[en] Twenty-three patients with Hodgkin's disease and malignant testicular tumours had repeat bipedal lymphography 13-73 months following radiotherapy. Cobalt-60 teletherapy was administered either with prophylactic or therapeutic intent by two opposed fields, which encompassed the whole infra-diaphragmatic (inguinofemoral, pelvic and para-aortic) lymph region. Most patients received also radiotherapy to the whole mediastinal lymph region. The lowest tumour dose was of 3000 rads (30 Gy), the highest of 4500 rads (45 Gy) to the infra-diaphragmatic region, with a total weekly dose of 900-1000 rads (9-10 Gy) given in five fractions. Number, calibre and valves of lymphatic vessels, transport capacity, collateral pathways; the filling and width of the thoracic duct, the number, size, shape and storage character of lymph nodes were compared on the first and repeat lymphography films. The number of lymphatic vessels was hardly influenced by radiotherapy, and calibre narrowing was seen in more than half of the patients. The size of lymph nodes was drastically decreased, especially in those who received a tumour dose over 3000 rads (30 Gy). Since new collateral pathways could not be found, it seems obvious that radiotherapy between these dose ranges does not reduce the transport capacity of lymphatic vessels. (author)