A Rare Case of Rhabdoid Pancreatic Carcinoma: Prolonged Disease-Free Survival Following Upfront Resection and Adjuvant Chemotherapy

Abstract

The rhabdoid subtype of undifferentiated pancreatic carcinoma is rarely reported. The clinical course of this disease is therefore poorly understood, although it is apparently an aggressive malignancy. We herein discuss the case of a 69-year-old man presenting with a rapidly enlarging mass of the pancreatic body and tail who was diagnosed with locally advanced SMARCB1-deficient undifferentiated pancreatic carcinoma with rhabdoid features, treated with radical resection and adjuvant chemotherapy, and has achieved 18-month disease-free survival ongoing at the time of article publication. We identify and contrast our case with 15 similar tumors reported in the English literature, briefly discuss the biology of this tumor, its relationship to malignant rhabdoid tumors of childhood, the role of SMARCB1 and its parent complex switch/sucrose-non-fermentable chromatin remodeling complex (SWI/SNF) in modulating the behavior of pancreatic malignancy, and the potential therapeutic avenues available for SWI/SNF-mutated malignancies.

Keywords: baf47; ini1; pancreas; pancreatic cancer; rhabdoid; sarcomatoid; smarcb1; swi/snf; switch/sucrose non-fermentable; undifferentiated pancreatic cancer.

Figure 1. (A) axial and (B) coronal slices of CT at admission, demonstrating 50 x 59 mm (axial) mass of pancreatic body and tail.

The tumor encased the splenic artery and was associated with pathological left gastric lymph nodes measuring up to 11 mm.

Figure 2. Tumor histopathology.

(A) High-power magnification (H&E, 400x) demonstrating sheets of discohesive, pleomorphic, rhabdoid tumor cells including multinucleated forms and necrosis. (B) Low power magnification (H&E, 40x) showing invasion of tumor into a large vein. (C) Tumor cells were strongly positive for MNF116 pan-cytokeratin immunohistochemical stain (200x). (D) Tumor cells showed abnormal loss of nuclear staining for INI1, with retained staining in admixed inflammatory cells (positive internal control, 400x).