Dataset Information

Evaluation of a Novel Absorbable Radiopaque Hydrogel in Patients Undergoing Image Guided Radiation Therapy for Borderline Resectable and Locally Advanced Pancreatic Adenocarcinoma.

ABSTRACT:

Purpose

We assessed the feasibility and safety of placing a radiopaque hydrogel in the pancreaticoduodenal groove via endoscopic ultrasound guidance in patients with borderline resectable/locally advanced pancreatic cancer (BR/LAPC).

Methods and materials

Hydrogel injections were done at time of fiducial placement to form blebs in the pancreaticoduodenal groove. Patients subsequently underwent simulation computed tomography (sim-CT) followed by hypofractionated stereotactic body radiotherapy (SBRT; 33 Gy in 5 fractions). Four to 8 weeks after SBRT, patients underwent CT re-evaluation for surgical candidacy and assessment of hydrogel location and size. Hydrogel placement was considered successful if identified in the pancreaticoduodenal groove on sim-CT scan. Stability was evaluated using equivalence testing analyses, with a null hypothesis of the presence of a ≥20% mean percentage change in volume and ≥2 mm change in the median and mean interbleb surface distance with a P value <.05 required to reject the null hypothesis and conclude equivalence. For patients undergoing pancreaticoduodenectomy, hydrogel sites were histologically examined for location and local inflammatory reactions.

Results

Hydrogel placement was successful in 6 of the 6 evaluable patients. The average changes in median and mean interbleb distances were -0.43 mm and -0.35 mm, respectively, with P < .05. The average change in volume from sim-CT to post-SBRT CT was -1.0%, with P < .05. One patient experienced grade 3 nausea after fiducial/hydrogel placement, with no other adverse events to date.

Conclusions

These data demonstrate feasibility and safety of injecting a hydrogel marker in the pancreaticoduodenal groove in patients with BR/LAPC and set the stage for a follow-up clinical trial to place hydrogel as a spacer between the pancreatic tumor and dose-limiting, radiosensitive duodenum.

SUBMITTER: Rao AD

PROVIDER: S-EPMC7483342 | biostudies-literature | 2020 Nov - Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evaluation of a Novel Absorbable Radiopaque Hydrogel in Patients Undergoing Image Guided Radiation Therapy for Borderline Resectable and Locally Advanced Pancreatic Adenocarcinoma.

Rao Avani Dholakia AD Shin Eun Ji EJ Meyer Jeffrey J Thompson Elizabeth L EL Fu Wei W Hu Chen C Fishman Elliot K EK Weiss Matthew M Wolfgang Christopher C Burkhart Richard R He Jin J Kerdsirichairat Tossapol T Herman Joseph M JM Ding Kai K Narang Amol A

Practical radiation oncology 20200307 6

<h4>Purpose</h4>We assessed the feasibility and safety of placing a radiopaque hydrogel in the pancreaticoduodenal groove via endoscopic ultrasound guidance in patients with borderline resectable/locally advanced pancreatic cancer (BR/LAPC).<h4>Methods and materials</h4>Hydrogel injections were done at time of fiducial placement to form blebs in the pancreaticoduodenal groove. Patients subsequently underwent simulation computed tomography (sim-CT) followed by hypofractionated stereotactic body r ...[more]

PMID: 32151732

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Project description:Pancreatic ductal adenocarcinoma (PDAC) is currently ranked fourth place of cancer related mortality. Only a minority of 10-20% of patients with PDAC have a primarily resectable disease, while 50-60% of the patients are diagnosed with irresectable disease. A certain group of patients is defined as "borderline resectable", which is mainly relied to contact of the tumor to major abdominal vessels. For preoperative evaluation of resectability CT and MRI is commonly used. Although CT-scanning, which is the standard preoperative imaging modality, has striking limitations concerning evaluation of lymph node status as well as vessel involvement and approximately 20% of the patients are staged incorrectly. A central part of modern therapy of locally advanced or not primarily resectable PDAC is neoadjuvant therapy. Especially neoadjuvant chemotherapy according to the FOLFIRINOX protocol resulted in high resection rates of initially not resectable patients. Furthermore, treatment with FOLFIRINOX was shown to be an independent predictor of improved prognosis and resection after neoadjuvant treatment with FOLFIRINOX was associated with improved survival. Neoadjuvant treatment was able to increases the rates of R0 resection, which depicts an independent prognostic factor and FOLFIRINOX outmatched other treatment regimes (e.g., gemcitabine-based radio-chemotherapy) concerning achievement of a R0 resection. While most evidence of neoadjuvant treatment of PDAC is conferred by retrospective analysis, there is growing data from randomized controlled trials, confirming the beneficial effects of neoadjuvant therapy on the prognosis of PDAC. Thus, patients with borderline resectable and locally advanced PDAC should be evaluated for neoadjuvant treatment. If there is no progression of the disease during neoadjuvant treatment exploration with the goal of R0 resection should be performed. If possible, patients should be included in well-designed randomized controlled trials at specialized pancreatic centers.

Project description:ImportanceChemotherapy is the recommended induction strategy in borderline resectable and locally advanced pancreatic ductal adenocarcinoma. However, the associated results on an intention-to-treat basis are poorly understood.ObjectiveTo investigate pragmatically the treatment compliance, conversion to surgery, and survival outcomes of patients with borderline resectable and locally advanced pancreatic ductal adenocarcinoma undergoing primary chemotherapy.Design, setting, and participantsThis prospective study took place in a national referral center for pancreatic diseases in Italy. Consecutive patients with borderline resectable and locally advanced pancreatic ductal adenocarcinoma were enrolled at the time of diagnosis (January 2013 through December 2015) and followed up to June 2018.ExposuresThe chemotherapy regimen, assigned based on multidisciplinary evaluation, was delivered either at a hub center or at spoke centers. By convention, primary chemotherapy was considered completed after 6 months. After restaging, surgical candidates were selected based on radiologic and biochemical response. All surgeries were carried out at the hub center.Main outcomes and measuresRates of receipt and completion of chemotherapy, rates of conversion to surgery, and disease-specific survival.ResultsOf 680 patients, 267 (39.3%) had borderline resectable and 413 (60.7%) had locally advanced pancreatic ductal adenocarcinoma. Overall, 66 patients (9.7%) were lost to follow-up. The rate of chemotherapy receipt was 92.9% (n = 570). The chemotherapeutic regimens most commonly used included FOLFIRINOX (fluorouracil, leucovorin, oxaliplatin, and irinotecan) (260 [45.6%]) and gemcitabine plus nanoparticle albumin-bound-paclitaxel (123 [21.6%]). Nineteen patients (3.3%) receiving chemotherapy died within 6 months, mainly for disease progression. The treatment completion rate was 71.6% (408 of 570). The overall rate of resection was 15.1% (93 of 614) (borderline resectable, 60 of 249 [24.1%]; locally advanced, 33 of 365 [9%]; resection:exploration ratio, 63.3%). Independent predictors of resection were age, borderline resectable disease, chemotherapy completion, radiologic response, and biochemical response. The median survival for the whole cohort was 12.8 (95% CI, 11.7-13.9) months. Factors independently associated with survival were completion of chemotherapy, receipt of complementary radiation therapy, and resection. In patients who underwent resection, the median survival was 35.4 (95% CI, 27.0-43.7) months for initially borderline resectable and 41.8 (95% CI, 27.5-56.1) months for initially locally advanced disease. No pretreatment and posttreatment factors were associated with survival after pancreatectomy.Conclusions and relevanceThis pragmatic observational cohort study with an intention-to-treat design provides real-world evidence of outcomes associated with the most current primary chemotherapy regimens used for borderline resectable and locally advanced pancreatic ductal adenocarcinoma.

Dataset Information

Evaluation of a Novel Absorbable Radiopaque Hydrogel in Patients Undergoing Image Guided Radiation Therapy for Borderline Resectable and Locally Advanced Pancreatic Adenocarcinoma.

Purpose

Methods and materials

Results

Conclusions

Publications

Evaluation of a Novel Absorbable Radiopaque Hydrogel in Patients Undergoing Image Guided Radiation Therapy for Borderline Resectable and Locally Advanced Pancreatic Adenocarcinoma.

Similar Datasets

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