Extent of disease is determined by positron emission tomography/computed tomography (PET/CT) for avid lymphomas and CT for nonavid histologies. Tonsils, Waldeyer's ring, and spleen are considered nodal tissue.
Reproduced with permission from Wolters Kluwer Health, Inc.: Cheson BD, Fisher RI, Barrington SF, et al. Recommendations for initial evaluation, staging, and response assessment of Hodgkin and non-Hodgkin lymphoma: The Lugano classification. J Clin Oncol 2014; 32(27):3059-67. Copyright © 2014 American Society of Clinical Oncology.
https://ascopubs.org/journal/jco.