ABSTRACT
The assessment of lymph nodes is an essential component of the application of multidetector computed tomography (CT) in oncology, both in the detection of metastatic disease within the locoregional lymph nodes draining a tumor, and in the assessment of lymphoma. The main criterion used in conventional CT assessments comprises a measurement of nodal size, although other morphological features such as shape and texture, and the appearances of nearby nodes, may also contribute. However, the limitations of this morphological approach are well recognized. For example, lymph nodes that contain tumor may be smaller than the cut-off size used for the diagnosis of involvement. On the other hand, lymph nodes may be enlarged yet be reactive rather than contain tumor cells. Lymph nodes may also remain enlarged despite successful treatment (see Figure 10.5). Furthermore, interobserver variation in the measurement of lymph node size creates significant potential for misclassification.1
