Lymphatic mapping and sentinel lymph node detection in women with vaginal cancer

Objective: To determine the patterns of lymphatic drainage from primary vaginal cancers utilizing lymphoscintigraphy and to determine if this clinical information would affect treatment planning. Methods: For women with newly diagnosed vaginal cancer, pretreatment lymphatic mapping and sentinel lymph node identification were performed using lymphoscintigraphy. In patients who underwent surgery, sentinel lymph nodes were identified intraoperatively using radiocolloid and patent blue dye. The impact of pretreatment lymphoscintigraphy findings on radiation planning in women who received radiation as initial treatment was noted. Results: Fourteen women were enrolled during the study period. At least 1 sentinel lymph node was identified on pretreatment lymphoscintigraphy in 11 patients (79%). The median number of sentinel nodes found per patient was 2, and bilateral sentinel nodes were found in 6 (55%) of the 11 patients with sentinel nodes identified. Among these 11 patients, 5 (45%) had sentinel nodes identified in the groin only, 4 (36%) had sentinel nodes identified in the pelvis only, and 2 (18%) had sentinel nodes identified in both the groin and the pelvis. No relationship was observed between sentinel lymph node location and primary tumor histologic subtype or location. Three (33%) of the 9 women treated initially with radiation therapy had their radiation field altered as a result of the lymphoscintigraphy findings. Conclusion: In women with vaginal cancer, lymphatic drainage from the primary lesion does not always follow the lymphatic channels that would have been predicted anatomically. The addition of lymphoscintigraphy to the pretreatment evaluation for women with vaginal cancer may significantly improve comprehensive treatment planning.