Biomedical subjects

Masato Nishida

Publications and source records attributed to Masato Nishida.

8 recordsLinked to original sources

PubMed2004

Smooth muscle tumors of uncertain malignant potential and leiomyosarcomas of the uterus: MR findings.

PURPOSE: To study the MR characteristics of nonbenign uterine smooth muscle tumors. MATERIALS AND METHODS: Nine patients with pathologically proven leiomyosarcomas, and three patients with smooth muscle tumors of uncertain malignant potential (SMTUMP) were included in this study. Twelve cases of benign uterine leiomyomas and variants, in which gynecologists suspected leiomyosarcomas, were also analyzed. In each case we studied the size, location, signal intensity, and contrast enhancement of the tumors. RESULTS: Nine of the 12 nonbenign characters had more than 50% of high-intensity areas on T2-weighted images (T2WI), and some hyperintense foci on T1-weighted images (T1WI). In the contrast study, nine of 12 nonbenign characters had well-demarcated unenhanced areas. On the other hand, only two of 12 benign characters showed such a signal intensity pattern, and none of them had a pocket-like unenhanced area. CONCLUSION: Although there were some exceptions, more than 50% of high signal on T2WI, and the presence of any small high-signal areas on T1WI with unenhanced pockets were considered MR-suggestive for SMTUMPs and leiomyosarcomas.

Adult↗

PubMed2004

Complete response to irinotecan hydrochloride and nedaplatin in a patient with advanced ovarian clear cell carcinoma.

A 55-year-old multiparous woman was diagnosed with stage IIIc ovarian clear cell carcinoma. Three years after the first surgery and adjuvant chemotherapy with irinotecan hydrochloride and mitomycin C, she developed common iliac lymph node recurrence. Two cycles of chemotherapy with irinotecan hydrochloride and nedaplatin led to a complete response. Surgical resection revealed pathological complete response. The chemosensitivity of ovarian clear cell carcinoma has been reported to be very poor. No standard chemotherapeutic regimens for this carcinoma have been established. The present study is the first report of a pathological complete response in a patient with advanced ovarian clear cell carcinoma. Future studies are needed to confirm the efficacy of this regimen for this carcinoma.

Adenocarcinoma, Clear Cell↗

PubMed2004

Phase II study of irinotecan combined with mitomycin-C for advanced or recurrent squamous cell carcinoma of the uterine cervix: the JGOG study.

OBJECTIVES: The efficacy and toxicity of combined therapy with irinotecan (CPT-11) plus mitomycin-C (MMC) were evaluated in patients with advanced or recurrent squamous cell carcinoma (SCC) of the uterine cervix. METHODS: CPT-11 (100 mg/m(2)) was administered on days 1, 8, and 15 by intravenous (iv) infusion over 90 min, while MMC (10 mg/m(2) iv) was given on day 1. This regimen was repeated every 28 days and at least two courses were given. RESULTS: Among 51 eligible patients (median age: 52 years; range: 25-72 years), 2 showed complete response (CR) and 24 showed PR, for an overall response rate (ORR) of 51.0% (95% confidence interval: 36.6-65.3%). In patients without prior chemotherapy, the ORR was 54.8% (38.7-70.2%). Twenty-five patients (Ib2:3, IIb:17, and IIIb:5) received this regimen as neoadjuvant chemotherapy and their ORR was 76% (54.9-90.6%). Twenty-two patients were able to undergo radical surgery after NAC. The major toxicity was neutropenia, which was grade 3-4 in 59% of the patients. Grade 3-4 thrombocytopenia and anemia were also seen in 26% of the patients each. The most common nonhematologic toxicity was diarrhea (grade 3-4 in 12%). CONCLUSION: CPT-11 combined with MMC can be effective against advanced or recurrent SCC of the uterine cervix.

Adult↗

PubMed2003

A thickened or indistinct junctional zone on T2-weighted MR images in patients with endometrial carcinoma: pathologic consideration based on microcirculation.

Thickened or indistinct junctional zone (JZ) is a problematic finding in staging endometrial carcinoma. We studied the incidence, pathological cause of this condition correlated to microcirculation, and the utility of dynamic contrast MRI for differential diagnosis. T2-weighted images were analyzed in 119 cases with endometrial carcinoma. The enhancement of the JZ during the dynamic contrast MRI, histopathological causes, and the density of arterioles in the JZ were retrospectively analyzed in cases with thickened or indistinct JZ. The MRI histopathological correlation of all 31 patients with a thickened or indistinct JZ were analyzed, in which it was corresponded to myometrial cancer invasion only in 22%. The sensitivity of a poor early enhancement pattern on dynamic study for detecting myometrial invasion was 71.4%, the specificity was 100%, and the overall accuracy was 92.5%. Although only weak relationship between the contrast enhancement and the arteriole density was revealed, the arteriole density within the JZ with cancer invasion was significantly decreased. Poor enhancement of JZ in early dynamic phase was correlated with the decreased density of arterioles within the myometrium which was invaded by endometrial carcinoma. Dynamic contrast study should be performed in staging endometrial carcinoma especially when JZ was thickened or indistinct.

Endometrial Neoplasms↗

PubMed2002

Assessment of cervical cancer radioresponse by serum squamous cell carcinoma antigen and magnetic resonance imaging.

OBJECTIVE: To investigate the possibility of objective clinical assessment of the radioresponse of cervical cancer via determination of serum squamous cell carcinoma antigen levels and magnetic resonance imaging (MRI)-based estimation of tumor shrinkage. METHODS: The cases of 60 patients undergoing definitive radiotherapy for cervical squamous cell carcinoma (stage I-II: n = 20; stage III-IV: n = 40) were reviewed. Measurements of serum squamous cell carcinoma antigen levels (n = 60), estimated tumor volume on preradiotherapy MRIs (n = 60), and evaluated tumor shrinkage on postradiotherapy MRIs available (n = 30) were taken. The relation between postradiotherapy squamous cell carcinoma antigen level 2 months after the start of radiotherapy and disease recurrence was investigated. Regression analysis of tumor volume measured on MRIs was used to estimate the extent of tumor shrinkage 2 months after the start of radiotherapy. RESULTS: Preradiotherapy squamous cell carcinoma antigen levels correlated significantly with preradiotherapy tumor volumes. Recurrence was identified in 27 patients as distant (n = 19), distant and local (n = 1), local (n = 5), or regional (n = 2). Of 51 patients with elevated preradiotherapy squamous cell carcinoma antigen levels, 33 achieved normalized levels after radiotherapy. Squamous cell carcinoma antigen normalization was associated with a higher recurrence-free survival rate at 2 years (74.3%) than that associated with nonnormalization of squamous cell carcinoma antigen (5.6%, P <.001). The extent of shrinkage ranged from 61% to 100%, and there was no local recurrence. CONCLUSION: Postradiotherapy squamous cell carcinoma antigen status is a useful indicator of clinical outcome, particularly about tumor recurrence. It is not, however, useful for assessing response to radiotherapy. Magnetic resonance imaging is useful for obtaining an objective assessment of radioresponse.

Antigens, Neoplasm↗

PubMed2002

The Ishikawa cells from birth to the present.

More than 20 years have passed since the Ishikawa cell line, a well-differentiated human endometrial adenocarcinoma cell line, was established. Because this cell line bears estrogen and progesterone receptors, the cells have been used in numerous basic research areas such as reproductive biology and molecular science, and has been distributed to more than a hundred institutes. However, even the Ishikawa cells, after long-term culture, tend to transform into undifferentiated cells. In addition, it has been reported that estrogen and progesterone receptors disappeared from the cells that I distributed. I therefore attempted to establish well-differentiated cells from the parent Ishikawa cells and to produce a new and good quality supply of this cell line. I believe that it is very important for the investigator who established a cell line to be responsible for maintaining the quality of the cells. That is why I have not deposited this cell line in any cell bank. I would like to take this opportunity to report the history of Ishikawa cells from establishment to the present.

Adenocarcinoma↗

PubMedDate not supplied

Ovarian tumor with functioning stroma.

The authors reported two cases with ovarian tumors with functioning stroma. One was an ovarian carcinoid with testosterone-producing stroma and another was an ovarian mucinous cystadenoma with elevated serum level of estrogen. They appeared as multilocular cystic masses with varying signal on MR. This imaging feature was mimicking both those of Sertoli-Leydig tumors with heterologous elements and granulosa cell tumors, which are well known as functioning tumors. It had been reported in pathological literatures that any type of ovarian tumors can show hormonal activity due to functional stroma, although, it is the first report in the radiological literatures.

Aged↗

PubMedDate not supplied

MR imaging of the uterine cervix: imaging-pathologic correlation.

Magnetic resonance (MR) imaging is useful not only for preoperative staging of gynecologic malignancies but also for prediction of the histopathologic features of a variety of intrapelvic tumors. Familiarity with the specific imaging findings that have been reported for the uterine cervix is a goal of radiologists. The typical MR imaging findings of uterine cervical lesions correspond to the histopathologic features. These lesions can be categorized as epithelial neoplasms, nonepithelial neoplasms, and nonneoplastic diseases. Cervical carcinoma accounts for most cases of malignant lesions and is staged by using the classification system established by the International Federation of Gynecology and Obstetrics. MR imaging allows differentiation between endophytic and exophytic growth and between normal and abnormal findings after hysterectomy and irradiation. Other epithelial neoplasms of the uterine cervix include adenoma malignum, which is a special type of cervical adenocarcinoma, as well as carcinoid tumor and malignant melanoma. Nonepithelial neoplasms of the uterine cervix include malignant lymphoma and leiomyoma. Nonneoplastic diseases of the uterine cervix include cervical pregnancy, cervicitis, nabothian cysts, polyps, and endometriosis.

Cervix Uteri↗