Masaaki Hamano

Chiba University, Chiba-shi, Chiba-ken, Japan

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Publications (5)9.4 Total impact

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    ABSTRACT: Most clinical pathways in treating cancers in Japan are based on individual physician's personal experiences rather than on an empirical analysis of clinical data such as benchmark comparison with other hospitals. Therefore, these pathways are far from being standardized. By comparing detailed clinical data from five cancer centers, we have observed various differences among hospitals. By conducting benchmark analyses, providing detailed feedback to the participating hospitals and by repeating the benchmark a year later, we strive to develop more standardized clinical pathways for the treatment of cancers. The Cancer Quality Initiative was launched in 2007 by five cancer centers. Using diagnosis procedure combination data, the member hospitals benchmarked their pre-operative and post-operative length of stays, the duration of antibiotics administrations and the post-operative fasting duration for gastric, colon and rectal cancers. The benchmark was conducted by disclosing hospital identities and performed using 2007 and 2008 data. In the 2007 benchmark, substantial differences were shown among five hospitals in the treatment of gastric, colon and rectal cancers. After providing the 2007 results to the participating hospitals and organizing several brainstorming discussions, significant improvements were observed in the 2008 data study. The benchmark analysis of clinical data is extremely useful in promoting more standardized care and, thus in improving the quality of cancer treatment in Japan. By repeating the benchmark analyses, we can offer truly clinical evidence-based higher quality standardized cancer treatment to our patients.
    Japanese Journal of Clinical Oncology 01/2011; 41(1):2-9. · 1.90 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the efficacy and toxicities of the gemcitabine and paclitaxel combination regimen as second-line chemotherapy for patients with advanced or metastatic urothelial carcinoma (UC) who have previously been treated with platinum-based chemotherapy for the metastatic disease. Thirty-three patients with advanced or metastatic UC who had received platinum-based chemotherapy were treated with an outpatient gemcitabine and paclitaxel combination regimen. A dose of 180 mg/m(2) paclitaxel was administered by intravenous (IV) infusion on Day 1, and 1000 mg/m(2) gemcitabine was administered by IV on Days 1, 8 and 15.The course was repeated every 28 days. Patients were evaluated after every 2 cycles of therapy using computed tomography. Of the 33 patients enrolled in this study, 30 could be evaluated to determine treatment efficacy; 10 had an objective response [overall response rate: 33.3%, 95% confidence interval (CI), 19.2-51.2%]. The median overall survival was 11.3 months (95% CI, 7.2-13.6 months). The chemotherapy sensitivity differed with disease site. The response rates of lung and bone metastases were 27% and 14%, and the progressive disease (PD) rates of lung and bone metastases were 13% and 14%, respectively. On the other hand, the response rate of liver metastasis was 14%, and its PD rate was 57%. None of the patients (n = 3) with adrenal metastasis responded to this regimen. Toxicities were mild, and no life-threatening complications occurred. Gemcitabine and paclitaxel combination therapy is a tolerable and active regimen for patients with advanced UC after failure of platinum-based chemotherapy.
    Japanese Journal of Clinical Oncology 03/2009; 39(4):244-50. · 1.90 Impact Factor
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    ABSTRACT: Thirty-nine renal cell carcinoma patients with bony metastasis were intensively treated, primarily with immunotherapy using natural type interferon-alpha (IFN-alpha) continuous subcutaneous injection in combination with surgical resection and radiation therapy. Long-term survival was achieved, including three patients with complete response. The results of this study are presented. The mode of administration of IFN-alpha was as follows: natural-type IFN-alpha (25,000,000 IU) was dissolved in 60 mL of distilled water and administered via continuous subcutaneous injection (0.5 mL/h) as 'one course of the treatment'. Two courses of IFN-alpha therapy were given 2 weeks preoperatively, while 13 courses of IFN-alpha therapy were given postoperatively (one course per week). Thus, 15 courses of IFN-alpha therapy were administered during the trial period. Thereafter, IFN-alpha therapy was repeated either every week or every other week depending on the condition of the patient. Additionally, blood levels of IFN-alpha were monitored for four patients following initiation of IFN-alpha continuous subcutaneous injection therapy. Immediately after injection of IFN-alpha, blood levels of IFN-alpha started to rise, reaching 40.5 IU/mL on average at 24 h after initiation of IFN-alpha therapy. Thereafter, blood levels of IFN-alpha remained high and measurable blood levels of IFN-alpha were maintained for up to 24 h after completion of IFN-alpha injection. As a whole, IFN-alpha was detectable for 6-8 days and Cmax (maximum blood concentration of IFN) was 167 IU/mL. Thirty-nine patients with bony metastases were treated as follows: IFN mono-therapy (19 patients), IFN and radiation therapy (15 patients) and IFN and surgical resection of bony metastases (five patients). Fourteen patients survived and the details of these 14 patients are as follows: complete response in three cases, partial response in two, no change in six and progressive disease in three. Twenty-five patients died of renal cell carcinoma. The overall 5-year survival rate was 35.0%. These findings indicate that IFN-alpha continuous subcutaneous injection therapy is a useful modality for renal cell carcinoma patients with bony metastasis if administered in combination of radical nephrectomy and radiation therapy.
    International Journal of Urology 06/2005; 12(5):442-8. · 1.73 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the cancer detection rate in patients with a prostate-specific antigen (PSA) level of 2.5 to 20 ng/ml, using transperineal ultrasound-guided systematic biopsy of the prostate. Three hundred consecutive patients with PSA levels of 2.5 to 20 ng/ml underwent transperineal ultrasound-guided 12-core systematic biopsy of the prostate. Prostate cancer was detected in 108 of the 300 patients (36.0%). The cancer detection rates in patients with total PSA levels of 2.5-4.0, 4.01-10.0 and 10.01-20.0 ng/ml were 18.2%, 31.0%, and 50.0%, respectively. The cancer detection rates in patients with prostate volumes of less than 30 cc and over 50 cc were almost 50%, and 13.3%, respectively. The cancer detection rate in patients with a PSA density (PSAD) of less than 0.10 ng/ml per cc was only 5.6%, and no prostate cancer was detected in patients with a free-to-total PSA ratio (% f PSA) over 40%. We demonstrated a high prostate cancer detection rate by the transperineal ultrasound-guided 12-core systematic biopsy method in patients with PSA levels of 2.5 to 20 ng/ml. Accordingly, if the number of core biopsies is further increased overall, except in patients with a large prostate volume, and if the indication for biopsy is decided based on the PSAD and %f PSA, then the cancer detection rate by the present method may be further improved, with fewer unnecessary biopsies.
    International Journal of Clinical Oncology 05/2005; 10(2):117-21. · 1.73 Impact Factor
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    ABSTRACT: The metastatic ability of a Dunning R-3327 rat prostate cancer subline (AT6.3) was suppressed by the introduction of human chromosome 10, when these hybrid cancer cells were injected subcutaneously into nude mice (Nihei et al., Genes Chromosomes Cancer 14:112-119, 1995). The present study was undertaken to clarify which step of metastasis was suppressed in the human chromosome 10-containing microcell hybrids (AT 6.3-10 clones). Gelatin zymography, an in vitro invasion assay using a Boyden chamber and an intravenous metastasis assay involving the injection of hybrid cells into nude mice were performed. Gelatin zymography revealed that AT6.3-10 microcell hybrid clones expressed the 72 kD type IV collagenase (MMP-2) at an almost equal level as control microcell hybrid clones. Both the invasiveness as measured by the invasion assay and the number of lung metastases as measured by the intravenous metastasis assay of AT6.3-10 hybrid clones were significantly less than those of the AT6.3 parental clone. The human chromosome 10 suppresses both the local invasion and the metastatic process after entry into the blood circulation of rat prostate cancer. This decrease in local-invasive ability does not seem to require a decrease in MMP-2 activity.
    Asian Journal of Andrology 07/2002; 4(2):123-9. · 2.14 Impact Factor