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Scandinavian Journal of Urology and Nephrology | 2001

Moderate dose diethylstilbestrol diphosphate therapy in hormone refractory prostate cancer.

Yutaka Takezawa; Seiji Nakata; Mikio Kobayashi; Nozomu Kosaku; Yoshitatsu Fukabori; Hidetoshi Yamanaka

Objective: To examine the efficacy and toxicity of a moderate dose (250 mg/day) of diethylstilbestrol diphosphate (DES-DP) intravenously administered to patients with hormone refractory prostate cancer (HRPC) as well as the influence of this agent on the endocrine system. Patients and methods: Sixteen patients with HRPC were treated with a daily intravenous injection of 250 mg of DES-DP for 28 days. Eastern Cooperation Oncology Group (ECOG) performance status and pain score were used for subjective evaluation and PSA was used for objective evaluation. Testosterone, free testosterone, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) were used for hormonal parameters. Results:OBJECTIVE To examine the efficacy and toxicity of a moderate dose (250 mg/day) of diethylstilbestrol diphosphate (DES-DP) intravenously administered to patients with hormone refractory prostate cancer (HRPC) as well as the influence of this agent on the endocrine system. PATIENTS AND METHODS Sixteen patients with HRPC were treated with a daily intravenous injection of 250 mg of DES-DP for 28 days. Eastern Cooperation Oncology Group (ECOG) performance status and pain score were used for subjective evaluation and PSA was used for objective evaluation. Testosterone, free testosterone, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) were used for hormonal parameters. RESULTS Fourteen patients were eligible. The mean patient age was 75.2 years. With respect to the ECOG pain score, 5 patients scored 1 or higher, in 4 patients, the pain completely disappeared, and in 1 patient, the pain score improved from 4 to 1. The PSA level decreased significantly from 528 +/- 556 ng/ml (mean +/- SD) to 154 +/- 197 ng/ml. The DHEA level was not changed during DES-DP administration. The DHEA-S level decreased significantly from 882 +/- 430 ng/ml to 480 +/- 236 ng/ml. Testosterone and free testosterone were in the castration level before and during the treatment. Toxicity was minimal. None of the patients developed cardiovascular disorder. CONCLUSION A moderate dose (250 mg/day) of DES-DP decreased PSA levels and relieved pain without causing serious toxicity in patients with HRPC. It is suggested that the mechanism of the DES-DP effect on the decrease in PSA and pain relief involves a decrease in DHEA-S.


Pathology International | 1992

Inhibitory Influence of a New Steroidal Anti‐androgen, TZP‐4238, on Prostatic Hyperplasia in the Beagle Dog

Masanori Murakoshi; Rie Inada; Masashi Tagawa; Masao Makino; Minoru Suzuki; Mamoru Mieda; Seijiroh Honma; Yutaka Takezawa; Hidetoshi Yamanaka

The effect of a synthetic steroidal anti‐androgen, TZP‐4238, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Old male beagle dogs (5–9 years old) were divided into three experimental groups. Group 1 consisted of BPH controls. Groups 2 and 3 received TZP‐4238 0.1 mg/kg/day and chlormadinone acetate (CMA) 0.3 mg/kg/day P.o., respectively, for 5 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In contrast, TZP‐4238 (Group 2) or CMA (Group 3) produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that TZP‐4238 or CMA medication for 5 months exerted no effect on the testes and the pituitary luteinizing hormone (LH) cells. Therefore, it is suggested that TZP 4238 (0.1 mg/kg) or CMA (0.3 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes and pituitary LH cells. However, slightly decreased serum testosterone levels were found in TZP 4238 treated animals, due apparently to a direct and/or indirect effect on the testes. Thus, it is suggested that a marginal antigonadotrophic effect cannot be excluded. It is concluded that TZP‐4238 is a potent anti‐androgen for the treatment of spontaneous canine BPH, without any negative influence on the function of the testes and the pituitary LH cells. Acta Pathol Jpn 42: 151–157, 1992.


Journal of Radiation Research | 2012

Risk factors for rectal bleeding associated with I-125 brachytherapy for prostate cancer.

Kosaku Harada; Hitoshi Ishikawa; Yoshitaka Saito; Soken Nakamoto; Hidemasa Kawamura; Masaru Wakatsuki; Toru Etsunaga; Yutaka Takezawa; Mikio Kobayashi; Takashi Nakano

The purpose of this study was to determine the risk factors for rectal bleeding after prostate brachytherapy. Between April 2005 and September 2009, 89 patients with T1c-2cN0M0 prostate cancer were treated with permanent I-125 seed implantation alone. The prostate prescription dose was 145 Gy, and the grade of rectal bleeding was scored according to the Common Terminology Criteria for Adverse Events version 4.0. Post-treatment planning was performed with fusion images of computerized tomography and magnetic resonance imaging 4–5 weeks after brachytherapy. Patient characteristics and dosimetric parameters were evaluated to determine risk factors for bleeding. The calculated parameters included the rectal volume in cubic centimeters that received >50–200% of the prescribed dose (RV50–200) and the minimal doses received by 1–30% of the rectal volume (RD1–30). The median follow-up time was 42 months (ranging 18–73 months). Grade 1 rectal bleeding occurred in 24 (27.0%) patients, but no Grade 2 or severe bleeding was observed. Usage of anticoagulants had a significant correlation with the occurrence of bleeding (P = 0.007). The RV100–150 and RD1–10 were significantly higher in patients with rectal bleeding than in those without bleeding. The RV100 was identified as a possible threshold value; the 3-year rectal bleeding rate in patients with an RV100 > 1.0 cm3 was 36%, whereas that with an RV100 ≤ 1.0 cm3 was 14% (P < 0.05). Although no Grade 2 morbidity developed in this study, the RV100 should be kept below 1.0 cm3, especially in additional dose-escalated brachytherapy.


International Journal of Urology | 1996

Acute Renal Failure in a Patient with Chronic Glomerulonephritis after the Administration of Luteinizing Hormone‐Releasing Hormone Analogue Given for Rectal Obstruction Due to Prostate Cancer

Yutaka Takezawa; Katsuya Nakano; Nobuaki Ohtake; Hidetoshi Yamanaka

We report a case in which rectal obstruction due to prostate cancer was exacerbated due to an ileus after the administration of luteinizing hormone‐releasing hormone analogue. The obstruction led to copious vomiting, dehydration and renal failure which necessitated hemodialysis. Improvement of the patient was noted four weeks after the start of hormonal treatment with a decrease in rectal obstruction concomitant with decreases in testosterone and prostate specific antigen levels.


Clinical and Experimental Nephrology | 2012

Matrix metalloproteinase levels in peritoneal effluents were increased in a patient with appendicitis undergoing continuous ambulatory peritoneal dialysis

Yutaka Takezawa; Yoshitaka Saitou; Tatsuya Uchida; Ichiro Hirahara; Eiji Kusano; Mikio Kobayashi

A differential diagnosis of common bacterial peritonitis and appendicitis is difficult in continuous ambulatory peritoneal dialysis (CAPD) patients, and thus the definite diagnosis of appendicitis is often delayed. In this case, a 60-year-old man undergoing CAPD was at first diagnosed with bacterial peritonitis but not appendicitis, and antibiotics were administered. The number of leukocytes in the peritoneal effluent decreased mildly, but the level of C-reactive protein continued to be high and the pain aggravated. When the catheter was removed, suppurative appendicitis was confirmed for the first time. Levels of matrix metalloproteinase (MMP)-2 and -9 in peritoneal effluents were markedly high. Appendicitis should be diagnosed as early as possible because MMPs directly injure the peritoneum via degradation of extracellular matrix proteins. Future studies in a greater numbers of cases of appendicitis are required.


Histochemistry and Cell Biology | 1997

Carcinogenesis in accessory sex organs of rats induced by 3,2′-dimethyl-4-aminobiphenyl: response to androgen deprivation

Yoshimi Tamura; Y. Ono; T. Suzuki; K. Suzuki; Yutaka Takezawa; Tooru Mashimo; Yoshitatsu Fukabori; Hisako Yuasa; Kyoichi Imai; Hidetoshi Yamanaka

Abstract It is generally accepted that early human prostate cancers reveal higher androgen dependency than do advanced ones. In the present study, we examined whether the animal model of prostate cancer has already lost androgen dependency at the early stages of carcinogenesis. At experimental week 46, androgen deprivation was induced in rats and the incidences of atypical hyperplasia and cancer were examined in the ventral, dorsolateral prostate, coagulating glands, and seminal vesicles. Androgen deprivation significantly lowered the incidence of atypical hyperplasia in all four organs. As for the incidence of cancer, no significant differences were observed in the coagulating glands and seminal vesicles. Regarding atypical hyperplasia, androgen deprivation significantly decreased the proliferative cell nuclear antigen labeling index in the coagulating gland and seminal vesicles. The presence of cancer was also decreased in the coagulating gland but not in the seminal vesicles. With control group specimens, more intense staining of androgen receptor was observed in atypical hyperplasias than in cancers. Compared with the atypical hyperplasias, the cancers revealed low androgen dependency at the early stages of carcinogenesis. The cancers in the seminal vesicles also revealed higher androgen independency than did those in the coagulating gland.


The Journal of Urology | 2004

1768: Prognostic Significance of Plasma Placental Growth Factor Levels in Renal Cell Cancer: An Association with Clinical Characteristics and Vascular Endothelial Growth Factor Levels

Kazuhisa Matsumoto; Kazuhiro Suzuki; Hidekazu Koike; Keigo Okamura; Kiyotaka Tsuchiya; Tatsuya Uchida; Yutaka Takezawa; Yoshitatsu Fukabori; Mikio Kobayashi; Hidetoshi Yamanaka

BACKGROUND Angiogenesis plays important roles in pathogenesis in human cancer. We assessed the relationship between clinical features of renal cell cancer (RCC) and PlGF levels in relation to VEGF. MATERIALS AND METHODS Plasma PlGF and VEGF levels were measured in patients with renal cell cancer. The levels of these angiogenetic factors were analyzed in relation to clinical parameters. RESULTS PlGF and VEGF levels in patients with RCC were significantly higher than those in non-cancer controls. PlGF levels were significantly associated with histological grade and total tumor vascularity (TTV), and VEGF levels were significantly associated with T, M stage, histological grade, venous invasion and TTV. Multivariate analysis showed plasma PlGF was an independent prognostic factor. CONCLUSION These findings suggested that plasma PlGF levels were significantly associated with the clinical features of RCC, especially prognostic significance.


The Japanese Journal of Urology | 2002

[PSA-related parameters in prostate cancer relapsed after endocrine therapy].

Seiji Nakata; Hirotomo Takahashi; Yutaka Takezawa; Mikio Kobayashi; Kazuhisa Matumoto; Nozomu Kosaku; Kiyotaka Kawashima

PURPOSE Prostate cancer is generally controlled by endocrine therapy even in an advanced state, but relapse may occur in many cases. Generally, the prognosis of a relapsed case is poor, but the prognosis differs case by case. We experienced 74 cases of prostate cancer relapsed after effective endocrine therapy, and investigated the relationship between the PSA-related parameters, clinical stage and prognosis. PATIENTS AND METHODS We investigated 74 prostate cancer patients whose PSA declined 10 ng/ml or lower by the treatment consisting of endocrine therapy, but relapsed later. Pre-treatment PSA, the value of PSA nadir, the period from the start of treatment to PSA nadir, the period from the start of treatment to relapse, PSA doubling time (PSA-DT) at relapse and PSA response to the second line therapy at relapse were calculated, and compared with the clinical stage and prognosis. The relationship between each PSA parameter and clinical stage was tested using the Kruskal-Wallis test and chi 2 test. Cancer-specific survival after relapse in stage D patients was calculated by the Kaplan-Meier method and differences in prognosis were tested using the Logrank test. RESULTS Pre-treatment PSA was significantly (p < 0.01) high, while the period from the start of treatment to relapse (p < 0.05) and PSA-DT at relapse (p < 0.01) was significantly short as the stage progressed. According to PSA response to the second line therapy at relapse, the rate of CR + PR was significantly (p < 0.05) high in clinical stage B + C group compared to clinical stage D group. The prognosis after relapse was significantly poorer in patients with relapse within 10 months after start of treatment than in those with relapse later, and in patients whose PSA-DT at relapse was shorter than 2 months than in those with a longer PSA-DT. CONCLUSIONS The period from the start of treatment to relapse, and PSA-DT at relapse were useful PSA-related parameters for predicting prognosis after relapse, and for determining the strategy of cancer therapy after relapse. Using these data, the physician can inform the family and the patient of the prognosis more accurately, so that they can adjust future plans.


International Urology and Nephrology | 1998

Noncancerous pulmonary lesions in patients with metastatic testicular germ cell cancer

K. Suzuki; Haruki Nakazato; Yoshihiro Ono; Yutaka Takezawa; Kouhei Kurokawa; T. Suzuki; Ichiro Yoshida; Hidetoshi Yamanaka

By thoracoscopic surgery, we confirmed pulmonary noncancerous lesions in two patients with metastatic nonseminomatous testicular germ cell cancer. The purpose of thoracoscopic surgery was complete resection of postchemotherapeutic residual tumour in one patient or a biopsy for new lesions during chemotherapy. Histological findings were normal lymph node and pulmonary fibrosis. We demonstrated CT findings of these lesions and made some discussion on management of disseminated testicular cancer.


The Prostate | 2003

Increased expression of bone morphogenetic protein-7 in bone metastatic prostate cancer.

Hiroshi Masuda; Yoshitatsu Fukabori; Katsuya Nakano; Yutaka Takezawa; Takanori cSuzuki; Hidetoshi Yamanaka

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