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S Kuwao

Publications and source records attributed to S Kuwao.

At least 55 records · Page 3Linked to original sources
PubMed1997

Impact of life expectancy and tumor doubling time on the clinical significance of prostate cancer in Japan.

Theoretical projected prostate cancer volume at the time of expected death was determined based on patient age and index cancer volume at diagnosis, assumed cancer volume doubling time and life expectancy of the Japanese male population. Based on the data obtained, evaluation was made of the results for 104 consecutive radical prostatectomy cases with no prior treatment. Clinically insignificant cancer in 104 prostatectomy specimens was found to occur at 4.8, 10.6, 15.4 and 26.9% for tumor doubling times of 2, 3, 4 and 6 years, respectively. Assuming a 2-year doubling time with clinically insignificant cancer excluded, only 36.4% of significant cancers could be considered potentially curable and with a 3-year doubling time, 32.3%. For 4- and 6-year doubling times, only 30.7 and 25.0% of the clinically insignificant cancers were potentially curable, respectively. Approximately half of these insignificant cancers were clinically stage T1c disease. In all stage T1c cases, 8.8-47.1% was considered insignificant, depending on tumor doubling time. Patient life expectancy and tumor doubling time significantly determine the outcome of treatment for prostate cancer, especially in elderly males with higher risk of mortality. The outcome of radical prostatectomy is less satisfactory with these factors taken into consideration. Many patients with stage T1c disease may eventually prove to require no treatment.

Aged↗
PubMed1996

Deoxyribonucleic acid ploidy status as no basis for pathologic stage prediction in clinically resectable prostate cancer.

OBJECTIVES: Assessment of deoxyribonucleic acid (DNA) ploidy status of a tumor as a means for predicting pathologic stages in prostate cancer. METHODS: DNA ploidy of each focus of a cancer in 70 radical prostatectomy specimens was determined by nuclear image analysis. DNA ploidy was compared with the pathologic features of tumors. RESULTS: One hundred three individual cancers in 70 patients were used for DNA ploidy analysis. Of these, 39 (38%) were diploid and 64 (62%), nondiploid. DNA ploidy was weakly correlated with increase in tumor volume (P = 0.049) but not tumor grade. The relationship between DNA content and extraprostatic spread was not statistically significant. Increase in tumor volume and grade promoted extraprostatic spread more than nondiploidy, as shown by multivariate analysis. CONCLUSIONS: The incidence of a nondiploid cell population in a tumor focus in prostate cancer is essentially the same, at least for Americans and Japanese. DNA ploidy of a tumor cannot serve as a means of pathologic stage prediction in clinically resectable prostate cancers, contrary to many previous studies. Thus, DNA content analysis would be of no use for deciding on the treatment strategy of prostate cancer.

DNA, Neoplasm↗
PubMed1996

Significance of preoperative parameters for predicting tumor volume in nonpalpable prostate cancer.

Preoperative parameters were assessed for their usefulness in predicting tumor volume in 26 cases of nonpalpable prostate cancer. The number of positive biopsy cores was found to be the parameter which predicted most accurately tumor volume in surgical specimens. All 14 patients with multiple positive cores had an index tumor of 0.5 cm3 or more in radical prostatectomy specimens. Only six tumors with a single positive core were substantial. Three of the patients showed a serum level of prostate specific antigen (PSA) of 4.0 ng/ml or more. The pathological stage and prostatectomy Gleason sum could not be predicted accurately by this variable (P>0.05). To predict index tumor volumes of 1.0 cm3 or greater, stepwise logistic regression analysis was conducted, and on the basis of the results it was possible to single out multiple positive biopsies as the only significant variable. The number of positive biopsies appeared reliable for predicting tumor volume of surgical specimens in cases of nonpalpable disease. The presence of significant tumors despite "normal" levels of PSA warrants further investigation of variables that can predict such prostate cancers. An adequate model for predicting significant tumors in oriental male populations should be established using samples of larger size.

Biopsy, Needle↗
PubMed1996

Preoperative serum prostate-specific antigen, clinical stage and Gleason sum as basis for predicting final pathological stage in Japanese patients with prostate cancer.

By logistic regression analysis and log-likelihood ratio chi-square test, the usefulness of preoperative variables (prostate specific antigen [PSA], clinical stage and biopsy Gleason sum) for predicting the final pathological stage was assessed in 77 patients with clinically resectable prostate cancers. Pathologically, 32 (41.6%) had organ-confined disease. Extracapsular extension was found in 41 (53.2%), seminal vesicle involvement in 30 (39.0%), positive pelvic lymph nodes in 10 (13.0%) and a positive surgical margin in 27 (35.1%). Each preoperative variable was found to be significantly associated with the final pathological stage. Any combination of these variables was more predictive for extraprostatic disease, compared with each individual variable. Extraprostatic spread was found more frequently in patients with lower serum PSA in this Japanese elderly male population compared with North American males. These preoperative variables considered in combination may provide valuable information for management decisions related to prostate cancer. Serum PSA alone cannot reliably predict pathological stage on an individual basis except in patients with a PSA level of 20 ng/ml or greater. The high incidence of extraprostatic spread at intermediate PSA underscores the importance of selecting an ideal cutoff value for PSA-based screening in a Japanese male population.

Aged↗
PubMed1996

Development of a novel immunohistochemical staining technique (PLATESTAIN technique) based on the capillary action principle.

OBJECTIVE: To improve the complex manual staining methods used in immunohistochemistry, the authors invented a glass plate designed to achieve accurate immunoreaction using the capillary action principle. MATERIALS: This plate has slightly elevated edges and provides five narrow gaps between the reactive surfaces and glass slides. Each reactive surface is treated with a hydrophobic agent, to allow uniform antibody diffusion. RESULTS: Seventy-five cases of control tissues, benign neoplasms, and malignant neoplasms were immunohistochemically examined with this plate, and the staining intensity was compared with that of the conventional three-step streptavidin-biotin technique. Using this device and biotin-long spacer conjugated secondary antibody, even diffusion of antibodies and reagents and sensitive reactions could be achieved, thus making immunostaining easier and more accessible. The hydrophobic agent produced no unfavorable results. Also, the technique greatly reduced the amount of antibody, reagent, and chromogen solution required. Antigen retrieval by microwave heating of tissue sections and immunostaining of sex hormone receptors and cell proliferation markers were also successful. CONCLUSION: This technique provides a great technical improvement in immunohistochemistry and eliminates the health problems and environmental hazards associated with conventional techniques.

Antibodies↗
PubMed1996

[Membranous nephropathy in Japanese children].

Since 1973, 15 patients, consisting of 8 boys and 7 girls, were diagnosed as having membranous nephropathy (MN). The average age at detection was 8.2 years (2-14 years). The presenting symptom was edema in 1, pyrexia in 1 and upper respiratory infection in 1 case, in the all other cases, abnormal urinalysis was detected by the school or chance urinalysis. Surface antigen of hepatitis B virus (HBs) was positive in 6 patients and negative in 9. Anti-nuclear antibody (ANA) was positive in 3 and negative in 11. In one patient, ANA was not tested. One patient who was negative for ANA was diagnosed as having SLE 4 years later. At the last follow-up, 10 patients continued to have urinary abnormalities. Among these was one case positive for HBs antigen who went into end-stage renal failure. In the other 14 patients, the serum creatinine level was below 1.4 mg/dl. All patients showed a normal mesangium or mild mesangial proliferation. The patient diagnosed as having SLE. 4 years later showed mesangial deposits at the first renal biopsy. In our experience, most patients with MN were detected by the school or chance urinalysis and six of the these had positive HBs antigen. Lupus nephritis must be ruled out in making a diagnosis of idiopathic MN.

Adolescent↗
PubMed1995

Early detection of prostate cancer. Results of a prostate specific antigen-based detection program in Japan.

BACKGROUND: Prostate cancer increasingly is becoming a medical problem in Japan. To maximize the chance for cure, extensive effort is being made to detect prostate cancer while confined to the gland. METHODS: Determination was made of serum prostate specific antigen (PSA) in the early detection of prostate cancer in an Asian male population aged 55 years or older. Recommendation for biopsy was based solely on this parameter when its value exceeded 2.0 ng/ml in IMx immunoenzymetric assay. RESULTS: Of 1189 men, 150 (12.6%) had elevated values. The proportion of males with serum PSA greater than 4.0 ng/ml was only 3.4%. Of the 99 males who underwent ultrasound-guided biopsies, 16 cancers were detected, a cancer detection rate of 1.3%. Most of these (81.3%) were clinically localized cancers. Seven patients with cancer had serum PSA levels below 4.0 ng/ml including 5 less than 3.0 ng/ml. These tumors would have been overlooked if the conventional cutoff levels of 4.0 ng/ml had been applied. Radical prostatectomy was conducted on 13 patients. All had histologic features of clinically significant cancer and 69.2% were pathologically confined within the gland. CONCLUSIONS: Elderly Asian males appear to have lower serum PSA than their Western counterparts. The optimal cutoff of serum PSA for early detection should be examined further in Asian male populations. Differences in the incidence of prostate cancer between ethnic groups may have been overestimated in previous studies owing in part to unawareness by the physician and general public. Though the frequent use of more sophisticated diagnostic modalities will likely disclose greater numbers of prostate cancers in Japan, whether early detection reduces mortality by minimizing risk of death from cancer remains a point to be determined.

Aged↗
PubMed1995

Expression of bcl-2 oncogene protein is prevalent in small cell lung carcinomas.

To investigate the frequency of bcl-2 oncogene protein expression in small cell lung carcinoma (SCLC), immunohistochemical staining with a mouse-anti-human monoclonal antibody, bcl-2/124, was carried out on 60 formalin-fixed, paraffin-embedded SCLC samples obtained from surgical biopsy, and autopsy cases. bcl-2 protein was detected in 54 out of the 60 SCLCs. In 47 cases, more than half of the tumour cells stained positively. The staining intensity of the tumour cells was comparable to that of infiltrating lymphocytes in 37 cases, but varied from area to area and even from cell to cell. Negative data in six cases were found to be due to unsuitable fixation or embedding procedures rather than the absence of the antigen. bcl-2 oncogene protein may thus be expressed in most if not all SCLCs. bcl-2 may have potential diagnostic and therapeutic importance in SCLCs and non-SCLCs. Previous cytogenetic and molecular genetic analyses indicate that SCLCs carry a number of chromosomal abnormalities and it would follow from the present results that the abnormal expression of bcl-2 may also play a role in the pathogenesis of SCLC, by increasing tumour mass through inhibition of apoptosis as previously proposed. The diagnostic, prognostic, and therapeutic implications of these findings should be studied in greater detail.

Carcinoma, Small Cell↗
PubMed1995

Effects of cyclosporin on serum hyaluronan levels in collagen arthritis.

Serum hyaluronan (HA) levels were measured in a rat model of collagen arthritis using a sandwich enzyme-linked immunosorbent assay. Values became elevated as the arthritis developed, correlating with its severity. Daily subcutaneous treatment with cyclosporin at the dose of 25 mg/kg per day for fourteen days completely prevented anti-type II collagen antibody production and the serum HA increase as well as development of collagen arthritis. HA in the blood may thus provide a good quantitative marker for joint disease in rat collagen arthritis with potential as a tool for evaluation of drug efficacy in this experimental model.

Animals↗
PubMed1995

Idiopathic membranoproliferative glomerulonephritis in Japanese children.

The course of idiopathic membranoproliferative glomerulonephritis (MPGN) in 41 Japanese children (21 boys, 20 girls) is reported. The mean follow-up period was 8 years, 9 months; 29 children with MPGN (71%) were identified by school urinary screening; 32 patients had type I MPGN, 2 type II and 7 type III; 10 patients were treated with multiple low-dose cocktail therapy (MLD), 8 with MLD followed by high-dose alternate-day (ALD) prednisolone and 21 with high-dose ALD prednisolone alone. In 1 patient, MPGN progressed to end-stage renal failure. The serum creatinine level in all of the remaining 40 patients was < or = 1.3 mg/dl at the last follow-up. Urinalysis was normal in 24 (59%). Of the 17 patients who still had urinary abnormalities, 4 had nephrotic syndrome. The incidence of remission of urinary abnormalities was highest in the patients treated with high-dose ALD prednisolone. Rebiopsy was performed in 33 patients, and revealed slight histological improvement in 11 (33%) patients, moderate improvement in 8 (24%), marked improvement in 5 (15%) and deterioration or no improvement in 9 patients (27%). Relatively few side effects of treatment were observed. The superior outcome of the MPGN patients in this compared with other studies may be the result of earlier detection and treatment.

Adolescent↗
PubMed1995

Assessment of sextant biopsy of the prostate for detecting cancer prior to therapy in patients clinically diagnosed as benign prostatic hyperplasia.

Pathological results and perioperative morbidity were compared in 199 patients who had undergone prostatectomy and/or biopsy in order to determine the extent to which systematic biopsy is effective for detecting prostate cancer prior to therapy in patients clinically diagnosed as having benign prostatic hyperplasia. Seventeen (8.5%) cancers were detected in 199 patients following surgery and/or biopsy. Digitally-guided biopsy as a means of detecting prostate cancer was found to be just as effective as ultrasound-guided biopsy. Seven (12.5%) cancers were detected in 56 patients who had undergone biopsy and transurethral resection. Preprostatectomy biopsy detected only two of three patients with stage T1b disease. All four stage T1a and one stage T1b failed to be diagnosed. Of 90 patients who had biopsy prior to surgery other than TURP, seven (7.8%) cancers were found. Four of these were advanced. The incidence of postoperative fever > 38.0 degrees C and duration of postoperative pyuria did not differ significantly between groups with or without biopsy. Preoperative biopsy did not contribute to perioperative morbidity. Tumors detected by systematic biopsy are usually large and clinically significant. Positive biopsy results are often diagnostic, but the pathological features of a tumor together with clinical parameters should be considered to reduce the chance of overdiagnosing an insignificant tumor. Sextant biopsy would be most applicable to patients scheduled for any type of therapy other than TURP especially in those with markedly elevated serum PSA levels. This procedure may be beneficial particularly for younger patients with long life expectancy who will benefit from definitive therapy.

Aged↗
PubMed1995

[Clinicopathological study of nonpalpable and nonvisible (stage T1c) prostate cancer].

Clinical and pathologic characteristics of stage T1c disease (nonpalpable and nonvisible cancer) was studied retrospectively in men who underwent radical prostatectomy in order to better understand this disease entity. Findings in stage T1c disease (16 patients) were directly compared with those in stage T2b disease (11 patients). No significant difference was observed between these groups with regard to age, preoperative serum prostatic acid phosphatase level, prostatic weight, numbers of tumor foci, total tumor volume, volume of index cancer and tumor grade (p > 0.05). Preoperative prostate specific antigen concentration was significantly lower in stage T1c group (p < 0.05). Substantially larger number of patients with stage T1c disease had pathologically organ confined disease when compared with T2b group (86.7% versus 45.5%, p < 0.05). Seventy-five percent (12/16) of stage T1c and 90.9% (10/11) of stage T2b disease were considered clinically significant. Most of stage T1c disease is organ confined and clinically significant. Clinical and pathologic features of these tumors are similar to those in T2b disease. Twenty-five percent of stage T1c disease, however, are small and thus may potentially be overtreated. Enhanced detection of prostate cancer achieved with modern technology can lead to undesirable treatment of clinically insignificant tumors. Preoperative diagnostic modalities which can reliably distinguish groups of tumor with different biological potential are needed to overcome this contradiction.

Acid Phosphatase↗
PubMed1995

[Early detection of prostate cancer-results of a prostate specific antigen-based detection program at a "multiphasic screening"].

Determination was made of serum PSA in the early detection of prostate cancer in a population of 1,227 men aged 55 years or older who visited a "human dock". "Human dock" is a unique health examination facility open to public in Japan. Recommendation for biopsy was made based solely on this parameter when its value exceeded 2.0 ng/ml in IMx immunoenzymetric assay (Dinabot Co.). Of these, 162 (13.2%) had elevated values. The proportion of males with serum PSA greater than 4.0 ng/ml was only 3.6%. Of the 109 males who underwent ultrasound guided biopsies, 17 cancers were detected, the cancer detection rate thus being 1.4%. Most of these cases (82.4%) were clinically localized cancers. Eight patients with cancer had serum PSA levels below 4.0 ng/ml including 6 less than 3.0 ng/ml. Radical prostatectomy was conducted on 14 patients. All had histologic features of clinically significant cancer and 64.3% were pathologically confined. Oriental elderly males appear to have lower serum PSA than western counterparts. The optimal cutoff of serum PSA for early detection should be examined further in oriental male populations. Differences in the incidence of prostate cancer between ethnic groups may have been overestimated in previous studies owing in part to unawareness by the physician and general public. Though the application of PSA for early detection will likely disclose greater numbers of prostate cancers in Japan, whether early detection reduces mortality by minimizing risk of death from cancer remains a point to be clarified.

Aged↗
PubMed1994

Clinico-pathological study of the role of infarct expansion in patients with cardiac rupture following acute myocardial infarction.

The purpose of this study was to clarify whether the infarct expansion with cardiac rupture following acute myocardial infarction pathomorphologically differed from expansion without rupture. Eighteen autopsied patients with rupture were classified into acute phase (time between the onset of myocardial infarction and death < or = 36 h) and subacute phase (> 36 h). These patients were compared with 25 patients with no rupture using new parameters of expansion: radius index, cavity index, expansion area index and thinning-dilatation index of the left ventricle. In the acute phase, each parameter was significantly higher in the ruptured group than in the non-ruptured group (radius index: 0.49 +/- 0.28 vs 0.14 +/- 0.16, p < 0.005, cavity index: 0.21 +/- 0.09 vs 0.08 +/- 0.06, p < 0.005, expansion area index: 0.75 +/- 0.25 vs 0.34 +/- 0.23, p < 0.001, thinning-dilatation index: 2.89 +/- 1.31 vs 1.53 +/- 0.52, p < 0.001). However, in the subacute phase there were no differences in these parameters between the two groups. These data suggest that in the acute phase, but not the subacute phase, the degree of expansion and the proportion of expansion to infarcted area are associated with rupture.

Aged↗
PubMed1994

[Usefulness and limitation of digital rectal examination and imaging studies in staging prostate cancer].

The diagnostic usefulness of digital rectal examination (DRE), transrectal ultrasonography (TRUS), magnetic resonance imaging (MRI) and computed tomography (CT) was compared in the differentiation of stage B from stage C prostate cancer. Eighteen patients who had undergone radical retropubic prostatectomy were included in this study. Overall, the positive predictive values (PPV) for detecting extraprostatic disease (extracapsular extension, seminal vesicle invasion) were 100% for DRE, 88.9% for TRUS and 80.0% for MRI, respectively. Corresponding figures for accuracy in detecting extraprostatic spread were 55.6%, 66.7% and 61.1%, respectively. The PPV and accuracy for detecting extraprostatic disease in 13 patients with localized cancer (< stage B) were 75.0%, 53.8% for TRUS and 66.7%, 53.8% for MRI, respectively. Both of these examinations appeared to be superior to DRE alone. The PPV and accuracy increased when findings on TRUS and MRI coincided. Computed tomography was less accurate than MRI in diagnosing nodal involvement because of the higher incidence of false positives. Further efforts should be focused on enhancing preoperative diagnostic precision in staging prostate cancer because of the limited usefulness of the current imaging techniques. Development of more reliable diagnostic modalities or designing ideal combination of these studies are desperately needed.

Aged↗
PubMed1994

The significance of tubulointerstitial nephritis in IgA nephritis.

The occurrence of significant tubulointerstitial nephritis (TIN) was observed in 6 (18.3%) of 32 patients with IgA nephritis registered in 1991. T lymphocytes and macrophages in the interstitium were seen to invade the tubulus through injured tubular basement membrane (TBM), then were seen in the intercellular spaces of tubular cells which showed degeneration, single cell necrosis or detachment. Thus some tubular components were seen destroyed and had disappeared resulting in interstitial fibrosis, and others showed a regeneration process forming a renewed TBM on the innerside of the original TBM. However the recurrence of cellular inflammation was again observed in these regenerated tubuli. Thus the progression of nephron loss by TIN was seen to be independent of the glomerular changes and TIN is considered to be one of the important factors in predicting the prognosis of IgA nephritis.

Adolescent↗
PubMed1994

[Recurrent meningioma with malignant transformation: a case which changed from meningothelial type to papillary type].

We report here a case with meningioma showing malignant transformation in its course of multiple recurrences. A 59-year-old woman developed a right-sided hemiparesis in June, 1982 and CT scan disclosed a parasagittal well-enhanced mass. The tumor was subtotally removed (Simpson grade III) by an operation in September, 1982. Histological findings of the tumor were consistent with a meningothelial meningioma but showed no malignant features, such as high cellularity, necrotic foci, high mitotic rate, or nuclear pleomorphism. However, the tumor did invade the underlying cerebral cortex. In August, 1986, a recurrent tumor was detected by CT scan and was removed (Simpson grade III). The tumor tissue at the second operation showed the same histological features as the first specimen. In September, 1990, the patient developed multiple intracranial recurrences. There were three tumor nodules, all of which were removed. Histologically, significant histological differences between the second and the third operative specimens were found. In the last tumor tissue, one nodule showed a papillary pattern. In the other tumor nodules, each tumor cell had proliferated separately instead of adhering to other tumor cells to form a syncytium. This histological pattern was consistent with an epithelial meningioma described by Cushing and Eisenhardt in 1938. The papillary portion of the tumor was stained with monoclonal antibody Ki-67 in frozen section. The labelling index was 9.7%, which was as high as malignant meningioma. Electron microscopic examination of the papillary portion of the tumor showed that the tumor cells had irregular nuclei, interdigitations between the adjacent plasma membranes and a few ill-developed desmosomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗