Objective:

To explore the differences in ultrasound features between low-grade appendiceal mucinous neoplasm (LAMN) and ovarian mucinous cystadenoma (OMC)

and to provide the basis for distinguishing LAMN from OMC.

Methods:

The medical history data of 35 patients with LAMN confirmed by pathology were retrospectively analyzed

as same as

the medical history data of 40 patients with OMC con

firmed by pathology were retrospectively analyzed. All these patients had been treated surgically in the Obstetrics and Gynecology Hospital of Fudan University from August 2010 to July 2023. The differences in ultrasound features

general data and tumor markers were compared.

Results:

The ultrasound features of LAMN were mostly “Dachshund-like”

with incompletely separated cysts or cysts mixed with substantial components

and the liquid in the cyst was mostly characteristics of “onion skin-like” or “jelly-like”

which could be accompanied by pseudomyxoma peritonei (PMP). Most of the patients’ ages were more than 55 years old

and the levels of carcinoembryonic antigen (CEA)

carbohydrate antigen (CA)19- 9 and CA125 were elevated. The ultrasound features of OMC were mostly round

completely separated cysts or cysts mixed with substantial components. Liquid in the cyst was mostly anechoic or anechoic full of fine spots. Most of them were younger than 50 years old

and the levels of CEA

CA125

and CA19-9 were not significantly elevated.

Conclusion:

There are significant differences between LAMN and OMC in some ultrasound features

such as the shape of neoplasm

the type of septation and the characteristics of cystic fluid

which are expected to be used as markers for distinguishing LAMN from OMC.