fbpx
loading
pexels terje sollie
July 31, 2024
 

Role of Radiotherapy in Borderline and Locally Advanced Pancreatic Cancer

 

Recommendations for RT for patients with pancreatic cancer are typically made based on a few clinical scenarios:

Borderline resectable  > to sterilise surgical margins

Locally advanced > ablative radiotherapy for longer term control

Palliative > coeliac plexus SBRT for pain relief, or local RT for symptoms

The goal of delivering RT is to sterilize vessel margins, enhance the likelihood of a margin-negative resection, and/or provide adequate local control to prevent or delay progression or prevent local disease recurrence while minimizing the risk of RT exposure to surrounding organs at risk (OARs). Radiation can also be used to palliate pain and bleeding or relieve obstructive symptoms in patients who have progressed or recurred locally.

 

Purpose:

  • Shrink Tumors: Radiotherapy is used to shrink tumors that are close to major blood vessels, making them more operable.
  • Control Disease Progression: Helps to control the growth of the cancer and potentially slow its spread.
  • Alleviate Symptoms: Can be used to relieve symptoms such as pain by reducing the size of the tumor.

Types of Radiotherapy:

  • External Beam Radiotherapy (EBRT): The most common type, where high-energy rays are directed at the tumor from outside the body.
  • Stereotactic Body Radiotherapy (SBRT): Delivers highly precise radiation doses to the tumor, minimizing damage to surrounding tissues.

Treatment fractionations vary according to indication and type of radiotherapy.

For neoadjuvant chemoradiation, RT dose generally consists of 45–54 Gy in 1.8–2.0 Gy fractions.

For unresectable ablative radiotherapy, there are limited data to support a specific RT dosing for SBRT; SBRT doses of 3 fractions (total dose 30–45 Gy) or 5 fractions (total dose 25–50 Gy) have been reported.

More protracted courses delivering high doses through a hypofractionated approach (67.5 Gy in 15 fractions or 75 Gy in 25 fractions) are also acceptable. 

Process of Radiotherapy in Pancreatic Cancer

  1. Diagnosis and Staging:

    • Imaging: CT scans, MRI, and PET scans to determine the size and location of the tumor and its relation to nearby structures.
    • Biopsy: To confirm the diagnosis of pancreatic cancer.

  2. Treatment Planning:

    • Simulation: A planning session where the patient is positioned and immobilized to ensure consistent treatment delivery.
    • Mapping: Detailed imaging (often a CT scan) is used to map the exact location, shape, and size of the tumor.
    • Dosimetry: Radiation oncologists calculate the optimal radiation dose to maximize tumor control while minimizing damage to normal tissues.

Optimal elective irradiation target remains undefined, but broad coverage of mesenteric vasculature +/- nodal regions should be considered when feasible

 

  1. Treatment Delivery:

    • Sessions: Radiotherapy is typically delivered in multiple sessions over several weeks.
    • Positioning: The patient is carefully positioned for each session to ensure accurate targeting.
    • Radiation Delivery: High-energy radiation beams are directed at the tumor site. Each session lasts a few minutes, but the setup time can be longer.

  2. Follow-Up and Monitoring:

    • Regular Imaging: To assess the tumor’s response to treatment.
    • Symptom Management: Ongoing evaluation and management of any side effects or complications from the treatment.
    • Adjustments: Modifications to the treatment plan may be made based on the tumor’s response and patient’s tolerance.

Side Effects of Radiotherapy in Pancreatic Cancer

 

Common Side Effects:

  • Fatigue: General tiredness that may increase over the course of treatment.
  • Nausea and Vomiting: Can occur due to the proximity of the treatment area to the stomach.
  • Diarrhea: Radiation can affect the intestines, leading to gastrointestinal side effects.
  • Skin Changes: Redness, irritation, and sensitivity in the treated area.

Less Common Side Effects:

  • Abdominal Pain: Discomfort or pain in the abdomen.
  • Loss of Appetite: Reduced desire to eat, potentially leading to weight loss.

Rare but Serious Side Effects:

  • Radiation-induced Damage: To nearby organs such as the stomach, intestines, liver, or kidneys.

Radiotherapy plays a crucial role in the multidisciplinary approach to treating borderline and locally advanced pancreatic cancer, aiming to make tumors operable and to manage symptoms, thus improving patient outcomes and quality of life.