Gangliocytic paraganglioma of the appendix with features suggestive of malignancy, a rare case report and review of the literature.

We report a case of appendicial paraganglioma in a 40 year old female who presented with acute appendicitis and underwent laparoscopic appendectomy. To the best of our knowledge this is the first reported case of appendicial gangliocytic paraganglioma with features suggestive of malignancy in the modern literature. Van Eeden S. et al. reported the first case of appendicial paraganglioma in a 47 year old man who also presented with acute appendicitis. The appendectomy specimen showed a distended appendix with thickened wall, and a 1.3 cm mucosal based yellow lesion. Microscopically this lesion was centered in the submucosa and consisted of three different cell types: (a) epithelioid cells with pale eosinophilic finely granular cytoplasm containing bland oval nucleus with stippled chromatin, that form solid nests lying in a trabecular pattern and in formations reminiscent of 'Zellballen' as seen in paragangliomas (b) second type cells have large vesicular nuclei with prominent nucleoli and abundant cytoplasm that are scattered singly, (c) third type cells with bland elongated nuclei form broad fascicle and envelop the epithelioid and ganglion cells. Immunohistochemical analysis showed the epithelioid cell nests immunoreactive for synaptophysin and the ganglion-like cells and spindle Schwann cells to be immunoreactive for S100 protein, whereas all three cells populations were negative for CAM5.2 and Pancytokeratin. We do believe that an accurate diagnosis of Gangliocytic paraganglioma (GP) of the appendix was rendered, detailed microscopic examination of doubled hematoxylin and eosinophil stained sections as well as the immunohistochemical phenotype of the three components have been undertaken to confirm the diagnosis of GP.