What are the indications for radiotherapy in pancreatic cancer?

From the Guidelines

Radiotherapy is indicated for pancreatic cancer in 2025 as neoadjuvant therapy for borderline resectable disease, as adjuvant treatment following surgical resection, and as definitive treatment for locally advanced unresectable disease, often combined with chemotherapy. The indications for radiotherapy in pancreatic cancer are based on the clinical scenario and the goal of treatment. For borderline resectable disease, neoadjuvant radiotherapy can be used to downstage tumors before surgery, with the goal of achieving a margin-negative resection. As adjuvant treatment, radiotherapy can be used to reduce local recurrence after surgical resection. For locally advanced unresectable disease, radiotherapy can be used as definitive treatment, often in combination with chemotherapy, to achieve local tumor control and improve survival outcomes.

Some key points to consider when using radiotherapy for pancreatic cancer include:

• The use of modern techniques like intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT) to improve treatment precision and reduce toxicity to surrounding organs
• The sequencing of radiotherapy with systemic chemotherapy regimens like FOLFIRINOX or gemcitabine/nab-paclitaxel
• The importance of restaging patients with abdominal and chest imaging and diagnostic laparoscopy before committing them to laparotomy after neoadjuvant therapy
• The recommendation for neoadjuvant therapy as an alternative to up-front resection after disease is clinically staged as borderline resectable, as stated in the NCCN guidelines 1
• The use of stereotactic body radiation therapy (SBRT) delivering 30-40 Gy in 5 fractions for borderline resectable disease, or conventional fractionation of 45-54 Gy over 5-6 weeks for adjuvant treatment, as mentioned in the guidelines 1

It's worth noting that the optimal neoadjuvant regimen has not been established, and the use of preoperative chemoradiation to convert selected patients with unresectable disease to a resectable status is still under investigation, as mentioned in the study by Tempero et al. 1. However, the available evidence suggests that radiotherapy can be an effective treatment option for pancreatic cancer, and its use should be considered in the context of a multidisciplinary treatment approach.

From the Research

Indications of Radiotherapy in Pancreas Cancer

• The use of radiation therapy for patients with pancreatic cancer is subject to discussion 2
• Chemoradiation may improve the survival of patients with incompletely resected tumours (R1) 2
• Neoadjuvant chemoradiation is a promising treatment especially for patients with borderline resectable tumours 2
• For patients with locally advanced tumours, there is no standard treatment, but an induction chemotherapy followed by chemoradiation for non-progressive patients reduces the rate of local relapse 2

Radiotherapy Techniques

• Intensity modulated radiation therapy allows a reduction of doses to the organs at risk 2
• Stereotactic body radiation therapy is also being studied, as a neoadjuvant or exclusive treatment 2
• Magnetic resonance guided radiation therapy may safely permit radiation and chemotherapy dose escalation 3

Combination with Chemotherapy

• Gemcitabine plus nab-paclitaxel with ablative magnetic resonance guided radiation therapy dosing is safe in patients with borderline resectable or locally advanced pancreatic ductal adenocarcinoma (BR/LA-PDAC) 3
• FOLFIRINOX improves overall survival (OS) and delays deterioration in quality of life, but increases grade 3/4 adverse events 4
• Gemcitabine plus taxane results in a large improvement in OS and likely increases grade 3/4 adverse events and improves quality of life 4

Comparison of Treatment Outcomes

• Patients who received chemoradiation with gemcitabine did not differ in outcomes compared with chemoradiation with 5-fluorouracil 5
• Patients with low-grade resected pancreatic cancer may have better outcomes with 5-fluorouracil-based chemotherapy without radiation when compared with 5-fluorouracil with radiation 5
• Gemcitabine chemotherapy and 5-fluorouracil-based concurrent chemoradiotherapy showed similar survival advantages in locally advanced unresectable pancreatic cancer 6