Pancreatic cancer (PC) is a disease where malignant cells form in the tissues of the pancreas, an organ situated behind the stomach that produces digestive enzymes and hormones like insulin. Metastatic pancreatic cancer describes the advanced stage (Stage IV) where cancer cells have broken away from the original tumor and traveled to distant parts of the body. This spread makes the disease challenging to treat, establishing it as a serious and advanced condition, as the process is no longer confined to the pancreas or its immediate surrounding tissue.
Defining Advanced Pancreatic Cancer
Metastasis is a complex biological process that allows cancer cells to move through the body, primarily by invading the lymphatic system or entering the bloodstream. Once in these circulatory pathways, pancreatic cancer cells can travel far and settle in other organs to form new tumors. Even when established elsewhere, such as in the liver, the new tumor is still identified and treated as metastatic pancreatic cancer, not as liver cancer.
The disease is often discovered at this advanced stage because the pancreas is deeply located, and early-stage tumors typically do not cause noticeable symptoms. The most common site for spread is the liver, due to the direct blood flow connection. Other frequent sites include the lungs, the peritoneum (the lining of the abdominal cavity), and distant lymph nodes. When the cancer has spread to distant sites, it is considered unresectable, shifting the focus of treatment toward systemic control.
Recognizing Symptoms of Metastasis
When pancreatic cancer spreads to distant organs, it causes symptoms related to the affected site. Spread to the liver can cause jaundice, characterized by the yellowing of the skin and eyes resulting from a buildup of bilirubin. Liver involvement may also lead to abdominal swelling and discomfort.
Cancer cells in the peritoneum may cause ascites, a buildup of fluid in the abdomen that contributes to fullness and bloating. When the cancer spreads to the lungs, a person might experience a persistent cough, chest pain, or difficulty breathing. Systemic symptoms also become pronounced, including severe, unexplained weight loss, profound fatigue, and worsening abdominal or back pain.
Systemic Treatment Options
The primary goal of treating metastatic pancreatic cancer is controlling the disease, slowing its progression, and maintaining quality of life. Systemic treatments, which circulate throughout the body, are the main approach because they target cancer cells wherever they have spread. Chemotherapy is the foundation of this treatment, and two combination regimens are widely used as first-line therapy for patients in good general health.
FOLFIRINOX Regimen
One regimen is FOLFIRINOX, which combines four drugs:
- Folinic acid
- 5-fluorouracil
- Irinotecan
- Oxaliplatin
This combination has demonstrated superior outcomes in clinical trials compared to older treatments, but it is associated with higher rates of side effects, such as severe fatigue, diarrhea, and a drop in blood counts. FOLFIRINOX is typically reserved for patients with a high performance status, meaning they are active and fit enough to tolerate the aggressive nature of the drugs.
Gemcitabine/Nab-Paclitaxel
The second common first-line regimen is a combination of gemcitabine and nab-paclitaxel, often referred to as Gemcitabine/Abraxane. This therapy is effective at controlling the disease and may be an option for patients who are not strong enough for FOLFIRINOX, as it tends to have a more manageable toxicity profile. The choice between these two regimens depends heavily on a patient’s overall health and the specific side effects they are able to manage.
Targeted and Immunotherapy Approaches
Targeted therapy and immunotherapy play a limited but growing role in the management of metastatic pancreatic cancer. Targeted drugs focus on specific genetic changes in the cancer cells, such as a BRCA gene mutation, and are only applicable to a small subset of patients whose tumors possess these alterations. Immunotherapy, which harnesses the body’s immune system to attack cancer cells, is currently effective only for the rare patient whose tumor shows high levels of specific genetic markers, such as microsatellite instability. Clinical trials are an important avenue for patients with advanced disease, offering access to novel treatments still under investigation.
Managing Supportive Care Needs
Supportive care, often delivered through a palliative care approach, works alongside active cancer treatment to manage symptoms and improve daily life from the time of diagnosis. Unlike active treatment, supportive care focuses on the needs of the patient, not just the disease. Pain management is a cornerstone of this care, since tumors can invade nearby nerves, causing significant discomfort that may require strong opioid medications or specialized nerve blocks.
Nutritional support is essential, as pancreatic cancer can impair the organ’s ability to produce digestive enzymes, leading to weight loss and malabsorption. Pancreatic enzyme replacement therapy (PERT) is commonly prescribed to help the body break down food and absorb fat-soluble vitamins. Dietitians assist patients by recommending small, frequent meals and ensuring adequate caloric intake to combat muscle wasting.
Managing chemotherapy side effects, such as nausea and fatigue, utilizes anti-nausea medications and energy conservation strategies. Psychological and emotional support, including counseling and social work services, is provided to help the patient and their family cope with the challenges of an advanced cancer diagnosis. This comprehensive approach ensures that symptom control and quality of life remain paramount.