Although a malignant neoplasm like other cancers, MPNs are classified within the hematological neoplasms. Thyroid adenoma is a benign neoplasm of the thyroid. Less common types include mucinous cystic neoplasm and intraductal papillary biliary neoplasm. Thyroid neoplasm is a neoplasm or tumor of the thyroid. Cysts also may be present due to intraductal papillary mucinous neoplasm. This may be followed by the development of a malignant neoplasm. Melanoma is a type of neuroectodermal neoplasm. The limbus is a common site for the occurrence of corneal epithelial neoplasm. ET is the myeloproliferative neoplasm least likely to progress to acute myeloid leukemia. A secondary hydrocele is secondary to either inflammation or a neoplasm in the testis. Osteoma represents the most common benign neoplasm of the nose and paranasal sinuses. The term "neoplasm" is a synonym of "tumor". A neoplasm is an abnormal growth of cells. A fourth type of cancer that arises in the pancreas is the intraductal tubulopapillary neoplasm.