Joshua D. McCarron, MD1, Zachary Neubert, DO1, Angela Bachmann, MD1, Chris Costanza, MD2; 1Naval Medical Center, San Diego, CA; 2Southern California Permanente Medical Group, San Diego, CA
Introduction: Goblet cell adenocarcinoma (GCA) is a rare, aggressive form of malignancy possessing features of both a neuroendocrine tumor and adenocarcinoma. Typical presentation is in the setting of appendicitis, abdominal pain, and diarrhea. We present a 51-year-old patient diagnosed after diagnostic colonoscopy for two-month history of diarrhea.
Methods: A 51-year-old Hispanic male presented for diagnostic colonoscopy after a two-month history of watery diarrhea. Vital signs, physical exam, blood counts and electrolytes were unremarkable. Colonoscopy performed revealed subtle granular mucosa in the appendiceal orifice without an obvious mass (Fig. 1). Biopsies with cold forceps of the appendiceal orifice and overlying mucosa revealed appendiceal GCA. Computed tomography with IV contrast revealed a dilated appendix (Fig. 2). Surgical evaluation obtained and patient underwent an uncomplicated right-hemicolectomy. A 3 cm tumor invading the visceral peritoneum was excised with negative margins and no evidence of lymph node involvement. Pathology revealed a well-differentiated, mixed GCA (adenocarcinoma ex goblet cell carcinoid) (Fig. 3). Final evaluation denoted stage IIb GCA, which is high risk based on his T4aN0 classification. Medical oncology started the patient on adjuvant chemotherapy with oxaliplatin and capecitabine. Presently, the patient has completed adjuvant chemotherapy without evidence of recurrent disease. Discussion: GCA is a rare malignancy combining the characteristics of neuroendocrine tumors and adenocarcinoma, comprising 13.8% of all primary appendiceal neoplasms with an annual incidence of just 0.017 cases per million patient years. Most patients present with symptoms suggestive of acute appendicitis (acute right lower quadrant abdominal pain, nausea, vomiting, diarrhea, and a palpable abdominal mass) as the appendix is the most common organ afflicted. Given the rarity of this condition, no consensus guidelines exist for its management. Most often, treatment mirrors that of typical adenocarcinomas. Surgical resection is the primary treatment and can be limited to appendectomy if considered stage I. In higher stages, as demonstrated in this case, right hemicolectomy is performed to obtain adequate nodal sampling as metastasis is common. Adjuvant chemotherapy is also recommended in select cases. We present a case of appendiceal goblet cell adenocarcinoma presenting with diarrhea diagnosed by colonoscopy and managed with right hemicolectomy, and adjuvant chemotherapy.
Figure 1. Appendiceal orifice with subtle granular mucosa.
Figure 2. Computed tomography with intravenous contrast of the abdomen showing dilated appendix (green arrow).
Figure 3. The tumor is composed of goblet-like mucinous cells growing in small cohesive groups that lack lumina (example with black arrow). Nuclear atypia is mild and there are infrequent mitoses. (Hematoxylin and eosin stain, 100x).
Disclosures: Joshua McCarron indicated no relevant financial relationships. Zachary Neubert indicated no relevant financial relationships. Angela Bachmann indicated no relevant financial relationships. Chris Costanza indicated no relevant financial relationships.