International Journal of Radiation Oncology*Biology*Physics
Clinical InvestigationStereotactic Body Radiation Therapy for Locally Advanced and Borderline Resectable Pancreatic Cancer Is Effective and Well Tolerated
Introduction
Pancreatic cancer remains a deadly disease with a poor prognosis despite continued advancements in treatment options over the past several decades. Surgical resection with negative margins (R0) remains the only means of providing long-term control and potential cure. Because the signs and symptoms are not usually clinically apparent until the advanced stages, most patients present with unresectable disease leading to dismal 5-year overall survival (OS) rates of <5%. By contrast, resectable patients have markedly improved 5-year OS of 20%. However, even these patients still have a relatively poor long-term prognosis because ultimately most will succumb to distant metastasis (1).
Early data show that patients with unresectable nonmetastatic pancreatic cancer benefit from a combination of radiation therapy (RT) and chemotherapy (2). What remains uncertain is the optimal use of these modalities with respect to sequence, technique, and dosing. One promising strategy for patients with unresectable pancreatic cancer consists of induction chemotherapy followed by chemoradiation or RT alone 3, 4. This approach allows for patients to declare themselves as metastatic and potentially avoid 5 to 6 weeks of chemoradiation (5).
Stereotactic body radiation therapy (SBRT) has been an important recent advance in RT for pancreatic cancer. Pioneered in the LAPC setting, the majority of the SBRT literature has shown SBRT to be well tolerated and effective 6, 7, 8, 9, 10, 11, 12, 13, 14, 15. SBRT also shows promise in the BRPC setting, converting a high percentage of patients to resectability that can result in long-term results similar to those in initially resectable patients (16). This study was performed to review our institutional SBRT outcomes in BRPC and LAPC patients.
Section snippets
Patient details and staging
An institutional review board-approved database was queried to identify nonmetastatic patients with BRPC and LAPC treated with induction chemotherapy followed by SBRT between June 2009 and December 2011. Patients were not included if they underwent SBRT without first undergoing induction chemotherapy. Initial staging included physical examination, standard blood chemistries including CA 19-9, multidetector thin-section pancreatic protocol computed tomography (CT) scan, and endoscopic ultrasound
Patient and treatment characteristics
Table 1 describes the patient and treatment characteristics. A total of 73 patients (57 BRPC, 16 LAPC) were evaluated, with a median age of 64 years (range, 38-87 years). Most patients were clinically node positive (60.3%), with tumors involving the pancreatic head (86.3%). Fourteen clinically node-positive patients (31%) underwent resection. Biliary stent or drain was present in 72% of patients. GTX chemotherapy was the most commonly used induction chemotherapy regimen (65.8%). Sixty-one
Discussion
As has been previously described (16), SBRT can effectively result in tumor regression away from involved vasculature so that surgery can be performed with a high likelihood of negative surgical margins. The importance of margin status cannot be understated, given that it is related to survival outcomes in patients who have not undergone neoadjuvant therapy (17). In this study, the majority of BRPC patients underwent exploratory laparotomy. Remarkably, 3 (9.4%) of the resected patients achieved
References (20)
- et al.
Pancreatic cancer
Lancet
(2004) - et al.
A phase II study of fixed-dose rate gemcitabine plus low-dose cisplatin followed by consolidative chemoradiation for locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2007) - et al.
Phase II study to assess the efficacy of conventionally fractionated radiotherapy followed by a stereotactic radiosurgery boost in patients with locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2005) - et al.
Phase I study of stereotactic radiosurgery in patients with locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2004) - et al.
Single-fraction stereotactic body radiation therapy and sequential gemcitabine for the treatment of locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2011) - et al.
Gemcitabine chemotherapy and single-fraction stereotactic body radiotherapy for locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2008) - et al.
Induction gemcitabine and stereotactic body radiotherapy for locally advanced nonmetastatic pancreas cancer
Int J Radiat Oncol Biol Phys
(2011) - et al.
Stereotactic body radiotherapy and gemcitabine for locally advanced pancreatic cancer
Int J Radiat Oncol Biol Phys
(2010) - et al.
Image-guided stereotactic radiosurgery for locally advanced pancreatic adenocarcinoma results of first 85 patients
J Gastrointest Surg
(2010) - et al.
Phase-II study on stereotactic radiotherapy of locally advanced pancreatic carcinoma
Radiother Oncol
(2005)
Cited by (0)
Conflict of interest: none.