Abdominal pain.

HISTORY: A 77-year-old patient with right midabdominal pain.  Rule out appendicitis.

FINDINGS: Image 1 is a transverse scan of the right lobe of the liver

demonstrating a hypoechoic halo around an echogenic lesion in the liver

(arrow).  Notice in Image 2 and 3 that there are multiple periaortic and

porta hepatis lymph nodes.

DIAGNOSIS: Metastatic carcinoma mimicking acute appendicitis.

DISCUSSION: Images of the right lower quadrant were negative in this

patient.  However, upon asking the patient to point with a finger to the

area of maximum tenderness, the patient pointed to her right upper

quadrant.  Scans of the right upper quadrant demonstrated focal liver

lesions in association with lymphadenopathy.  In a 77-year-old patient

the most likely diagnosis is metastatic carcinoma.  Although biopsy was

not obtained, the patient had a prior history of breast carcinoma and

the imaging findings are certainly compatible with that diagnosis.

The clinical diagnosis of acute appendicitis is often imprecise.

Imaging can be useful not only to rule in the diagnosis, but to suggest

an alternative diagnosis when imaging findings are quite compelling for

either pathology.  This patient was spared a laparotomy and, due to her

advanced age, nothing was done other than a CT scan which confirmed the

liver metastases and nodal lesions.