I've been thinking about this case for a while now, and would like to offer some of my thoughts. First of all, was the appendiceal tumor circumscribed and entirely excised? How large was it? Was the lymph node positive for metastasis? Finding "signet ring" neoplastic cells in an appendiceal tumor raises three possibilities: (1) adenocarcinoid tumor of appendix; (2) poorly differentiated adenocarcinoma of appendix; and (3) metastatic adenocarcinoma (from stomach or elsewhere in the gastrointestinal tract). Immunohistochemical stains for neuroendocrine markers (NSE, synaptophysin, chromogranin and CD56) help in the diagnosis of appendiceal adenocarcinoid tumor, which may still be cured by appendectomy if the entire tumor is smaller than 2 cm, circumscribed, and does not breach the serosal surface or involve the appendiceal and mesoappendiceal resection margins. If the adenocarcinoid tumor is circumscribed but larger than 2 cm, a right colectomy is indicated and if there is no regional lymph node metastasis it is still curable. However, if the lesion is large and infiltrative with destructive growth it is probably an adenocarcinoma even if some cells display immunoreactivity to various neuroendocrine markers. Importantly, careful oncologic workup (upper and lower GI endoscopy, CA19-9 level, CEA level, abdominal (including liver and pancreas) CT scans or MRI) should be done before further management is planned and executed. I hope, for the young boy's and his family's sake, that he had in fact a small adenocarcinoid at the appendiceal tip and it is entirely excised during appendectomy.
I've been thinking about this case for a while now, and would like to offer some of my thoughts. First of all, was the appendiceal tumor circumscribed and entirely excised? How large was it? Was the lymph node positive for metastasis? Finding "signet ring" neoplastic cells in an appendiceal tumor raises three possibilities: (1) adenocarcinoid tumor of appendix; (2) poorly differentiated adenocarcinoma of appendix; and (3) metastatic adenocarcinoma (from stomach or elsewhere in the gastrointestinal tract). Immunohistochemical stains for neuroendocrine markers (NSE, synaptophysin, chromogranin and CD56) help in the diagnosis of appendiceal adenocarcinoid tumor, which may still be cured by appendectomy if the entire tumor is smaller than 2 cm, circumscribed, and does not breach the serosal surface or involve the appendiceal and mesoappendiceal resection margins. If the adenocarcinoid tumor is circumscribed but larger than 2 cm, a right colectomy is indicated and if there is no regional lymph node metastasis it is still curable. However, if the lesion is large and infiltrative with destructive growth it is probably an adenocarcinoma even if some cells display immunoreactivity to various neuroendocrine markers. Importantly, careful oncologic workup (upper and lower GI endoscopy, CA19-9 level, CEA level, abdominal (including liver and pancreas) CT scans or MRI) should be done before further management is planned and executed. I hope, for the young boy's and his family's sake, that he had in fact a small adenocarcinoid at the appendiceal tip and it is entirely excised during appendectomy.