New Consensus Defines Oligometastatic Pancreatic Cancer for Targeted Treatment
Historically, local treatments such as surgery have typically not been an option for metastatic pancreatic cancer once the tumor has spread. However, recent studies have indicated that a small group of patients with a limited number of metastases, known as oligometastases, could potentially benefit from a combination of drug therapy and local treatment. A uniform definition for this critical condition had not previously existed.
An international group of experts, led by MedUni Vienna, has now developed a consensus definition. The findings from the "OligoPanc" project have been published in The Lancet Oncology, aiming to facilitate the improvement of specific treatment strategies.
Developing the Consensus
Fifty-five experts from 20 countries and five medical disciplines participated in a structured consensus process. This extensive project was coordinated by Carl-Stephan Leonhardt, Oliver Strobel, and Gerald W. Prager from MedUni Vienna. Through a multi-stage, anonymous voting process (Delphi process) and comprehensive case studies, the group successfully established key criteria for defining oligometastasis in pancreatic cancer.
The Oligometastasis Consensus Defined
The consensus specifies that a maximum of three metastases in a single organ are considered oligometastatic. The liver and lungs were identified as the affected organs.
A crucial distinction is made between:
- Synchronous oligometastasis: Present at the time of initial diagnosis.
- Metachronous oligometastasis: Develops during the course of the disease.
For metachronous forms, a longer interval between initial diagnosis and the appearance of metastases is considered a favorable prognostic sign.
Diagnosis and Treatment Pathways
Diagnostic Standards
For diagnosing oligometastasis in pancreatic cancer, the expert group reached a consensus on the necessary imaging techniques. These include contrast-enhanced computed tomography of the chest and abdomen, and magnetic resonance imaging of the liver. Crucially, diagnosis should always be conducted by a multidisciplinary tumor board, involving specialists from various fields such as surgery, oncology, radiology, and radiotherapy.
Treatment Recommendations
Based on detailed case studies, specific treatment recommendations were developed:
- In cases of oligometastatic pancreatic cancer, the majority of experts recommended local treatment (typically surgery or radiotherapy) in addition to systemic chemotherapy.
- For synchronous oligometastasis, surgical removal of both the primary tumor and metastases was more frequently recommended.
- For metachronous metastases, surgical removal or radiation of the metastases was recommended.
Impact and Future Implications
Oliver Strobel noted that pancreatic cancer is a highly aggressive cancer with a high mortality rate. The newly developed consensus definition allows for a clear identification of patients with an oligometastatic situation.
"This is considered a necessary condition for specifically identifying patients who might benefit from local treatment alongside systemic therapy."
Furthermore, this uniform definition enables the comparison of study results on oligometastatic pancreatic cancer and supports the advancement of specific treatment strategies globally.