Mapping Sentinel Lymph Node in Initial Stages of Ovarian Cancer

The objective of this study is to know the lymphatic drainage and, if the lesion is malignant, remove the sentinel lymph nodes to know if it can predict the involvement of the remaining lymph nodes to assess the possible applicability of SLN in clinical practice. Study design: 1. Evaluation of the ovarian lymphatic map: injection of radiotracer (99mTc-nanocolloid albumin) in patients with a diagnosis of adnexal mass with high suspicion of malignancy. Intraoperative lymphogammagraphy will be performed using a portable gammacamera. Patients with a delayed diagnosis of ovarian cancer who are candidates to undergo a re-staging surgery will be included. 2. After the adnexectomy a frozen section will be performed to confirm the diagnosis of malignancy and then the ICG (Indocyanine green) tracer will be injected. Since the spread and persistence of the ICG in the lymph nodes is rapid, this tracer will be injected only after confirmation of EOC. Simultaneous screening with a gammadetector probe and NIR (near-infrared spectrum) camera will be used to proceed to the detection of SLN according to the lymphatic map previously. 3. Ultrastaging of the SLN by applying hematoxylin and eosin staining (H\&E) and, in the absence of metastatic disease, evaluation by immunohistochemistry with cytokeratin AE1: AE3.