Margin status after pre-operative radiation for borderline resectable pancreatic cancer

Committee/Faculty

Presenting Author(s)

JJ

James R. Janopaul-Naylor, n/a

M.D.
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.

Co-Author(s)

RB

Riley Brackin, n/a

n/a
Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
YL

Yingzi Liu

PhD
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
JL

Jolinta Lin

M.D.
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
MM

Mark McDonald, n/a

M.D.
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
XY

Xiaofeng Yang, n/a

PhD
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
BE

Bassel El-Rayes

MD
Department of Hematology and Medical Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
WS

Walid L. Shaib

M.D.
Department of Hematology and Medical Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
OA

Olatunji B. Alese

M.D.
Department of Hematology and Medical Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
MA

Mehmet Akce

M.D.
Department of Hematology and Medical Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
DK

David A. Kooby

M.D.
Department of Surgery, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
SM

Shishir K. Maithel

M.D.
Department of Surgery, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
JS

Juan M. Sarmiento

M.D.
Department of Surgery, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.
PP

Pretesh R. Patel

M.D.
Department of Radiation Oncology, Emory University School of Medicine
Atlanta, Georgia, United States

Disclosure: Disclosure information not submitted.

Purpose: The role of radiation in the management of pancreatic cancer remains controversial. Initial report from the Alliance A021501 trial indicates high dose SBRT or hypofractionated radiotherapy (RT) may be associated with lower rates of resection, higher rates of margin positivity, and worse outcomes in patients with borderline resectable pancreatic cancer treated with neoadjuvant FOLFIRINOX. This study aimed to assess outcomes after neoadjuvant conventional RT or SBRT for borderline resectable pancreatic cancer.

Methodology: Multi-center retrospective review of 28 consecutive patients with borderline resectable pancreatic cancer treated with radiation from 2014 to 2019. Logistic regression used to assess associations of chemotherapy and radiation with overall survival and margin status (negative, <1 mm, or positive) in SAS.

Results: Median age was 62 (range 48-83) and Karnofsky Performance Status 80% (range 60%-100%) with median overall survival 32 months (range 9-75 months). All patients received neoadjuvant chemotherapy; FOLFIRINOX used for 39% (n=11) with 36% (n=4) completing 8 cycles. While 68% (n=19) received conventionally fractionated radiation (1.8 Gy per fraction to 45-50.4 Gy), 32% (n=9) received SBRT (n=7; 6.6-8 Gy per fraction to 33-40 Gy) or dose-escalated fractionated therapy (n=2; 2.4 Gy per fraction to 60 Gy). Survival was significantly associated with performance status (p=0.04) and receipt of SBRT or dose-escalated radiotherapy (p=0.01). On pathology, 43% (n=12) had widely negative margins, 29% (n=8) had close margins, and 29% (n=8) had positive margins (pancreatic neck [n=5], retroperitoneal [n=2], or vascular interface [n=3]) with 7% (n=2) having a pathologic complete response and 7% (n=2) having a near complete response ( <10% viable tumor remaining). Of the 9 patients who received dose-escalated radiation or SBRT, 67% (n=6) had widely negative margins, 22% (n=2) had close margins, and 11% (n=1) had positive margins at pancreatic neck and portal vein. In contrast, of the 19 patients who had conventionally fractionated radiation, 37% (n=7) had widely negative margins, 32% (n=6) had close margins, and 32% (n=6) had positive margins. Resection with positive margins was not associated with receipt of SBRT or dose-escalated radiation (p=0.07) or number of cycles of chemotherapy (p=0.17) but was associated with FOLFIRINOX (versus other) chemotherapy (p < 0.01).

Conclusions: For patients with borderline resectable pancreatic cancer treated with neoadjuvant chemotherapy, SBRT or high dose fractionated RT was not associated with a higher rate of margin positive resection.

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