title: Rapid growth of mitotically active cellular fibroma of the ovary: a case report and review of the literature.
abstract: BACKGROUND
  Mitotically active cellular fibroma (MACF) of the ovary, characterized by relatively high mitotic activity without severe atypia, represents a relatively new disease entity. MACF is categorized as a benign ovarian tumor. However, due to a limited number of case reports, its clinical and pathological features and optimum management remains largely undetermined. Herein, we report on a rare case of MACF that grew rapidly in size and was diagnosed on detailed pathological examination.
  
  
  METHODS
  A 44-year-old Japanese woman, who detected a myoma-like lesion 1-year earlier, was referred to our hospital when the follow-up examination demonstrated that the mass had increased in size. Magnetic resonance imaging revealed a T1 isointense and T2 hyperintense tumor (11 cm in diameter) in the right pelvic cavity. Laparoscopy confirmed the presence of a right ovarian tumor and laparoscopic right adnexectomy was performed. The tumor cells consisted of dense cellular proliferations of spindle fibroblast-like cells without significant cytological atypia. The mitotic activity index was estimated at >15 mitotic figures per 10 high-power fields. Reticulin staining and FOXL2 mutation analysis excluded the possibility of an adult granulosa cell tumor, and the patient was diagnosed with a MACF of the ovary.
  
  
  CONCLUSIONS
  To the best of our knowledge, we are the first to report on a case of rapid growth of a MACF of the ovary during follow-up. When an increase in the size of a solid ovarian mass is detected, a MACF should be considered as a differential diagnosis.
authors: Departments of Tumor and Diagnostic Pathology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan. katsuya@nagasaki-u.ac.jp.
authors: Katsuya
authors: K
authors: Matsuda
authors: Department of Obstetrics and Gynecology, Japan Community Health Care Organization, Isahaya General Hospital, Isahaya, Japan.
authors: Seiko
authors: S
authors: Tateishi
authors: Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
authors: Yuko
authors: Y
authors: Akazawa
authors: Department of Human Genetics, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan.
authors: Akira
authors: A
authors: Kinoshita
authors: Department of Obstetrics and Gynecology, Japan Community Health Care Organization, Isahaya General Hospital, Isahaya, Japan.
authors: Shiko
authors: S
authors: Yoshida
authors: Department of Obstetrics and Gynecology, Japan Community Health Care Organization, Isahaya General Hospital, Isahaya, Japan.
authors: Sachiko
authors: S
authors: Morisaki
authors: Department of Obstetrics and Gynecology, Japan Community Health Care Organization, Isahaya General Hospital, Isahaya, Japan.
authors: Ai
authors: A
authors: Fukushima
authors: Department of Obstetrics and Gynecology, Japan Community Health Care Organization, Isahaya General Hospital, Isahaya, Japan.
authors: Takahiro
authors: T
authors: Matsuwaki
authors: Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
authors: Koh-Ichiro
authors: KI
authors: Yoshiura
authors: Departments of Tumor and Diagnostic Pathology, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.
authors: Masahiro
authors: M
authors: Nakashima
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D049109:Cell Proliferation; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005260:Female; D005350:Fibroma / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D010535:Laparoscopy; D008279:Magnetic Resonance Imaging; D008938:Mitosis; D009154:Mutation; D010051:Ovarian Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D011237:Predictive Value of Tests; D012155:Reticulin / Q000032:analysis; D013997:Time Factors; D047368:Tumor Burden; D014463:Ultrasonography
chemical_list: D014408:Biomarkers, Tumor; C421604:FOXL2 protein, human; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors; D012155:Reticulin
keywords: Case report; FOXL2 analysis; Mitotically active cellular fibroma; Preoperative diagnosis; Rapid growth