Effectiveness of Carbon Ion Radiation in Locally Advanced Pancreatic Cancer

Jakob Liermann; Patrick Naumann; Fabian Weykamp; Philipp Hoegen; Juergen Debus; Klaus Herfarth

doi:10.3389/fonc.2021.708884

Effectiveness of Carbon Ion Radiation in Locally Advanced Pancreatic Cancer

Front Oncol. 2021 Jul 14:11:708884. doi: 10.3389/fonc.2021.708884. eCollection 2021.

Authors

Jakob Liermann^{1

2

3

4

5}, Patrick Naumann^{1

2

3}, Fabian Weykamp^{1

2

3}, Philipp Hoegen^{1

2

3

4}, Juergen Debus^{1

2

3

4

5

6}, Klaus Herfarth^{1

2

3

4

5

6}

Affiliations

¹ Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.
² Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany.
³ National Center for Tumor Diseases (NCT), Heidelberg, Germany.
⁴ Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
⁵ Heidelberg Ion Beam Therapy Center, Heidelberg, Germany.
⁶ German Cancer Consortium (DKTK), partner site Heidelberg, German Cancer Research Center (DKFZ), Heidelberg, Germany.

Abstract

Purpose: Effective treatment strategies for unresectable locally advanced pancreatic cancer (LAPC) patients are eagerly warranted. Recently, convincing oncological outcomes were demonstrated by carbon ion radiotherapy. Nevertheless, there is a lack of evidence for this modern radiation technique due to the limited number of carbon ion facilities worldwide. Here, we analyze feasibility and efficacy of carbon ion radiotherapy in the management of LAPC at Heidelberg Ion Beam Therapy Center (HIT).

Methods: Between 2015 and 2020, 21 LAPC patients were irradiated with carbon ions with a total dose of 48 Gy (RBE) in single doses of 4 Gy (RBE). Three patients (14%) were treated with concomitant chemotherapy with gemcitabine 300 mg/m² body surface weekly. Toxicity rates were extracted from the charts. Overall survival, progression free survival, local control, and locoregional control were evaluated using Kaplan-Meier estimates.

Results: One patient developed ascites CTCAE grade III during radiotherapy, which was related to a later histologically confirmed metachronous peritoneal carcinomatosis. No further higher-graded toxicity could be observed. The most common symptoms were nausea and abdominal pain. After a median estimated follow-up time of 19.1 months, the median progression free survival was 3.7 months, and the median overall survival was 11.9 months. The estimated 1-year local control and locoregional control rates were 89 and 84%, respectively.

Conclusion: Carbon ion radiotherapy of LAPC patients is safely feasible. Local tumor control rates were high. Nevertheless, compared to historical data, an overall survival improvement could not be observed. This could be explained by the poor prognosis of the selected underlying patients that mostly did not respond to prior chemotherapy as well as the early and frequent emergence of distant metastases that demonstrate the necessity of additional chemotherapy in further studies.

Keywords: carbon ion radiotherapy; heavy ion; irradiation; locally advanced pancreatic cancer; pancreatic cancer; particle therapy.