Hiroko Imamura

Kyushu University, Hukuoka, Fukuoka, Japan

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Publications (4)9.47 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Müllerian mucinous borderline tumors (MMBTs) usually arise from the ovary. The present report is the first case of primary uterine MMBTs associated with adenomyosis. A 51-year-old woman was referred to our hospital for a complex cystic and solid 4×3 cm right adnexal mass. She had a history of a left ovarian endometriotic cyst and had undergone a left oophorectomy 2 yr prior. A laparotomy was performed, and the tumor was found to be originating in the posterior wall of the uterus. She underwent a total abdominal hysterectomy, right salpingo-oophorectomy, and left salpingectomy. Microscopically, the solid portion of the tumor contained papillary proliferations of glands, which were covered by a mucinous epithelium with mild to moderate nuclear atypia, accompanied by stromal infiltration of inflammatory cells. Islands of adenomyosis were also observed around the cyst. These pathologic findings were similar to the features of ovarian MMBT. We diagnosed this tumor as a uterine MMBT, probably arising from adenomyosis.
    International journal of gynecological pathology: official journal of the International Society of Gynecological Pathologists 01/2014; DOI:10.1097/PGP.0b013e318288b364 · 2.07 Impact Factor
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    ABSTRACT: Ovarian transitional cell tumors include Brenner tumors (BTs) and transitional cell carcinoma (TCC; non-BTs) according to the most recent World Health Organization classification. However, it remains a matter of debate whether TCC represents a distinct entity or a morphologic variant of high-grade serous adenocarcinoma (HG-SC). The purpose of this study was to resolve the above question by clarifying the morphologic, immunohistochemical, and molecular features of TCC. We reviewed 488 cases of epithelial ovarian carcinomas and reclassified them on the basis of the most recent World Health Organization classification with the modifications proposed by Köbel and colleagues, and 35 cases of TCC were identified; 25 and 6 TCCs were admixed with HG-SC and endometrioid adenocarcinoma (EC), respectively, and the remaining 4 cases were pure TCC. TCC components were not observed in any clear cell carcinomas or mucinous adenocarcinomas. Only 2 cases of malignant BT were identified. In addition to TCCs, malignant BTs, and related adenocarcinomas, benign and borderline BTs were included in the following immunohistochemical and molecular analyses. Immunohistochemically, pure TCCs, TCCs admixed with HG-SC, and pure HG-SCs were characterized by frequent aberrant p53 expression (diffuse or null pattern) and WT1/ER/PR/IMP2 immunophenotype, whereas BTs, including benign, borderline, and malignant BTs, were characterized by lack of aberrant p53 expression and WT1/ER/PR/IMP2 immunophenotype. In contrast to the BTs, pure ECs and TCCs admixed with EC showed an ER/PR immunophenotype. Nearly all the tumors with a TP53 gene mutation by molecular analysis showed aberrant p53 staining patterns. In conclusion, TCC is not a distinct entity but a poorly differentiated form of serous or EC, as (1) most TCCs coexist with HG-SC (mostly) or EC (occasionally), and (2) the immunophenotype and molecular features are similar to those of HG-SC or EC but different from those of BTs.
    The American journal of surgical pathology 05/2013; DOI:10.1097/PAS.0b013e3182834d41 · 4.59 Impact Factor
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    ABSTRACT: The nature of "piling up" proliferation of clear cells in müllerian mucinous/mixed borderline tumor has not been well characterized. The purpose of this study was to clarify whether or not such clear cells represent concomitant clear cell neoplasms. First, we carefully reviewed hematoxylin and eosin slides taken from 139 ovarian tumors diagnosed as clear cell carcinoma (112 cases) and müllerian mucinous/mixed borderline tumor (27 cases) to clarify (1) the frequency of piling-up clear cells in müllerian mucinous/mixed borderline tumor and (2) the frequency of the coexistence of typical clear cell carcinoma and müllerian mucinous/mixed borderline tumor. Second, we investigated the immunohistochemical expression of estrogen receptor, hepatocyte nuclear factor-1β, and glypican-3 in proliferating clear cells in both tumors. We identified piling-up clear cells in 56% of müllerian mucinous/mixed borderline tumors. Such clear cells lacked the severe nuclear atypia, complex branching, and dense hyalinized cores of typical clear cell carcinoma. We did not find coexistence of typical clear cell carcinoma and müllerian mucinous/mixed borderline tumor in any tumors. Piling-up clear cells and endocervical-like mucinous cells were positive for estrogen receptor but negative for hepatocyte nuclear factor-1β and glypican-3. Most clear cell carcinomas showed a hepatocyte nuclear factor-1β-positive/estrogen receptor-negative immunophenotype, and about half of them were glypican-3 positive. In conclusion, piling-up clear cells in müllerian mucinous/mixed borderline tumor do not represent concomitant clear cell neoplasms because clear cell carcinoma and müllerian mucinous/mixed borderline tumor hardly ever coexist and because such clear cells in both tumors are immunophenotypically distinct.
    Human pathology 03/2012; 43(10):1618-26. DOI:10.1016/j.humpath.2011.11.019 · 2.81 Impact Factor
  • 01/2012; 51(6):435-440. DOI:10.5795/jjscc.51.435