Presentation
Acute abdominal pain, localizing to the right iliac fossa. No relevant prior medical history.
Patient Data
The appendix is dilated and thick walled, with surrounding stranding in keeping with acute appendicitis. Moderate surrounding inflammatory change, with no extraluminal gas or collection.
At the base of the appendix in the cecum, there is a hyperdense mass. Pericaecal fat stranding is also demonstrated. Enlarged ileocecal lymph nodes are present.
In the right liver there is a hypodense lesion.
Conclusion:
Suspected cecal cancer obstructing the appendiceal orifice, with acute appendicitis. Right liver hypodense lesion in this context is suspicious for a metastasis. MRI liver is suggested for further evaluation and to identify any other metastases.
Segment 7/8 lesion identified on previous CT demonstrates intense high T2 signal, high signal on high b-value DWI and progressive peripheral nodular enhancement from the arterial to venous phases. There is no uptake of Primovist in this lesion.
A further small arterially hyperenhancing lesion is demonstrated in segment 3, with persisting enhancement into the venous phases and no uptake of Primovist.
These are both likely hemangiomas.
Case Discussion
Cecal adenocarcinoma was confirmed on the surgical specimen.
Acute appendicitis is a very common presentation to ED. The usual cause is some form of luminal obstruction, which is most commonly from a fecolith/appendicolith. Less common causes include parasites (e.g. Ascaris), gallstones and tumor. It is imperative that appendicitis in an older population not be dismissed as once in a while you will come across a case such as this, with an obstructing cecal carcinoma. This also has important implications for the surgeon, who will change the surgical approach (to prepare for a right hemicolectomy) if alerted to the possibility of an underlying tumor.
In staging, CT is still the mainstay modality. For liver metastases however, Primovist MRI is much more sensitive, and its role is more in the detection of small lesions, as this has treatment implications (e.g. resection, ablation or systemic therapy).