[Role and results of radiotherapy in the treatment of pancreatic adenocarcinoma].

Most pancreatic carcinomas are clinically observed when the tumoral spread is well advanced. Consequently, surgical excision is very often either partial or unfeasible. However, evolutive patterns of pancreatic carcinomas show a long past history of loco-regional spread before the onset of visceral metastasis. Consequently, radiotherapy could be proposed to treat locally advanced pancreatic tumors or residual disease after surgical excision in curative intend. The major challenge dealing with radiotherapeutic management of pancreatic carcinomas is to safely deliver doses as high as 60-70 Gy into the upper half of the abdominal cavity. Several technical conditions must be fulfilled before this can take place: high energy and multiple convergent photon beams, precise surgical and/or radiological description of tumoral extent, careful sparing of critical tissues such as spinal cord and kidneys. Usually, radiotherapeutic planning is administered in 2 successive sessions: 40-45 Gy are first administered to the tumor and main nodal drainage over 4-6 weeks, then a 15-25 Gy boost dose is given to the primary tumor bed only. However, postoperative irradiation after complete removal of a gross tumor gives a 10% survival rate only at 2 years. Improvement of these results, are eventually expected from intra-operative irradiation techniques or radiochemotherapy combined treatments.