Masanobu Takahashi

Tohoku University, Sendai-shi, Miyagi-ken, Japan

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Publications (8)18.1 Total impact

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    ABSTRACT: The requirement of central venous (CV) port implantation is increasing with the increase in the number of cancer patients and advancement in chemotherapy. In our division, medical oncologists have implanted all CV ports to save time and consultation costs to other departments. Recently, upper arm implantation has become the first choice as a safe and comfortable method in our unit. Here we report our experience and discuss the procedure and its potential advantages. All CV port implantations (n = 599) performed in our unit from January 2006 to December 2011 were analyzed. Procedural success and complication rates between subclavian and upper arm groups were compared. Both groups had similar patient characteristics. Upper arm CV port and subclavian implantations were equivalently successful and safe. Although we only retrospectively analyzed data from a single center, the upper arm group had a significantly lower overall postprocedural complication rate than the subclavian group. No pneumothorax risk, less risk of arterial puncture by ultrasound, feasibility of stopping potential arterial bleeding, and prevention of accidental arterial cannulation by targeting the characteristic solitary basilic vein were the identified advantages of upper arm CV port implantation. In addition to the aforementioned advantages, there is no risk of "pinch-off syndrome," possibly less patient fear of manipulation, no scars on the neck and chest, easier accessibility, and compatibility with the "peripherally inserted central catheter" technique. Upper arm implantation may benefit clinicians and patients with respect to safety and comfort. We also introduce our methods for upper arm CV port implantation with the videos.
    PLoS ONE 01/2014; 9(3):e91335. · 3.73 Impact Factor
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    ABSTRACT: Lynch syndrome, also known as hereditary non-polyposis colorectal cancer, characterized by predisposition to colorectal cancer and other associated cancers, is an autosomal-dominant disorder mainly caused by germline mutations in DNA mismatch repair (MMR) genes such as MLH1, MSH2, and MSH6. Some mutations that disrupt splice donor or acceptor sites cause aberrant mRNA splicing. These mutations are generally considered as pathogenic ones, however, it is sometimes uneasy to accurately predict their pathogenicity without functional assays, particularly when the mutation is a single nucleotide substitution. In this report, we describe a 25-year-old patient with Lynch syndrome who carries a germline variant in a splice donor site of the MLH1 gene (c.790 + 5 G > T), which was first detected among Asian populations. The immunohistochemical analysis revealed loss of MLH1 protein expression in the tumor. Our splicing assay confirmed that the intronic MLH1 variant actually caused aberrant splicing, supporting its pathogenic effect. Our data accumulate more information on the genotype-phenotype relationships in patients with Lynch syndrome.
    Familial Cancer 07/2012; · 1.94 Impact Factor
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    ABSTRACT: Oxaliplatin in combination with 5-fluorouracil (5-FU) and Leucovorin (FOLFOX) currently represents a valid approach for treating advanced colorectal cancer. In Japan, it is generally performed. Gastrointestinal, hematological and neurosensory toxicities are the most common. However, information concerning the pulmonary toxicity of this regimen is very limited. We report here two cases of interstitial lung disease occurring in association with the use of this combination chemotherapy. Reports of interstitial lung disease due to FOLFOX are infrequent, but could lead to severe complications. It is important to perform an X-ray examination regularly and detect symptoms early.
    Gan to kagaku ryoho. Cancer & chemotherapy 03/2009; 36(2):295-8.
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    ABSTRACT: Cancer of unknown primary site (CUP) is not a rare entity and accounts for 3-5% of all malignant neoplasias. CUPs are diagnosed with metastatic lesion so they are all in the advanced stage. Systemic chemotherapy is applied in many cases, but the ideal therapeutic strategy has not yet been determined. CUP shows much histological and therapeutic heterogeneity. Histologically, half of CUPs are adenocarcinoma and the rest are undifferentiated carcinomas. We analyzed the clinical and therapeutic characteristics 22 cases of CUP patients. Most CUP patients are found from lymph node swelling. There is no significant tendency as to the site of lymph node metastasis. Bone metastases are frequently encountered. It seems undifferentiated carcinomas are more responsive to chemotherapy. Chemo-sensitive patients are likely to have a longer life expectancy. In our experience all of the chemo-responsive cases are treated with platinum-based chemotherapy. Today several platinum-based combination chemotherapies are reported, but there is no large-scale randomized study. Because of its variety, individualized therapy may be ideal for CUP.
    Gan to kagaku ryoho. Cancer & chemotherapy 09/2007; 34(8):1227-31.
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    ABSTRACT: The functional characterization of nonsynonymous single nucleotide polymorphisms in human mismatch repair (MMR) genes has been critical to evaluate their pathogenicity for hereditary nonpolyposis colorectal cancer. We previously established an assay for detecting loss-of-function mutations in the MLH1 gene using a dominant mutator effect of human MLH1 expressed in Saccharomyces cerevisiae. The purpose of this study is to extend the functional analyses of nonsynonymous single nucleotide polymorphisms in the MLH1 gene both in quality and in quantity, and integrate the results to evaluate the variants for pathogenic significance. The 101 MLH1 variants, which covered most of the reported MLH1 nonsynonymous single nucleotide polymorphisms and consisted of one 3-bp deletion, 1 nonsense and 99 missense variants, were examined for the dominant mutator effect by three yeast assays and for the ability of the variant to repair a heteroduplex DNA with mismatch bases by in vitro MMR assay. There was diversity in the dominant mutator effects and the in vitro MMR activities among the variants. The majority of functionally inactive variants were located around the putative ATP-binding pocket of the NH(2)-terminal domain or the whole region of the COOH-terminal domain. Integrated functional evaluations contribute to a better prediction of the cancer risk in individuals or families carrying MLH1 variants and provide insights into the function-structure relationships in MLH1.
    Cancer Research 06/2007; 67(10):4595-604. · 8.65 Impact Factor
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    ABSTRACT: A 44-year-old man had a tumor in the lower thoracic esophagus at a health check, and was initially diagnosed as an undifferentiated carcinoma of the esophagus by the esophago-gastric endoscope. Although curative chemoradiotherapy was scheduled after the diagnosis, the interim evaluation revealed that the tumor was malignant melanoma of the esophagus with right renal metastasis. Since then, CVD (cisplatin, vindesine and dacarbazine) therapy, palliative radiotherapy and DAC-Tam (dacarbazine, nimustine, cisplatin and tamoxifen) therapy were carried out, but all of them proved ineffective, and multiple newly metastatic lesions appeared in liver and lymph nodes. Oral intake was impossible because of progressing stricture of the esophagus. As a fourth-line therapy, weekly paclitaxel therapy was started, and his oral intake was improved after the second course. He received the therapy as an outpatient for four months. After the third course, tumor lesions were evaluated as a partial response by CT. Consequently, five courses of the therapy were performed with modest adverse effects. Weekly paclitaxel therapy was reasonably safe as reported in other reports and considered to be a promising regimen for malignant melanoma of the esophagus.
    Gan to kagaku ryoho. Cancer & chemotherapy 08/2006; 33(7):969-72.
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    ABSTRACT: The aim of this study was to evaluate the efficacy and toxicity of 5-fluorouracil (5-FU) and l-leucovorin (I-LV) in 50 patients with advanced or recurrent colorectal cancer in our institute. The dose of 5-FU was 600 mg/m2 and the dose of l-LV was 250 mg/m2. Objective response were 36.8% of patients who had administration of full-dose and 14.8% of patients who had the administration of reduced dose or prolonged interval. No significant difference was observed in clinical benefit rates between patients administrated in full-dose and patients in reduced dose or prolonged interval. Median survival time (MST) of patients in reduced dose or prolonged interval is longer than patients in full-dose. These data suggest that 5-FU/l-LV can be given in the outpatient and yields improved prognosis and minimal adverse reactions even in patients in reduced dose or prolonged interval.
    Gan to kagaku ryoho. Cancer & chemotherapy 08/2005; 32(7):991-5.
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    ABSTRACT: The gene responsible for Peutz-Jeghers syndrome (PJS), LKB1 (also called STK11) was mapped to chromosome 19p13.3 and was found to encode a putative serine/threonine protein kinase, LKB1. As only a limited number (approximately 100) of germline mutations of the gene have been reported, and because the protein function is still unclear, information about LKB1 mutations and their expression should be accumulated to understand the phenotype-genotype correlation of this disease. Here we report a patient with sporadic PJS with early-onset gastric cancer. We found a novel germline frameshift mutation (757-758insT) in the LKB1 gene and a marked reduction in LKB1 protein expression in the carcinoma cells, suggesting that the loss of LKB1 function may have led to the carcinogenesis of the gastric cancer.
    Journal of Gastroenterology 01/2005; 39(12):1210-4. · 3.79 Impact Factor

Publication Stats

69 Citations
411 Views
18.10 Total Impact Points

Institutions

  • 2005–2012
    • Tohoku University
      • Institute of Development, Aging and Cancer
      Sendai-shi, Miyagi-ken, Japan
  • 2007
    • Iwate Prefectural Central Hospital
      Aomori, Aomori Prefecture, Japan