Postirradiation changes on the lymphatics studied by lymphography.

Repeat lymphography was done in 33 patients following radiotherapy between 8--73 months. Absorbed dose delivered by 60Co-teletherapy ranged between 30--45 Gy-s in subdiaphragmatic and 30,6--56 Gy-s in mediastinal region. The main sequel of radiation was decrease in nodal size (66,6%), lumen narrowing of lymphatic vessels (51,5%); number of lymph nodes and lymph vessels diminished rarely (6%). Blocking of lymph circulation never developed. Dilatation of thoracic duct with accelerated contrast flow rate was thought to be arteficial due to decreased pooling capacity of decreased nodal size. Radiation induced changes develop within 12 months and do not progress further on. It is concluded that changes are mainly affected by the level of absorbed dose.