Pancreatic endocrine tumor with signet ring cell features: a case report with novel ultrastructural observations

Ultrastruct Pathol. Mar-Apr 1998;22(2):147-52. doi: 10.3109/01913129809032270.

Abstract

The case of a malignant pancreatic endocrine neoplasm with an unusual signet ring cell appearance is reported. The tumor was resected from a 30-year-old man with a 4.0-cm tumor in the body of the pancreas diagnosed by computerized tomographic (CT) scan. The resected tumor had a unique morphology characterized by numerous mucin-negative, signet ring cells, which were argyrophilic and immunoreactive for cytokeratin (CAM 5.2), chromogranin, synaptophysin, neuron specific enolase, and gastrin. Dense-core neurosecretory-type granules and numerous cytoplasmic lamellar inclusions were identified by electron microscopy. These inclusion bodies consisted of multilayered concentric osmiophilic lamellae (myelin figures), which most likely represent an abnormal accumulation of degenerating organelles. Two years later, the patient developed an abdominal recurrence of the tumor, confirming its malignant behavior. This case expands the spectrum of pancreatic endocrine tumors to include an aggressive signet ring cell tumor with a novel ultrastructural basis.

Publication types

  • Case Reports

MeSH terms

  • Abdominal Neoplasms / chemistry
  • Abdominal Neoplasms / secondary
  • Adult
  • Biomarkers, Tumor / analysis
  • Carcinoma, Signet Ring Cell / chemistry
  • Carcinoma, Signet Ring Cell / pathology*
  • Carcinoma, Signet Ring Cell / ultrastructure
  • Humans
  • Immunoenzyme Techniques
  • Male
  • Neoplasm Recurrence, Local / chemistry
  • Neoplasm Recurrence, Local / pathology
  • Neuroendocrine Tumors / chemistry
  • Neuroendocrine Tumors / pathology*
  • Neuroendocrine Tumors / ultrastructure
  • Pancreatic Neoplasms / chemistry
  • Pancreatic Neoplasms / pathology*
  • Pancreatic Neoplasms / ultrastructure

Substances

  • Biomarkers, Tumor