CT scans find characteristics of appendiceal mucocele lesions

CT scans can determine characteristics of malignant appendiceal mucocele lesions in patients, aiding in preoperative diagnoses, according to a study published in the October issue of the American Journal of Roentgenology.

Hao Wang, MD, of the Central Hospital of Minhang District in Shanghai, and colleagues designed a study to determine the feasibility of CT use in differentiating malignant from benign lesions in patients with pathologically confirmed appendiceal mucoceles.

Researchers identified 18 patients with pathologically confirmed appendiceal mucoceles through their hospital’s pathology database. Participants included 11 men and seven women who ranged from ages 21-78. Patients were classified into three groups: non-neoplastic mucocele, mucinous cystadenoma and mucinous cystadenocarcinoma. Benign lesions were those in the non-neoplastic mucocele and mucinous cystadenoma groups, while malignant lesions were those classified as mucinous cystadenocarcinoma.

Two experienced radiologists retrospectively reviewed the CT scans of the 18 patients, coming to a consensus about shape, short diameter, density, contour, and wall thickness of masses. The CT results were then compared for malignant and benign appendiceal mucoceles using statistical analysis. The CT showed statistically significant differences in wall irregularity and soft tissue thickening between malignant and benign cases. All other characteristics did not have statistically significant differences.

“We considered the two findings to possibly indicate the infiltrative pattern of malignant mucoceles,” wrote Wang and colleagues. “Although analysis of a larger sample size is needed, the existence of mucocele wall irregularity or soft-tissue thickening may suggest malignancy.”

Despite the two characteristics that enable preoperative diagnoses of malignant mucoceles, the study determined that it is difficult to utilize CT findings to differentiate between benign and malignant lesions.