Carbon ion radiotherapy as definitive treatment in non-metastasized pancreatic cancer: study protocol of the prospective phase II PACK-study.

BACKGROUND

Radiotherapy is known to improve local tumor control in locally advanced pancreatic cancer (LAPC), although there is a lack of convincing data on a potential overall survival benefit of chemoradiotherapy over chemotherapy alone. To improve efficacy of radiotherapy, new approaches need to be evolved. Carbon ion radiotherapy is supposed to be more effective than photon radiotherapy due to a higher relative biological effectiveness (RBE) and due to a steep dose-gradient making dose delivery highly conformal.

METHODS

The present Phase II PACK-study investigates carbon ion radiotherapy as definitive treatment in LAPC as well as in locally recurrent pancreatic cancer. A total irradiation dose of 48 Gy (RBE) will be delivered in twelve fractions. Concurrent chemotherapy is accepted, if indicated. The primary endpoint is the overall survival rate after 12 months. Secondary endpoints are progression free survival, safety, quality of life and impact on tumor markers CA 19-9 and CEA. A total of twenty-five patients are planned for recruitment over 2 years.

DISCUSSION

Recently, Japanese researches could show promising results in a Phase I/II-study evaluating chemoradiotherapy of carbon ion radiotherapy and gemcitabine in LAPC. The present prospective PACK-study investigates the efficacy of carbon ion radiotherapy in pancreatic cancer at Heidelberg Ion Beam Therapy Center (HIT) in Germany.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov: NCT04194268 (Retrospectively registered on December, 11th 2019).