Biomedical subjects

Yutaka Takazawa

Publications and source records attributed to Yutaka Takazawa.

11 recordsLinked to original sources

PubMed2006

Combined phospho-Akt and PTEN expressions associated with post-treatment hysterectomy after conservative progestin therapy in complex atypical hyperplasia and stage Ia, G1 adenocarcinoma of the endometrium.

Young patients with complex atypical hyperplasia (CAH) or stage Ia, G1 adenocarcinoma (IaG1) of the endometrium, who desire to preserve fertility, can select the conservative therapy by oral progestin, medroxyprogesterone acetate (MPA). However, conservative treatments involve potential risks of progression and recurrence. In an attempt to find out molecular markers for sensitivity to MPA, we performed immunohistochemical analysis of PTEN, phospho-Akt, p53, ER and PgR in MPA-treated 31 cases with CAH or IaG1. Eleven of 12 cases (92%) with CAH and 15 of 19 cases (79%) with IaG1 demonstrated an initial complete response, while five patients underwent hysterectomy due to no response. Four of 11 responders (36%) with CAH and five of 15 responders (33%) with IaG1 later developed relapse. Five of nine patients (56%) with CAH and three of 11 patients (27%) with IaG1 became pregnant after infertility treatment. Immunohistochemical analysis revealed that phospho-Akt expression was significantly decreased by MPA administration (p=0.002). Furthermore, combination of two factors, weak phosho-Akt or PTEN-null expression, was found to be significantly associated with receiving hysterectomy (p=0.04), while each factor showed a trend without statistical significance (p=0.07 and 0.2, respectively). Strong expression of both ER and PgR significantly correlated with successful pregnancy after infertility treatment following complete response to MPA (p=0.02). Our observations in vivo suggest that anti-tumor action of MPA may be mediated by dephosphorylation of Akt, and that immunohistochemical evaluation of phospho-Akt and PTEN may be able to predict the outcome of MPA therapy.

Adenocarcinoma↗

PubMed2006

Interobserver variability in histologic recognition, interpretation of KIT immunostaining, and determining MIB-1 labeling indices in gastrointestinal stromal tumors and other spindle cell tumors of the gastrointestinal tract.

The authors studied the concordance among seven pathologists for the histologic diagnosis, interpretation of KIT immunostaining, and determining MIB-1 labeling indices (LI) in 80 adult patients with primary spindle cell tumors, mainly of the gastrointestinal tract, mesentery, retroperitoneum, and pelvis, based on the review of tissue sections using an immunohistochemical panel of antibodies for KIT/CD117, CD34, desmin, smooth muscle actin (SMA), and S-100 protein. Tumors included 30 gastrointestinal stromal tumors (GISTs), 10 leiomyomas, 10 leiomyosarcomas, 10 schwannomas, 10 solitary fibrous tumors, and 10 desmoid-type fibromatoses. The overall concordance with the original diagnosis of each histologic type was 97.9%, the kappa value ranging from 0.95 to 1.00 (mean 0.97), indicating a perfect agreement. The overall interlaboratory concordance with the original interpretation of KIT immunostaining was 91.3%, the kappa value ranging from 0.77 to 0.90 (mean 0.86). The overall interlaboratory concordance with the original interpretation of KIT immunostaining was 91.9%, the kappa value ranging from 0.72 to 0.93 (mean 0.85). The overall concordance for determining MIB-1 LI was 90% with the original evaluation, and the overall kappa value ranged from 0.62 to 0.86 (mean 0.77). These results indicate that it is possible to reliably diagnose GIST and other spindle cell tumors of the gastrointestinal tract with the use of an immunohistochemical panel of antibodies for KIT, CD34, desmin, SMA, and S-100 protein. Although there is clearly unavoidable inter-observer and interlaboratory variability in the interpretation of KIT immunostained sections and interobserver variability in the determination of MIB-1 LI, the concordance between observes is very acceptable, and in most instances such variability can be eliminated by careful reviewing of the hematoxylin and eosin and immunostained sections.

Adult↗

PubMed2006

Tubulovillous adenoma developing after urinary reconstruction using ileal segments.

A case of tubulovillous adenoma arising in an augmented bladder is described. Ureteroileal substitution and ileocystoplasty was performed when the patient was 18 years old. She noticed gross hematuria 44 years after the surgery. Cystoscopy revealed a non-papillary multiple tumor at the site of ileovesical anastomosis and transurethral resection biopsy was performed. Histopathological examination revealed a tubulovillous adenoma. A tubulovillous adenoma developing at the augmented bladder is rare. To our knowledge, this is the second case in which a tubulovillous adenoma developed in an augmented bladder.

Adenoma, Villous↗

PubMed2005

Gastrointestinal stromal tumors of neurofibromatosis type I (von Recklinghausen's disease).

Gastrointestinal stromal tumor (GIST), as well as the hyperplastic lesions of intestinal neural tissue and its supporting structures, is a gastrointestinal complication of type 1 neurofibromatosis (NF1) (von Recklinghausen's disease). In the present study, we analyzed the histologic and immunohistochemical features, and the c-kit and PDGFRA gene mutations of 36 GISTs derived from 9 NF1 patients. Distinctively, multiple GISTs arose preferentially in the small intestine. The histologic features of NF1-associated GISTs are almost similar to those of non-NF1 GISTs, but characteristically most of the NF1-associated GISTs contained skeinoid fibers. Thirty-three GISTs (92%) showed immunoreactivity for KIT, and 23 tumors (64%) showed diffuse or mosaic-like immunoreactivity for S-100 protein. Hyperplasic lesions, which may be the hyperplasia of interstitial cells of Cajal, were observed around some GISTs. Exons 9, 11, 13, and 17 of the c-kit gene and exons 12 and 18 of the PDGFRA gene were amplified and directly sequenced. Point mutations of c-kit gene or PDGFRA gene were identified only in three (8%) and two (6%) tumors, respectively. NF1-associated GISTs, showing the dual differentiation of interstitial cells of Cajal and Schwann cells, develop in close association with the myenteric nerve structure of gastrointestinal tract of NF1 patients. The point mutations of c-kit and PDGFRA gene may play a limited role in the tumorigenesis of NF1-associated GISTs.

Adult↗

PubMed2004

Hemophagocytic syndrome caused by fulminant ulcerative colitis and cytomegalovirus infection: report of a case.

We report a case of hemophagocytic syndrome that developed in a 35-year-old, Japanese male with fulminant ulcerative colitis. The patient underwent an emergency operation, consisting of subtotal colectomy, ileostomy with rectal preservation (suprapubic mucous fistula). After the operation, peripheral blood counts showed progressive pancytopenia and bone marrow aspirate smears revealed hypocellular bone marrow with an increase in histiocytes, indicating hemophagocytic syndrome. Viral studies (serum antibody titer and antigenemia of cytomegalovirus) revealed systemic cytomegalovirus infection. The patient was diagnosed with virus-associated hemophagocytic syndrome and was successfully treated with antiviral therapy consisting of intravenous ganciclovir, gamma globulin, and granulocyte-colony stimulating factor.

Adult↗

PubMed2004

Myxoid epithelioid gastrointestinal stromal tumor (GIST) with mast cell infiltrations: a subtype of GIST with mutations of platelet-derived growth factor receptor alpha gene.

We analyzed 30 gastrointestinal stromal tumors (GISTs) that were immunohistochemically weak or negative for KIT. Histologically, all 30 GISTs consisted of epithelioid tumor cells in at least a part of the tumor. The tumor cells showed different morphologies and arranged themselves in different histological patterns. In 20 of the 30 GISTs, round or oval epithelioid tumor cells often showed a less cohesive pattern of growth and showed eosinophilic cytoplasm and peripherally placed nuclei with myxoid stroma, whereas in the remaining 10 cases, tumor cells were arranged in a more cohesive pattern without myxoid stroma. The former type of tumors is called myxoid epithelioid GISTs in this study. Subsequent mutational analyses showed that the platelet-derived growth factor receptor alpha (PDGFRA) gene mutations in exon 12 or exon 18 were identified in 20 (66.7%) of the 30 GISTs, and especially in 18 (90%) of the 20 myxoid epithelioid GISTs. Moreover, 17 (85%) of the 20 myxoid epithelioid GISTs were accompanied by mast cell infiltrations within the tumor nodules. In the remaining cases, 2 (6.7%) of the 30 GISTs had c-kit gene mutations in exon 11, and no mutation was found in 8 (26.7%) of 30 GISTs. None of the patients with myxoid epithelioid GISTs died of disease. These results suggest that myxoid epithelioid GISTs are a distinct subtype of GISTs that are closely correlated with the PDGFRA gene mutation and that recognition of such histological characteristics should be helpful for molecular subclassification of GISTs that are important for molecular targeting therapy by imatinib mesylate (STI571).

Adult↗

PubMed2003

Early valvular obliteration of cryopreserved aortic valve allograft.

This report describes a 60-year-old male patient who developed early valvular obliteration of a cryopreserved aortic valve allograft with associated severe valvular leakage. The patient had previously undergone two operations for aortic valve insufficiency resulting from infective endocarditis, and prosthetic valve endocarditis: aortic valve replacement with a mechanical prosthesis was done 4 years ago, and two years later aortic root replacement with a cryopreserved allograft was performed. Perforation through the non-coronary cusp of the aortic allograft was found, and valve replacement was achieved using a mechanical prosthesis. The intraoperative findings, histological, immunological, and bacteriological studies of the resected cusps demonstrated negative for infection and rejection, therefore, the valvular perforation might have been caused by an injury or degeneration during management of the homologous graft. The patient showed neither aortic regurgitation on echocardiography nor recurrence of endocarditis 10 months after surgery.

Aortic Valve↗

PubMed2003

Diabetic mastopathy in an advanced elderly woman with insulin-dependent type 2 diabetes mellitus.

Diabetic mastopathy is an unusual stromal fibrotic lesion, but typically occurs in long-standing insulin dependent and younger diabetic patients. We report a case of diabetic mastopathy in an older diabetic patient. The patient was a 76-year-old woman with a history of type 2 diabetes mellitus for 13 years and 3 years of insulin treatment. She developed a 3 cm, hard, mobile nodule in the left breast. Mammography revealed a dense mass. Ultrasonography showed an irregular-shaped hypoechoic lesion with an unclear boundary and acoustic shadowing. Since fine needle aspiration biopsy delivered insufficient material and core needle biopsy did not yield any specific findings for diagnosis, clinically diabetic mastopathy was the prime suspect but breast cancer could be completely ruled out. Surgical excision was thus performed and diabetic mastopathy was confirmed pathologically. We report on this rare case of diabetic mastopathy in a 76 year-old type 2 diabetic patient.

Aged↗

PubMed2003

Ovarian choriocarcinoma arising from partial mole as evidenced by deoxyribonucleic acid microsatellite analysis.

BACKGROUND: Recent developments in genetic analysis allow determination of the origin of choriocarcinoma (ie, gestational or nongestational), which helps determine the strategy for clinical treatment of the disease. CASE: We present a case of ovarian choriocarcinoma forming a huge ovarian mass 40 days after the patient's last menstrual period. Deoxyribonucleic acid microsatellite analysis of the tumor revealed that it contained a single maternal and two paternal alleles at several independent loci, consistent with the tumor resulting from ovarian pregnancy of a partial hydatidiform mole. CONCLUSION: This is the first description of an ovarian pregnancy of a partial hydatidiform mole-derived ovarian choriocarcinoma.

Adult↗

PubMed2003

CD44 variant 6 in endometrioid carcinoma of the uterus: its expression in the adenocarcinoma component is an independent prognostic marker.

The expression of variant isoforms of CD44 (CD44v) correlates with the metastatic potential of various carcinomas. In endometrial cancer, however, the significance of CD44v-expression as a prognostic indicator has not been fully investigated, nor has it been compared with that of p53, estrogen receptor or Ki67. Surgical material consisted of 14 atypical endometrial hyperplasias (AEH) and 163 endometrial carcinomas (EC). Expression of CD44s, v3 and v6 in carcinoma tissue, and other prognostic markers were immunohistochemically evaluated. The expression in the squamous differentiation was strictly excluded for the evaluation of immunohistochemistry, because the significance was different from that in the adenocarcinoma component. CD44s was frequently expressed in AEH and EC. On the other hand, CD44v3- and v6-positivities were rare or nonexistent in AEH, but were observed in 8 and 35% of EC, respectively. CD44v3-expression correlated significantly with histologic grade and lymph node metastasis. However, there was no correlation between CD44v6 expression and any clinicopathologic factor, nor were other prognostic markers expressed. Univariate analysis revealed that each CD44 was a prognostic determinant in the patients with EC. However, employing multivariate analysis, there were only three independent factors: p53 overexpression, CD44v6 expression and myometrial invasion. CD44v6 expression in the adenocarcinoma component may directly affect the behavior of carcinoma and the prognosis of patients with EC.

Adenocarcinoma↗

PubMedDate not supplied

Case of optic nerve involvement in metastasis of a gastrointestinal stromal tumor.

BACKGROUND: The gastrointestinal stromal tumor (GIST) belongs to the leiomyosarcoma or leiomyoma group, and metastasis of leiomyosarcoma to the orbit is extremely rare. The most common sign of the metastasis of leiomyosarcoma to the orbit is proptosis; the primary lesion is usually found in skin or soft tissue. CASE: A 60-year-old man, who had a history of multiple metastases of GIST, suffered sudden unilateral blindness. OBSERVATIONS: His history and computed tomographic scans suggested that the lesion was a metastasis of GIST to the cavernous sinus around the root of the optic nerve. CONCLUSION: To the best of our knowledge, this is the first case of metastasis of GIST to the orbit.

Fatal Outcome↗