Tumor response and patterns of failure following intraoperative radiotherapy for unresectable pancreatic cancer--evaluation by computed tomography

Combined CT and serum CA19-9 for stratifying risk for progression in patients with locally advanced pancreatic cancer receiving intraoperative radiotherapy

Background and purpose

The aim of this study was to evaluate the significance of baseline computed tomography (CT) imaging features and carbohydrate antigen 19-9 (CA19-9) in predicting prognosis of locally advanced pancreatic cancer (LAPC) receiving intraoperative radiotherapy (IORT) and to establish a progression risk nomogram that helps to identify the potential beneficiary of IORT.

Methods

A total of 88 LAPC patients with IORT as their initial treatment were enrolled retrospectively. Clinical data and CT imaging features were analyzed. Cox regression analyses were performed to identify the independent risk factors for progression-free survival (PFS) and to establish a nomogram. A risk-score was calculated by the coefficients of the regression model to stratify the risk of progression.

Results

Multivariate analyses revealed that relative enhanced value in portal-venous phase (REV-PVP), peripancreatic fat infiltration, necrosis, and CA19-9 were significantly associated with PFS (all p < 0.05). The nomogram was constructed according to the above variables and showed a good performance in predicting the risk of progression with a concordance index (C-index) of 0.779. Our nomogram stratified patients with LAPC into low- and high-risk groups with distinct differences in progression after IORT (p < 0.001).

Conclusion

The integrated nomogram would help clinicians to identify appropriate patients who might benefit from IORT before treatment and to adapt an individualized treatment strategy.

Pain Palliation Using Hypofractionated Radiotherapy for Unresectable Pancreatic Cancer

BACKGROUND

Pain is a common symptom for patients with pancreatic cancer and is often treated using palliative radiation therapy. Standard palliative dose regimes typically consist of 2000 cGy to 3000 cGy in 5 to 10 fractions (fx). With the recent advancements in radiation dosimetric planning and delivery, the Juravinski Cancer Centre in Hamilton, Ontario, offers a hypofractionated dose of 2500 cGy in 5 fx for the improvement of pain and tumour control in selected pancreatic cancer patients. This project reviews the safety and efficacy of this prescription.

METHODS

A retrospective analysis of 24 patients diagnosed with unresectable pancreatic cancer was conducted. Patient data were collected using in-house medical record systems including MOSAIQ, Meditech, and Centricity. Nonparametric data analysis tests were conducted using Minitab17.

RESULTS

Nineteen of 24 patients (79%) reported a decrease in pain levels following radiation and 13 of 18 (72%) showed good local control of the tumour on a follow-up CT scan. Around 30% of patients reported nausea and vomiting and fatigue. Only 13% reported diarrhea and 8% reported constipation. Twenty-one percent reported pain flares. All patients were able to finish the entire treatment without pauses or delays.

CONCLUSION

A palliative radiotherapy dose regime of 2500 cGy/5 fx demonstrates a potential for the effective control of pain with limited acute toxicities in patients with unresectable pancreatic cancer. This study aims to indicate the need for further prospective research comparing this regime to other standard treatments in order to determine which is most beneficial for the patient.