A RARE PANCREATIC NEOPLASM...

In 2014 a 44 years-old lady underwent transabdominal US for mild crampy abdominal pain and loose stools (eventually attributed to IBS). A 1.5 cm lesion in the uncinate process of the pancreas was detected (confirmed by CT). Then she was referred for EUS-FNA. A 13 × 11 mm hypoechoic mass was detected. FNA was performed with a 25G needle (4 passes). Cytology revealed sheets and bundles of spindle cells and immunohistochemistry led to the diagnosis of pancreatic schwannoma (negative staining for desmin, actin, DOG-1 and CD117 and positive for S100) with a low proliferation index (ki67 < 1%). Schwannomas are rare mesenchymal tumors, their origin from the pancreas is exceedingly rare (only 70 cases in literature). Their diagnosis before surgery is difficult, only 17 patients underwent EUS-FNA and the diagnosis could be reached in only 9 cases. To our knowledge, follow-up has been proposed to only 1 patient but the lesion grew up after a 11-month follow-up. After collegial consultation follow-up was proposed to our patient, relying to abdominal US. Four years have passed: the lesion is unchanged and the patient is asymptomatic. We think that a wait-and-see strategy may be proposed for pancreatic schwannomas, provided they are small, stable in size, with a low proliferation index, well-defined margins and without the need for excessive radiation exposure.