer several valuable advantages: a) it is readily applicable in clinical routine using a safe, inexpensive, and reproducible protocol; b) it may help to avoid the cost and the morbidity of unnecessary lymphadenectomy in the majority of cases with uninvolved sentinel lymph nodes; c) it has the potential to guide the surgeon to nodal regions that are not routinely dissected (i.e. pre-sacral, para-aortic nodes) and to identify micro-metastases that would have been ignored otherwise; d) it also offers the basis for sophisticated pathological analysis to detect sub-microscopic nodal metastases using either immunohistochemical or molecular biological techniques. So far, within the abdomen and the pelvis, the LM/SL technique alone is often blinded to the accurate localization of SLNs. The integration of computed tomography (CT) to single photon emission computed tomography (SPECT) devices in a single gantry (SPECT/CT) has allowed a significant gain in terms of diagnostic accuracy and anatomic precision; clinical examples include malignant melanoma, head and neck cancer, breast cancer, and bladder cancer. In a seminal series of 26 patients with cervical cancer (Zhang et al., 2006), SPECT/CT was recently found superior to conventional planar imaging for detection of SLN and accurate localization. A more recent study (Kushner al., 2007) has also highlighted the technical feasibility and the clinical added-value of a low-dose SPECT/CT in a series of 20 patients with early stage cervical cancer (IA2-IIA) who underwent LM/SL. In the light of the encouraging data from literature and our own preliminary clinical experience, we hypothesized