Toshitsugu Oka

Osaka National Hospital, Ōsaka, Ōsaka, Japan

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Publications (28)23.61 Total impact

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    ABSTRACT: Background and purpose: To evaluate the effectiveness of high-dose-rate interstitial brachytherapy (HDR-ISBT) as the only form of radiotherapy for high-risk prostate cancer patients. Patients and methods: Between July 2003 and June 2008, we retrospectively evaluated the outcomes of 48 high-risk patients who had undergone HDR-ISBT at the National Hospital Organization Osaka National Hospital. Risk group classification was according to the criteria described in the National Comprehensive Cancer Network (NCCN) guidelines. Median follow-up was 73 months (range 12-109 months). Neoadjuvant androgen deprivation therapy (ADT) was administered to all 48 patients; 12 patients also received adjuvant ADT. Maximal androgen blockade was performed in 37 patients. Median total treatment duration was 8 months (range 3-45 months). The planned prescribed dose was 54 Gy in 9 fractions over 5 days for the first 13 patients and 49 Gy in 7 fractions over 4 days for 34 patients. Only one patient who was over 80 years old received 38 Gy in 4 fractions over 3 days. The clinical target volume (CTV) was calculated for the prostate gland and the medial side of the seminal vesicles. A 10-mm cranial margin was added to the CTV to create the planning target volume (PTV). Results: The 5-year overall survival and biochemical control rates were 98 and 87 %, respectively. Grade 3 late genitourinary and gastrointestinal complications occurred in 2 patients (4 %) and 1 patient (2 %), respectively; grade 2 late genitourinary and gastrointestinal complications occurred in 5 patients (10 %) and 1 patient (2 %), respectively. Conclusion: Even for high-risk patients, HDR-ISBT as the only form of radiotherapy combined with ADT achieved promising biochemical control results, with acceptable late genitourinary and gastrointestinal complication rates.
    Full-text · Article · May 2014 · Strahlentherapie und Onkologie
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    ABSTRACT: Solitary fibrous tumor (SFT) is one of the mesenchymal tumor usually occurs in the pleura. Extrapleural occurrence of SFT is uncommon. We herein report an extremely rare case of 72-year old man with SFT originated in the urinary bladder. The tumor was incidentally discovered as a mass of 8.5 mm in diameter by a pelvic MRI. Cystoscopy revealed the protruding submucosal tumor in the center of the trigon. Transurethral resection was carried out. Pathological examination revealed a tumor composed of spindle cells with rich vascularity surrounded by abundant collagen fibers. The immunohistochemical findings showed a strong positivity to CD 34 and relatively weak positivity to Bcl-2. MIB-1 index indicated less than 3%, thus the tumor was diagnosed as a solitary fibrous tumor. The patient has no evidence of disease 16 months after the surgery. The current case was the first report in Japan and the twelfth worldwide.
    Preview · Article · Jul 2012 · Nippon Hinyōkika Gakkai zasshi. The japanese journal of urology

  • No preview · Article · May 2012 · Radiotherapy and Oncology
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    ABSTRACT: To validate 2009 TNM classification (7th edition) of renal cell carcinoma (RCC), we reevaluated our RCC database depends on 6th and 7th TNM staging and analyzed a prognostic divergence between subgroups. A study population of 350 patients with RCC was retrospectively reviewed based on the TNM classification both 6th and 7th editions. Cause-specific survival (CSS) in each group was estimated using Kaplan-Meier method. Applying the new TNM system, 336 patients were divided into pT1a 131, pT1b 105, pT2a 31, pT2b 13, pT3 a 38, pT3b 3, pT3c 0, pT4 14. Previously pT3b-staged 11 cases with renal vein involvement without vena caval extension were included into pT3a. Due to the positive direct invasion into the adrenal gland, previously pT3-staged six patients were changed to pT4. Kaplan-Meier curves revealed no significant differences in CSS between each a/b subgroups from pT1 to pT3. Particularly, no significant statistical value was recognized between pT2a and pT2b subgroups. Patients with direct adrenal invasion tended to show a less favorable prognosis than those with invasion beyond Gerota. (1) pT2 subdivision does not affect prognostic value. (2) Population imbalance is enhanced due to the pT 3 reclassification. (3) Direct adrenal invasion is compatible with pT4 category.
    No preview · Article · May 2012 · Nippon Hinyōkika Gakkai zasshi. The japanese journal of urology
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    ABSTRACT: To improve treatment conformity for prostate cancer, we investigated daily applicator displacement during high-dose-rate interstitial brachytherapy (HDR-ISBT). Thirty patients treated with HDR-ISBT as monotherapy were examined. All patients received a treatment dosage of 49 Gy per 7 fractions over 4 days. For dose administration, we examined 376 flexible applicators (1128 points) using our unique ambulatory implant technique. Using CT images with a 3-mm slice thickness, we calculated the relative coordinates of the titanium markers and the tips of the applicators. We calculated the distance between the center of gravity of the markers and the tips of the catheters, and compared the distances measured on the day of implantation and the second, third, and fourth treatment days. The mean displacement distance for all applicators was 4.3 ± 3.4 mm, 4.6 ± 4.1 mm, and 5.8 ± 4.5 mm at 21, 45, and 69 hours after initial planning CT. We used a 15-mm margin for needle displacement and only 2 points of 2 patients (16 mm and 18 mm at 69 hours, 2/1128 = 0.2%) exceeded this range. Almost patients (87%) showed the largest displacement within the first 21 hours. The relative doses that covered 100% of CTV (D100(CTV)) values compared with the initial treatment plan were reduced to 0.96 ± 0.08, 0.96 ± 0.08 and 0.94 ± 0.1 at 21, 45 and 69 hours. However, the relative D90(CTV) values kept acceptable levels (1.01 ± 0.02, 1.01 ± 0.03 and 1.01 ± 0.03). Cranial margin of 15 mm seems to be effective to keep D90(CTV) level if we do not do corrective action.
    No preview · Article · Apr 2012 · Journal of Radiation Research
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    Naoki Miyago · Yutaka Yasunaga · Toshitsugu Oka

    Preview · Article · Apr 2012 · International Journal of Urology
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    ABSTRACT: We describe an extremely rare case of poorly differentiated neuroendocrine carcinoma arising from the seminal vesicle. A 67-year-old man presented with a left humeral bone tumor resulting in a pathological fracture. Positron emission tomography scan disclosed a large pelvic tumor mimicking prostatic cancer invading into the seminal vesicle. Laboratory data showed an elevation of neuron-specific enolase, despite the normal prostate-specific antigen. Transrectal needle biopsy showed a poorly differentiated carcinoma of the right seminal vesicle and the metastasis of the pelvic lymph node. Immunohistochemical results were compatible with the features of neuroendocrine carcinoma; synaptophysin, chromogranin A and CD 56 were positive. The previously biopsied bone tumor was finally diagnosed as a metastasis. A systemic chemotherapy using etoposide and cisplatin failed. The patient died of cancer one-and-a-half years later.
    Preview · Article · Dec 2011 · International Journal of Urology
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    ABSTRACT: Effects of sorafenib in general clinical practice, especially those with patients of Asian ethnicity, have been rarely investigated. We assessed efficacy, safety and prognostic factors for progression-free survival in Japanese patients receiving sorafenib for advanced renal cell carcinoma. We performed a retrospective analysis of 159 Japanese patients with renal cell carcinoma. Progression-free survival was estimated by the Kaplan-Meier method. Objective response (per Response Evaluation Criteria in Solid Tumors) and safety were assessed. Cox proportional hazards model was used to identify independent prognostic factors for progression-free survival. The median progression-free survival was 9.0 months (95% confidence interval, 7.5-10.6 months). In 142 patients with measurable lesions, the objective response rate was 21.8%, and disease control was achieved in 85 (59.9%) patients. Adverse events of any grade occurred in 152 patients (95.6%). Most common adverse events causing discontinuation or interruption of sorafenib were hand-foot skin reaction (22%), rash (10.7%) and liver dysfunction (10.7%). Dose reduction or therapy interruption due to adverse events was required in 128 patients (80.5%). Univariate and multivariate analysis revealed that favorable prognosis according to Memorial Sloan-Kettering Cancer Center prognostic factors and relative dose intensity during the first month of treatment of ≥50% were significant factors for predicting superior progression-free survival with sorafenib treatment. Sorafenib was effective in Japanese patients with advanced renal cell carcinoma in general clinical practice and was tolerated although most patients required dose reduction or interruption of therapy. Future studies should establish new strategies for treatment without sacrificing both efficacy and patient quality of life.
    No preview · Article · Sep 2011 · Japanese Journal of Clinical Oncology
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    ABSTRACT: To introduce an effective ambulatory technique in high-dose-rate interstitial brachytherapy (HDR-ISBT) for prostate cancer, we investigated the displacement distance using our novel calculation method. Sixty-four patients treated with HDR-ISBT as monotherapy were examined. Of these, 4, 17, and 43 patients were administered treatment doses of 38 Gy (3 days), 49 Gy (4 days), and 54 Gy (5 days), respectively. For dose administration, we used 776 flexible applicators with a removable template (ambulatory technique). Using CT images, we calculated the relative coordinates of the metal markers and applicators. From these coordinates, to analyze displacement during treatment, we measured the distance between the tip of the needle applicator and the center of gravity of the markers along the average applicator vector. The median displacement distance for all applicators was 7 mm (range, -14 to 24), and that of each treatment schedule was 4, 6, and 9 mm for 38, 49, and 54 Gy, respectively. Of the 776 applicators, displacement of >10 mm was seen in 198 (26%) applicators and >15 mm in 57 (7%) applicators. Body height (p<0.0001) and anticoagulant usage (p<0.0001) were significant factors influencing displacement. We investigated needle applicator displacement using our unique method. Additional cranial margins are necessary if there is no repositioning of the dwell position. CT scanning should be performed daily during treatment for checking the position of the applicator to detect and rectify the issue of displacement.
    No preview · Article · Sep 2009 · Brachytherapy
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    ABSTRACT: We present an unusual magnetic resonance imaging finding of a 70-year-old man with the seminal vesicle tumor. The patient underwent radical nephrectomy for renal cell carcinoma 4 years ago. Laboratory data, including prostatic-specific antigen, ranged within normal limits. Transrectal needle biopsy disclosed a clear cell carcinoma, which was compatible with the original renal cell cancer. Vesiclectomy was performed. Pathohistologic examination confirmed a metastatic renal cell carcinoma of the seminal vesicle.
    No preview · Article · Aug 2009 · Urology
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    ABSTRACT: For safer treatment of seminal vesicles (SVs), we initiated a new technique using an anchor applicator for high-dose-rate interstitial brachytherapy (HDR-ISBT) of prostate cancer. Between January 2004 and March 2005, 23 intermediate- to high-risk patients were treated with HDR-ISBT as monotherapy. Transrectal ultrasonography guided implantation of the treatment applicator in and around the prostate gland and proximal SV. We used an "anchor" applicator to prevent posterior displacement of the SV. After insertion of the anchor applicator, the actual treatment applicator was implanted at the best position for optimal SV coverage. SV coverage was analyzed using a dose-volume histogram. Implantation of the applicator on the posterior side of the SV was successful for 43 of 46 SVs (93%). The median percentage of the SVs receiving the prescribed dose was 41% (range 11-86%). Only one case of acute Grade 2 toxicity (3%) was seen. Our anchor applicator technique for HDR-ISBT can separate the SV from the rectum. This is the first report of dose-volume histogram analysis of the SV for HDR-ISBT.
    No preview · Article · Jul 2007 · Brachytherapy
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    ABSTRACT: The aim of this study was to improve the performance status of prostate cancer patients during high-dose-rate interstitial brachytherapy (HDR-ISBT). To this end, we have developed a new ambulatory implant technique. Ten prostate cancer patients were treated with HDR-ISBT as monotherapy from October 2003 until March 2004. We utilized a new removable template, a flexible applicator with a nonmetallic bead and button stopper, and an inner catheter connecting the applicator and the transfer tube of the brachytherapy unit. We shortened the connector end of the flexible applicator to enable the patient to sit down and walk freely during the treatment time. All 10 patients could walk without any support. No problem in the application was observed. Our new ambulatory implant technique for HDR-ISBT was able to improve the performance status of prostate cancer patients.
    No preview · Article · Nov 2006 · Radiation Medicine
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    ABSTRACT: The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2004 and July 2005. The susceptibilities of these bacteria to various antimicrobial agents were measured. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1995 and 2003. The drug sensitivity of S. aureus in this year was similar to those in up to the previous year and S. aureus showed the best susceptibility to vancomycin (VCM) and arbekacin (ABK). The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous year. The susceptibility of E. coli to cephems in this year was generally good and was similar to those in up to the previous year. MIC90 of cefozopran (CZOP) was the most stable and 0.125 microg/mL or less since 1995. The susceptibility of E. coli to cefpirome (CPR) and cefotiam (CTM) also was good but to cefaclor (CCL), cefixime (CFIX), and cefpodoxime (CPDX) was largely decreased in complicated UTI groups. The sensitivity of E. coli to carbapenems also was good but to carumonam (CRMN) tended to decrease. The susceptibility of E. coli to quinolones, however, has largely changed and has decreased since 2003 in uncomplicated UTIs and 2000 in complicated UTIs. That was suggested the development of the resistance to the drug. The susceptibility of Klebsiella spp. to cefazolin (CEZ), CTM, CCL, CPDX, and cefditoren (CDTR) decreased in the previous year and recovered to the year before the previous year in this year. The susceptibility of Klebsiella spp. to other cephems was stable since 1995, especially against CZOP, the highest sensitivity (MIC90: < or = 0.125 microg/mL) was maintained. The susceptibility of Klebsiella spp. to carbapenems and CRMN also was good. The susceptibility of Klebsiella spp. to aminoglycosides was lower than to CZOP but was stable since 1995. The susceptibility of P. aeruginosa was generally low and has largely changed against the majority of the agents since 1995. The susceptibility of P. aeruginosa isolated from uncomplicated UTIs has largely changed against ceftazidime (CAZ), cefsulodin (CFS), CZOP, imipenem (IPM), meropenem (MEPM), aztreonam (AZT), CRMN, gentamicin (GM), and tobramycin (TOB). The susceptibility of P. aeruginosa isolated from complicated UTIs has largely changed against CSF, CZOP, MEPM, GM, and ciprofloxacin (CPFX). The susceptibility of P. aeruginosa isolated from complicated UTIs has been stable against amikacin (AMK). For annual changes in MIC50, TOB and IPM had a relatively stable and high activity (MIC50: 0.5-2 microg/mL).
    No preview · Article · Aug 2006 · The Japanese journal of antibiotics
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    ABSTRACT: The bacterial strains isolated from 490 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2004 and July 2005. The susceptibilities of them to many kinds of antimicrobial agents were measured. Of them, 577 strains were estimated as causative bacteria and used for the measurement. The strains consisted of 156 gram-positive bacterial strains (27.0%) and 421 gram-negative bacterial strains (73.0%). Against Staphylococcus aureus, arbekacin (ABK), vancomycin (VCM) showed the strongest activity and prevented the growth of all strains with 2 microg/mL. Against Enterococcus faecalis, ampicillin (ABPC) and VCM showed a strong antibacterial activity. The antibacterial activity of cephems to Escherichia coli was generally good, and especially cefozopran (CZOP) and cefpirome (CPR) showed the strongest activity (MIC90: < or = 125 microg/mL). Quinolone resistant E. coli [MIC of ciprofloxacin (CPFX): > or = 4 microg/mL] was detected at frequency of 18.8%, which was higher than that in the last year. Against Klebsiella pneumoniae, CZOP, meropenem (MEPM), and carumonam (CRMN) showed the strongest activity and prevented the growth of all strains with 0.125 microg/mL or less. The antibacterial activity of the other cephems was relatively good, and decrease in their activity observed in the last year study was not recognized. Against Serratia marcescens, imipenem (IPM) and gentamicin (GM) had the strongest antibacterial activity. Against Proteus mirabilis, CRMN showed the strongest activity and prevented the growth of all strains with 0.125 microg/mL or less. MEPM prevented the growth of all strains with 0.25 microg/mL. Next, cefmenoxime (CMX), ceftazidime (CAZ), CZOP, cefixime (CFIX), cefpodoxime (CPDX), and cefditoren (CDTR) showed a strong activity. The antibacterial activity of the drugs to Pseudomonas aeruginosa was generally low, and MIC90 of all the drugs was ranged from 32 to > 128 microg/mL except IPM and MEPM having 16 microg/mL. The antibacterial activities of CZOP and CAZ were considered to be relatively good on MIC50 comparison (MIC50: 2 microg/mL).
    No preview · Article · Jun 2006 · The Japanese journal of antibiotics
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    ABSTRACT: Six hundred six bacterial strains isolated from 490 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2004 and July 2005. The frequency of bacteria isolation stratified with patient clinical background was compared. The clinical background investigated included sex, age, type of infections, timing of antibiotics administration, and presence or absence of surgery affecting a decrease in defense against infection. The bacterial strains were stratified with the age and sex of the patients and the types of infections. In males, the number of patients aged less than 60 years was few and the complicated UTIs without indwelling catheter was observed most frequently. In females, the number of patients aged less than 60 years was comparatively more than in males. In all of ages except 0-19 and > or = 80 years, the ratio of the uncomplicated UTIs was high, accounting for 44.1-90.0% of all types of infections. In the present time, the bacteria most frequently isolated were Escherichia coli. Pseudomonas aeruginosa and Enterococcus faecalis also were relatively frequently isolated. E. coli most frequently isolated with the uncomplicated UTIs and P. aeruginosa and E. faecalis most frequently isolated with the complicated UTIs. With respect to the relation of these results to the age of the patients, in the uncomplicated UTIs, the isolation frequency of E. coli was the highest in all age groups except 0-19 years, accounting for 50% or higher. In the complicated UTIs without indwelling catheter, the isolation frequency of E. coli tended to be high in all age groups. In the complicated UTIs with indwelling catheter, P. aeruginosa were more frequently isolated. In comparison of causative bacteria in UTIs between before and after the administration of antibiotics, P. aeruginosa increased after the administration in any types of UTIs. In comparison of causative bacteria in UTIs with or without surgery, E. coli was more frequently isolated in the patients without surgery, while P. aeruginosa and E. faecalis were more frequently isolated in the patients with surgery in any UTIs.
    No preview · Article · Jun 2006 · The Japanese journal of antibiotics
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    ABSTRACT: Seven hundred and nineteen bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2002 and July 2003. The frequency of bacteria isolation divided with patient clinical background was compared. The clinical background investigated included sex, age, type of infections, timing of antibiotics administration, and presence or absence of surgery affecting a decrease in defense against infection. The bacterial strains were divided with the age and sex of the patients and the types of infections. In males, the number of patients aged less than 50 years was few and the complicated UTIs without indwelling catheter was observed most frequently. Number of patients aged 20-39 years was greater in female than male. In all of ages except 0-9 and 70-79 years, the ratio of the uncomplicated UTIs was high, accounting for 44.4-91.7% of all types of infections. In the present time, the bacteria most frequently isolated were Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis also were relatively frequently isolated. E. coli was most frequently isolated from the uncomplicated UTIs, and P. aeruginosa and E. faecalis were frequently isolated from the complicated UTIs with indwelling catheter. With respect to the relation of these results to the age of the patients, in the uncomplicated UTIs, the isolation frequency of E. coli was the highest in all age groups, accounting for 40% or higher. In the complicated UTIs without indwelling catheter, the isolation frequency of E. coli decreased with aging of the patients but still was the highest in all age groups. In the complicated UTIs with indwelling catheter, the isolation frequency of E. coli was lower than in the uncomplicated UTIs in all age groups and P. aeruginosa and E. faecalis were more frequently isolated. In comparison of causative bacteria in UTIs between before and after the administration of antibiotics, P. aeruginosa increased after the administration in any types of UTIs. In comparison of causative bacteria in UTIs with or without surgery, E. coli was more frequently isolated in the patients without surgery, while P. aeruginosa and E. faecalis were more frequently isolated in the patients with surgery in any UTIs.
    No preview · Article · Jan 2006 · The Japanese journal of antibiotics
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    ABSTRACT: The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from 565 patients diagnosed as urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of these bacteria to various antimicrobial agents were examined. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1994 and 2002. The drug sensitivity of S. aureus in this year was similar to those in up to the previous years and S. aureus showed the best susceptibility to vancomycin. The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous years. The drug sensitivity of E. coli in this year was generally good except penicillins and was similar to those in up to the previous years. Among cephems, cefozopran (CZOP) and cefpirome (CPR) showed the highest potency activity (MIC90: < or = 0.125 microg/mL). An antibacterial activity of cefotiam (CTM) was stable for 10 years and was fine (MIC0: < or = 0.5 microg/mL). The sensitivity of E. coli to carbapenems and carumonam (CRMN) also was good like to CZOP. The sensitivity of the complicated UTIs group to quinolones, however, has decreased after 2000 and it was suggested that the resistance to the drug has developed. Kiebsiella spp. showed a decrease in the susceptibility to some of cephems. The drugs indicating a big decrease in the sensitivity were cefazolin, CTM, cefaclor, and cefpodoxime. Imipenem, carbapenems, also indicated a decrease in the sensitivity. The susceptibility of the strain to the other drugs was similar to that in up to the previous years. Among them, CZOP maintained good susceptibility (MIC90: > or = 0.125 microg/mL against uncomplicated UTIs, 0.25 microg/mL against complicated UTIs) like meropenem. The drug sensitivity of P. aeruginosa was generally low and was not much different from that in up to the previous years.
    No preview · Article · Dec 2005 · The Japanese journal of antibiotics
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    ABSTRACT: A 75-year-old male was diagnosed as prostate cancer (serum PSA: 4,772 ng/ml, Gleason score: 4 + 4 = 8) with multiple bone metastases. And he noticed a painless mass of the frontal neck a month before the diagnosis. Computed tomography of the neck showed a tumor in the thyroid cartilage. Biopsy of the neck tumor revealed metastasis of prostate cancer by positive PSA staining. Metastasis of malignant tumor to cartilaginous tissue is extremely rare because there are usually no vessels in it. Only 4 cases of the metastasis of prostate cancer to the thyroid cartilage have been reported. It was thought that tiny bone marrows were formed in the ossified cartilage and it caused hematogenous metastasis.
    Preview · Article · Dec 2005 · Nippon Hinyōkika Gakkai zasshi. The japanese journal of urology
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    ABSTRACT: The bacterial strains isolated from 565 patients diagnosed as having urinary tract infections (UTIs) in 14 institutions in Japan were collected between August 2003 and July 2004. The susceptibilities of them to many kinds of antimicrobial agents were investigated. Of them, 701 strains were estimated as prophlogistic bacteria and used for the investigation. The strains consisted of 258 Gram-positive bacterial strains (36.8%) and 443 Gram-negative bacterial strains (63.2%). Against Staphylococcus aureus, vancomycin (VCM) showed the strongest activity and prevented the growth of all strains with 2 microg/mL. Against Streptococcus agalactiae, ampicillin (ABPC), cefozopran (CZOP), imipenem (IPM), and clarithromycin (CAM) showed a strong activity and the MIC90 was 0.125 microg/mL or less. Against Enterococcus faecalis, VCM, ABPC, and IPM showed a strong antibacterial activity. The antibacterial activity of cephems to Escherichia coli was generally good, and especially CZOP and cefpirome (CPR) showed the strongest activity (MIC90: < or = 0.125 microg/mL). Quinolone resistant E. coli [MIC of ciprofloxacin (CPFX): > or =4 microg/mL] was detected at frequency of 15.7%, which was higher than that in the last year. Against Klebsiella pneumoniae, meropenem (MEPM) showed the strongest activity and next, the antibacterial activity of CRMN and CZOP was good. The antibacterial activity of the other cephems, however, significantly decreased, compared with that evaluated in last year. Against Serratia marcescens, MEPM had the strongest antibacterial activity. Against Proteus mirabilis, MEPM and CRMN showed the strongest activity and prevented the growth of all strains with 0.125 microg/mL or less. Nest, cefmenoxime (CMX), ceftazidime (CAZ), cefixime (CFIX), cefpodoxime (CPDX), CPR, CZOP, and cefditoren (CDTR) showed a strong activity. The antibacterial activity of the drugs to Pseudomonas aeruginosa was generally low, and MIC90 of all the drugs was ranged from 32 to < or = 256 microg/mL except IPM and amikacin (AMK) having 16 microg/mL. The antibacterial activity of CZOP was relatively good (MIC50: 2 microg/mL).
    No preview · Article · Dec 2005 · The Japanese journal of antibiotics
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    ABSTRACT: The bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as urinary tract infections (UTIs) in 13 institutions in Japan were supplied between August 2002 and July 2003. The susceptibilities of these bacteria to various antimicrobial agents were examined. The bacteria were divided into 2 groups consisting of uncomplicated UTIs and complicated UTIs (with and without indwelling catheter) based on their isolation origins. The results were compared with those obtained between 1993 and 2001. The drug sensitivity of S. aureus in this year was similar to those in up to the previous year and S. aureus showed the best susceptibility to vancomycin. The drug sensitivity of E. faecalis in this year also was similar to those in up to the previous year. The drug sensitivity of E. coli in this year was generally good except penicillins and was similar to those in up to the previous year. Among cephems, cefozopran (CZOP) and cefpirome (CPR) showed the highest potency (MIC90: < or = 0.125 microg/mL). An antibacterial activity of cefotiam (CTM) was similar to it in 10 years ago and was fine (MIC90: < or = 1 microg/mL). The sensitivity of E. coli to carbapenems and carumonam (CRMN) also was good like to CZOP. However, the sensitivity of the complicated UTIs group to quinolones decreased after 2000 and was suggested to develop the resistance to the drug. The drug sensitivity of Klebsiella spp. in this year also was similar to those in up to the previous year. The bacteria showed good susceptibility (MIC: < or = 0.125 microg/mL) to cefmenoxime (CMX), CPR, cefixime (CFIX), flomoxef (FMOX), and CZOP among cephems. The drug sensitivity of P. aeruginosa was generally low. Most of the bacteria were little sensitive to cephems except CZOP and ceftazidime (CAZ). The sensitive bacteria to CZOP and ceftazidime (CAZ) were observed to be 26.8% (15/56 strains) and 39.3% (22/56 strains) in complicated UTIs group, respectively. The sensitivity profile of P. aeruginosa to the other tested drugs was not much different from that in up to the previous year. However, the sensitivity of the bacteria to carbapenems tended to decrease after 2000, and the low sensitive strains (MIC: > or = 256 microg/mL) were detected at 22.2% (2/9 strains) in the uncomplicated UTIs group and 3.6% (2/56 strains) in the complicated UTIs group.
    No preview · Article · Sep 2004 · The Japanese journal of antibiotics

Publication Stats

158 Citations
23.61 Total Impact Points

Institutions

  • 2004-2014
    • Osaka National Hospital
      Ōsaka, Ōsaka, Japan
  • 2003
    • Sapporo Medical University
      • Division of Urology
      Sapporo, Hokkaidō, Japan