title: Primary ovarian carcinoid tumor showing unusual histology and nuclear accumulation of β-catenin.
abstract: Carcinoid tumor of the ovary is uncommon. We herein report a very rare case of primary ovarian carcinoid tumor with aggressive histology and an unusual immunophenotype. A 21-year-old woman presented with a palpable abdominal mass. Computed tomographic scan revealed a large, extensively necrotic solid mass in the left ovary. The patient underwent a left salpingo-oophorectomy. Grossly, the left adnexa showed a large, vaguely lobulated ovarian tumor measuring 22×15×13 cm. Histologically, the tumor had a readily identifiable neuroendocrine growth pattern, but some areas showed solid growth pattern associated with mild nuclear pleomorphism and multiple foci of punctate necrosis. Furthermore, mitotic figures were recognized in 8 per 10 high-power fields, and a few foci of large coagulative tumor necrosis were also noted. In addition, the tumor tissue exhibited uniform, strong nuclear β-catenin immunoreactivity, indicating the nuclear accumulation of β-catenin in the individual tumor cells. In summary, we described the first case of primary ovarian carcinoid tumor with loss of neuroendocrine growth pattern, increased mitotic activity and large areas of coagulative tumor necrosis. According to the WHO classification of pulmonary carcinoid tumor, this case may be classified as "atypical" carcinoid. However, currently, no primary ovarian atypical carcinoid exists in the classification system. Due to its rarity, there are no established diagnostic criteria and clinical data on patient outcomes for ovarian carcinoid tumors with aggressive histology. Additional reports are clearly necessary. We also showed for the first time the nuclear accumulation of β-catenin in carcinoid tumor cells, suggestive of a role for β-catenin in the tumorigenesis of ovarian atypical carcinoid tumor or its aggressive histology.
authors.affiliation: Department of Pathology, Severance Hospital, Yonsei University College of Medicine Seoul, Republic of Korea.
authors.forename: Hyun-Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Gynecology and Obstetrics, Pusan National University Yangsan Hospital, Pusan National University School of Medicine Yangsan, Republic of Korea.
authors.forename: Gun
authors.initials: G
authors.lastname: Yoon
authors.affiliation: Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine Seoul, Republic of Korea.
authors.forename: Hye-In
authors.initials: HI
authors.lastname: Jang
authors.affiliation: Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine Seoul, Republic of Korea.
authors.forename: Sang Yong
authors.initials: SY
authors.lastname: Song
authors.affiliation: Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine Seoul, Republic of Korea.
authors.forename: Byoung-Gie
authors.initials: BG
authors.lastname: Kim
mesh_terms: D002276:Carcinoid Tumor / Q000378:metabolism / Q000473:pathology*; D002467:Cell Nucleus / Q000378:metabolism; D005260:Female; D006801:Humans; D010051:Ovarian Neoplasms / Q000378:metabolism / Q000473:pathology*; D055815:Young Adult; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D051176:beta Catenin
keywords: Neuroendocrine tumor; atypical carcinoid; carcinoid; ovary