Impact of neoadjuvant intensity-modulated radiation therapy on borderline resectable pancreatic cancer with arterial abutment; a prospective, open-label, phase II study in a single institution

BMC Cancer. 2022 Jan 29;22(1):119. doi: 10.1186/s12885-022-09244-6.

Abstract

Background: Borderline resectable pancreatic cancer (BRPC) is a category of pancreatic cancer that is anatomically widely spread, and curative resection is uncommon with upfront surgery. Intensity-modulated radiation therapy (IMRT) is a form of radiation therapy that delivers precise radiation to a tumor while minimizing the dose to surrounding normal tissues. Here, we conducted a phase 2 study to estimate the curability and efficacy of neoadjuvant chemoradiotherapy using IMRT (NACIMRT) for patients with BRPC with arterial abutment (BRPC-A).

Methods: A total of 49 BRPC-A patients were enrolled in this study and were treated at our hospital according to the study protocol between June 2013 and March 2021. The primary endpoint was microscopically margin-negative resection (R0) rates and we subsequently analyzed safety, histological effect of the treatment as well as survivals among patients with NACIMRT.

Results: Twenty-nine patients (59.2%) received pancreatectomy after NACIMRT. The R0 rate in resection patients was 93.1% and that in the whole cohort was 55.1%. No mortality was encountered. Local therapeutic effects as assessed by Evans classification showed good therapeutic effect (Grade 1, 3.4%; Grade 2a, 31.0%; Grade 2b, 48.3%; Grade 3, 3.4%; Grade 4, 3.4%). Median disease-free survival was 15.5 months. Median overall survival in the whole cohort was 35.1 months. The only independent prognostic pre-NACIMRT factor identified was serum carbohydrate antigen 19-9 (CA19-9) > 400 U/ml before NACIMRT.

Conclusions: NACIMRT showed preferable outcome without significant operative morbidity for BRPC-A patients. NACIMRT contributes to good local tumor control, but a high initial serum CA19-9 implies poor prognosis even after neoadjuvant treatment.

Trial registration: UMIN-CTR Clinical Trial: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000011776 Registration number: UMIN000010113. Date of first registration: 01/03/2013.

Keywords: Intensity-Modulated Radiotherapy; Neoadjuvant therapy; Pancreatic cancer; Surgery.

Publication types

  • Clinical Trial, Phase II

MeSH terms

  • Aged
  • Antigens, Tumor-Associated, Carbohydrate / blood
  • Arteries
  • Female
  • Humans
  • Male
  • Margins of Excision
  • Middle Aged
  • Neoadjuvant Therapy*
  • Pancreatectomy
  • Pancreatic Neoplasms / mortality*
  • Pancreatic Neoplasms / therapy*
  • Prospective Studies
  • Radiotherapy, Intensity-Modulated*
  • Treatment Outcome

Substances

  • Antigens, Tumor-Associated, Carbohydrate
  • carbohydrate antigen 199, human