SMARCB1/INI1-deficient pancreatic undifferentiated rhabdoid carcinoma mimicking solid pseudopapillary neoplasm: A case report and review of the literature

Abstract

BACKGROUND 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. CASE SUMMARY 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. CONCLUSION In this article, we report the first case of SMARCB1/INI1-deficient undifferentiated pancreatic rhabdoid carcinoma mimicking solid pseudopapillary neoplasm.

SMARCB1/INI1‐deficient undifferentiated pancreatic carcinoma in a 13‐year‐old male patient: A case report

“…Undifferentiated pancreatic carcinoma (UPC) accounts for 2%-7% of all pancreatic cancers and includes a spectrum of histologic variants such as anaplastic rhabdoid carcinoma, sarcomatoid spindle cell carcinoma, carcinosarcoma with recognizable adenocarcinoma and high-grade spindle cell areas, and undifferentiated carcinoma with osteoclast-like giant cells. 3 4 SIDUPC was designated as a unique subset of undifferentiated pancreatic carcinoma in the 5th edition of the WHO classification of digestive system tumors in 2019 1 and characterized by aggressive biological behaviors, rhabdoid morphology, and a unique immunohistochemical and genetic phenotype. Fourteen SIDUPC (including our case) cases have been reported; however, only 11 cases had detailed clinical and pathological data.…”

“…Fourteen SIDUPC (including our case) cases have been reported; however, only 11 cases had detailed clinical and pathological data. [3][4][5][6][7][8][9][10][11] The male to female sex ratio for these 11 patients was 5:6, and the age range was 13-76 years (average, 52.5 years), with our patient being the youngest. Maximum tumor diameter ranged 1.6-10 cm (average, 4.9 cm).…”

“…[3][4][5][6][7][8][9][10][11] Seven patients had specified distant metastases at initial admission, with the liver being the most common metastatic site (6/7). 3 Rhabdoid pattern is the most common histological feature of SIDUPC (11/11); however, its proportion is variable in the tumors. [3][4][5][6][7][8][9][10][11] No standard therapy has been established for SIDUPC.…”

“…3 Rhabdoid pattern is the most common histological feature of SIDUPC (11/11); however, its proportion is variable in the tumors. [3][4][5][6][7][8][9][10][11] No standard therapy has been established for SIDUPC. Surgical resection is still the primary treatment for this tumor; however, radical resection is usually unachievable in these patients because of the advanced stage at first presentation, its quick progression, and disseminated metastases.…”

Extended pancreato-duodenectomy coupled with adjuvant chemotherapy for SMARCB1/INI1 deficient pancreatic carcinoma: A case report and literature review

“…SMARCB1 and related proteins is involved in tumor proliferation and progression through a variety of pathways such as the WNT signaling and p16-RB pathways [ 1 , 24 ]. Although the role of SMARCB1 remains largely unknown, it has been reported to play a role in certain neoplasms including esophageal, renal medullary, pleura and pancreatic carcinoma [ 2 , [17] , [18] , [19] , [20] , [21] , [22] , [23] ]. Deficiency of SMARCB1/INI1 appears to be generally associated atypical rhabdoid/teratoid neoplasms.…”