What is the initial workup for a suspected pancreatic mass?

Initial Workup of Pancreatic Mass

For any patient with suspected pancreatic cancer, immediately order a dedicated pancreas protocol CT scan with intravenous contrast as your primary imaging modality—this is the gold standard recommended by the National Comprehensive Cancer Network and achieves 70-85% accuracy in predicting resectability while providing critical vascular assessment. 1, 2

Primary Imaging: Pancreas Protocol CT

The pancreas protocol CT is non-negotiable and must include specific technical parameters:

• Dual-phase contrast-enhanced imaging with late arterial/pancreatic phase (40-50 seconds post-contrast) and portal venous phase (70 seconds post-contrast) 1, 2
• Thin-slice acquisition using submillimeter axial sections with multiplanar reformations 1, 2
• Chest imaging included to evaluate for pulmonary metastases 1

This protocol provides 89-97% sensitivity for detecting pancreatic cancer and allows assessment of critical vascular structures (celiac axis, superior mesenteric artery, superior mesenteric vein, portal vein, splenic vein) to determine resectability 2, 3, 4

When CT Cannot Be Performed

If IV contrast is contraindicated (allergy, renal insufficiency), order MRI with gadolinium and MRCP as the preferred alternative. 5, 1, 2

• MRI offers superior soft-tissue contrast and better characterization of liver lesions 1, 2
• MRI detects liver metastases not visible on CT in 10-23% of cases 2
• MRI with MRCP has 96.8% sensitivity and 90.8% specificity for distinguishing pancreatic lesions, compared to 80.6% and 86.4% for CT 5
• MRI is superior for detecting isoattenuating tumors (5-17% of pancreatic cancers) 2

Essential Laboratory Evaluation

Order these baseline labs immediately:

• Liver function tests (AST, ALT, alkaline phosphatase, total/direct bilirubin) to assess biliary obstruction 1
• CA 19-9 tumor marker for baseline and monitoring 1
• Fasting glucose or HbA1c (new-onset diabetes in patients ≥50 years may indicate pancreatic cancer) 5, 1
• Lipase or amylase 1

Tissue Diagnosis Strategy

The timing of tissue diagnosis depends entirely on resectability assessment from imaging:

• For resectable disease: Proceed directly to surgical consultation without tissue diagnosis—do not delay surgery for biopsy 1
• For borderline resectable or unresectable disease: Obtain tissue via EUS-guided fine needle aspiration (EUS-FNA) 1
• For metastatic disease: Tissue diagnosis is mandatory before initiating systemic therapy 1

Critical pitfall: Transperitoneal biopsy (CT-guided or ultrasound-guided) carries risk of tumor seeding and false negatives; approximately 5% of pancreaticoduodenectomies reveal benign disease, which is acceptable given low surgical mortality 5

Role of Endoscopic Ultrasound (EUS)

EUS is complementary to CT, not a replacement, and should be used selectively:

• When CT shows no lesion despite high clinical suspicion 2
• When questionable vascular or lymph node involvement is present 2
• For tissue acquisition in unresectable disease (EUS-FNA preferred over CT-guided biopsy) 2
• EUS has 98% sensitivity for detecting small tumors <2 cm 6

Do not use EUS-FNA for initial characterization of small pancreatic cysts (<2.5 cm) as the risk of malignant transformation is extremely low and procedural risks may outweigh benefits 5

Performance Status Assessment

Document baseline ECOG performance status and comorbidity profile—this directly impacts treatment eligibility:

• ECOG 0-1 patients with favorable comorbidities are candidates for aggressive regimens like FOLFIRINOX 1
• Performance status determines surgical candidacy and chemotherapy tolerance 1

PET/CT Considerations

PET/CT is not routinely recommended for initial diagnosis but may be considered:

• After formal pancreas protocol CT in high-risk patients to detect occult metastases 2
• For staging in non-metastatic disease when local treatment is planned 2
• FDG-PET has 71-100% sensitivity and 64-90% specificity but does not replace morphologic imaging 3

Common Pitfalls to Avoid

• Never delay pancreas protocol CT for basic ultrasound—while ultrasound may be the first test ordered for abdominal pain/jaundice, it has only 50-70% accuracy for pancreatic tumors 3
• Do not obtain tissue diagnosis for resectable disease—this delays curative surgery and risks false negatives 5, 1
• Recognize that 5-17% of pancreatic cancers are isoattenuating and may be missed on standard CT; consider MRI if clinical suspicion remains high despite negative CT 2
• Remember that chronic pancreatitis can mimic pancreatic cancer—both conditions may coexist, potentially leading to staging overestimation 3