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Dive into the research topics where Kenji Umayahara is active.

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Featured researches published by Kenji Umayahara.


Genes, Chromosomes and Cancer | 2002

Comparative genomic hybridization detects genetic alterations during early stages of cervical cancer progression.

Kenji Umayahara; Fumitaka Numa; Yutaka Suehiro; Aki Sakata; Shugo Nawata; Hidenobu Ogata; Yoshinori Suminami; Masaru Sakamoto; Hiroshi Kato

Invasive cervical carcinoma is thought to arise from cervical intraepithelial neoplasm (CIN). Genetic changes that occur during progression of CIN to cervical carcinoma are poorly understood, although they appear to be directly involved in this process. We used comparative genomic hybridization (CGH) with precise microdissection and degenerate oligonucleotide primed‐polymerase chain reaction (DOP‐PCR) to detect genetic alterations in normal epithelial, CIN, and invasive carcinoma tissues colocalized in tumors from 18 patients with squamous cell carcinoma of the uterine cervix. Gains on chromosome 1 and on 3q and losses on 2q, 3p, 4, 6p, 11q, and 17p were frequent alterations found in CIN and invasive carcinoma lesions. Interestingly, several of these genetic changes were observed in preinvasive carcinoma lesions. The frequency and average number of genetic alterations corresponded directly to the extent to which the cervical carcinoma had progressed. Frequent alterations were found in more than 90% of CIN III lesions. Gains on 3q and losses on 11q were the most prevalent genetic alterations found in association with uterine cervix carcinogenesis. The common regions of alteration were 3q26.1‐q28 and 11q23‐qter. The majority of tumor samples showed variability in genetic alterations across lesion types within a single specimen.


Oncology | 2000

Genetic Aberrations Detected by Comparative Genomic Hybridization in Ovarian Clear Cell Adenocarcinomas

Yutaka Suehiro; Masaru Sakamoto; Kenji Umayahara; Iwabuchi H; Hiroko Sakamoto; Naotake Tanaka; Nobuhiro Takeshima; Kazuhiro Yamauchi; Katsuhiko Hasumi; Tsukasa Akiya; Sakunaga H; Tetsuya Muroya; Fumitaka Numa; Hiroshi Kato; Yoshio Tenjin; Tadashi Sugishita

Genetic abnormalities were detected by comparative genomic hybridization (CGH) in 12 ovarian clear cell adenocarcinomas. DNA sequence copy number abnormalities (CNAs) occurring in more than 20% of the cancers included increased copy numbers of 8q11-q13, 8q21-q22, 8q23, 8q24-qter, 17q25-qter, 20q13-qter and 21q22-qter and reduced copy numbers of 19p. Increases in copy numbers of 8q11-q13, 8q21-q22, 8q23 and 8q24-qter occurred more frequently in disease-free patients than in recurrent/non-surviving patients (p < 0.05). However, increases in copy numbers of 17q25-qter and 20q13-qter occurred more frequently in recurrent/non-surviving patients than in disease-free patients (p < 0.05). Furthermore, increases in copy numbers of 17q25-qter and 20q13-qter occurred together (p < 0.05). Additionally, there were negative correlations between increases in copy numbers of 8q21-q22 and 17q25-qter, and between 8q21-q22 and 20q13-qter (p < 0.05). It appears that ovarian clear cell adenocarcinomas can be classified into two subtypes, one being cancer with an increase in copy numbers of 8q and the other being cancer with increases in copy numbers of 17q25-qter and 20q13-qter.


Genes, Chromosomes and Cancer | 2000

Genetic aberrations detected by comparative genomic hybridization predict outcome in patients with endometrioid carcinoma.

Yutaka Suehiro; Kenji Umayahara; Hidenobu Ogata; Fumitaka Numa; Yoshimi Yamashita; Atsunori Oga; Hitoshi Morioka; Takehisa Ito; Hiroshi Kato

Endometrial cancer progression is determined by a complex pattern of multiple genetic aberrations, but how these aberrations affect prognosis is unknown. In this study, we undertook a genome‐wide screening to detect genetic changes by comparative genomic hybridization (CGH) in 51 tumors from patients with primary endometrioid carcinoma of the uterine corpus. The observed genetic changes were subsequently correlated with the progression of the disease and the clinical outcome in each case. The average number of genetic aberrations (copy number gains and losses) was significantly greater in non‐surviving patients than in disease‐free patients (12.6 vs. 2.7, P < 0.0001). According to multivariate analysis, lymph node metastasis (P = 0.015), cervical involvement (P = 0.007) and one or more copy number losses at 9q32–q34, 11q23, or Xq12–q24 (P = 0.023) were significantly predictive of death from the disease. Interestingly, lymph node metastasis was significantly associated with copy number gains at 8q22–q23 and 8q24–qter (P = 0.003 and P = 0.025, respectively). Moreover, cervical involvement was also correlated significantly not only with gains of 8q22–q23 and 8q24–qter but also with loss of 11q23 (P = 0.04, 0.0003, and P = 0.009, respectively). These results suggest that analysis of genetic changes may help predict clinical outcome and the presence of metastatic disease as well as assist in therapeutic decision making for patients with endometrioid carcinoma. Genes Chromosomes Cancer 29:75–82, 2000.


Gynecologic Oncology | 2012

Phase II study of concurrent chemoradiotherapy with high-dose-rate intracavitary brachytherapy in patients with locally advanced uterine cervical cancer: Efficacy and toxicity of a low cumulative radiation dose schedule ☆

Takafumi Toita; Ryo Kitagawa; Tetsutaro Hamano; Kenji Umayahara; Yasuyuki Hirashima; Yoichi Aoki; Masahiko Oguchi; Mikio Mikami; Ken Takizawa

OBJECTIVE A multicenter phase II trial was conducted to assess the efficacy and toxicity of concurrent chemoradiotherapy (CCRT) with high-dose-rate intracavitary brachytherapy (HDR-ICBT) using a low cumulative prescribed dose schedule in patients with locally advanced uterine cervical cancer. METHODS The Japanese Gynecologic Oncology Group (JGOG) study JGOG1066 enrolled patients with FIGO stages III-IVA uterine cervical cancer who had no para-aortic lymphadenopathy (>10 mm) assessed by CT. Patients received definitive radiotherapy (RT) consisting of external beam whole pelvic RT and HDR-ICBT. The cumulative linear quadratic equivalent dose (EQD2) was 62-65 Gy prescribed at point A. Cisplatin 40 mg/m(2) weekly was administered concurrently with RT for 5 courses. RESULTS Of the 72 patients registered, 71 were eligible. With a median follow-up of 28 months, the 2-year progression-free survival rate and pelvic disease progression-free rate were 66% (95% CI, 54% to 76%) and 73% (95% CI, 61% to 82%), respectively. Progression-free survival decreased significantly with increased central tumor size (P=0.036). The 2-year cumulative late complication rates were 24% for all grades, 9% for grade 1, 12% for grade 2, 3% for grade 3, and 0 for grades 4/5. CONCLUSIONS The JGOG1066 demonstrated that CCRT using HDR-ICBT with a low cumulative RT dose schedule achieved comparable outcome as those achieved with global dose schedules (EQD2=85 Gy) with a lower incidence of late toxicity for locally advanced uterine cervical cancer in a Japanese population.


International Journal of Gynecological Cancer | 2011

Parametrial involvement in FIGO stage IB1 cervical carcinoma diagnostic impact of tumor diameter in preoperative magnetic resonance imaging.

Teruyo Kamimori; Kimihiko Sakamoto; Kiyoshi Fujiwara; Kenji Umayahara; Yuko Sugiyama; Kuniko Utsugi; Nobuhiro Takeshima; Hiroko Tanaka; Naoya Gomi; Ken Takizawa

Background: In the surgical treatment for early-stage cervical carcinoma, it is important to identify preoperatively a low-risk group of patients as candidates for less radical surgery to avoid the morbidity associated with radical hysterectomy. The aim of this study was to evaluate the correlation between tumor diameter measured preoperatively using magnetic resonance imaging (MRI) and pathological prognostic factors in International Federation of Gynecology and Obstetrics (FIGO) stage IB1 cervical carcinoma. Methods: A total of 125 patients with FIGO stage IB1 cervical cancer were included in this study. Clinical records, pathology reports, and MRI findings were retrospectively reviewed. Results: Histological diagnosis was squamous cell carcinoma in 57 patients and nonsquamous cell carcinoma in 68 patients. All patients underwent preoperative evaluation by MRI within a median period of 13.5 days before surgery. The tumor diameter measured by MRI ranged from zero (no tumor detected) to 42 mm, with a median of 23 mm. Pathological prognostic factors included parametrial involvement, lymph node metastasis, deep stromal invasion, and lymphovascular space invasion. All these factors were found less frequently in patients with a smaller tumor diameter. Most notably, parametrial involvement was seen in none of the patients with tumors 20 mm or less and was detected only in patients with tumors greater than 20 mm (P = 0.01). Conclusions: In the FIGO stage IB1 cervical carcinoma, the tumor diameter measured preoperatively by MRI correlates well with other pathological prognostic factors, especially with parametrial involvement. This finding suggests that the tumor diameter measured in preoperative MRI may serve as a strong predictor of parametrial involvement in FIGO stage IB1 cervical carcinoma, which can be used to select a candidate population for less radical surgery without the need for a cone biopsy before hysterectomy.


Gynecologic Oncology | 2010

Neoadjuvant chemotherapy followed by radical hysterectomy plus postoperative chemotherapy but no radiotherapy for Stage IB2-IIB cervical cancer—Irinotecan and platinum chemotherapy

Maki Matsumura; Nobuhiro Takeshima; Tsuyoshi Ota; Kohei Omatsu; Kimihiko Sakamoto; Yasutaka Kawamata; Kenji Umayahara; Hiroko Tanaka; Futoshi Akiyama; Ken Takizawa

OBJECTIVE To evaluate the effectiveness of neoadjuvant chemotherapy (NAC) followed by radical hysterectomy plus postoperative chemotherapy but no radiotherapy for stage IB2-IIB cervical cancer. METHODS Forty-six consecutive patients with stage IB2-IIB cervical cancer were treated with NAC followed by radical hysterectomy plus postoperative chemotherapy. Median (range) body mass index (BMI) of the patients was 20.2 (16.2-26.4). Regimens for NAC and postoperative chemotherapy were irinotecan and cisplatin (CPT-11/CDDP) or CPT-11 and nedaplatin (CPT-11/NDP). A total of six cycles of NAC and postoperative chemotherapy were prescribed. No use of radiotherapy was scheduled, except in the case of a recurrence. RESULTS With a median follow-up period for survivors of 38.8 months (range 24-54 months), the 2- and 3-year progression-free survival rates were 91.2% and 86.1%, respectively. Overall response rate of NAC was 80.4%. Recurrence was observed in seven patients. In the absence of radiotherapy, pelvic recurrence was observed in only three patients; another two had para-aortic lymph nodes and the remaining two distant metastases. Toxicities due to chemotherapy were generally tolerable. Postoperative complications included urinary fistula (four patients, 8.7%) and bowel obstruction (two patients, 4.3%), all of which required surgical intervention. CONCLUSION The results indicate that NAC followed by surgery plus postoperative chemotherapy but no radiotherapy offers a viable option in the treatment of stage IB2-IIB cervical cancer. Although a relatively large incidence of postsurgical complications was observed among low-BMI patients, this treatment offers the advantage of minimizing radiation-induced morbidity, allowing radiotherapy to be reserved for the possible event of pelvic recurrence.


Japanese Journal of Cancer Research | 2000

Evaluation of the Reliability of Chromosomal Imbalances Detected by Combined Use of Universal DNA Amplification and Comparative Genomic Hybridization

Tomohiko Harada; Kei Shiraishi; Noriyoshi Kusano; Kenji Umayahara; Satoshi Kondoh; Kiwamu Okita

Comparative genomic hybridization (CGH) analysis of microscopic tumor samples is allowed by universal DNA amplification using degenerate oligonucleotide primed‐PCR (DOP‐PCR). To evaluate the reliablity of DOP‐PCR CGH, we performed DOP‐PCR CGH and standard CGH in parallel using DNAs extracted from 10 malignant tumors of the hepatobiliary tract and pancreas. Similar results were obtained by both methods with a few exceptions, indicating that DOP‐PCR CGH provides cytogenetic information equivalent to that obtained from standard CGH. We also investigated the sensitivity of DOP‐PCR CGH using sequential dilutions of DNA from microdissected tumor cells. DOP‐PCR using 100 to 800 pg of template DNA yielded successful CGH results. However, less than 50 pg of template DNA was not suitable because of the small amount of generated DNA. These findings suggest that DOP‐PCR CGH is applicable for CGH analysis of tiny specimens which are too small for standard CGH. Accordingly, DOP‐PCR CGH analysis may become a useful method in clinical laboratory examination.


Tumor Biology | 2001

Serum Anti-p53 Antibodies in Uterine and Ovarian Cancer: Association with DNA Sequence Copy Number Abnormalities

Fumitaka Numa; Kenji Umayahara; Yutaka Suehiro; Hiroshi Hirakawa; Shugo Nawata; Yoshinori Suminami; A. Oga; Takehisa Ito; Hiroshi Kato

The aim of the present study was to evaluate the clinical significance of the serum anti-p53 antibody in patients with uterine and ovarian cancer. Some of the ovarian patients were also evaluated for overexpression of p53 by immunohistochemistry and for cytogenetic alterations by comparative genomic hybridization (CGH). Serum anti-p53 antibodies were determined by an enzyme immunoassay kit. The antibody was detected in 8/30 (27%) of ovarian cancers, in 12/86 (14%) cancers of the uterine cervix, in 5/41 (12%) cancers of the uterine body, and 0/9 (0%) healthy women. The overall survival rate in patients with ovarian cancer was significantly worse in patients with anti-p53 antibody positivity than that in patients with anti-p53-antibody-negative cancers using the log rank test (p = 0.017). There was a significant correlation between the presence of anti-p53 antibody and tissue overexpression of p53 in ovarian cancers. CGH analysis showed that the aberrations in DNA sequence copy number in ovarian cancers were significantly increased in anti-p53-antibody-positive cases compared to antip53-antibody-negative cases including increased copy number on 20q and reduced copy number on 5q and 13q. Although the exact relationship between the presence of serum anti-p53 antibody (specific humoral response) and cytogenetic alterations is still unknown, these findings suggest that the measurement of serum anti-p53 antibody may be useful for the assessment of genetic instability and tumor biological aggressiveness.


International Journal of Gynecological Cancer | 2012

Feasibility and acute toxicity of Concurrent Chemoradiotherapy (CCRT) with high-dose rate intracavitary brachytherapy (HDR-ICBT) and 40-mg/m2 weekly cisplatin for Japanese patients with cervical cancer: results of a Multi-Institutional Phase 2 Study (JGOG1066).

Takafumi Toita; Ryo Kitagawa; Tetsutaro Hamano; Kenji Umayahara; Yasuyuki Hirashima; Yoichi Aoki; Masahiko Oguchi; Mikio Mikami; Ken Takizawa

ObjectiveTo assess the feasibility and acute toxicity of concurrent chemoradiotherapy (CCRT) with high–dose rate intracavitary brachytherapy (HDR-ICBT) and standard dose delivery of cisplatin for Japanese patients with cervical cancer. Materials and MethodsThe phase 2 study included Japanese patients with International Federation of Gynecology and Obstetrics stage III to IVA uterine cervical cancer who had no para-aortic lymphadenopathy (>10 mm) assessed by computed tomography. Patients were 20 to 70 years of age and had Eastern Cooperative Oncology Group performance status of 0 to 1. The radiotherapy protocol consisted of whole-pelvis external beam radiotherapy and HDR-ICBT. The cumulative linear quadratic equivalent dose (EQD2) was 62 to 65 Gy prescribed at point A. Cisplatin was administered weekly at a dose of 40 mg/m2 for 5 courses. ResultsBetween March 2008 and January 2009, 72 patients from 25 institutions were enrolled, and 71 patients were eligible and evaluable for compliance and severe toxicity. The median age of the patients was 57 years (range, 32–70 years). Sixty-five patients (92%) received the planned 5 courses of chemotherapy. Four patients had cisplatin dose reduction according to the protocol. Radiotherapy was completed per protocol in 68 patients (96%). Median overall treatment time was 50 days (range, 37–66 days). The following grade 3 or 4 acute adverse events were observed: neutropenia in 31 patients (44%), anemia in 10 patients (14%), diarrhea in 4 patients (6%), and anorexia in 3 patients (4%). ConclusionsConcurrent chemoradiotherapy with HDR-ICBT and standard weekly delivery of cisplatin was feasible with acceptable toxicity in Japanese patients with cervical cancer.Objective To assess the feasibility and acute toxicity of concurrent chemoradiotherapy (CCRT) with high–dose rate intracavitary brachytherapy (HDR-ICBT) and standard dose delivery of cisplatin for Japanese patients with cervical cancer. Materials and Methods The phase 2 study included Japanese patients with International Federation of Gynecology and Obstetrics stage III to IVA uterine cervical cancer who had no para-aortic lymphadenopathy (>10 mm) assessed by computed tomography. Patients were 20 to 70 years of age and had Eastern Cooperative Oncology Group performance status of 0 to 1. The radiotherapy protocol consisted of whole-pelvis external beam radiotherapy and HDR-ICBT. The cumulative linear quadratic equivalent dose (EQD2) was 62 to 65 Gy prescribed at point A. Cisplatin was administered weekly at a dose of 40 mg/m2 for 5 courses. Results Between March 2008 and January 2009, 72 patients from 25 institutions were enrolled, and 71 patients were eligible and evaluable for compliance and severe toxicity. The median age of the patients was 57 years (range, 32–70 years). Sixty-five patients (92%) received the planned 5 courses of chemotherapy. Four patients had cisplatin dose reduction according to the protocol. Radiotherapy was completed per protocol in 68 patients (96%). Median overall treatment time was 50 days (range, 37–66 days). The following grade 3 or 4 acute adverse events were observed: neutropenia in 31 patients (44%), anemia in 10 patients (14%), diarrhea in 4 patients (6%), and anorexia in 3 patients (4%). Conclusions Concurrent chemoradiotherapy with HDR-ICBT and standard weekly delivery of cisplatin was feasible with acceptable toxicity in Japanese patients with cervical cancer.


International Journal of Gynecological Cancer | 2009

Phase I study of concurrent chemoradiotherapy with weekly cisplatin and paclitaxel chemotherapy for locally advanced cervical carcinoma in Japanese women.

Kenji Umayahara; Nobuhiro Takeshima; Takayuki Nose; Kiyoshi Fujiwara; Yuko Sugiyama; Kuniko Utsugi; Takashi Yamashita; Ken Takizawa

The purpose of this study was to evaluate the use of concurrent chemoradiotherapy involving weekly administration of cisplatin and paclitaxel for the treatment of locally advanced cervical carcinoma in Japanese women. Twenty Japanese patients were registered for this phase I study. Radiation therapy was performed using external irradiation and high-dose rate intracavitary irradiation of the pelvis. Chemotherapy was performed once a week until termination of the radiation therapy. The dose of cisplatin was decided as 30 mg/m2, and the initial dose of paclitaxel was set as 30 mg/m2, with a planned incremental increase of 10 mg/m2 up to 70 mg/m2. When 3 to 6 patients were registered at each dose level and dose-limiting toxicity (DLT) was noted in more than 3 patients, the dose level was assumed to be the maximum tolerated dose. Among the 20 patients, 1 patient experienced DLT during 2 courses because of dehydration and arrhythmia. In another patient, chemotherapy was discontinued after 4 courses because of a hypersensitivity reaction to paclitaxel at dose level 3. No patient experienced DLT resulting from hematologic toxicities. All patients underwent radiation therapy according to schedule without any discontinuations. A complete response was obtained in 16 patients. Based on the results obtained from this study, weekly administration of 30 mg/m2 cisplatin and 50 mg/m2 paclitaxel with concurrent chemoradiotherapy can be considered a tolerable and safe dose for the treatment of locally advanced cervical carcinoma in Japanese women.

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Nobuhiro Takeshima

Japanese Foundation for Cancer Research

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Ken Takizawa

Japanese Foundation for Cancer Research

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Kohei Omatsu

Japanese Foundation for Cancer Research

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Maki Matoda

Japanese Foundation for Cancer Research

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Kuniko Utsugi

Japanese Foundation for Cancer Research

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