Extent of disease among the ATL patient cohort. CT slices in the sagittal (A) and axial (B) planes of a patient with leptomeningeal disease. (C) CT slice in the axial plane of a patient with extensive cervical neck lymphadenopathy. The patient was treated with a right anterior oblique and left posterior oblique photon beam arrangement to gross adenopathy, contoured in red, with radiation isodose lines also depicted (green indicates 102% of the prescribed dose; red, 100%; yellow, 99%; lavender, 98%; cyan, 95%; dark blue, 50%; and pink, 20%). (D) Disease extent in another patient with bilateral, left greater than right, cervical and supraclavicular lymphadenopathy depicted in the axial plan and (E) as a 3-dimensional body reconstruction image with gross tumor contoured in red. (F) Treatment response of the same patient depicted in panels D and E, shown in the axial plane at 7 weeks after photon radiation therapy to the left neck only. A strong partial response to radiation therapy was obtained in this patient.