Sentinel Lymph Node Detection in Early Cervical Cancer
Condition: Cervical Cancer
MeSH terms: Uterine Cervical Neoplasms
Study type: Interventional

Summary: 
      The primary objective of this study is to determine the feasibility of detecting the sentinel
      lymph node (SLN) in patients with early invasive cervical cancer using a combined
      radioisotope and blue dye technique.

      The investigators hypothesize that the sentinel lymph node (first node draining the
      tumour/cervix) for early stage cervical cancer represents the status of the regional lymph
      node basin (pelvic lymph nodes) and identification of a negative SLN would negate the need
      for complete pelvic lymphadenectomy.
    

Detailed description: 
      Cancers of the cervix that are small and appear to be contained in the cervix (early stage)
      have up to 20 percent chance of having pelvic lymph nodes involved. The standard therapy is
      removal of the uterus and cervix (radical hysterectomy) and removal of all pelvic lymph nodes
      for all women with early stage cervical cancer. This procedure can be associated with
      significant intraoperative and postoperative complications including increased risk of damage
      to blood vessels and nerves in the pelvic region (leading to bladder, bowel and sexual
      dysfunction) as well as lymphedema (swelling, particularly in the legs) associated with
      significant pelvic lymph tissue removal.

      The objective of this study is to find a way to accurately identify the first lymph node that
      drains the tumour/cervix (SLN). If this SLN is correctly identified, and it's status
      (positive or negative for malignancy) is representative of the entire lymph node basin, a
      complete node dissection could be avoided. This could benefit many women with early stage
      cervical cancer, as a minority actually have evidence of disease in the nodes after surgery
      (between 5-20%) and limited lymph node sampling could prevent the associated complications of
      a full pelvic lymph node dissection.

      This is a prospective cohort study. The population to be studied is patients with newly
      diagnosed early stage cervical cancer undergoing primary surgical intervention including
      radical hysterectomy and bilateral pelvic lymphadenectomy. On the morning of surgery,
      preoperative injection of a radiolabeled colloid will be performed in the Nuclear Medicine
      Department followed by SPECT/CT to visualize the radiolabelled dye. Patients will then be
      taken to the operating room for their planned procedure. After initiation of general
      anesthesia, blue dye will be injected into the patient's cervix. The surgery will proceed and
      all lymph nodes that are "blue" and/or "hot" will be removed surgically, their anatomic
      location and laterality documented and sent for frozen section intraoperatively. The radical
      hysterectomy or radical trachelectomy and complete systematic bilateral pelvic
      lymphadenectomy will then be performed. The SLN status reported by the pathologist based on
      the frozen section will be compared to the status of the other nodes removed after complete
      lymphadenectomy and reported in the final pathology report (after formalin fixation and
      paraffin embedding). All data on these patients will be prospectively collected.

      This protocol will determine the feasibility of SLN mapping in women with early stage
      cervical cancer. The primary outcomes will be to measure the rate of detection of SLN using
      the combination of radiolabelled and blue dye (unilateral and bilateral detection rates will
      be reported) as well as the sensitivity and specificity of this technique, based on assessing
      how well the intraoperative reading of SLN frozen section corresponds with the final
      pathology lymph node status after examining all lymph nodes removed by complete pelvic
      lymphadenectomy.

      In addition, the investigators will assess the usefulness of preoperative SPECT/CT in
      identifying SLN and whether this modality accurately identifies the lymph node basin
      containing SLN compared to conventional lymphoscintigram.
    

Intervention name(s): Preoperative and intraoperative SLN Mapping
Intervention type(s): Procedure
Intervention description(s): Patients will undergo preoperative SLN mapping, which includes an injection of a radiocolloid and lymphosinctogram and SPECT/CT. Patients will also receive an intraoperative injection of blue dye. A handheld probe will be utilized to detect radiolabelled or "hot" nodes and direct visualization will identify blue nodes which will be labelled "Sentinel Nodes" and sent to pathology for intraoperative frozen section.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Cervical Cancer; Sentinel Lymph Node; Lymphadenectomy