Pancreatic cystic neoplasms

Pancreatic cystic neoplasms are a group of tumors with varying malignant potential. Intraductal papillary mucinous neoplasms (IPMNs) are mucin-producing tumors with malignant potential that arise from the pancreatic duct epithelium; malignant potential varies. Mucinous cystic neoplasms (MCNs) are also mucin-secreting tumors with malignant potential that almost exclusively affect women > 40 years of age and are defined by a subepithelial ovarian-type stroma. Serous cystadenomas are benign tumors with an extremely low risk of malignant transformation that are also more common in women. Pancreatic cystic neoplasms are often found incidentally. Diagnosis involves imaging (e.g., MRI, MRCP) and endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) for cyst fluid analysis; elevated CEA levels suggest a mucinous cyst (e.g., an IPMN or MCN). Management is based on the type of neoplasm. Surgical resection is recommended for branch duct IPMNs with high-risk features, main duct and mixed-type IPMNs, and often for MCNs. Postoperative surveillance is required for resected IPMNs due to the risk of recurrence and concomitant pancreatic cancer. Asymptomatic serous cystadenomas typically do not require treatment.

• Definition: a neoplasm that arises from the epithelial cells of the pancreatic ducts and is the most common pancreatic cystic neoplasm ^[3][4]
• Epidemiology
  • Sex: ♂ = ♀ ^[1]
  • Age of onset: typically 60–69 years ^[1]
  • 40% of IPMNs are multifocal. ^[1][2]
• Clinical features ^[1][2]
  • Often asymptomatic
  • Abdominal pain
  • Acute pancreatitis
• Diagnosis ^[1][2]
  • First line: MRI or MRCP
  • Second line: Pancreatic protocol CT or EUS
  • EUS with FNA if diagnosis is unclear and results would alter management ^[1]
• Management
  • Consider surgical resection for IPMN with high malignancy risk (e.g., main duct involvement). ^[2][2]
  • Surveillance intervals for presumed IPMN
    • < 1 cm: MRI or MRCP every 2 years for 4 years ^[1]
    • 1–2 cm: MRI or MRCP annually for 3 years, then every 2 years for 4 years if stable ^[1]
    • 2–3 cm: MRI or EUS every 6–12 months for 3 years, then annually for 4 years if stable ^[1]

• Definition: mucin-secreting neoplasms with malignant potential ^[2]
• Epidemiology
  • Sex: almost exclusively ♀ ^[1][2]
  • Age of onset: typically 40–69 years ^[1]
• Diagnosis
  • Typical findings on CT or MRI include: ^[1][2]
    • Unilocular, thick-walled cyst
    • No communication with the main pancreatic duct
  • EUS with FNA if diagnosis is unclear and results would alter management
    • Carcinoembryonic antigen levels: often elevated ^[1]
    • Subepithelial ovarian-type stroma: definitive histopathological feature ^[2]
• Management
  • Consider surgical resection in patients with any of the following: ^[1]
    • Jaundice or acute pancreatitis secondary to the cyst
    • Significantly elevated serum CA 19-9
    • Presence of a mural nodule or solid component
    • Cyst size ≥ 3 cm^[1]
    • Rapid increase in cyst size (≥ 3 mm/year) ^[1]
  • Surveillance intervals for presumed MCN
    • < 1 cm: MRI or MRCP every 2 years for 4 years ^[1]
    • 1–2 cm: MRI or MRCP annually for 3 years, then every 2 years for 4 years if stable size and appearance ^[1]
    • 2–3 cm: MRI or EUS every 6–12 months for 3 years, then annually for 4 years if stable ^[1]

Surgical resection of a noninvasive MCN is curative. ^[2]

• Definition: a pancreatic tumor with an extremely low risk of malignant transformation. ^[2]
• Epidemiology
  • Sex: ♀ > ♂ (approx. 3:1) ^[1]
  • Age of onset: typically 40–59 years ^[1][2]
• Clinical features ^[1][2]
  • Typically asymptomatic
  • Symptoms can occur due to mass effect.
• Diagnosis ^[1][2]
  • Cross-sectional imaging: microcystic or honeycomb appearance
  • Atypical imaging findings (e.g., macrocystic appearance): Order EUS with FNA to confirm diagnosis.
• Management
  • Asymptomatic serous cystadenomas with classic imaging features do not require treatment or surveillance. ^[1]
  • Consider surgical resection for symptomatic serous cystadenomas. ^[2]