Figure 2.

LAMN. Axial T2-weighted MRI sequence (A) and gadolinium contrast-enhanced sagittal T1-weighted MRI sequence with fat suppression (B), showing a mucocele of the appendix (white arrow in A), measuring 8.6 cm at its maximum longitudinal diameter. Solid parietal nodules (arrowheads in B) are noted, the largest measuring 8 mm, a feature that is suggestive of malignancy. A small suspected point of rupture is seen anteriorly (curved arrow in A). C: Gross specimen obtained by appendectomy with partial resection of the cecum, measuring 9 cm in length and 4 cm at its maximum diameter. On cross-section, the appendiceal lumen is markedly distended by an abundant translucent, yellowish-white viscous content (arrow), with three luminous projections, each measuring less than 1 cm. The surface has a 1-cm focus of rupture. D: Replacement of the normal colonic epithelium by a monolayer of cytologically bland mucinous epithelium (arrow). The lymphoid tissue of the appendix is absent, and there is subepithelial fibrosis and calcifications ({), the tumour showing a broad pushing border (haematoxylin and eosin; magnification, ×25). The final histopathologic diagnosis was LAMN.