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F Akiyama

Publications and source records attributed to F Akiyama.

At least 37 records · Page 2Linked to original sources
PubMed2000

In vitro evaluation of Er:YAG laser scaling of subgingival calculus in comparison with ultrasonic scaling.

The purpose of the present study was to evaluate the effectiveness of Er:YAG laser scaling and the morphological and histological changes of the laser-scaled root surface in comparison with the effectiveness and root surface changes produced by conventional ultrasonic scaling. Fifty-three periodontally involved human extracted teeth with a band of subgingival calculus were used. The teeth were divided randomly into 2 groups for laser scaling and ultrasonic scaling. Laser irradiation was performed at an energy output of 40 mJ/pulse and 10 pulses/s under water spray, with the probe tip contacted obliquely to the root surface. Ultrasonic scaling was performed at a clinically standard power setting. The time required for scaling, the scaled area and the temperature changes were determined using both methods of treatment. The features of the scaled surfaces were examined by histological and scanning electron microscope (s.e.m.) observations. The Er:YAG laser provided subgingival calculus removal on a level equivalent to that provided by the ultrasonic scaler, without major thermal elevation. Macroscopically, the laser-treated root surface was somewhat rougher than or similar to the ultrasonically scaled root. However, the efficiency of the laser scaling was lower than that of the ultrasonic scaling. In addition, histological examination revealed a thin deeply stained zone on the lased root surface, and s.e.m. analysis revealed a characteristic microroughness on the lased surface. The laser scaling provided a level of calculus removal that was similar to that provided by the ultrasonic scaling. However, the Er:YAG laser produced superficial, structural and thermal microchanges on the root cementum.

Dental Calculus↗
PubMed2000

A quantitative model using mean and standard deviation for evaluation of interobserver agreement in nuclear atypia scoring of breast carcinomas in a protocol study.

A quantitative model was devised for the purpose of evaluating interobserver agreement in the judgment of the nuclear atypia score of cancer cells in protocol studies. In this model, the mean nuclear atypia score (mu) among observers was considered to approximate the 'true' nuclear atypia score of the tumor, and with an identical mu the strength of interobserver agreement was evaluated by the difference between the ideal standard deviation (sigma) and the observed sigma in the slide conference session. This model was applied to the data of a total of 216 invasive ductal carcinomas acquired at eight slide conference sessions held for the standardization of nuclear atypia scoring and monitoring of interobserver agreement level for enrolled cases in a surgical adjuvant protocol on breast cancer. Compared with conventional percentage interobserver agreement and kappa statistics, the present model, named the lambda model, was more sensitive in detecting the improvement of interobserver agreement in nuclear atypia scoring with repetition of slide conference sessions. The lambda model was particularly effective for evaluating the session which included many intermediate cases with a score between 1 and 2 or between 2 and 3. Percentage interobserver agreement and kappa statistics could estimate the agreement irrespective of the number of observers, but the agreement tended to be underestimated when these intermediate cases were in the majority. The present method was considered to be complementary to conventional methods for evaluating interobserver agreement of cancer histology in protocol studies.

Breast Neoplasms↗
PubMed2000

Evaluation of the interobserver agreement in the number of mitotic figures of breast carcinoma as simulation of quality monitoring in the Japan National Surgical Adjuvant Study of Breast Cancer (NSAS-BC) protocol.

In the National Surgical Adjuvant Study for Breast Cancer (NSAS-BC), node-negative breast cancers were divided into higher- and lower-risk groups according to the histopathological nuclear grade given at individual collaborating hospitals, and the higher-risk group was entered into a randomized protocol of adjuvant therapy. Because the nuclear grade was the composite of nuclear atypia and mitotic counts, maintenance of interobserver agreement in mitotic counts was indispensable for the success of the protocol study. Fourteen pathologists participating in the protocol judged whether or not 20 photomicrographs suspected of showing mitotic cancer-cell figures truly showed mitoses. After standardizing the counting method, these pathologists counted the number of mitotic figures per 10 high-power fields of hematoxylin-eosin-stained main-tissue sections of 20 tumors. Areas where mitotic counts were considered to be the most frequent by each pathologist were compared for these tumors. For the judgment of whether the photomicrograph indicated mitosis, the level of interobserver agreement was moderate (kappa = 0.569). In the observations of 20 tumors, interobserver agreement level of mitotic counts was moderate (kappa = 0.506), that of nuclear atypia scoring was fair (kappa = 0.265), and that of nuclear grading was substantial (kappa = 0.633). The counted area was almost the same among the observers in 9 tumors, split into two areas in 6, and dispersed in 5. Concordance in judgment was achieved in 7 of the first 9 and in all of the third 5, but only in one of the second 6. The cause of discordance was mostly derived from tumor heterogeneity and the difference in the site where mitoses were counted. Interobserver agreement level was considered to be satisfactory, and it was expected that the case entry would be performed appropriately in the protocol study. The selection of the counting area was confirmed to be important for the acquisition of high-level agreement level in mitotic counts.

Breast Neoplasms↗
PubMed2000

[Myeloperoxidase-antineutrophil cytoplasmic antibody positive alveolar hemorrhage during propylthiouracil therapy for hyperthyroidism].

A 62-year-old woman had been treated with propylthiouracil(PTU) for hyperthyroidism. Because bloody sputum, dyspnea, and severe hypoxemia developed, the patient was admitted to our hospital. Chest X-ray and chest computed tomographic (CT) films disclosed diffuse infiltrative shadows in both lung fields. Bronchoalveolar lavage revealed abundant hemosiderin-laden macrophages. Alveolar hemorrhage associated with myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) positive vasculitis syndrome was diagnosed because of the high serum level of MPO-ANCA. After the initiation of steroid therapy and termination of PTU, the infiltrative shadows in both lung fields disappeared, PaO2 improved, and MPO-ANCA decreased. There have been some reports of MPO-ANCA positive vasculitis syndrome developing during PTU therapy, but most were concerned with renal disease. We concluded that PTU and similar agents should be given consideration as one of the possible causes of MPO-ANCA-induced alveolar hemorrhage.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2000

Allelic loss at 1p34-36 predicts poor prognosis in node-negative breast cancer.

Allelic losses of specific chromosomal regions in the DNA of tumor cells, which imply loss of tumor suppressor genes normally resident at those loci, may become useful postoperative prognostic indicators for breast cancers that have not yet metastasized to lymph nodes. To examine whether specific allelic losses might correlate with postoperative disease-free survival, we tested tumors from a cohort of 228 node-negative breast cancer patients for allelic losses at 18 microsatellite loci chosen to represent either a known tumor suppressor gene or a region where genetic alterations are frequent in breast tumors. We followed the patients clinically for 5 years or until death (if patient death occurred before completion of 5 years of follow-up). Patients whose tumors had lost an allele at 1p34-36 bore significantly higher risks of postoperative recurrence than those whose tumors retained both alleles of the markers in that region [the 5-year recurrence rate was 15% among patients with losses versus 2% among patients with retention (P = 0.001)]. Multivariate analysis demonstrated that allelic loss at 1p34-36 was an independent postoperative predictor of shorter disease-free survival (hazard ratio, 5.8; P = 0.0117). Thus, allelic losses at 1p34-36 in a tumor might have a potential to serve as a negative prognostic indicator to guide postoperative management of breast cancer patients, especially in the selection of high-risk women who will benefit from adjuvant chemotherapy and endocrine therapy.

Adult↗
PubMed1999

Correlation of Allelic Loss with Poor Postoperative Survival in Breast Cancer.

BACKGROUND: Allelic losses of tumor suppressor genes or the chromosomal regions harboring them in the DNA of tumor cells may become useful postoperative prognostic indicators. METHODS: To examine whether specific allelic losses correlate with postoperative survival in a five-year prospective follow-up, we tested tumors from a cohort of 504 breast cancer patients for allelic loss of 18 microsatellite markers representing either known tumor suppressor genes or regions where genetic alterations are frequent in breast tumors. RESULTS: Patients with allelic loss at 1p34, 3p25, 8p22, 13q12, 17p13.3, or 17q21.1 had a significantly higher risks of postoperative mortality compared withthose whose tumors retained both alleles at those loci (at 1p34, the 5-year mortality rate was 23% among patients with loss vs 10% with retention, p 0.0100; at 3p25, 22% vs 9%, p =0.0014; at 8p22, 24% vs 7%, p =0.0177; at 13q12, 19%vs 8%, p=0.0093; at 17p13.3, 19% vs 9%, p=0.0078; and at 17q21.1, 17% vs 10%, p =0.0475). CONCLUSION: Allelic losses at these loci can serve as negative prognostic indicators to guide post-operative management, especially in the selection of thosewho will benefit from intensive adjuvant therapies.

Journal Article↗
PubMed1999

Frequent multiplication of chromosome 1q in non-invasive and papillotubular carcinoma of the breast.

Carcinogenesis is considered to be a multistep process that may involve cumulative genetic alterations; one of these mechanisms, gain of chromosomal material, has the potential to activate tumor-promoting genes in breast carcinogenesis. Using 12 polymorphic microsatellite markers on the long arm of chromosome 1 (1q), we examined 130 sporadic breast carcinomas for abnormalities in the copy numbers of these loci in tumor cells using a differential PCR method. We also sought correlations between alterations on 1q and several clinicopathological parameters. At every locus examined, a 2-3-fold increase in copy number of an allele in tumor material was observed in one third of the tumors (46 of 130, 35%), indicating 'multiplication' of 1q. This multiplication involved the entire long arm in majority of those tumors (43 cases, 93%). The multiplication of 1q was observed more frequently in non-invasive ductal and papillotubular histological types than in solid-tubular and scirrhous types (13/25, 52% vs. 27/90, 30%) (P = 0.041). The predominant chromosomal alterations on 1q in breast carcinomas are found to be multiplications rather than losses. The multiplication represents polysomy of the entire region of 1q, and may confer a growth advantage during development and/or progression of non-invasive ductal and papillotubular histologic types of breast carcinomas.

Adenocarcinoma, Papillary↗
PubMed1999

Frequent multiplication of chromosomal region 8q24.1 associated with aggressive histologic types of breast cancers.

Carcinogenesis is considered to be a multi-step process that may involve cumulative genetic alterations. One such alteration, gain of chromosomal material, has the potential for activating genes that promote carcinogenesis in breast tissues. Using 14 polymorphic microsatellite markers on the long arm of chromosome 8 (8q), we examined 142 sporadic breast cancers for abnormalities in the copy-numbers of these loci. At each locus examined, a 2- to 3-fold increase in intensities of bands representing single alleles was observed in 57 (40%) of the tumors, indicating that 'multiplication' of the DNA sequence had occurred on 8q. A 16-cM region on 8q24.1 was commonly multiplied among the tumors with partial multiplications. Multiplication on 8q24.1 was observed more frequently in invasive solid-tubular or scirrhous tumors (48/92, 52%) than in less aggressive histologic types (7/25, 28%, P = 0.031). Thus, multiplication of tumor-promoting gene(s) located on 8q24.1 may play a role in the development and/or progression of a substantial proportion of primary breast cancers, particularly those of the invasive histology.

Alleles↗
PubMed1999

Surgical Margin Status as a Cause of Local Failure after Breast Conserving Therapy.

BACKGROUND: To elucidate the cause of in-breast recurrence after breast conserving surgery, we analyzed the characteristics of resected specimens histopathologically, especially the surgical margin status. MATERIALS AND METHODS: 1) Pathological surgical margin positivity was reevaluated in terms of the distance from the resected surgical margin by pathologists from seven institutions in 486 cases with complete stepwise pathological examination. 2) We reviewed pathological specimens including surgical margins from 30 patients with in-breast recurrence for whom serial sections of resected primary breast cancer specimens were available and made comparisons of the time to in-breast recurrence. RESULTS: Cancer cells at the surgical margin were present at a rate of 4.1% on the surface and 15.2% within 5 mm on the areolar side of the surgical margin. Histopathologically, the reasons for local recurrence after breast conserving therapy included a positive surgical margin (21/30), lymphatic permeation (4/30), and others (5/30). The last category included cases with an inadequate margin diagnosis because of a biopsy scar. Disease-free intervals for the patients without postoperative radiotherapy decreased as the volume of cancer cell nests in thesurgical margin increased (P=0.06). On the other hand, this trend was not observed in the group with postoperative radiotherapy. CONCLUSION: Adequate materials are essential for accurate evaluation of surgical margin status. Quantitative evaluation of surgical margin status, apart fromwhether or not radiotherapy was performed, is important for estimating the riskand disease-free period to in-breast recurrence.

Journal Article↗
PubMed1999

Localization of a tumor suppressor gene associated with the progression of human breast carcinoma within a 1-cM interval of 8p22-p23.1.

BACKGROUND: Frequent allelic losses on the short arm of chromosome 8 in several types of human cancers, and deletion maps of this region in tumor DNAs, have suggested that 8p harbors one or more genes that are important for suppressing tumorigenesis in the tissues in question. METHODS: To define the locations of potential tumor suppressor genes involved in breast carcinoma, the authors examined 144 primary breast carcinomas for loss of heterozygosity at 18 highly polymorphic microsatellite loci on 8p. They also sought correlations between allelic loss on 8p and several clinicopathologic parameters. RESULTS: Allelic loss was observed in 74 of the 144 sporadic breast carcinomas examined. Whereas more than half of the informative tumors showed loss of an allele at every locus on the short arm, 32 showed partial or interstitial deletions. Deletion mapping in this panel of tumors identified two distinct commonly deleted regions, one in a 1-cM interval flanked by D8S511 and D8S1991 at 8p22-p23.1, and the other in a 16-cM interval flanked by D8S136 and D8S1477 at 8p22-p21. Allelic losses in both of these regions were observed more frequently in tumors of the solid-tubular or scirrhous type than in less aggressive histologic types. Furthermore, allelic loss in either region occurred more frequently in larger and infiltrative tumors (T1 < T2 < T3). CONCLUSIONS: The association of allelic losses on 8p with advanced tumor stage and aggressive histologic type implies that loss or inactivation of one of at least two putative tumor suppressor genes on 8p may contribute to the progression of breast carcinoma.

Breast Neoplasms↗
PubMed1999

Utility of the monoclonal antibody HIK1083 in the diagnosis of adenoma malignum of the uterine cervix.

OBJECTIVES: The aim of this study was to qualify a staining technique for the diagnosis of adenoma malignum. METHODS: The gastric mucin expression of adenoma malignum, ordinary endocervical adenocarcinoma, and normal cervical glands was immunohistochemically compared using the monoclonal antibody HIK1083. RESULTS: The three categories were clearly distinguished, with 90% (9/10) of cases with positive adenoma malignum, 30% (3/10) of cases with weakly positive ordinary cervical adenocarcinoma, and no (0/10) cases of positive normal cervical glands. CONCLUSIONS: This preliminary report indicates that the use of HIK1083 is valuable in the diagnosis of adenoma malignum.

Adenoma↗
PubMed1999

The location of positive nodes partly influences the prognostic value of the number of positive nodes in breast cancer patients.

BACKGROUND: The aim was to determine whether the number of positive lymph nodes or the location of lymph node metastasis (location number) would permit a more accurate prediction of prognoses. METHODS: We compared the survival rates of 3922 patients with primary breast cancer in relation to the location number and the number of positive lymph nodes. Survival rates were calculated by the Kaplan-Meier method and analyzed using the log rank test. RESULTS: Within the n1 alpha group, the presence of one or two positive nodes was associated with significantly better survival than the presence of three positive nodes. These groups should therefore be distinguished. Within the n1 beta group, there was no significant difference in survival between patients with four and those with seven or more positive nodes. Comparisons of n1 beta and n2 patients after subgrouping by the number of positive nodes (4-9 and 10 or more) revealed a significantly poorer prognosis in the n2 group. CONCLUSIONS: When the prognosis of breast cancer is considered from the viewpoint of lymph node metastasis, the location number as described in the General Rules is an excellent classification. However, we should be aware of possible differences in the prognosis depending on the number of positive nodes, as this is masked by the location number.

Adult↗
PubMed1999

The efficacy and limitations of repeated slide conferences for improving interobserver agreement when judging nuclear atypia of breast cancer. The Japan National Surgical Adjuvant Study of Breast Cancer (NSAS-BC) Pathology Section.

BACKGROUND: The pathology section of the Japan National Surgical Adjuvant Study of Breast Cancer protocol study was set up to establish histological criteria for assessing high-risk node-negative breast cancers and standardize the subjective criteria used by collaborating pathologists for nuclear grading of cancers. METHODS: In order to standardize the nuclear atypia criteria, five slide conferences were held. A total of 57 observers assigned nuclear atypia scores to 119 breast carcinomas that were presented using a slide projector or a TV monitor and discussed their histological findings. The percentage interobserver agreements per tumor and per conference and kappa value per conference were estimated and compared among the conferences. The percentage intraobserver reproducibility per tumor between the last two conferences was compared with the percentage interobserver agreement for 20 tumors. The kappa value was also calculated for each of 27 observers to evaluate scoring reproducibility. RESULTS: The percentage interobserver agreement per conference was constant (75-78%) throughout the five meetings and the rate of tumors with > 80% agreement per tumor became higher in later conferences. The kappa value was 0.42, 0.25, 0.42, 0.51 and 0.50 for the first, second, third, fourth and fifth conferences, respectively. The tumors with a lower percentage interobserver agreement also had a lower percentage intraobserver reproducibility and such scoring variations were attributed to the intermediate nature of the degree of tumor atypia. In 26 of 27 observers, intraobserver agreement for 20 tumors was estimated from the kappa value to range from moderate to almost perfect. CONCLUSION: We concluded that the repeated slide conferences conducted by the pathology section were an effective means of standardizing the subjective histopathological criteria used to assess tumors. However, the achievement of a good scoring agreement would be difficult for tumors with an intermediate degree of atypia.

Breast Neoplasms↗
PubMed1999

Monitoring of interobserver agreement in nuclear atypia scoring of node-negative breast carcinomas judged at individual collaborating hospitals in the National Surgical Adjuvant Study of Breast Cancer (NSAS-BC) protocol.

BACKGROUND: In the NSAS-BC protocol, the nuclear atypia and mitotic counts are to be judged by pathologists at each participating hospital for assessing high-risk node-negative breast cancers. Therefore, maintenance of interobserver agreement in diagnosis at a higher level is mandatory during the period of patient entry. METHODS: Individual collaborating pathologists originally evaluated the histological eligibility of 107 cases. Three panel pathologists determined consensus diagnoses and 29-37 collaborating pathologists determined modal diagnoses of these cases at three slide conference sessions. The original diagnoses were compared with the consensus and modal diagnoses to estimate the percentage of erroneous judgments. RESULTS: The agreement rate in histological type and nuclear atypia score was 69% (74/107) between the original and consensus diagnoses, 76% (81/107) between the original and modal diagnoses and 86% (92/107) between the consensus and modal diagnoses. The strength of interobserver agreement at the slide conference sessions was moderate (0.447-0.535) by kappa statistics. The original, consensus and modal diagnoses were concordant in 71 cases (66%), but were discordant in 36. Of 35 invasive ductal carcinomas with discordant diagnoses, the discordance arose from the intermediate tumor nature in 15, multiple factors in 13 and erroneous diagnosis in seven (6.5%), if the characteristics of the tumor were judged from the percentage interobserver agreement per tumor at the slide conferences. CONCLUSION: Nuclear atypia scoring given at individual hospitals on case entry was almost reproducible among the pathologists. Continuous efforts are needed to improve interobserver agreement and to decrease erroneous diagnosis for protocol eligibility.

Breast Neoplasms↗
PubMed1999

Allelic loss at 1p34, 13q12, 17p13.3, and 17q21.1 correlates with poor postoperative prognosis in breast cancer.

Allelic losses of tumor suppressor genes (TSGs), or the chromosomal regions harboring them, in tumor DNA may become useful postoperative prognostic indicators. To examine whether specific allelic losses might correlate with postoperative survival in a 5-year prospective follow-up, we tested tumors from a cohort of 264 breast cancer patients for allelic losses of 18 microsatellite markers representing either a known TSG or a region where genetic alterations are frequent in breast tumors. Patients whose tumors had lost an allele at 1p34, 13q12, 17p13.3, or 17q21.1 had significantly higher risks of postoperative mortality than those whose tumors retained both alleles at those loci (at 1p34, a 5-year mortality rate of 29% among patients with losses vs. 7% with retentions, P = 0. 0008; at 13q12, 31% vs. 10%, P = 0.0062; at 17p13.3, 24% vs. 13%, P = 0.026; and at 17q21.1, 31% vs. 13%, P = 0.0047). Furthermore, combined losses at 13q12 and 17p13.3 increased the predicted postoperative mortality risks by a factor of 9.6 (5-year mortality rate of 42% vs. 5% with retentions, P = 0.0001), and combined losses at 1p34 and 17p13.3 raised the predicted postoperative mortality risks by a factor of 8.6 (27% vs. 3%, P = 0.0064). We conclude that allelic losses at these loci can serve as negative prognostic indicators to guide postoperative management of patients. Genes Chromosomes Cancer 26:134-141, 1999.

Adult↗
PubMed1998

The Current Status of the Treatment of Ductal Carcinoma In Situ of Japanese Women, Especially Breast Conserving Operation in Relation to the Surgical Margin and Short Term Outcome.

The indications for a breast conserving operation in the treatment of ductal carcinoma in situ (DCIS) of the breast with clinical manifestations other than mammographically detected calcifications are controversial. A positive surgical margin has been suggested to be an improtant risk factor for local recurrence after a breast conserving operation. We attempted to clarify the frequency of positive surgical margins when performing breast conserving operations for DCIS, identify the risk factors for positive margins, and also to evaluate the short-term outcome. Between 1988 and 1992, 5571 breast cancer cases were surgically treated at the 7 institutions of the authors, of which 375 cases (6.7%) were histologically diagnosed as DCIS. The most frequent clinical manifestation was a tumor in 64% of the cases, followed by nipple discharge in 23% and calcification on mammography in 12%. Of these 375 cases, 242 cases were analyzed. Sixty-six cases had undergone a breast conserving operation. Axillary dissection was not performed in 29 cases. The median follow up period was 61.4 months. The initial surgical margin was positive in 29% of the cases. The most significant factor for a positive surgical margin was young age fllowed by large tumor size. There were four cases with local recurrence. Three recurrences developed in the same quadrant. All four cases remain alive after total mastectomy. There were no cases with distant metastasis or axillary recurrence. Breast cancerving operation for DCIS have shown satisfactory results to date, and when clear surgical margins can be obtained, this procedure, without axillary dissection, should be considered even for patients with clinical manifestations other than mammographically detected calcifications.

Journal Article↗