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Biomedical subjects

M Kitajima

Publications and source records attributed to M Kitajima.

At least 37 records · Page 2Linked to original sources

[Clinical evaluation of hepatopancreatoduodenectomy].

The clinical outcome of hepatopancreatoduodenectomy (HPD) carried out in 14 patients in our institute was evaluated retrospectively. In principle, HPD is performed in patients with far-advanced biliary carcinoma extending from the level of the liver to pancreas directly or via metastatic lymph nodes around the head of the pancreas. However, the survival periods after surgery did not improve, contrary to expectations. Curative surgery was not achieved in most patients who underwent HPD, even if resection of the portal vein or hepatoduodenal ligament was performed during surgery. Severe lymphatic, vascular, and neural involvement along the hepatoduodenal ligament existed in those patients. In addition, it is possible that they already had micrometastases to other organs based on a study of the pattern of recurrence after surgery. Quality of life did not appear to improve unless the patients survived more than one year. These findings suggest that HPD may be appropriate for patients in earlier disease stages than those in our series to achieve longer survival. However, HPD is associated with high rates of postoperative complications and operative mortality, especially after pancreatoduodenectomy with liver resection involving more than right hepatectomy. We need to establish the appropriate indications for HPD and improve the safety of the procedure.

Aged↗

[Appropriate extent of lymphadenectomy in esophageal cancer].

Because of the high frequency and widespread distribution of lymph node metastasis in esophageal cancer, three-field dissection was introduced in the early 1980s. Although improvement in the long-term survival rate of patients who undergo three-field dissection has been reported, the clinical significance of cervical lymphadenectomy is still controversial because the effect of improved upper-mediastinal lymphadenectomy in these patients cannot be excluded. Recently, the sentinel node (SN) concept has been validated in gastrointestinal cancers including esophageal cancer using the radio-guided method. Aberrant drainage routes from the primary lesion have frequently been observed in esophageal cancer and are detectable by radio-guided SN mapping. SN navigation is useful to identify SNs as the functional first basin to evaluate the regional lymph node status and to determine the indications for extensive lymphadenectomy in patients with esophageal cancer. Individualized surgical management of patients with esophageal cancer is essential to improve the quality of life of patients and long-term results.

Esophageal Neoplasms↗

[Current status of adjuvant endocrine therapy for hormone responsive breast cancer].

Three important meetings on adjuvant hormone therapy for breast cancer were held recently: the 5th EBCTCG Meeting, NIH Consensus Meeting, 7th International Conference on Adjuvant Therapy of Primary Breast Cancer. The conclusions of these meetings are: 1. adjuvant hormone therapy should be indicated only for patients with estrogen/progesterone receptor positive cancer, 2. five years of tamoxifen is the standard care at present, 3. ovarian ablation by any means has been proved effective in premenopausal patients and LH-RH agonist should be given at least two years, and 4. aromatase inhibitors should not be used in clinical practice, because several prospective randomized trials are ongoing at present. The patients treated with LH-RH agonist combined with tamoxifen showed better relapse-free survival compared with LH-RH agonist alone in the INT-0101 trial. This was an important trial because combined hormone therapy had not been proven more effective than individual hormone therapy previously. Combined hormone therapy including LH-RH agonist may be considered in premenopausal patients. There is a growing consensus that chemotherapy is effective through the ovarian suppression. In this sense, hormonal therapy should be considered first for hormone responsive patients. On the contrary, standard chemotherapy has shifted from CMF combination to an anthracycline containing regimen. Chemoendocrine therapy may be considered in high risk patients.

Antineoplastic Agents, Hormonal↗

Survival of non-small cell lung cancer patients with postoperative recurrence at distant organs.

BACKGROUND: Recurrence after complete resection of non-small cell lung cancer (NSCLC) is often observed. However, its influence on the prognosis of patients with recurrence is still unclear. PATIENTS AND METHODS: Of 468 consecutive patients with NSCLC undergoing complete resection during 10 years, 118 experienced recurrence at distant organs. In such patients, the influence of the following variables on post-recurrent survival was analyzed; sex, age at recurrence, disease-free interval, cell type, pathological (p-) stage at operation, adjuvant therapy (thoracic radiation and/or chemotherapy), site of recurrence, and treatment against recurrence. To identify independent factors, multivariate analysis was performed for variables which were considered to be influential in univariate analysis. RESULTS: Mean post-recurrent survival time was 418 days, and survival rate at 2-years was 15.7%. Multivariate analysis revealed that female, early p-stage, younger age at recurrence, metastasectomy and intra-pulmonary metastasis were the significant favorable factors in patients with distant metastases. Adjuvant therapy and bone metastasis were marginally significant unfavorable factors. Chemotherapy for recurrence tended to prolong survival. Length of disease-free survival and post-recurrent survival exhibited a positive relationship with p-stage. Seven out of 16 patients who underwent metastasectomy survived more than 1000 days after recurrence. CONCLUSIONS: Patients even with recurrence in distant organs could expect for long survival if they are in the early p-stage of primary cancer or a resectable recurrent disease.

Adenocarcinoma↗

Laparoscopic detection of sentinel lymph nodes in gastrointestinal cancer: a novel and minimally invasive approach.

Although the sentinel node (SN) concept has been validated in malignant melanoma and breast cancer, the application of this concept for other solid tumors, including gastrointestinal (GI) cancer, is still controversial. We have demonstrated the feasibility of radioguided SN mapping during laparotomy in patients with esophageal, gastric, and colorectal cancers. In 188 patients, the SNs identified by this technique had an overall diagnostic accuracy of 96% for regional lymph node metastasis. Aberrant drainage sites that have been called skip metastasis from the primary lesion were detectable using this method. More recently, we have undertaken SN mapping during laparoscopic surgery. A combination of radiotracer and blue dye optimized the identification of SNs that drained GI cancers. Our preliminary data indicate that laparoscopic mapping of the SN is a sensitive intraoperative technique for identifying lymph node micrometastasis, and we believe that it will become an important component of a minimally invasive approach to early-stage GI cancers.

Colonic Neoplasms↗

[Clinical significance of sentinel node navigation surgery in the treatment of early gastric cancer].

Radical lymphadenectomy is the standard surgical approach even for early-stage gastric cancer with a relatively low incidence of lymph node metastasis because of the limited sensitivity of diagnostic imaging to detect micrometastasis in regional lymph nodes. The sentinel node (SN) concept is one topic among novel diagnostic procedures for micrometastasis. The SN is defined as the first draining node from the primary lesion and it would be the first site of micrometastasis. SN biopsy has been clinically validated and applied for the surgical treatment of malignant melanoma and breast cancer. Although the feasibility of this technique in other solid tumors including gastric cancer is still controversial, there are several reports demonstrating the diagnostic significance of SN mapping in early gastric cancer. We have established radio-guided SN mapping for early gastric cancer, and the diagnostic accuracy using this procedure in cT1N0 cases reached 98%. The radio-guided method allows us to detect the SN in endoscopic surgery quantitatively and reproducibly. Validation of the SN concept in gastric cancer in a multi-centric clinical trial is essential for clinical application of this procedure, including the establishment of a novel, minimally invasive approach for early-stage gastric cancer.

Humans↗

[Clinical experience of intra-arterial chemotherapy for liver metastases of breast cancer patients].

The aim of this study was to evaluate retrospectively the effect of intra-arterial chemotherapy for liver metastases of breast cancer patients. Eleven patients treated between August 1991 and July 1997 at Keio University Hospital, Tokyo, Japan, were the subjects for this study. The duration of disease-free periods after the operation ranged from 9 to 78 months (median 27 months). The site of the recurrence was the liver alone in 6 cases, and the liver and lung in 1 case, bone in 1 case, lymph nodes in 2 cases, and a local region, in 1 case. The main drugs were adriamycin (ADM) and 5-fluorouracil (5-FU), administered in a single injection or continuously via an indwelling catheter in the hepatic artery. This method had a 36% response rate, including PR in 4 cases, NC in 3 cases and PD in 4 cases. The survival duration was 1 to 19 months (median 14 months) following this treatment, and 3 to 49 months (median 17 months) after the recognition of the recurrence. The only side effects of Grade 3 or 4 were leucocytopenia or granulocytopenia and nausea. These results suggest that intra-arterial chemotherapy for liver metastases of breast cancer patients may be an effective method for the control of liver metastases with minor side effects. However, further study may be necessary to establish methods to manage the indwelling catheter and to control patients with multiple metastases of the other organs, to improve the prognosis for recurrent breast cancer patients.

Adult↗

[En bloc resection of the hepatoduodenal ligament for advanced carcinoma of the biliary tract].

Theoretically, en bloc resection of the hepatoduodenal ligament is considered to be the most radical procedure for advanced carcinoma of the biliary tract. However, this procedure involves perioperative difficulties such as hepatic ischemia, portal congestion, patency of reconstructed vessels, and high incidence of operative mortality, moreover, when it is combined with resection of the liver and/or pancreas. We developed several tactics in vascular reconstruction, hepatic resection, and pancreatoduodenectomy in order to decrease the operative morbidity and mortality. We preferred to anastomose the portal vein and hepatic artery separately to avoid total hepatic ischemia, and used the porto-systemic bypass during prolonged portal reconstruction. We resected the liver without vascular clamping to minimize hepatic ischemia, and employed the simplified method of pancreatojejunostomy. To date, we performed 4 hepatoligamentectomies and 4 hepatoligament-pancreatoduodenectomies with no operative mortality, although long-term survivors were not encountered. This procedure should be evaluated with more clinical experiences after its safety and indication was established.

Aged↗

Dynamical Auger emission induced by multistate vibronic coupling in the core-excited states of the BCl3 molecule.

The Auger emission following the resonant excitation of the BCl3 molecule has been investigated using monochromatized synchrotron radiation. The B 1s excitation to the unoccupied Anti-bonding 4e(') orbital enhances the shoulder structure in the low kinetic energy side of the photoemission from the 2e(') valence bonding orbital. Based on a series of quantum mechanical calculations, this shoulder structure is interpreted as the dynamical Auger emission which reflects the B-Cl stretching nuclear motion and appears as a result of the purely multistate vibronic coupling effect among the Jahn-Teller split B 1s(-1)4e(') E' states and the closely lying B 1s(-1)3a(')(1) A'1 state.

Journal Article↗

Identification of three human type-II classic cadherins and frequent heterophilic interactions between different subclasses of type-II classic cadherins.

We identified three novel human type-II classic cadherins, cadherin-7, -9 and -10, by cDNA cloning and sequencing, and confirmed that they interact with catenins and function in cell-cell adhesion as do other classic cadherins. Cell-cell binding activities of the eight human type-II classic cadherins, including the three new molecules, were evaluated by long-term cell-aggregation experiments using mouse L fibroblast clones transfected with the individual cadherins. The experiments indicated that all the type-II cadherins appeared to possess similar binding strength, which was virtually equivalent to that of E-cadherin. We next examined the binding specificities of the type-II cadherins using the mixed cell-aggregation assay. Although all of the type-II cadherins exhibited binding specificities distinct from that of E-cadherin, heterophilic interactions ranging from incomplete to complete were frequently observed among them. The combinations of cadherin-6 and -9, cadherin-7 and -14, cadherin-8 and -11, and cadherin-9 and -10 interacted in a complete manner, and in particular cadherin-7 and -14, and cadherin-8 and -11 showed an indistinguishable binding specificity against other cadherin subclasses, at least in this assay system. Although these data were obtained from an in vitro study, they should be useful for understanding cadherin-mediated mechanisms of development, morphogenesis and cell-cell interactions in vivo.

Amino Acid Sequence↗

Increased formation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine, in human breast cancer tissue and its relationship to GSTP1 and COMT genotypes.

Reactive oxygen species (ROS) induced damage to DNA plays a major role in carcinogenesis. In order to estimate the level of oxidative damage and its role in breast cancer, 8-hydroxy-2'-deoxyguanosine (8-OHdG) was determined in DNA isolated from human breast tissue. Furthermore, we investigated whether polymorphisms in genes for enzymes involved in generation and elimination of ROS had any association with the level of 8-OHdG in breast tissue. In this study, the level of 8-OHdG in DNA was measured by the high performance liquid chromatography-electrochemical detector (HPLC-ECD) method. Genotypes of cytochrome P450 (CYP)1A1, glutathione S-transferase (GST)M 1, GSTP1 and catechol O-methyltransferase (COMT) were determined by PCR-based restriction fragment length polymorphism analysis. A total of 61 Japanese patients were included in the study. The mean level of 8-OHdG in DNA of breast cancer tissues was 2.07 +/- 0.95 per 10(5) dG residues, while the mean level of 8-OHdG in DNA of non-cancerous breast tissues was 1.34 +/- 0.46 per 10(5) dG residues. The 8-OHdG levels in DNA of breast cancer tissues were significantly higher than those of their corresponding non-cancerous breast tissues (P < 0.0001). There was negative correlation between the clinical stage and the mean level of 8-OHdG in DNA of breast cancer tissues. Furthermore, patients with genotype of high GSTP1 activity had lower level of 8-OHdG in DNA of breast cancer tissues than others. On the contrary, the mean level of 8-OHdG in DNA of breast cancer tissues was higher among patients with genotype of high COMT activity. Our findings support the assumption that cancer cells are more exposed to oxidative stress than adjacent non-cancerous tissue. Genetic polymorphisms in enzymes involved in ROS metabolism may have a role in individual susceptibility to oxidant-related breast disease. At the same time, reduction of oxidative stress is thought to be a very important measure for primary prevention of breast cancer.

8-Hydroxy-2'-Deoxyguanosine↗

Telomerase activity as an indicator of malignant potential in iodine-nonreactive lesions of the esophagus.

BACKGROUND: Iodine-nonreactive lesions of esophageal epithelium often are associated with dysplasia and carcinoma. The authors examined the usefulness of telomerase activity as an indicator for esophageal carcinogenesis in such lesions. METHODS: Telomerase activity was measured using the telomeric repeat amplification protocol assay in 18 samples of iodine-nonreactive lesions apart from the primary tumor in surgically resected specimens obtained from patients with esophageal squamous cell carcinoma (ESCC) and 55 endoscopic punch biopsies of iodine-nonreactive lesions obtained from 25 patients with ESCC and 30 patients who had undergone endoscopic examination for other reasons. RESULTS: Ten of 18 iodine-nonreactive samples (56%) obtained from surgically resected specimens showed telomerase activity. In all ten telomerase positive samples, carcinoma in situ (CIS) was observed in iodine-nonreactive mucosa by light microscopy. In eight telomerase negative samples, no tumor tissue was observed in iodine-nonreactive lesions. In a parallel study, telomerase activity was detected in 28 of 55 endoscopic punch biopsy specimens (51%). CIS was observed in 25 of 28 iodine-nonreactive lesions with positive telomerase activity (89%), and tumor tissue was not observed in the other 3 samples (11%), which included 2 cases of severe dysplasia and 1 case of moderate dysplasia. No tumor tissue was observed in any of the 27 telomerase negative samples. CONCLUSIONS: Positive and negative telomerase activity was found to be correlated with the presence and absence, respectively, of immortalized tumor cells in iodine-nonreactive lesions. The measurement of telomerase activity in iodine-nonreactive lesions independently contributes to the selection of an appropriate therapeutic strategy.

Adult↗

A new predictive factor for hepatocellular carcinoma based on two-dimensional electrophoresis of genomic DNA.

Molecular genetic analyses have clarified that accumulation of genomic changes provides important steps in carcinogenesis and have identified a number of valuable genetic markers for certain cancers. To date, however, no prognostic markers have been identified for hepatocellular carcinoma (HCC). In this study, we used restriction landmark genomic scanning (RLGS), a new high-speed screening method for multiple genomic changes, to detect unknown genetic alterations in HCC. Thirty-one HCC samples and their normal counterparts were examined by RLGS. Eight spot changes were common in several cases, and all were seen only on the HCC profile. Five of these spots were detected in more than 12 of 31 cases (38.7%). Viral infection had no influence on changes in the RLGS spots. The disease-free survival rate for patients with > or =16 changed RLGS spots was significantly lower than that for patients with fewer changed RLGS spots (< or =15 spots) (P<0.001). In multivariate analysis, the number of changed spots was proven to retain an independent prognostic value (relative risk 1.095: P = 0.0031). These results suggest that the number of changed RLGS spots may be a useful biological marker for recurrence of HCC.

Adult↗

Progression of human breast cancers to the metastatic state is linked to genotypes of catechol-O-methyltransferase.

There is increasing evidence that catecholestrogens may contribute to the development of breast cancer. Specifically, inactivation of catecholestrogens may prevent the genesis and arrest the progression of the disease. Catechol-O-methyltransferase (COMT), Glutathione S-transferase (GST) M1 and GSTP1 are responsible for the detoxification of catecholestrogens, and are polymorphic in the human population. In this study, a PCR-based restriction fragment length polymorphism analysis was performed to determine genotypes of the COMT, GSTM1 and GSTP1 genes. We investigated the relationship between the germline polymorphism of these genes and clinico-pathological characteristics in 140 patients with breast cancer. Among 73 patients with the low activity COMT allele, 49 (67%) had regional lymph node metastasis. On the other hand, only 27 (40%) of 67 patients without the low activity allele had lymph node metastasis. The COMT genotype was significantly associated with clinical stage and the extent of regional lymph node metastasis of breast cancer (P<0.05). However, polymorphisms of the GSTM1 and GSTP1 gene were not associated with clinico-pathological factors. Our findings suggest that the allele encoding for low activity COMT may contribute to the progression of breast cancer.

Adult↗

Three cases of spinal dural AVF: evaluation with first-pass, gadolinium-enhanced, three-dimensional MR angiography.

A first-pass, contrast-enhanced three-dimensional (3D) magnetic resonance (MR) angiography with short acquisition time was performed for three consecutive cases with suspected spinal arteriovenous fistula (AVF). This MR technique demonstrated the feeding arteries and draining veins of the spinal dural AVF, and was very useful for the definite diagnosis of the lesions as a disease with arteriovenous shunt. With this MR technique, we could localize the feeding artery and shunt before conventional angiography. J. Magn. Reson. Imaging 2000;12:949-952.

Aged↗

Targeting activated lymphocytes with an entirely human immunotoxin analogue: human pancreatic RNase1-human IL-2 fusion.

A hybrid human protein was produced in E. coli by fusing the genes encoding human pancreatic RNase1 (hpRNase1) and human IL-2 (hIL-2). The recombinant hpRNase1-hIL-2 inhibited protein synthesis in HTLV-1-infected, malignant T cells, which hyperproduce high affinity IL-2 receptors, with an IC(50)of 2x10(-8) M, whereas no inhibition was detectable in control cells with lower affinity receptors. HpRNase1 alone had an IC(50)of almost 10(-3) M. A molar excess of hIL-2 blocked the protein synthesis inhibition dose-dependently. In a human mixed lymphocyte culture, hpRNase1-hIL-2 inhibited the proliferation of responder cells with potency comparable to that of cyclosporine, while non-effective doses of FK506 importantly improved its potency. Despite its short half-life in animals, hpRNase1-hIL-2 rapidly enters cells in a few minutes and arrests the protein translation in less than 10 h. Thus, hpRNase1-hIL-2 may be useful to selectively eliminate activated lymphocytes hyperproducing high affinity IL-2 receptors, as in allograft rejection, graft-versus-host disease, autoimmune disorders, adult T cell leukaemia and other lymphoproliferative or retroviral malignancies including HIV infection, without inducing general immunosuppression. As an entirely human "immunotoxin analogue" it may alleviate the dose limiting toxicity and immunogenicity of conventional immunotoxins.

Animals↗