A 58-year-old man from rural Maharashtra presents with a 3-month history of progressive jaundice, pale stools, and dark urine. He reports epigastric pain radiating to the back, worse after meals, and unintentional weight loss of 8 kg. On examination, he is icteric with a palpable gallbladder. Abdominal ultrasound shows dilated intrahepatic bile ducts and a hypoechoic lesion in the pancreatic head measuring 3 cm. CT abdomen with contrast reveals the lesion is hypodense in the arterial phase and shows encasement of the superior mesenteric artery. Serum CA 19-9 is elevated at 280 U/mL (normal <37). What is the most appropriate next step in management?

Explanation

## Clinical Presentation & Diagnosis **Key Point:** In a patient with imaging-confirmed pancreatic cancer (hypoechoic lesion on ultrasound, hypodense on CT), tissue diagnosis via endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) is the standard next step before definitive treatment planning. ## Why EUS-FNA Is Preferred ### Diagnostic Accuracy - EUS-FNA has 85–95% sensitivity for pancreatic masses - Allows real-time visualization and sampling under ultrasound guidance - Can assess local invasion and lymph node involvement simultaneously - Tissue diagnosis is mandatory before committing to surgery or chemotherapy ### Staging & Resectability Assessment | Finding | Implication | |---------|-------------| | Encasement of SMA on CT | Borderline resectable disease | | Hypoechoic lesion 3 cm | Locally advanced | | Elevated CA 19-9 | Supports malignancy but not diagnostic alone | **Clinical Pearl:** The presence of SMA encasement does NOT preclude surgery — it classifies the tumor as "borderline resectable," which may still benefit from neoadjuvant chemotherapy followed by resection if response is adequate. ## Why Other Options Are Premature 1. **Direct surgery without tissue diagnosis:** Violates oncologic principle of histologic confirmation before major surgery; risk of operating on benign mimics (chronic pancreatitis, cystic lesions). 2. **Neoadjuvant chemotherapy without histology:** Chemotherapy is appropriate for borderline/locally advanced disease, but only AFTER tissue confirmation. 3. **Palliative stent alone:** Premature; patient is fit for curative intent therapy and has no metastatic disease on imaging. **High-Yield:** The NCCN and ESMO guidelines mandate tissue diagnosis in all resectable and borderline-resectable pancreatic cancer before treatment initiation. ## Management Algorithm ```mermaid flowchart TD A[Imaging-confirmed pancreatic lesion]:::outcome --> B{Tissue diagnosis obtained?}:::decision B -->|No| C[EUS-FNA]:::action C --> D[Histology confirmed]:::outcome B -->|Yes| E{Metastases present?}:::decision E -->|Yes| F[Palliative chemotherapy]:::action E -->|No| G{Resectable/Borderline?}:::decision G -->|Resectable| H[Proceed to surgery]:::action G -->|Borderline| I[Neoadjuvant chemotherapy]:::action I --> J[Reassess resectability]:::decision J -->|Resectable| H J -->|Unresectable| K[Palliative chemotherapy]:::action ```