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Biomedical subjects

N Kawano

Publications and source records attributed to N Kawano.

At least 37 records · Page 2Linked to original sources
PubMed1999

Endoscopic resection for submucosally invasive colorectal cancer: is it feasible?

BACKGROUND: Recent advances in colonoscopy have resulted in an increasing number of endoscopic resections of colorectal neoplasms. However, endoscopic resection of submucosal invasive cancer remains a controversial issue. METHODS: The subjects for this study were the surgically treated patients with submucosal invasive colorectal cancer. These patients were classified into two groups: those with versus those without preoperative endoscopic resection. Clinicopathologic features and prognosis were compared and analyzed. RESULTS: Fifty patients underwent surgery for submucosally invasive colorectal cancer. Numbers of patients with and without preoperative endoscopic resection were 22 and 28, respectively. In 36.4% of the patients, endoscopic resections were incomplete. Two patients in whom the preoperative endoscopic resections had revealed a positive cancer margin, had nodal metastasis. One of these patients also developed hepatic metastasis. Endoscopic findings such as diameter and shape were not indicative of either lymphatic or vascular invasion. There were no morbidities or mortalities associated with endoscopic resection or surgery. CONCLUSIONS: Preoperative endoscopic resection for colorectal submucosal cancer is feasible, provided the resection is complete. The indications for surgical treatment should be determined after pathologic examination.

Case-Control Studies↗
PubMed1999

Cerebral germinoma with syncytiotrophoblastic giant cells: feasibility of predicting prognosis using the serum hCG level.

As the biological behaviour of germinoma with syncytiotrophoblastic giant cells (STGC) is not well established, the present study was undertaken to ascertain the prognostic significance of serum hCG level in affected patients. Of a total of 23 cases studied, 12 patients were regarded as pure germinomas and 11 were germinomas with STGC. All but one of the former demonstrated an excellent outcome. The exception developed subarachnoid metastases, but the tumour disappeared on radiation therapy and the patient is enjoying a normal social life 13 years after the initial treatment. With the germinoma complicated by STGC, 3 cases showed local recurrence which were followed by a poor outcome. Their pretreatment hCG levels were 15.0, 26.0 and 29.6 mIU/ml respectively. The study showed a tendency, in germinomas with STGC, for a positive association between serum hCG, and the likelihood of a poor outcome. Germinomas with STGC and serum hCG levels higher than 15 mIU/ml thus have a high recurrence rate, and more aggressive treatment is indicated for the affected patients.

Adolescent↗
PubMed1999

Basement membrane patterns, gelatinase A and tissue inhibitor of metalloproteinase-2 expressions, and stromal fibrosis during the development of peripheral lung adenocarcinoma.

To clarify the process and mechanisms of the development and progression of peripheral lung adenocarcinoma, we investigated the relationships among the patterns of basement membrane (BM), stromal fibrosis, and the expressions of gelatinase A and tissue inhibitor of metalloproteinases-2 (TIMP-2) in 33 lesions of atypical alveolar cell hyperplasia (AAH) and 48 lesions of lung adenocarcinoma, including 24 lesions of bronchioloalveolar carcinoma (BAC). We found that the architecture of alveolar BM was intact in all 33 AAH lesions and 11 nonsclerosing BAC lesions that formed no central scar, suggesting that these lesions are early-stage intraepithelial neoplasia. The preexistent BM of the lung was disrupted, and the BM components around the neoplastic glands were disrupted or absent in the area of the central scar of some sclerosing BAC lesions with collapse fibrosis alone (2 of 4) and in those of all of the adenocarcinoma lesions associated with desmoplastic stromal fibrosis (nine sclerosing BAC and 24 non-BAC tumors). These results suggested that, in lung adenocarcinomas, destruction of the BM was correlated with the formation of a central scar, particularly with desmoplasia. It is likely that adenocarcinomas with a central scar are advanced and invasive cancers potentially having metastatic activity. The expression of gelatinase A and TIMP-2 was associated with central scar formation as well as with destruction of the BM components. Both the neoplastic and stromal cells expressed gelatinase A and TIMP-2 and probably play a role in tumor cell invasion.

Adenocarcinoma↗
PubMed1999

Cerebellar clear cell ependymoma mimicking hemangioblastoma: its clinical and pathological features.

BACKGROUND: As the clinical and pathological significance of cerebellar clear cell ependymoma (CCE) has not been recognized in the past, eight cases of cerebellar CCEs were studied. METHODS: Subjects were six men and two women, and their ages ranged from 23 to 64 years old. Their neuroradiological, operative, and pathological features were reviewed. RESULTS: The tumors frequently showed high vascularity on angiography and marked enhancement on computerized tomography. Grossly, six tumors exhibited a "cyst with mural nodule" and two were mostly solid containing small cysts. At operation, the tumor nodules were dark red in color and the cysts contained xanthochromic fluid. Microscopically, all tumors displayed mostly clear round cells and abundant blood vessels. Although they commonly lacked the characteristic features of ependymomas, immunostaining and electron microscopy confirmed their ependymal origin. CONCLUSIONS: The results indicate that cerebellar CCEs closely mimic hemangioblastoma both clinically and pathologically, which suggests CCE should be considered in the differential diagnosis of vascular tumors of the cerebellum. Some diagnostic clues to differentiate CCE from hemangioblastoma are discussed.

Adult↗
PubMed1999

Neurocysticercosis case with a single cyst in the brain showing dramatic drop in specific antibody titers within 1 year after curative surgical resection.

We report on one Japanese case subject with neurocysticercosis (NCC) who had a single cyst in the brain and had undergone curative surgical resection. Pathological examination revealed that it was a cysticercus of Taenia solium. Serological examination of the pair serum samples just before and 1 year after surgery revealed that antibody responses against the glycoproteins, highly specific to NCC and detected in the serum sample just before surgery by both immunoblot and ELISA became negative within 1 year after the surgery. It is, therefore, strongly suggested that this case had a single cysticercus in his whole body and the presence of a single cysticercus was sufficient to evoke antibody responses against it.

Animals↗
PubMed1999

Leptomeningeal melanomatosis with multiple cutaneous pigmented nevi: tumor cell proliferation and malignant transformation in an autopsy case.

We experienced a rare case of leptomeningeal melanomatosis. The proliferative activity and nuclear accumulation of p53 in this tumor were examined, since the relationship between this tumor type and growth has not yet been elucidated. A 33-year-old Japanese man was shown to have leptomeningeal melanomatosis with multiple cutaneous pigmented nevi. The autopsy findings showed the presence not only of benign diffuse melanosis of the leptomeninges but also of leptomeningeal melanomatosis in the subarachnoid space and brain parenchyma. In the brain parenchyma, the direct invasion of tumor cells from the subarachnoid space and Virchow-Robin spaces filled with melanoma cells were observed. Multiple hemorrhagic areas invaded by melanoma cells were also present. Immunohistochemical staining with a monoclonal antibody to melanoma cells showed positivity in the tumor cells. Proliferation analysis using the MIB-1 antibody demonstrated that the labeling index of tumor cells invading brain parenchyma (2.54%) was higher than that in other lesions of the inner (0.89%) and outer layer (0.76%) of the subarachnoid space. Nuclear accumulation of p53 protein was rarely seen in the tumor cells. We reported a case of leptomeningeal melanomatosis. Higher proliferative activity was found in invading cells of the brain parenchyma. Malignant transformation of the tumor did not appear to be associated with p53 gene mutation.

Adult↗
PubMed1999

Significance of growth hormone-releasing hormone receptor mRNA in non-neoplastic pituitary and pituitary adenomas: a study by RT-PCR and in situ hybridization.

This study examined the expression of human growth hormone-releasing hormone receptor (GHRH-R) mRNA in both non-neoplastic pituitary tissues and pituitary adenomas by reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization (ISH). RT-PCR analysis showed that all of the non-neoplastic pituitaries and all GH-producing adenomas, one prolactinoma and one third of the non-functioning adenomas expressed GHRH-R mRNA. ISH demonstrated that all of GH-producing adenomas and two prolactinomas expressed GHRH-R mRNA. The expression of GHRH-R mRNA in GH-producing adenomas was greater than that in the other adenomas by RT-PCR and ISH. GHRH-R mRNA detected by ISH was observed only in GH cells from the pituitary gland of a young girl. In pituitary adenomas, a diffuse signal was observed in the cytoplasm of all of the GH-producing adenomas and in two prolactinomas. Expression of GHRH-R mRNA was not seen in normal prolactin cells, or in any adenomas other than GH-producing adenomas and a few prolactinomas. These results suggest that GHRH-R mRNA plays a role mainly in the function of GH-producing adenomas but may also play a role in function of some prolactinomas.

Adenoma↗
PubMed1999

Desmoplastic small round-cell tumor of the paratesticular region: report of an adult case with demonstration of EWS and WT1 gene fusion using paraffin-embedded tissue.

Desmoplastic small round-cell tumor typically occurs in the abdomen of young men, but it can also develop at other anatomic sites and in older people, presenting greater diagnostic difficulties. We report a case of this tumor arising from the paratesticular region in a 43-year-old man. The tumor showed histologic, immunohistochemical, and ultrastructural evidence of multilineage differentiation, including epithelial, mesenchymal, and neuronal features. In addition, the presence of an EWS and WT1 chimeric messenger RNA was demonstrated by the reverse transcriptase-polymerase chain reaction using an EWS exon 7 primer and WT1 exon 8 and exon 9 primers, which revealed single polymerase chain reaction products with a junction of EWS exon 7 to WT1 exon 8. Our study demonstrates that desmoplastic small round-cell tumors of the paratesticular region share not only morphologic but also molecular genetic features with those of the abdomen and that reverse transcriptase-polymerase chain reaction analysis using paraffin sections is useful for a conclusive diagnosis.

Abdominal Neoplasms↗
PubMed1998

Appendico-ileo-vesical fistula.

Appendico-vesical fistula is a rare condition. In total, 109 cases, most secondary to appendicitis, have been reported in the English-language literature. We report the first case, to our knowledge, of appendico-ileo-vesical fistula secondary to appendiceal diverticulitis. An enterovesical fistula was diagnosed by urine culture, cystoscopy, and computed tomography. The locations of enteric opening sites were demonstrated by barium enema and colonoscopy. Ileocecal resection and fistulectomy with primary reconstruction were performed. We believe that accurate pre- and intra-operative diagnosis is essential for cure. This case demonstrates the importance of barium enema and colonoscopic examinations in the diagnosis and treatment of complicated enterovesical fistula.

Adult↗
PubMed1998

Long-term functional outcome of suprasellar germinomas: usefulness and limitations of radiotherapy.

We investigated the long-term functional outcome of patients with suprasellar germinoma after radiotherapy to determine the usefulness and limitations of radiotherapy for these tumors. From among 54 cases of intracranial germ cell tumor at Kitasato University Hospital, 12 patients with suprasellar germinoma who were treated with radiotherapy but not chemotherapy retrospectively investigated for mental, hormonal and visual functions. The follow-up period ranged from 63 to 262 months (mean, 161.1 months). The mortality rate was zero and there was no recurrence of tumors. However, three patients treated with local irradiation alone showed metastasis to the ventricles or spinal cord. With regard to mental function, 50% of the patients showed remarkably low mental function after radiotherapy. With regard to pituitary hormonal function, deficiency of ADH, GH, ACTH, and TSH was documented in 75%, 41.7%, 16.7% and 8.3% of the patients, respectively, before radiotherapy. Prolactin was elevated in 50% of the patients. After radiotherapy, 91.7% needed hormone replacement. With regard to visual function, most patients showed an improvement or no change after radiotherapy. In conclusion, radiotherapy for suprasellar germinomas gave long-time survival. However, such radiotherapy may cause mental and pituitary hormonal dysfunction. Our results show that while radiotherapy is useful for treating suprasellar germinomas, its dose have some limitations.

Adolescent↗
PubMed1998

Preoperative superselective embolization of skull-base meningiomas: indications and limitations.

We evaluated the clinical significance of preoperative superselective embolization for skull-base meningiomas. The subjects consisted of 20 patients with skull-base meningiomas, and were classified into a preoperative embolized group and a non-embolized group. The volume of blood transfused during the operation, the length of the operative procedure and the neurological outcome were compared between the two groups. The results showed that, in tumors smaller than 6 cm, the blood lost during the operation was significantly less in the embolized group. In tumors larger than 6 cm, there was not difference in blood lost, perhaps because larger meningiomas tend to have tiny blood vessels that are unsuitable for preoperative embolization. There was no difference in the length of the operation between the two groups. The embolized group tended to show a better clinical outcome than the non-embolized group.

Adult↗
PubMed1998

Proton magnetic resonance spectroscopy of the brain in three cases of Rett syndrome: comparison with autism and normal controls.

Rett syndrome (RS) is a clinically defined disorder characterized by autistic behavior, and cognitive and motor skill loss early in life. We performed 1H-MRS of the brain in 3 cases of RS in comparison with in autism and controls. The older patient with RS demonstrated decreased N-acetylaspartate (NAA)/choline (Cho) and NAA/creatine (Cr) ratios when compared with the autism and control groups, whereas the younger patients did not demonstrate these decreased metabolite ratios. The Cho/Cr ratio did not differ among Rett syndrome, autism and controls. Since the clinical stage did not differ among the 3 cases of RS, it was suggested that NAA was decreased with increasing age and was not related with the clinical stage of RS. The NAA/Cho, NAA/Cr and Cho/Cr ratios did not differ between autism and controls. The present data suggest that there may be a secondary degenerative process of late onset in RS, which pathophysiologically differs from autism.

Adolescent↗
PubMed1998

Juvenile symptomatic Rathke's cleft cyst--case report.

A 14-year-old girl presented with a rare symptomatic Rathke's cleft cyst manifesting as diabetes insipidus and growth retardation. Neuroimaging demonstrated the suprasellar cyst. Computed tomography showed the cyst as an isodense area with enhancement, and magnetic resonance imaging showed an hyperintense area on both T1- and T2-weighted images. Histological examination showed the cyst was consistent with Rathke's cleft cyst. Symptomatic Rathke's cleft cysts usually occur in middle-aged adults. Juvenile cases tend to present with diabetes insipidus, and the cyst content may include more mucopolysaccharides or hemosiderin degradation products.

Adolescent↗
PubMed1997

Stomach-preserving gastric bypass for unresectable pancreatic cancer.

From 1992 to 1995, we treated 25 patients who had unresectable pancreatic cancer with a stomach-preserving gastric bypass (SPGB). After as much of the stomach as possible was preserved, it was bypassed to the jejunum by end-to-side anastomosis. During the same period, five patients underwent other types of bypasses while 47 similar patients did not undergo gastric bypass. Although the mean operative time for SPGB was significantly longer than for other types of bypass, the mean intraoperative blood loss was similar. Operative morbidity with SPGB was 28%, and there were no operative deaths. In patients undergoing SPGB, the incidence of delayed gastric emptying was high (24%), but the comfort index (ratio of duration of good palliation to duration of survival) exceeded 50% when metastases were either regional or systemic but limited. The comfort index of patients undergoing other types of bypass or not undergoing bypass was less than 40%. However, the patients with extensive systemic metastases survived less than 100 days and the comfort index was less than 30% for all treatment groups. Our results thus suggest that SPGB is safe and effective for patients with either regional metastases or limited systemic metastases.

Cholestasis↗