FDG/PET-CT-Based Supraclavicular Lymph Nodes Atlas in Breast Cancer Patients from Two Central China Cancer Centers

Abstract

The aim of this study was to map the location of metastatic supraclavicular (SCV) lymph nodes in breast cancer patients with SCV node involvement by using positron emission tomography with fluorine 18 fluorodeoxyglucose/computed tomography (FDG-PET/CT). 107 patients with 370 FDG/PET-CT positive SCV lymph nodes metastases were included in our analysis. SCV lymph nodes areas were defined based on the main anatomical route of metastasis. All imaging data were imported into the planning system and each lymph node was manually contoured. A patient with “standard anatomy” was chosen as a template, and all contoured structures were registered rigidly and non-rigidly to this patient. A comprehensive atlas was delineated including all identified lymph node metastases. Further, the incidences of lymph node metastases were analyzed and are presented with color-coding in the atlas. A modified SCV CTV was proposed with better involved-node coverage. Of the 370 nodal metastases, 292(78.92%) were within the RTOG consensus volume, and 78(21.08%) in 33 patients were outside the volume. The highest rate of SCV lymph node metastasis was area II, and the lowest was area I. Supraclavicular disease outside the RTOG consensus volume was mostly located in area IV. The location of supraclavicular lymph nodes metastasis surpasses the range defined by the RTOG guidelines. We suggest the adjuvant irradiation target volume should be extended to cover area IV, particularly the posterior edge.