New nodal, extranodal and assessable sites of disease should be reported when present. In accordance with the IWG-NHL guidelines:
- A new node must be >1.5 cm in any axis to be considered a new lesion.
- An extranodal lesion must be >1.0 cm in any axis to be considered a new lesion.
- An assessable site of disease of any size can be considered a new lesion provided it is unequivocally attributable to lymphoma and is confirmed by another method such as FDG-PET, biopsy, cytology or other non-radiologic verification to confirm the disease is attributable to NHL.