Duodenal gangliocytic paraganglioma showing lymph node metastasis: a rare case report

Abstract

We describe a case of duodenal gangliocytic paraganglioma showing lymph node metastasis. A 61-year-old Japanese man underwent pylorus preserving pancreaticoduodenectomy to remove a tumor at the papilla of Vater. The section of the tumor extending from the mucosa to submucosa of the duodenum was sharply demarcated, solid, and white-yellowish. Neither necrosis nor hemorrhage was present. Histological examination confirmed the immunohistochemical identification of three components comprising epithelioid cells, spindle-shaped cells, and ganglion-like cells. Epithelioid cells showed positive reactivity for synaptophysin, somatostatin, and CD56. In contrast, spindle-shaped cells showed positive reactivity for S-100 protein, but not for synaptophysin, somatostatin or CD56. Furthermore, we found lymph node metastasis despite lack of bcl-2 and p53 expression. In addition to the rarity of the tumor, we are describing here the present case suggests the malignant potency of the tumor despite lack of acceptable prognostic indicators for neuroendocrine tumor.

Figure 1

The surgical specimen. (A) A solid tumor measuring 25 × 30 × 25 mm in size was found at the papilla of Vater which was lobulated and covered by attenuated mucosa with ulcer formation at the center of elevation. (B) The section of the tumor extending from the mucosa to submucosa of the duodenum was sharply demarcated, solid, and white-yellowish.

Figure 2

Photomicrographs showing different types of tumor cells. (A) Tumor cells of epithelioid cell type are usually nested which are encompassed by those of spindle-shaped cell type with alignment of a single cell layer (HE double stain, × 400). (B) Ganglion-like cells; third type of the tumor cell had a large and oval nucleus with conspicuous nucleolus, as well as a polyhedral amphophilic cytoplasm (HE double stain, × 1000). (C and D) The metastasizing component of the tumor at the lymph node comprised the epithelioid cell type alone (HE double stain, × 100, × 400, respectively).

Figure 3

Photomicrographs showing representative immunohistochemistry. (A, B, and C) Epithelioid cells showed positive reactivity for synaptophysin, somatostatin, and CD56 (× 400). (D) Spindle-shaped cells showed positive reactivity for S-100 protein (× 400). (E) Tumor cells of both types showed negative reactivity for chromogranin A (× 400). (F) Tumor cells invade into the lymphatic lumen (immunohistochemistry with podoplanin (D2-40) antibody, × 400). (G) Epithelioid cells metastasizing at the lymph node showed positive reactivity for synaptophysin (× 400). (H) No spindle-shaped cells were found in the metastatic focus as confirmed by the lack of S-100 protein-positive cells (× 400).

Figure 4

Photomicrographs showing immunohistochemistry for bcl-2 and p53. (A and B) Tumor cells in primary focus showed negative reactivity for both bcl-2 and p53 (× 400). (C and D) Tumor cells in metastatic focus showed negative reactivity for both bcl-2 and p53 (× 400).