PubMed Health⌕ Search

Biomedical subjects

H Mochizuki

Publications and source records attributed to H Mochizuki.

At least 19 recordsLinked to original sources

Significant correlation between expression of interleukin-1alpha and liver metastasis in gastric carcinoma.

BACKGROUND: Interleukin (IL)-1 has been reported to augment the hematogeneous metastasis of some cancers by inducing the expression of adhesion molecules on vascular endothelial cells and also increasing the expression of proteases from tumor cells in vitro. The purpose of this study was to determine the clinical significance of the IL-1alpha expression in primary tumors of gastric carcinoma. METHODS: Paraffin embedded sections of the tumors obtained from 109 patients who underwent a gastrectomy for gastric carcinoma with subserosal invasion were stained for IL-1alpha by using the streptavidin biotin method. Staining was considered positive when 10% or more of the malignant cells displayed cytoplasmic staining. RESULTS: Sixty (55.0%) tumors expressed IL-1alpha. Positive staining for IL-1alpha was more likely in patients with differentiated tumors than in those with undifferentiated tumors. The expression of IL-1alpha showed a significant correlation with liver metastasis. Of the 84 patients receiving a curative resection, those with tumors expressing IL-1alpha had a significantly higher incidence of liver recurrence than those without. A logistic regression analysis revealed positive staining for IL-1alpha to be the best predictive factor of patients who develop liver recurrence. CONCLUSIONS: The authors' results suggest that the immunohistochemical expression of IL-1alpha is a useful predictor of liver recurrence in patients undergoing a curative resection for gastric carcinoma with subserosal invasion.

Biomarkers, Tumor↗

Interhemispheric facilitation of the hand motor area in humans.

1. We investigated interhemispheric interactions between the human hand motor areas using transcranial cortical magnetic and electrical stimulation. 2. A magnetic test stimulus was applied over the motor cortex contralateral to the recorded muscle (test motor cortex), and an electrical or magnetic conditioning stimulus was applied over the ipsilateral hemisphere (conditioning motor cortex). We investigated the effects of the conditioning stimulus on responses to the test stimulus. 3. Two effects were elicited at different interstimulus intervals (ISIs): early facilitation (ISI = 4-5 ms) and late inhibition (ISI > or = 11 ms). 4. The early facilitation was evoked by a magnetic or anodal electrical conditioning stimulus over the motor point in the conditioning hemisphere, which suggests that the conditioning stimulus for early facilitation directly activates corticospinal neurones. 5. The ISIs for early facilitation taken together with the time required for activation of corticospinal neurones by I3-waves in the test hemisphere are compatible with the interhemispheric conduction time through the corpus callosum. Early facilitation was observed in responses to I3-waves, but not in responses to D-waves nor to I1-waves. Based on these results, we conclude that early facilitation is mediated through the corpus callosum. 6. If the magnetic conditioning stimulus induced posteriorly directed currents, or if an anodal electrical conditioning stimulus was applied over a point 2 cm anterior to the motor point, then we observed late inhibition with no early facilitation. 7. Late inhibition was evoked in responses to both I1- and I3-waves, but was not evoked in responses to D-waves. The stronger the conditioning stimulus was, the greater was the amount of inhibition. These results are compatible with surround inhibition at the motor cortex.

Conditioning, Psychological↗

Cancer cells surviving hypoxia obtain hypoxia resistance and maintain anti-apoptotic potential under reoxygenation.

In solid tumors hypoxia and reoxygenation may be important factors in secondary expansion after anti-cancer therapy. Our study examined the effect of hypoxia and reoxygenation on the apoptotic potential of cancer cells. Four experimental groups were studied using a human colorectal cancer cell line (HCT116) that is apoptosis-competent in conventional culture: (1) sham, cells grown under conventional conditions; (2) hypoxic, cells cultured in 95% N2 and 5% CO2 for 24 hr; (3) continued hypoxic, cells cultured for 48 hr; and (4) reoxygenation, cells grown in hypoxic conditions for 24 hr followed by another 24 hr under conventional conditions. Protein expression of p53, bcl-2 and PCNA were determined by immunohistochemistry and immunoblotting (p53), and viable cell growth rate was determined. Hypoxia for 24 hr induced significant up-regulation of p53 and bcl-2 expression, accompanied by significant decreases of cell growth rate and PCNA expression. Up-regulation of p53 and bcl-2 expression persisted with both continued hypoxia and reoxygenation, despite increased cell growth rate and PCNA expression. Cells escaping hypoxia acquired sustained resistance to apoptosis and proliferate despite an elevated p53 level, suggesting that p53 transfer to hypoxic solid tumor should be reevaluated as a cancer gene therapy approach.

Apoptosis↗

Expression of cyclooxygenase-2 in human gastric adenomas and adenocarcinomas.

BACKGROUND AND OBJECTIVES: The increased expression of cyclooxygenase (COX)-2 has been implicated in the development and progression of colorectal cancer. We sought to determine the involvement of COX-2 in human gastric cancer. MATERIALS AND METHODS: COX-2 mRNA was assayed in both gastric cancer cell lines and biopsy specimens from 37 gastric adenocarcinomas, five gastric adenomas, and five hyperplastic polyps by reverse transcription-polymerase chain reaction. RESULTS: COX-2 mRNA was found in four of five gastric cancer cell lines, two from intestinal type and two from diffuse type. COX-2 mRNA was expressed in 19 of 37 (51%) human gastric cancer specimens. The tumor diameter was greater in patients with COX-2 expression than in those without (6.5 +/- 4.6 vs. 3.8 +/- 2.7 cm, P < 0.05). The incidence of COX-2 mRNA expression was significantly higher in patients with pT2-pT4 tumors than in those with pT1 tumors (71 vs. 35%, P < 0.05). Significantly higher expression of COX-2 mRNA was also observed in patients with lymph node involvement than in those without (75 vs. 40%, P < 0.05). COX-2 mRNA was found in one of five adenomas, while it was absent in five hyperplastic polyps. The paired normal gastric musosa did not express COX-2 mRNA in any of the 47 patients. CONCLUSIONS: These results provide clinical evidence that COX-2 may contribute to tumor progression in human gastric adenocarcinoma.

Adenocarcinoma↗

5'-deoxy-5-fluorouridine, medroxyprogestrone acetate and mitoxantrone hydrochloride for advanced or recurrent breast cancer.

BACKGROUND: In treating advanced or recurrent breast cancer, anthracycline-containing chemotherapy is used for palliation and to maintain quality of life. However, there are several drawbacks including therapeutic failure and cardiotoxicity. We evaluated the efficacy and toxicity of combination chemotherapy with 5'-deoxy-5-fluorouridine (5'-DFUR), medroxyprogestrone acetate (MPA) and mitoxantrone hydrochloride (MIT). METHODS: Sixteen patients with advanced or recurrent breast cancer were enrolled. Chemotherapy was given in a 28-day cycle, starting with MIT 10 mg/m2 intravenously on day 1, then oral 5'-DFUR 800 mg and MPA 800 mg daily. Two or more cycles were given. RESULTS: Fifteen patients were assessable for response and toxicity. Thirteen patients had been treated previously with an anthracycline containing regimen and 2 with CMF. There were 2 partial response patients (13.3%) and 1 complete response patient (6.7%). There were 11 patients showing no change (NC) (73.3%), one of whom was a minor responder and 7 with a long period of NC. There was only one with progressive disease patient. The overall response rate was 20.0%. Adverse events occurred in 5 patients (33.3%). Myelosuppression was the most common with 5 patients becoming leukopenic (33.3%). Nausea/vomiting was the second most common side effect, affecting 2 patients (13.3%). CONCLUSION: Given its high efficacy and preservation of QOL, the combination of MIT, 5'-DFUR and MPA can be a 2nd or 3rd line therapy for advanced or recurrent breast cancer, especially for anthracycline-resistant cases.

Adult↗

Dietary taurine potentiates polychlorinated biphenyl-induced hypercholesterolemia in rats*

The effect of dietary taurine on cholesterol metabolism and the distribution of lipoprotein-cholesterol in serum of rats fed a diet containing polychlorinated biphenyls (PCB) was examined. Young male Wistar rats (60 g) were fed diets containing 0.2 g/kg diet of PCB and/or 30 g/kg diet of taurine for 15 days. The experiment was performed as the 2 (PCB) x 2 (taurine) factorial design. The addition of PCB elevated serum levels of total- and HDL-cholesterol and apolipoprotein A-I, which is a major apolipoprotein of HDL. Simultaneous supplementation of taurine with PCB amplified the increase of the serum level of total- and HDL-cholesterol. Hepatic concentrations of cholesterol and total lipids were significantly elevated by the supplementation of PCB, and taurine significantly amplified these increases caused by PCB. PCB suppressed hepatic cholesterol 7alpha-hydroxylase (CYP7A1) gene expression, and taurine induced CYP7A1 gene expression. Taurine also enhanced PCB-induced elevation of malic enzyme mRNA in the liver. These results suggest that taurine enhanced PCB-induced hyper-alpha-cholesterolemia and that taurine has a role in increasing HDL-cholesterol.

Journal Article↗

Iron accumulation in the substantia nigra of autosomal recessive juvenile parkinsonism (ARJP).

Autosomal recessive juvenile parkinsonism (ARJP) is a distinct clinical and genetic entity characterized by highly selective neuronal death in the substantia nigra (SN) and locus coeruleus neurons without Lewy body formation. The mechanism of neuronal death of ARJP is still unknown. Our study demonstrated that iron staining was more intense in ARJP than in both controls and sporadic Parkinson's disease (PD), and there were differences in the pattern of distribution of iron staining between ARJP and PD. In addition neurites of SN in ARJP showed intense iron staining. Thus, we postulate that oxidative stress may play an important role in the neurodegeneration that occurs in ARJP.

Journal Article↗

A single motor unit recording technique for studying the differential activation of corticospinal volleys by transcranial magnetic stimulation.

The purpose of this method is to establish a single motor unit recording technique to study the differential activation of corticospinal volleys by various types of transcranial magnetic stimulation (TMS). TMS is performed with various coil orientations over the hand or leg motor areas and surface EMG, and single motor unit recordings are made either from the studied hand or leg muscle. Transcranial electrical stimulation (TES) is also performed over the motor cortex as well as at the foramen magnum level to determine the latency of D waves. The intensity of stimulation is set just above the motor threshold for each type of stimulation. This method makes it possible to activate some I volleys (especially I1 and I3 waves) preferentially, if not selectively, from the hand and leg motor areas. The obtained results accord well with recent epidural recording studies, which lends support to the validity of this method.

Differential Threshold↗

Somatosensory evoked potential recovery in myotonic dystrophy.

OBJECTIVE: To evaluate recovery functions of the sensory cortex using somatosensory evoked potentials (SEPs) elicited by paired stimuli of the median nerve in patients with myotonic dystrophy (MD). SUBJECTS/METHODS: Twelve MD patients were enrolled in the present investigation. Five patients with facioscapulohumeral muscular dystrophy (FSH) and 12 healthy volunteers were studied as control groups. SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single pulse or paired-pulse stimuli at various interstimulus intervals (ISIs) (10, 20, 40, 60, 80, 100, 150, 200 and 300 ms) were given. Recovery functions of N9, N20onset-N20peak, N20-P25 and P25-N33 components were studied. RESULTS: Conventional SEPs to a single stimulus were normal in the latency and amplitude in all the patients. Recovery functions of both N9 and N20o-N20p components were normal in the patients. In contrast, in MD patients, disinhibited or hyperexcitable recovery pattern was observed in recovery curves of the N20-P25 or P25-N33 components, whereas those were normal in FSH patients. CONCLUSIONS: Disinhibited cortical excitability (or hyperexcitability) is present in the sensory cortex in patients with myotonic dystrophy. This may reflect cortical pathology or functional alteration of the sensory cortex in MD.

Adult↗

Development of bronchial hyperresponsiveness during childhood.

Bronchial hyperresponsiveness (BHR) produces the characteristic pathological abnormalities seen in asthma and clearly plays a central role in the pathophysiology of asthma. The presence of BHR has been demonstrated in infants with asthma, as has the possibility of BHR persisting through the childhood period. The level of BHR may not only reflect the state of the airways, as a marker of airway dysfunction, but may also predict the persistent prognosis of the disease. Thus, measurement of BHR may provide important information about the symptoms and lung function in children with asthma. In view of multiple pathophysiological mechanisms, BHR does not seem to have a single cause. Many potential confounding variables, such as age, gender and genetic status, and some environmental factors, such as allergens, infections, and pollutants, could be responsible for the establishment of childhood BHR. There may be differences between the mechanisms that induce transient BHR and the mechanisms that induce persistent BHR. Also, there may be differences between the causes that induce BHR in the infantile period and the causes that maintain persistent BHR during childhood asthma. There is also disagreement as to the most suitable method to measure BHR in children, especially in infants. The assessment of BHR in young children has not been uniformly successful, and measurements of BHR changes over the childhood period (are associated with a number of problems. To resolve these problems, there may be two ways to study childhood BHR. One is to use age-matched specific techniques to clarify the precise BHR in each age group; the other is to use simple techniques that can be performed over the childhood period on a large number of subjects. In studies of infantile respirator, dysfunction the ultimate goal is to establish a simple, noninvasive method by which measurements of respiratory function may be obtained in infants. Further investigations and acceptable methods will be needed to clarify, the mechanisms involved in the establishment of asthma throughout the childhood period.

Asthma↗

Mechanism of the inhibitory effect of protease inhibitor on tumor necrosis factor alpha production of monocytes.

If the inflammatory response becomes excessive or uncontrolled by some stimuli, inappropriate inflammatory responses occur. Monocytes are extremely important cells for regulating the cytokine network and tumor necrosis factor alpha (TNFalpha) and interleukin- (IL) 10, which are mainly synthesized by monocytes, are representative cytokines that play a central role in the cytokine network. Protease inhibitors such as gabexate mesilate (GM) and ulinastatin (UTI) have been shown to have various beneficial effects by inhibiting the activation of leukocytes, but the mechanism for this has yet to be fully elucidated. In this study we investigated the mechanism of the inhibitory effect of protease inhibitors on the proinflammatory cytokine production of lipopolysaccharide- (LPS) stimulated monocytes. LPS-stimulated monocytes were treated with GM or UTI. The value of TNFalpha and IL-10 in the culture medium of monocytes was measured and each mRNA expression was assayed. The inhibitory effect of protease inhibitors on the activity of intracellular signal transduction pathways such as protein kinase C (PKC) and nuclear factor kappa B (NFkappaB) were also evaluated. GM decreased the TNFalpha production of LPS-stimulated monocytes as shown by the inhibition of mRNA expression and increased the IL-10 production of LPS-stimulated monocytes. GM also suppressed the NFkappaB activity of LPS-stimulated monocytes. UTI decreased the TNFalpha production of LPS-stimulated monocytes, but did not inhibit the TNFalpha mRNA expression. The present study shows that the inhibitory effect of GM on the TNFalpha production of activated human monocytes is mediated by the suppression of NFkappaB activation, while the mechanism of UTI inhibiting TNFalpha production of human monocytes may be due to the inhibition of either the translation or secretion of TNFalpha.

Cells, Cultured↗

Increased monocyte activation in elderly patients after surgical stress.

OBJECTIVE: To investigate age-related changes in the host response to surgical stress. The clinical course, serum interleukin-6 (IL-6) levels, monocyte production of tumor necrosis factor-alpha (TNF-alpha), and monocyte expression of CD11b/CD18 were used as markers of the systemic response. METHODS: Patients with gastric cancer, undergoing distal gastrectomy were divided into 2 groups: >75 years of age (elderly group) and < or =75 years of age (young group). Serum IL-6 levels, TNF-alpha production and CD11b/CD18 expression by monocytes, and the postoperative clinical course were compared between the 2 groups. RESULTS: TNF-alpha production by lipopolysaccharide-stimulated monocytes and CD11b/CD18 expression on monocytes after surgical stress were significantly higher in the elderly than in the young group. Moreover, serum IL-6 levels on the first postoperative day in the elderly group were significantly higher than those in the young group. The incidence and duration of systemic inflammatory response syndrome (SIRS) were significantly greater in the elderly than in the young group. CONCLUSIONS: The activation of monocytes and hypercytokinemia occur readily after surgical stress in the elderly and may therefore contribute to SIRS and increased susceptibility to postoperative complications.

Aged↗

Analysis of the P3 promoter of the human parathyroid hormone (PTH)/PTH-related peptide receptor gene in pseudohypoparathyroidism type 1b.

Hypocalcemia and hyperphosphatemia caused by PTH resistance are the only discernible abnormalities in pseudohypoparathyroidism type 1b (PHP-1b). Because of the selective resistance toward PTH, inactivating mutations in its receptor, the PTH/PTH-related peptide receptor (PTHR1), were thought to be responsible for PHP-1b. However, gene abnormalities responsible for PHP-1b have not been identified in the coding region and well conserved promoters (P1 and P2) of the PTHR1 gene. The purpose of the present study was to analyze the structure of the P3 promoter, the main promoter of the human PTHR1 gene in kidney, in patients with PHP-1b. Southern analysis of genomic DNA from lymphoblastoid cell lines of eight nonfamilial patients with PHP-1b revealed neither gross rearrangements nor methylation abnormalities in the P3 promoter region of the PTHR1 gene. Sequencing revealed no abnormalities in the P3 promoter region, although one patient was homozygous for an (AAAG)n polymorphic variant. In conclusion, despite the selective resistance toward PTH in the kidney, which mainly uses the PTHR1 P3 promoter, PHP-1b in eight cases is not associated with structural abnormalities in this promoter. This study also indicates that inactivation of the P3 promoter is not achieved by methylation as tested in patients' genomic DNA from lymphoblastoid cell lines. The influence of alterations in the polymorphic A-rich repeat sequence on promoter activity warrants further study.

Adolescent↗

Relationship between bronchial hyperresponsiveness and development of asthma in wheezy infants.

STUDY OBJECTIVES: To evaluate the relationship between bronchial hyperresponsiveness (BHR) in infants with wheezing and the subsequent development of asthma. INTERVENTION: Bronchial reactivity to inhaled methacholine (BRm) during the infantile period was studied using the transcutaneous partial pressure of oxygen (tcPO(2)) method. Children were followed long-term for the development of asthma. PATIENTS: Fourteen children with bronchiolitis (mean age, 0.7 years) and 48 with wheezy bronchitis (mean age, 2.3 years) were enrolled. For comparison, 40 children with asthma (mean age, 4.6 years) and 27 healthy control subjects without chronic respiratory disease (mean age, 2.7 years) were studied. MEASUREMENTS: Consecutive doses of methacholine were doubled until a 10% decrease in tcPO(2) from baseline was reached. The cumulative dose of methacholine (Dmin) at the inflection point of tcPO(2) (Dmin-PO(2)) was recorded. RESULTS: During > 10 years of follow-up, seven patients with bronchiolitis developed asthma and all patients in the higher BRm set developed asthma, compared with none in the lower BRm set. In the wheezy bronchitis group, Dmin-PO(2) values in the 32 patients who developed asthma were lower than those in patients who had not developed asthma (p < 0.001). CONCLUSIONS: We concluded that there is a tendency for infants with a clinical diagnosis of bronchiolitis or wheezy bronchitis and who show BHR in the infantile period to develop asthma. The presence of increased BHR after infantile respiratory diseases associated with wheezing may be a prelude to the development of childhood asthma.

Asthma↗

Protection of mice from LPS-induced shock by CD14 antisense oligonucleotide.

CD14 is a pattern recognition receptor on myeloid cells and plays a pivotal role in an innate immune system that is responsible for Gram-negative and Gram-positive bacteria infection. Lipopolysaccharide (LPS), a cell wall component of Gram-negative bacteria, can induce production of a large quantity of proinflammatory cytokines into the circulation mediated by CD14-mediated macrophages and monocytes. These cytokines eventually cause septic shock. Several in vitro and in vivo studies have shown that suppression of a CD14 function by a CD14 antibody led to an inhibition of the production of proinflammatory cytokines such as TNF-alpha, IL-1 beta, and IL-8. In the present study, we found that CD14 antisense oligonucleotide (ODN) can prevent lethal LPS shock in D-galactosamine-sensitized mice. This ODN inhibited CD14 expression in a mouse macrophage cell line, RAW264.7, and suppressed production of TNF-alpha in LPS-stimulated RAW264.7 cells. Furthermore, we designed a consensus antisense ODN that could hybridize human and mouse CD14 RNA, and we evaluated its efficacy. The consensus antisense ODN rescued mice primed with Mycobacterium bovis bacillus Calmette-Guerin (BCG) from the LPS-induced lethal shock. In this model, the CD14 antisense ODN down-regulated LPS-elicited CD14 expression in the liver, resulting in a decrease in LPS-induced TNF-alpha production. These findings suggest that the CD14 antisense ODN is distributed in the liver and efficiently suppresses LPS-induced TNF-alpha production by reducing CD14 expression on Kupffer cells. This CD14 antisense ODN may be useful for the development of a therapeutic agent against sepsis and septic shock.

Animals↗

[An 84-year-old woman with progressive mental deterioration and abnormal behavior].

We report an 84-year-old woman with progressive mental deterioration. She was well until January 1994, when she was 80 years of the age. At that time she developed a delusional ideation, in that she stated that she would be killed by her fellow members of the society for elderly, in which she was belonging. At times, she closed the shutter of her house saying that a stranger was wandering outside of her house. In 1995, she could not identify the face of her son's wife. When she went out for shopping, she lost her way to the home. She prowled about in and out of her home. In 1996, she had to be admitted to a nursing home, where quarrelled with other patients and behaved violently. She was admitted to the neurology service of Hatsuishi Hospital on November 20th, 1997. Family history revealed that her mother was said to be demented. On admission, she was alert and behaved in a good manner. She was disoriented to the time and unable to do serial 7. Her memory was very poor. She did not show aphasia or apraxia. Cranial nerves appeared to be intact. She showed no weakness or muscle atrophy. Gait was normal for her age. Plastic rigidity was noted in four limbs more on the right side. No ataxia was noted. Deep tendon reflexes were exaggerated, however, no Babinski sign was noted. Sensory examination was intact. Her hospital course was characterized by the development of progressive gait disturbance, violent behaviour, and prowling around. On November 30th, 1998, she fell down and suffered from a fracture in the neck of her femur. Although replacement of the femur head was performed, she became unable to walk after this episode. Her mental functions deteriorated further. She developed pneumonia and expired on February 2, 1999. She was discussed in a neurological CPC and the chief discussant arrived at a conclusion that the patient probably had diffuse Lewy body disease, because of the combination of dementia and parkinsonism. Other possibilities discussed in the CPC included Pick's disease, frontotemporal dementia and parkinsonism, and Alzheimer's disease. Post-mortem examination revealed moderate atrophy in the frontal and temporal cortices. Microscopic examination showed atrophy and gliosis in the hippocampus. Many diffuse plaque and neuritic plaques were seen in the frontal cortex by methenamine silver staining. Neurofibrillary tangles were also found. The Meynert nucleus was preserved. The putamen and the substantia nigra were also intact. Pathologic diagnosis was consistent with Alzheimer's disease.

Aged↗

Predominant activation of I1-waves from the leg motor area by transcranial magnetic stimulation.

We performed transcranial magnetic stimulation (TMS) to elucidate the D- and I-wave components comprising the motor evoked potentials (MEPs) elicited from the leg motor area, especially at near-threshold intensity. Recordings were made from the tibialis anterior muscle using needle electrodes. A figure-of-eight coil was placed so as to induce current in the brain in eight different directions, starting from the posterior-to-anterior direction and rotating it in 45 degrees steps. The latencies were compared with those evoked by transcranial electrical stimulation (TES) and TMS using a double cone coil. Although the latencies of MEPs ranged from D to I3 waves, the most prominent component evoked by TMS at near-threshold intensity represented the I1 wave. With the double cone coil, the elicited peaks always represented I1 waves, and D waves were evoked only at very high stimulus intensities, suggesting a high effectiveness of this coil in inducing I1 waves. Using the figure-of-eight coil, current flowing anteriorly or toward the hemisphere contralateral to the recorded muscle was more effective in eliciting large responses than current flowing posteriorly or toward the ipsilateral hemisphere. The effective directions induced I1 waves with the lowest threshold, whereas the less effective directions elicited I1 and I2 waves with a similar frequency. Higher stimulus intensities resulted in concomitant activation of D through I3 waves with increasing amount of D waves, but still the predominance of I1 waves was apparent. The amount of I waves, especially of I1 waves, was greater than predicted by the hypothesis that TMS over the leg motor area activates the output cells directly, but rather suggests predominant transsynaptic activation. The results accord with those of recent human epidural recordings.

Electric Stimulation↗

Indications and technique of sentinel lymph node biopsy in breast cancer using 99m-technetium labeled tin colloids.

BACKGROUND: The status of the sentinel lymph node (SLN) can reflect the status of other lymph nodes in breast cancer. The efficacy of dye injection and radiolabeled tin colloids for the accurate identification of the SLN was investigated. The indications for SLN biopsy for determining clinical nodal status were also investigated. METHODS: A total of 108 patients with breast cancers less than 5 cm were enrolled. Ninety-six patients were clinically node negative and 12 were node positive. About 2 hours before surgery, 1 to 2.5 ml of 99m-technetium-labeled tin colloid was injected around the tumor. Just before the operation, dye was also injected into the tissue surrounding the tumor. Six clinically node negative patients were omitted from the dye-injection process. The SLN was identified as a lymph node with extremely high radioactivity using a gamma probe or a gamma counter. Complete axillary dissection was performed and the metastatic status investigated by hematoxylin and eosin staining. RESULTS: In clinically node negative patients undergoing dye-injection, the SLN was identified in 89 of 90 patients (98.9%), and there was only one patient with lymph node metastasis outside the SLN. However, in clinically node positive patients undergoing dye-injection, the identification rate of the SLN was 66.7% (8 of 12 patients) and there was one patient with lymph node metastasis outside the SLN (12.5%). Without dye-injection, the SLN could be detected in 4 of 6 patients (66.7%). CONCLUSIONS: Successful identification of the SLN with tin colloid requires concomitant dye-injection and candidates for SLN biopsy should be restricted to clinically node negative cases.

Adult↗