ABSTRACT
There are different lymphatic drainage pathways in the thorax that are relevant in the staging of lung cancer, breast cancer, lymphoma, esophageal cancer, and malignant mesothelioma. To properly search for metastatic spread, it is important to carefully evaluate the specific nodal stations that drain the thoracic structures from which a primary tumor originates. Because size criteria have limitations in the prediction of nodal status, pathologic confirmation is essential for accurate staging. Computed tomography (CT) is useful in helping the surgeon or interventional radiologist determine the most appropriate approach for nodal sampling. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has an increasing role in detection of diseased lymph nodes that appear normal at CT alone, particularly when FDG PET images are fused with CT images. However, the role of radiologic imaging extends beyond initial staging and the guidance of interventions to include posttreatment assessment and the detection of recurrent disease. Therefore, at all levels of cancer imaging, it is essential to identify the relevant lymph node regions and their relations to the primary tumor.
Subject(s)
Lymphatic Metastasis/diagnostic imaging , Thoracic Neoplasms/diagnostic imaging , Tomography, X-Ray Computed , Aged , Breast Neoplasms/diagnostic imaging , Carcinoma/diagnostic imaging , Carcinoma/secondary , Esophageal Neoplasms/diagnostic imaging , Female , Fluorodeoxyglucose F18 , Humans , Lung Neoplasms/diagnostic imaging , Lymphoma/diagnostic imaging , Male , Mediastinum , Mesothelioma/diagnostic imaging , Mesothelioma/secondary , Middle Aged , Neoplasm Staging/methods , Pleural Neoplasms/diagnostic imaging , Radiography, Interventional , Radiopharmaceuticals , Tomography, Emission-ComputedABSTRACT
The purpose of this set of 2 articles is to illustrate the source and direction of lymphatic drainage in the thorax on axial computed tomographic (CT) schematics. The first article describes the upper thorax. This article describes the lower thorax. The nodal groups are given conventional anatomic names and the corresponding terminology of the American Thoracic Society. Arrows indicate the direction of the flow. The region or organ drained is color-coded, and nodes that receive lymph from each area are assigned appropriately colored and numbered boxes. Major drainage patterns are also described. This information can be used to assess a suspicious lymph node by tracing it to the region of drainage and looking for pathology. Alternately, one may extrapolate the potential drainage routes of a tumor and scrutinize specific sites for nodal metastases.
Subject(s)
Lung Neoplasms/pathology , Lymphatic Metastasis/diagnostic imaging , Lymphatic System/anatomy & histology , Thorax/anatomy & histology , Tomography, X-Ray Computed , Humans , Lymphatic Metastasis/pathology , Reference ValuesABSTRACT
The purpose of this set of two articles is to illustrate the source and direction of lymphatic drainage in the thorax on axial CT schematics. The first article describes the upper thorax. The second article will describe the lower thorax. The nodal groups are given conventional anatomic names and the corresponding terminology of the American Thoracic Society. Arrows indicate the direction of the flow. The region or organ drained is color-coded, and nodes that receive lymph from each area are assigned appropriately colored boxes. Major drainage patterns are also described. This information can be used to assess a suggestive lymph node by tracing it to the region of drainage and looking for pathological lesions. Alternatively, one may extrapolate the potential drainage routes of a tumor and scrutinize specific sites for nodal metastases.
