Daly N J, Izar F, Bugat R, Bachaud J M, Delannes M
Centre Claudius-Regaud, Toulouse, France.
Bull Cancer. 1990;77(3):261-6.
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.
大多数胰腺癌在肿瘤扩散进展到相当程度时才被临床观察到。因此，手术切除往往要么是局部的，要么不可行。然而，胰腺癌的演变模式显示，在内脏转移发生之前，局部区域扩散已有很长的病史。因此，可以考虑用放疗来治疗局部晚期胰腺癌或手术切除后有治愈意图的残留病灶。胰腺癌放射治疗管理面临的主要挑战是如何安全地将60 - 70 Gy的剂量输送到腹腔上半部分。在这之前必须满足几个技术条件：高能和多束汇聚光子束、对肿瘤范围进行精确的手术和/或放射学描述、小心保护脊髓和肾脏等关键组织。通常，放射治疗计划分两个连续疗程进行：首先在4 - 6周内对肿瘤和主要淋巴结引流区给予40 - 45 Gy的剂量，然后仅对原发肿瘤床给予15 - 25 Gy的追加剂量。然而，在完全切除肉眼可见肿瘤后进行术后放疗，2年生存率仅为10%。最终期望通过术中放疗技术或放化疗联合治疗来改善这些结果。
