The case was diagnosed as right benign seromucinous cystadenoma.

Ovarian neoplasms can be divided into epithelial tumors, germ cell tumors, sex cord-stromal tumors, and metastatic tumors.

Epithelial tumor is the most common one and represents about 60% of all ovarian tumors.

Serous and mucinous cystadenomas are the commonest type of ovarian epithelial neoplasm. The peak incidence is at the 4th to 5th decades of life.

Serous cystadenoma tends to uni-locular and smaller than the mucinous cystadenoma.

Homogenous internal contents, thin regular walls and septae, and absence of soft tissue components favor benign nature.