Background/aims: Chemoradiation therapy is widely indicated to patients with locally advanced pancreatic carcinoma, though the capability of radiotherapy alone is not assessed enough. The purpose of this study is to clarify the efficacy and safety of a more intensive radiotherapy for those patients.
Methodology: Fifteen patients were enrolled in a feasible phase II study of treatment with intraoperative radiation therapy (25 Gy), followed by conformal external-beam radiation therapy (40 Gy in 20 fractions, 5 times/week). The antitumor effect was evaluated on the early phase of dynamic computed tomography image.
Results: The full irradiation dose was feasible in 12 of 15 patients. The overall response rate was 40% (1 complete and 5 partial responses). Grade 3 toxicity was observed in 2 patients (13%) with nausea/vomiting or anorexia. One patient developed gastric ulcer and died of gastrointestinal bleeding 12 months after intraoperative radiation therapy. The median survival time was 11.1 months, and the 2-year survival rates were 13%. Survival for more than 2 years was observed in 2 of the 6 responders.
Conclusions: The above radiotherapy is considered to be active for the locally advanced pancreatic cancer with acceptable toxicity, when the gastrointestinal tract is excluded from the radiation field. This should be further assessed in late phase II studies involving a large number of patients.