Treatment of stage IA NLPHL of the right neck with IFRT vs ISRT. Diagnostic PET-CT scout (A), coronal (B), and axial (D) images of a patient with fluorodeoxyglucose-avid stage IA NLPHL of the right neck treated with IFRT. Coronal (C) and axial (E) CT images from the 3-dimensional radiation treatment plan illustrate the gross disease (contoured in red) and the extended clinical treatment volume (contoured in yellow). Diagnostic PET-CT scout (F), coronal (G), and axial (I) images of a second patient with stage IA NLPHL of the right neck treated with ISRT. Coronal (H) and axial (J) images from the RT plan illustrate the gross tumor volume (contoured in red) and the more limited clinical tumor volume (contoured in yellow).