Presentation
RIF pain. Fevers and raised inflammatory markers. Appendicitis?
Patient Data
The cecal wall is thickened, enhancing and irregular, and this process also involves the ileocecal junction. with stranding within the surrounding fat. There is also fluid in the right paracolic gutter and mild inflammation of the adjacent colon. The appendix is dilated to 7 mm and appears involved by the tumor. There is upstream small bowel loops dilatation inferring some degree of obstruction. Small lymph nodes within the root of small bowel mesentery.
PATHOLOGY REPORT:
Macroscopy: "Right colon". Right hemicolectomy with terminal ileum and large bowel/cecum. The appendix is adherent to the cecum. Midway through the specimen, within the cecum and at the appendiceal orifice, there is a circumferential and stenosing pale tan lesion measuring 100 (in circumference) x 80 x 20 (depth) mm. The lesion is 50 mm from the proximal margin and 75 mm from the distal resection margin. The lesion extends into mesenteric fat and is 10 mm from the serosal surface. Adjacent to the lesion, within the mesenteric fat, there is a nodular area of varigated tissue (yellow/grey/cream) measuring 60 x 55 x 45 mm which may represent tumor extension. This extends to abut serosal surface and is 5 mm from the surgical mesenteric margin. Within this, there is an area of cream homogenous tissue measuring 6 mm. The appendix appears involved with tumor at the orifice, with the adherent body showing surrounding cream firm tissue. The remainder of mucosa within the small and large bowel appears tan. A total of 15 potential lymph nodes are identified up to 10 mm. Inked green distal margin and black proximal margins, yellow at the mesenteric surgical margin and blue at the serosal surface.
Microscopy: The sections from the macroscopically described tumor show an invasive, poorly differentiated adenocarcinoma with varying morphology. Superficially the tumor is composed of atypical cells with an increased nuclear to cytoplasmic ratio, moderately pleomorphic enlarged nuclei with granular chromatin and nucleoli arranged in compact thin trabeculae. In the deeper aspects, the tumor shows frequent gland formation and is composed of columnar to cuboidal cells with hyperchromatic nuclei. Within these regions, there is abundant mucin production and a broad central area of necrosis. The tumor extensively infiltrates the pericolic tissues and undermines the serosa with a focal serosal breach. Within the cecum, the tumor surroundings the appendiceal orifice with underlying abscess formation surrounding. An isolated tumor nodule is present adjacent to the muscularis propria of the small bowel, however definitive ileal invasion is not identified. There is extensive lymphovascular invasion involving both intramural and extramural veins and perineural invasion is present. The longitudinal and mesenteric resection margins are clear of tumor.
Five lymph nodes are examined, one of which (the macroscopically identified apical node) shows near-complete effacement by adenocarcinoma with abundant mucin production (1/5).
Immunohistochemistry for mismatch repair proteins has been performed and the results are as seen in the synoptic report.
Conclusion: Right colon: Poorly differentiated adenocarcinoma, pT4a N1.
Case Discussion
This case shows a patient presenting with symptoms of appendicitis as his first manifestation of carcinoma of the cecum.