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Biomedical subjects

S Koga

Publications and source records attributed to S Koga.

538 records · Page 30Linked to original sources
PubMedDate not supplied

The effect of angiotensin II on blood flow in tumours during localized hyperthermia.

The selective enhancement of drug delivery to tumours is an important factor in the effectiveness of thermochemotherapy as well as in standard normothermal chemotherapy. We have attempted to clarify experimentally using AH 100B tumour-bearing rats whether or not a selective increase in blood flow in tumours can be produced under specific conditions of local hyperthermia by administration of angiotensin (AGT II). AGT II (2 micrograms/kg/min) produced an elevation of blood pressure (ca. 150 mm Hg) when local hyperthermia, at 41, 43, and 45 degrees C, was induced. Furthermore, at 41 and 43 degrees C a selective increase in blood flow in tumours resulted from the AGT II-induced hypertension. By contrast, a decrease in blood flow was observed at 45 degrees C both in tumour and in muscle. These results indicate that AGT II-induced hypertension and the resultant selective increase in drug delivery to tumours during the initial phase of heating may result in an augmentation of the anticancer effects of thermochemotherapy.

Angiotensin II↗
PubMedDate not supplied

Brachytherapy of a choroidal melanoma using radioactive gold grains: a long-term follow-up study.

PURPOSE: We used radioactive gold grains to treat a patient with choroidal malignant melanoma. Radioactive sources were placed into surgically constructed scleral pockets. The patient was followed up for six years after therapy to assess changes in the tumor, recurrence, and side effects. METHODS AND MATERIALS: A male patient presented with malignant melanoma arising from the choroidal membrane of the posterior pole of the left eyeball. We placed radioactive gold grains into surgically constructed scleral pockets adjacent to the tumor, arranged in a plane based on the Manchester's method. The patient was followed up for six years after treatment. RESULTS: The radiation dose was 120 Gy at the apex of the tumor, which slowly became smaller and completely disappeared at one year and 10 months after treatment. Tumor recurrence was not observed. Radiation dose at the ipsilateral lens was 280 cGy. Side effects associated with therapy were a decrease in visual acuity secondary to retinal degeneration and atrophy, but his vision was correctable with suitable glasses. In addition, the visual field of the left eye was also restricted. Mild cataracts also developed in the ipsilateral eye after treatment. CONCLUSION: Although this therapeutic method is technically difficult compared with other methods, it permits the tumor to be treated without loss of the eye. This may significantly improve the patient's quality of life.

Adult↗
PubMedDate not supplied

Subcutaneous administration of interferon alpha and gamma in patients with metastatic renal cell carcinoma.

BACKGROUND: Renal cell carcinoma (RCC) is relatively resistant to both chemotherapy and radiotherapy. Response and survival of treatment with Interferon-alpha (IFN-alpha) and Interferon-gamma (IFN-gamma) were evaluated in patients with metastatic RCC. PATIENTS AND METHODS: Thirty-one patients with confirmed RCC were included in this study. Fifteen of 31 patients received injection of IFN-alpha and IFN-gamma three times a week. IFN-gamma was infused subcutaneously by microinfusion pump. Sixteen received IFN-alpha alone more than three times a week. RESULTS: The overall response rate was 20.0% in the IFN-alpha and IFN-gamma group, and 12.5% in the IFN-alpha alone group. Long lasting stabilization of the disease (more than; 12 months) was seen in 92.3% of CR, PR or SD in the IFN-alpha and IFN-gamma group, as compared with 71.4% in the IFN-alpha alone group. Both groups differed significantly in survival rate from the first treatment with IFN (p < 0.05). CONCLUSIONS: A long lasting stabilization of the disease can be expected in patients who were treated with our regimen of IFN-alpha and IFN-gamma.

Adult↗
PubMedDate not supplied

Breast cancer metastatic to the kidney.

We report a case of renal tumor secondary to a breast cancer occurring 16 years after radical mastectomy. This is the sixth report case of renal metastasis from breast cancer of a 51-year-old woman. Percutaneous biopsy of the renal tumor confirmed the diagnosis during the follow-up. The patient was treated with chemotherapy and is alive 8 months after diagnosis. Previously, cases like our case showed long interval from mastectomy to diagnosis of metastasis.

Breast Neoplasms↗
PubMedDate not supplied

The role of surgery in renal cell carcinoma with solitary metachronous metastasis to contralateral adrenal gland.

We report a case of renal cell carcinoma with solitary metachronous metastasis to contralateral adrenal gland occurring 9 months after radical nephrectomy. The patient was treated with a contralateral adrenalectomy and is alive for 87 months. The literature was reviewed and 5-year survival of solitary metachronous metastasis to contralateral adrenal gland was 60%. Follow-up duration of our case was the longest in the literature. It is suggested that the solitary contralateral adrenal gland metastasis of renal cell carcinoma should be resected since there is no effective treatment of metastatic renal cell carcinoma. Good prognosis may be then and the good be expected.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Renal cell carcinoma metastatic to the skin.

BACKGROUND: Cutaneous metastases from renal cell carcinoma are rarely diagnosed during life. We reviewed the cases of our institute and from the Japanese literature and analyzed them to define the clinical features. PATIENTS AND METHODS: Six patients with cutaneous metastases from renal cell carcinoma were treated in our institute. Clinical data and follow-up information of these patients were reviewed. RESULTS: The skin metastatic lesions were found before the renal lesion was discovered in one case and they were found after the diagnosis had been established in 5. Four patients presented with solitary cutaneous metastasis at the time of diagnosis of the skin metastatic lesion. Five patients had other sites of metastases such as the lung, liver and bone at the time of diagnosis of cutaneous metastases. Five patients died of renal cell carcinoma at mean 23.8 months after presenting with cutaneous metastases. CONCLUSION: Our 6 cases bring the total reported in the Japanese literature to 75 cases. The results of these 75 cases revealed that the duration from the time of diagnosis of renal cell carcinoma to detection of the cutaneous metastasis was relatively long but the prognosis of patients with these metastatic skin lesions was poor. Cutaneous metastases from renal cell carcinoma were regarded as a late manifestation of the disease.

Aged↗
PubMedDate not supplied

Results of combined-modality therapy for primary and secondary malignant lymphoma of the central nervous system (CNS).

PURPOSE: We consider that whatever the vital prognosis of secondary CNS lymphoma (SCNSL), its local control is as serious as that of primary CNS lymphoma (PCNSL). In this study, both the treatment outcomes and local control of patients with SCNSL and PCNSL were compared, with the aim of improving the treatment of SCNSL. MATERIALS AND METHODS: This study included 11 patients with PCNSL and 14 with SCNSL treated from January 1984 to October 1997. PCNSL patients underwent partial tumor resection and received systemic chemotherapy. All SCNSL patients received systemic chemotherapy, and eight also received intrathecal anticancer drug infusion. Nine PCNSL patients and 11 SCNSL patients underwent whole-brain radiation therapy with 4-MV photons. Among the SCNSL patients, three patients underwent localized-brain irradiation and two patients also received whole-spine irradiation. RESULTS: Five-year survival rates were 34% for PCNSL and 33% for SCNSL. In SCNSL, survival times after CNS involvement were very short, irrespective of treatment. One-year local control rates after CNS irradiation were 38% for PCNSL and 14% for SCNSL. Recurrence was mainly found in the cranial region, in seven of 11 PCNSL patients and 10 of 14 SCNSL patients. CONCLUSIONS: Patients with SCNSL had a poor prognosis, and local control in them was more problematic than in patients with PCNSL. It is necessary to develop new combined modality therapy for patients with SCNSL,including the participation of a radiation oncologist, before the disease becomes progressive.

Adult↗
PubMedDate not supplied

FADD gene therapy using the human telomerase catalytic subunit (hTERT) gene promoter to restrict induction of apoptosis to tumors in vitro and in vivo.

Gene transfer vectors will dramatically increase the safety and effectiveness of cancer gene therapy, if they could restrict expression of the therapeutic products to the target tumors. To realize such a tumor-targeting system, telomerase is one of the most promising candidates. It is because telomerase activity is detected in the vast majority of tumors, but not in most normal cells. Activation of telomerase is tightly regulated at the transcriptional level of the telomerase catalytic subunit (hTERT). Therefore, the use of the hTERT promoter-driven vector system could restrict the expression of therapeutic products to telomerase-positive tumors. In this study, we constructed the expression vector of FADD gene with death domain afforded by the hTERT promoter (hTERT/FADD) and investigated its effect on tumors in vitro and in vivo. Transient transfection with the hTERT/FADD construct induced apoptosis in telomerase-positive tumor cells of wide range. In contrast, normal fibroblast cells without telomerase did not undergo apoptosis following the hTERT/FADD transfer. Furthermore, the growth of subcutaneous tumors in nude mice was significantly suppressed by the intratumoral injection of the hTERT/FADD construct (every day for one week) compared to the control (P<0.0005). The findings described here indicate the high potentiality of a novel telomerase-specific gene therapy of tumors with telomerase.

Adaptor Proteins, Signal Transducing↗
PubMedDate not supplied

Minor changes in regional cerebral blood flow revealed by the early distribution of I-123 IMP in brain.

To evaluate the early distribution of I-123 IMP in the brain, 10 dynamic images were obtained in the first 10 minutes after injection using a ring-type SPECT system with a high-sensitivity collimator. In cases of chronic carotid occlusion without brain CT abnormalities, areas of low perfusion were more clearly demonstrated in dynamic images than in static images obtained beginning 20 minutes after injection and continuing for 15 minutes using a high-resolution collimator. In cases of hyperperfusion following infarct or surgery, there was a difference between dynamic and static images in the visualization of hyperemic lesions. The distribution of I-123 IMP in the brain changes gradually, even in the early period after injection, and evaluation of early accumulation is useful for the detection of minor changes in regional cerebral blood flow.

Aged↗
PubMedDate not supplied

Relationship between the cytologic characteristics of intraperitoneal free cancer cells and the prognosis in patients with gastric cancer.

The presence of free cancer cells in the peritoneal cavity of 387 patients with gastric cancer was analyzed using specimens obtained by intraoperative lavage of the pouch of Douglas. If cancer cells were found in the specimen, the case was classified with respect to the number and arrangement (clustered or isolated) of the cancer cells found. Study of the relationship between the histologic type of cancer and the presence of free cancer cells showed that poorly differentiated adenocarcinomas and signet ring-cell carcinomas were associated with a higher incidence of free cancer cells than were other types of cancer. The relationships between the characteristics of the free cancer cells and the postoperative survival rate were also studied. Patients whose free cancer cells were present in clusters were associated with a more favorable prognosis than were those with no such clusters. Patients with small numbers of free cancer cells survived longer than did those with large numbers of free cancer cells.

Adenocarcinoma↗
PubMedDate not supplied

Calcification of the vertebral artery.

A series of 3,648 computed tomographic (CT) scans was reviewed to determine the incidence of intracranial vertebral artery calcification. Calcification was identified in one or both vertebral arteries in 3.4% and was more frequent in the higher age groups. Skull radiographs demonstrated vertebral artery calcification in only one of 48 patients in whom CT studies showed it. A high correlation was observed between vertebral artery calcification on CT and vertebral artery stenosis on cerebral angiography.

Adult↗
PubMedDate not supplied

Viability of intraperitoneal free cancer cells in patients with gastric cancer.

The viability and morphologic changes of intraperitoneal free cancer cells in advanced gastric cancer patients were examined by Giemsa and enzymologic staining and by tritiated thymidine uptake. Although many free cancer cells in the pouch of Douglas showed moderate degeneration, viable, morphologically intact cells were noted, leading to the possibility of their implantation and proliferation in the peritoneum. Serosal cancer cells showed a high degree of viability. In patients undergoing gastric cancer surgery, the viability of free cancer cells was markedly decreased by a single intraoperative administration of 10 mg of mitomycin C (MMC) to the pouch of Douglas, suggesting that this may represent an effective means of preventing peritoneal dissemination.

Adult↗