What is the diagnostic workup for a pancreatic mass?

From the Guidelines

The diagnostic workup for a pancreatic mass should include imaging studies such as computed tomography (CT) or magnetic resonance imaging (MRI) to assess tumor location, size, and extent of disease.

Key Components of Diagnostic Workup

• CT scan: The main modality for diagnosing pancreatic cancer, with technical optimization including multiphase thin-section images and intravenous iodinated non-ionic contrast agent injection 1.
• MRI: Used when CT is inconclusive, such as for isoattenuating tumors or when a contrast-enhanced CT is contraindicated, with recommended sequences including T2-, fat suppressed T1-, and diffusion-weighted sequences 1.
• Endoscopic ultrasound (EUS): Indicated for tumor staging in selected cases, such as isodense tumors at CT or when assessing venous involvement, and can also be used to biopsy the pancreas, lymph nodes, and lesions in the left liver or to sample ascites 1.
• Biopsy: Indicated for patients requiring differential diagnosis with benign chronic pancreatitis or a histological diagnosis, with EUS-guided fine-needle biopsy preferred over CT-guided biopsy for localized disease 1.
• Chest CT or x-ray: Recommended as part of the preoperative workup to evaluate for pulmonary metastases 1.
• CA 19-9: A tumor marker that can be used to support a diagnosis of pancreatic cancer, although not specific or sensitive enough for screening or diagnosis 1.

Additional Considerations

• Multidisciplinary review: Involving expertise from diagnostic imaging, interventional endoscopy, medical oncology, radiation oncology, surgery, and pathology to discuss the patient's case and determine the best course of action 1.
• Staging laparoscopy: May be considered to evaluate peritoneal metastasis in resectable or borderline resectable pancreatic cancer, although not routinely carried out 1.
• PET-CT: Not routinely recommended for the diagnosis of pancreatic cancer, but may be considered for staging in the presence of non-metastatic disease on CT for patients who will receive local cancer treatment 1.

From the Research

Diagnostic Workup for Pancreatic Mass

The diagnostic workup for a pancreatic mass involves a combination of clinical evaluation, imaging techniques, and operative procedures.

• The initial step is to analyze the patient's symptoms and presentation, as a solid pancreatic mass can be both asymptomatic or symptomatic 2.
• Imaging techniques such as computed tomography (CT) scan, ultrasound, and endoscopic retrograde cholangiopancreatography (ERCP) are commonly used in the diagnostic workup 3.
• A helical CT scan provides the best overall assessment of patients with periampullary malignancies and is often the only test required 3.
• If the patient's history and blood test abnormalities suggest pancreatic carcinoma and the helical CT scan shows a mass in the head of the pancreas that appears to be resectable, the patient should be prepared for surgery 3.
• Fine-needle aspiration (FNA) for cytology should be performed if microscopic proof of the diagnosis will avoid surgery 3.
• Endoscopic ultrasonography (EUS)-guided FNA is an important aspect in the diagnosis and management of pancreatic masses, with an overall accuracy ranging between 71% and 90% 4.
• The choice of needle may depend on the location and size of the lesion, and factors that may increase the diagnostic yield of FNA include sampling the lesion in multiple planes and targeting the margins or firmer ends of a necrotic mass 4.

Diagnostic Algorithm

A diagnostic algorithm for the evaluation of pancreatic lesions can be structured in broad terms of solid versus cystic lesions 5.

• EUS FNA of pancreatic masses is becoming the standard for obtaining cytological diagnosis, as it avoids the risk of cutaneous or peritoneal contamination and is less invasive than surgical interventions 5.
• The main goal of surgical indication is to select patients with suspected malignancy who are resectable, but avoid unnecessary resections 6.
• Biopsy is indicated in selected patients, and about 5% of patients resected due to suspicion of malignancy finally present with a benign histology, with autoimmune pancreatitis being the most frequent cause of such unnecessary resections 6.