What are the diagnostic criteria for pancreatic ductal adenocarcinoma (PDAC)?

From the Guidelines

Diagnosing pancreatic ductal adenocarcinoma (PDAC) requires a comprehensive approach combining imaging, laboratory tests, and tissue sampling, with contrast-enhanced CT scan of the abdomen as the first-line imaging modality, as recommended by the most recent guidelines 1. The diagnostic criteria for PDAC involve a combination of imaging modalities, laboratory tests, and tissue sampling.

• Initial evaluation should include contrast-enhanced CT scan of the abdomen with pancreas protocol that includes arterial and venous phases to assess tumor characteristics and vascular involvement, as stated in the guidelines 1.
• Endoscopic ultrasound (EUS) with fine-needle aspiration or biopsy is recommended for tissue diagnosis, particularly for lesions smaller than 2 cm or when CT findings are inconclusive, as suggested by the evidence 1.
• Laboratory tests should include serum CA 19-9, which may be elevated in PDAC but lacks specificity, along with liver function tests and complete blood count, as mentioned in the guidelines 1.
• Magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) provides additional characterization of pancreatic lesions and bile duct involvement, as recommended by the guidelines 1.
• For patients with jaundice, endoscopic retrograde cholangiopancreatography (ERCP) may be performed for both diagnostic and therapeutic purposes, as stated in the evidence 1.
• Staging should follow the TNM classification system to determine resectability and treatment planning, as suggested by the guidelines 1.
• Genetic testing for germline mutations (BRCA1/2, PALB2) should be considered, especially in patients with family history of pancreatic cancer, as recommended by the guidelines 1. The most recent and highest quality study 1 prioritizes the use of contrast-enhanced CT scan and MRI for primary staging, with EUS and FDG-PET/CT as useful problem-solving techniques for biopsy guidance and confirmation of distant metastases.
• The study also emphasizes the importance of detailed reporting of vascular involvement, tumor size, and location, as these factors are crucial in determining resectability and treatment planning, as stated in the guidelines 1. The use of contrast-enhanced CT scan and MRI, along with laboratory tests and tissue sampling, provides a comprehensive approach to diagnosing PDAC, and is supported by the most recent and highest quality evidence 1.

From the Research

Diagnostic Criteria for Pancreatic Ductal Adenocarcinoma (PDAC)

The diagnostic criteria for PDAC involve various imaging tests and techniques to assess the resectability, staging, and treatment options for patients. The key diagnostic criteria include:

• Imaging tests such as CT, MRI, and PET/CT to evaluate the tumor size, location, and involvement of surrounding tissues and organs 2
• Assessment of tumor involvement of arteries and veins to determine resectability criteria, as defined by the National Comprehensive Cancer Network (NCCN) guidelines 2
• Evaluation of lymph node metastases, liver and peritoneal metastases, and disease restaging following neoadjuvant therapy 2
• Use of endoscopic ultrasonography (EUS) and endoscopic retrograde cholangiopancreatography (ERCP)-associated pancreatic juice cytology for preoperative pathological diagnosis 3
• Consideration of indirect imaging findings, such as main pancreatic duct stenosis on MRI, to detect early-stage PDAC 3

Imaging Techniques and Advances

Imaging techniques play a crucial role in the diagnosis and staging of PDAC. The preferred modality is CT, due to its wider availability, greater consistency in image quality, and lower cost 2. MRI and PET/CT are usually reserved as problem-solving tools in select patients. Artificial intelligence (AI) has the potential to improve the accuracy of staging and detection of small early-stage tumors, and may also provide imaging biomarkers to predict disease recurrence and patient survival 2.

Diagnostic Algorithm and Proposal

A new diagnostic algorithm based on tumor size and imaging findings has been proposed to improve the early diagnosis of PDAC 3. This algorithm emphasizes the importance of identifying asymptomatic patients, close examinations of indirect imaging findings, and standardization of preoperative pathological diagnosis. The use of EUS-guided fine-needle aspiration and ERCP-associated pancreatic juice cytology can also improve the sensitivity of preoperative pathological diagnosis 3.

Current Status and Future Directions

Recent advances in the understanding of PDAC biology have revealed new opportunities for early detection and targeted therapy 4. The current status of surveillance and early detection of PDAC, including populations at high risk and screening approaches, is being reviewed and updated 4. The diagnostic approach to PDAC and treatment considerations, including disease stage and targetable subtypes, are also being refined 4.