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Yukihiko Ohishi

Publications and source records attributed to Yukihiko Ohishi.

11 recordsLinked to original sources
PubMed2006

Percutaneous cryoablation of renal cell carcinoma guided by horizontal open magnetic resonance imaging.

BACKGROUND: Cryoablation is a treatment option for some patients with small exophytic lesions of the kidney. The purpose of this study is to determine the feasibility, safety, and intermediate-term treatment outcome of percutaneous cryoablation of renal cell carcinoma guided by horizontal open magnetic resonance imaging (MRI). METHODS: We prospectively used cryoablation to treat 13 patients with radiographically confirmed enhancing small, solid renal tumors (< or =4.8 cm). An argon gas-based cryoablation system was used. One to four cryoprobes with 2 or 3-mm diameters were placed percutaneously into the tumor under local anaesthesia and MRI guidance. Ice ball dimensions were monitored by 2-D MR images. Double freeze-thaw cycles were conducted throughout the procedure. After successful cryoablation, patients were followed on a regular basis to evaluate the treatment's clinical outcome. RESULTS: Median follow up from time of procedure is 35 months (range, 28-42). In all cases the entire procedure was accomplished without significant morbidity or complications. A mild retroperitoneal hematoma, which subsided spontaneously, was noted in one patient. Follow-up dynamic computed tomography (CT) at 3 months after operation confirmed the absence of enhancement in resolved tumor masses for 11 of 13 cases. None of these 11 patients had clinical evidence of recurrent disease at last follow up. The remaining two patients had lesions with some enhanced areas. Subsequent partial nephrectomy histologically confirmed the presence of vital tumor in, respectively, the center and the periphery of the residual masses. One of these patients developed multiple lung and ipsilateral adrenal metastases 13 months after surgical resection. CONCLUSIONS: Percutaneous cryoablation of small renal cell carcinomas under horizontal open MRI guidance appears to be safe and feasible. An intermediate-term follow up continues to demonstrate efficacy in most patients; however, a few patients experience incomplete ablation with risk of treatment failure. The ideal candidates for this procedure still need to be determined in longer follow up with diligent observation.

Adult↗
PubMed2005

[Primary, nonviral, hepatocellular carcinoma in patients with prostate cancer treated by hormone therapy: 2 case reports].

We studied two cases of primary, hepatocellular carcinoma (HCC) that occurred following hormone therapy (estrogen therapy in one case and total androgen blockade therapy in another) for stage D2 prostate cancer. Prostate cancer is considered to be hormone-dependent, and androgens appear to be important hormonal factors. However, hepatocellular carcinoma has been shown to have both estrogen and androgen receptors, suggesting that this may be dependent on estrogen or androgen. Reported here are two unique cases of hepatocellular carcinoma in patients with prostate cancer; the pathogenesis of HCC in these patients was suspected to be related to diethylstilbestrol (DES) therapy and antiandrogen therapy for their prostate cancer.

Aged↗
PubMed2004

[Prostatic cancer in a young adult: a report of 2 cases].

Patients younger than 45 years with prostate cancer are rare. Between 1999 and 2002, we studied two cases of prostate cancer in men aged under 45 years. Case 1; a 45-year-old man admitted with the chief complaint of urination disorder. Serum level of prostate-specific antigen (PSA) was 5,000 ng/ml or higher. Transrectal needle biopsy of the prostate revealed moderately differentiated adenocarcinoma. Computed tomography (CT) and bone scan showed para-aorta lymph node metastasis and bone metastasis. Hormone therapy was performed. Case 2; a 37-year-old man admitted with the chief complaint of pollakisuria and sense of residual urine. Serum level of prostate-specific antigen (PSA) was 24 ng/ml. Magnetic resonance imaging (MRI) showed that the prostate tumor invaded the bladder wall. Transrectal needle biopsy revealed poorly differentiated adenocarcinoma. Hormone therapy and radiation therapy were performed. Twenty-one cases reported in Japan in addition to the present cases are reviewed.

Adenocarcinoma↗
PubMed2004

[Urologic area].

In this review, the clinical experience of a three-dimensional(3D) image at urologic area are described. There are some methods for reconstructive 3D image of Multi-slice CT. Maximum intensity projection (MIP) is usefulness for detection of vascular anatomy. Multi-planar reconstruction (MPR) is usefulness for relation with circumference organs. Therefore the opportunities of angiography decreased. It seems that an applied range of a 3D image spreads more in future.

Female Urogenital Diseases↗
PubMed2003

Flutamide-induced hepatic dysfunction in relation to steady-state plasma concentrations of flutamide and its metabolites.

The frequency, severity, and outcome of flutamide-induced hepatic injury were prospectively evaluated in 55 patients with prostate cancer who received 125 mg of flutamide 3 times a day (daily dose: 375 mg) combined with an agonistic analogue of luteinizing hormone-releasing hormone. In addition, we examined plasma and urine concentrations of flutamide and its major metabolites 4 weeks after the beginning of flutamide therapy, and evaluated their significance in predicting flutamide-induced hepatic dysfunction. Hepatic function could be assessed in 50 patients and hepatic dysfunction during therapy was observed in 9 patients (18%); 3 patients (6%) were classified as having moderate liver dysfunction and 6 (12%) were classified as having mild liver dysfunction. The steady-state plasma levels of flutamide and its biologic active metabolite, hydroxyflutamide (OH-Flu), were not related to hepatic dysfunction. However, the concentration of another major metabolite, 4-nitro-3-(trifluoromethyl)phenylamine (FLU-1) was considerably higher in 2 patients who developed clinically significant hepatic dysfunction. These findings suggest that clinically significant hepatic dysfunction could be induced in patients with compromised flutamide metabolism, which leads to a high concentration of FLU-1. Based on results of this study, we propose that plasma FLU-1 levels are one of the predictive factors for flutamide-induced hepatic dysfunction. This hypothesis will be confirmed in a large-scale study.

Aged↗
PubMed2003

Antitumor immunity against bladder cancer induced by ex vivo expression of CD40 ligand gene using retrovirus vector.

The interaction between CD40 ligand (CD40L) and CD40 on antigen-presenting cells is essential for the initiation of antigen-specific T-cell responses. In order to clarify whether the expression of CD40L in tumor cells might be useful as a systemic therapy against bladder cancer, we investigated the antitumor immunity induced by CD40L in the mouse bladder cancer cell line MBT2. MBT2 was transduced by the retroviral vector expressing CD40L (MBT2-CD40L). Mouse bone marrow-derived dendritic cells cocultured with MBT2-CD40L cells produced eight times more IL-12 than those cocultured with parental MBT2 cells. In animal studies, subcutaneously inoculated MBT2-CD40L cells were rejected promptly. The vaccination of MBT2-CD40L cells induced antitumor immunity against parental tumors at a distant site. However, the antitumor effect of MBT2-CD40L inoculation was insufficient against pre-existing tumors. In the vaccination model, antibody ablation studies revealed that CD4(+) T cells were required for antitumor immunity, and tumor-specific cytotoxicity of sera was demonstrated. These data demonstrated that the antitumor immunity induced by CD40L was effective in the vaccination model and suggested that immunogene therapy using CD40L may be a new strategy of systemic therapy against bladder cancer.

Animals↗
PubMed2003

Usefulness of tamsulosin hydrochloride and naftopidil in patients with urinary disturbances caused by benign prostatic hyperplasia: a comparative, randomized, two-drug crossover study.

BACKGROUND: The aim of the study presented here was to stratify drug therapy for patients with benign prostatic hyperplasia (BPH) displaying various voiding symptoms. METHODS: Two different alpha1-adrenoceptor antagonists; tamsulosin hydrochloride (Tam) and naftopidil (Naf ), were administered to 96 patients with BPH for 8 weeks in a crossover study. RESULTS: With the administration of both drugs, the International Prostate Symptom Score (I-PSS) significantly decreased and the maximum urinary flow significantly increased. Whereas Naf monotherapy decreased the I-PSS for storage symptoms, Tam monotherapy decreased the I-PSS for voiding symptoms. In both the Naf-to-Tam and Tam-to-Naf groups, crossover was effective when the initial drug was judged subjectively and objectively to have been ineffective. Compliance was acceptable with both drugs. CONCLUSION: Our results show that either Naf or Tam can be used to treat patients on the basis of objective and subjective assessment of voiding symptoms. Our findings should be helpful for patient guidance and treatment of BPH.

Adrenergic alpha-Antagonists↗
PubMed2003

Questionnaire survey of Japanese urologists concerning the diagnosis and treatment of chronic prostatitis and chronic pelvic pain syndrome.

OBJECTIVES: We performed a questionnaire survey to investigate various issues in the diagnosis and treatment of chronic prostatitis/chronic pelvic pain syndrome by Japanese urologists and to clarify the circumstances surrounding prostatitis in Japan. METHODS: Japanese urologists (n = 1869) were surveyed by mail using a 17-item questionnaire to determine current diagnostic and treatment practices for prostatitis/chronic pelvic pain syndrome. RESULTS: Only 1.5% (11/739) of urologists diagnosed chronic prostatitis/chronic pelvic pain syndrome using the 4-glass test, while most did so using the 2-glass test (voided bladder [VB]2 and VB3, or VB2 and expressed prostatic secretion [EPS]). Approximately half (55.2%; 412/746) did not perform urine cultures to differentiate chronic bacterial prostatitis from chronic abacterial prostatitis/chronic pelvic pain syndrome. Approximately half (46%; 343/746) did not count the number of leukocytes in VB2 or VB3/EPS to differentiate chronic abacterial prostatitis from chronic pelvic pain syndrome. Although many urologists (63.8%; 459/720) thought that chronic abacterial prostatitis/chronic pelvic pain syndrome was not an infectious disease, many chose antimicrobial agents as the primary treatment. More than half (52.2%; 384/735) of all urologists felt pessimistic about dealing with chronic prostatitis/chronic pelvic pain syndrome compared to treating benign prostatic hypertrophy or prostate cancer, because of the high number of complaints by patients and their own lack of confidence in diagnosing and treating the condition. CONCLUSION: There is much confusion and frustration among Japanese urologists about chronic prostatitis/chronic pelvic pain syndrome. Further studies are needed to elucidate its etiology and pathogenesis, and to establish guidelines for its diagnosis and treatment.

Chronic Disease↗
PubMed2002

[A case of adrenocortical carcinoma with masculinization, obtaining long prognosis with surgical treatment alone].

A 28 year-old woman presented right upper abdominal pain. She had been pointed out her masculinization and amenorrhea. CT scan and magnetic resonance imaging showed right adrenal tumor. In the endocrinological study, the serum cortisol and testosterone was elevated. Transabdominal right adrenalectomy and nephrectomy was carried out and histopathological diagnosis was adrenocortical carcinoma. The masculine symptom had disappeared after the operation and she has been without recurrence for five years.

Adrenal Cortex Neoplasms↗
PubMedDate not supplied

Treatment of patients with superficial bladder cancer by intravesical instillation of anticancer drugs plus oral chemotherapy following TUR-Bt: a randomized controlled trial.

We conducted a randomized controlled trial to compare local recurrence rate after transurethral resection of superficial bladder cancer treated by either intravesical instillation of an anticancer drug alone (method A) and the intravesical instillation plus oral chemotherapy (doxifluridine, 5'-DFUR, an intermediate metabolite of capecitabine) (method B). Results between groups showed no difference in recurrence-free survival curves in 196 patients subjected to primary analysis. However, patients subjected to secondary analysis (method B, over 3 months administration of 5'-DFUR) showed a significantly better prognosis than method A (p=0.0244, Wilcoxon). Regarding correlation between thymidine phosphorylase (TP, an enzyme to convert 5'-DFUR to 5-fluorouracil) level and prognosis, method A patients showed poorer prognosis in higher TP level cases than in lower TP levels. However, there was no significant difference in prognosis between those with higher and lower TP levels. In method B patients, there was no difference in prognosis between those with higher and lower TP levels. Method A patients tended to show a slightly better prognosis than those with lower TP levels, while method B patients tended to have a slightly better prognosis with higher TP levels, but no significant difference was observed. These findings suggested 5'-DFUR showed a mild efficacy in patients with higher TP levels and that patients with higher TP levels resulted in poorer prognosis.

Administration, Intravesical↗