Published online Sep 28, 2020. doi: 10.3748/wjg.v26.i36.5520
Peer-review started: June 11, 2020
First decision: June 18, 2020
Revised: June 29, 2020
Accepted: September 5, 2020
Article in press: September 5, 2020
Published online: September 28, 2020
Processing time: 105 Days and 16.5 Hours
SMARCB1/INI1-deficient pancreatic undifferentiated rhabdoid carcinoma is a very aggressive tumor that is rarely reported in the literature. The tumor has a predominant rhabdoid cell component and different patterns of growth have been reported.
A 59-year-old woman presented with diffuse abdominal pain, increasing in severity and accompanied by weight loss, nausea, and vomiting. Imaging showed a pancreatic head mass. Fine needle aspiration demonstrated atypical epithelioid cells with a pseudopapillary growth pattern suggestive of solid pseudopapillary neoplasm. The excised neoplasm showed monotonous epithelioid and focally spindle cells with pseudopapillary structures, rhabdoid features, and loss of SMARCB1 protein expression with wild-type KRAS, consistent with a SMARCB1/INI1-deficient undifferentiated rhabdoid carcinoma. The patient’s condition deteriorated rapidly following surgery and she expired 3 mo post operation.
In this article, we report the first case of SMARCB1/INI1-deficient undifferentiated pancreatic rhabdoid carcinoma mimicking solid pseudopapillary neoplasm.
Core Tip: The presence of a pseudopapillary architectural pattern in pancreatic tumors sampled via fine needle aspiration commonly leads to solid pseudopapillary neoplasm as the primary diagnostic consideration, particularly in middle-aged women; however, an inconclusive immunohistochemistry profile may suggest an alternative diagnosis. Our case highlights that while SMARCB1/INI1-deficient pancreatic undifferentiated carcinomas may mimic solid pseudopapillary neoplasm, recognition of this aggressive malignancy is important as these rare tumors impart a dismal prognosis.