The CT findings are those of a solid appendiceal tumor, with differential diagnosis including an adenocarcinoma or neuroendocrine tumor. Lymphoma and mucinous neoplasms were considered less likely given the focal solid enhancing pattern of the lesion. 

This patient underwent right hemicolectomy with further confirmation of a pT3 N0 Mx Goblet cell carcinoid of the appendix, likely in the category signet ring cell type (Group B) of Goblet cell carcinoid.  

The WHO classification of tumors states that Gobled cell carcinoid tumor exhibits both neuroendocrine and glandular differentiation, but is a distinct epithelial tumor from classic neuroendocrine carcinoma or adenocarcinoma. As you can imagine, this can pose a challenge to pathologists in classifying the tumor.