Biomedical subjects

S Noguchi

Publications and source records attributed to S Noguchi.

At least 271 records · Page 15Linked to original sources

PubMed1996

Growth of cultured human bronchiogenic epithelioid CCD-14 Br cells and dermal fibroblasts, NB1 RGB treated with ginseng tetrapeptide and its isomer.

The configurations of the component amino acids in ginseng tetrapeptide 1 isolated from Panax ginseng were determined by HPLC with an optical resolution column and the structure of 1 was established to be H-L-Val-gamma-D-Glu-D-Arg- Gly-OH. Synthesis of the ginseng tetrapeptide, 1, and of the configuration and conjugation isomers, H-L-Val-gamma-L-Glu-L-Arg-Gly-OH (2), H-L-Val-D-Glu- D-Arg-Gly-OH (3), and H-L-Val-L-Glu-L-Arg-Gly-OH (4) was carried out by a solid-phase method using the Fmoc strategy. The effects of 1-4 on the proliferation of baby hamster kidney (BHK)-21 cells, normal female bronchiogenic epithelioid (CCD-14 Br) cells, and normal human epidermal fibroblast (NB1 RGB) were examined. Only 1 showed 32 and 23% enhancement of BHK-21 and human CCD-14 Br cells growth, respectively, at a concentration of 13.6 microM and 41% enhancement of NB1 RGB cells growth at a concentration of 32 microM under the conditions employed. It was shown that both the configuration of the component amino acids and the peptide conjugation at a gamma-position of D-Glu in 1 are important for proliferation of the cells. Compound 1 exerted a prominent effect on cell stimulation and growth rate without any morphological change and showed no cytotoxicity.

Amino Acid Sequence↗

PubMed1996

Mutations that disrupt the carboxyl-terminus of gamma-sarcoglycan cause muscular dystrophy.

Recently, mutations in the genes encoding several of the dystrophin-associated proteins have been identified that produce phenotypes ranging from severe Duchenne-like autosomal recessive muscular dystrophy to the milder limb-girdle muscular dystrophies (LGMDs). LGMD type 2C is generally associated with a more severe clinical course and is prevalent in northern Africa. A previous study identified a single base pair deletion in the gene encoding the dystrophin-associated protein gamma-sarcoglycan in a number of Tunisian muscular dystrophy patients. To investigate whether gamma-sarcoglycan gene mutations cause autosomal recessive muscular dystrophy in other populations, we studied 50 muscular dystrophy patients from the United States and Italy. The muscle biopsies from these 50 patients showed no abnormality of dystrophin but did show diminished immunostaining for the dystrophin-associated protein alpha-sarcoglycan. Four patients with a severe muscular dystrophy phenotype were identified with homozygous, frameshifting mutations in gamma-sarcoglycan. Two of the four have microdeletions that disrupt the distal carboxyl-terminus of gamma-sarcoglycan yet result in a complete absence of gamma-and beta-sarcoglycan suggesting the importance of this region for stability of the sarcoglycan complex. This region of gamma-sarcoglycan, like beta-sarcoglycan, has a number of cysteine residues similar to those in epidermal growth factor cysteine-rich regions.

Amino Acid Sequence↗

PubMed1996

Genomic screening for beta-sarcoglycan gene mutations: missense mutations may cause severe limb-girdle muscular dystrophy type 2E (LGMD 2E).

Autosomal recessive limb-girdle muscular dystrophies (LGMDs) are genetically heterogeneous. A subgroup of these disorders is caused by mutations in the dystrophin-associated sarcoglycan complex. Truncating mutations in the 43 kDa beta-sarcoglycan gene (LGMD 2E) were originally identified in a sporadic case of Duchenne-like muscular dystrophy, and a common missense mutation (T151R) was identified independently in Indiana Amish pedigrees with a milder form of LGMD. To facilitate mutational analysis of larger numbers of patients directly from genomic DNA, as opposed to reverse transcribed RNA from muscle biopsies, we have determined the genomic structure of the beta-sarcoglycan gene. The open reading frame of the beta-sarcoglycan coding region extends over six exons. Primers were designed for PCR amplification of single exons from genomic DNA and subsequent single strand conformation polymorphism (SSCP) analysis. We screened 15 patients from the Brazilian LGMD patient population, 13 of whom followed a severe course. Most of the patients had been assessed previously for deficiency of alpha-sarcoglycan immunofluorescence on muscle biopsy sections as a marker for disease of the sarcoglycan complex. Novel mutations in two familial and two sporadic cases of severe childhood-onset LGMD were identified. Only one of these patients carried a truncating mutation (homozygous 2 bp deletion, FS164TER), while the other three carried missense mutations (homozygous R91P, homozygous M100K, heterozygous recessive L108R; only one allele could be identified in this family). All three missense mutations occurred in exon 3, coding for the immediate extracellular domain. Complete absence for all three of the known sarcoglycans was noted by immunohistochemistry on muscle biopsy sections of the patients.

Amino Acid Sequence↗

PubMed1996

Immunohistochemical characterization of hepatic lymphocytes in acute hepatitis A, B, and C.

The distinctive histologic findings in acute hepatitis A, B, and C suggest that different immunological mechanisms are involved in the pathogenesis of these diseases. This study was undertaken to define the immune response in each type of acute hepatitis by identification of the intrahepatic lymphocyte subsets. Thirty paraffin-embedded liver biopsy specimens from 10 patients with acute hepatitis A, 10 patients with acute hepatitis B, and 10 patients with acute hepatitis C were evaluated. Immunohistochemical staining was performed by the indirect immunoperoxidase technique using the following monoclonal or polyclonal antibodies: CD45RO, CD20-cy, CD57, and Mac387. Inflammatory infiltrates varied from specimen to specimen. However, CD45RO+ memory T cells were the predominant infiltrating mononuclear cells in all specimens. In the portal areas, CD45RO+ memory T cells were the most prominent in AHC, followed by AHA and AHB, and the difference between AHC and AHB was statistically significant. CD20-cy+ B cells were seen mainly in the portal areas, and were significantly less common in AHB than in AHA and AHC. In addition, the ratio of CD20-cy+ B cells to CD45RO+ memory was significantly lower in AHB than in the other types of acute hepatitis. The necrotic areas in all specimens contained mainly CD45RO+ memory cells in association with a few CD57+ NK and T cells or CD20-cy+ B cells. Our study revealed differences of the intrahepatic lymphocyte subsets among the various types of acute hepatitis, but the meaning of these differences is presently unknown. Therefore, further studies are required to fully elucidate the mechanism of the immune response in acute hepatitis.

Acute Disease↗

PubMed1996

Sequence variation of the hypervariable region in HCV carriers with normal ALT levels: a comparison with symptomatic carriers.

The clinical significance of the hypervariable region (HVR) in the N-terminus of the E2/NS1 region, which encodes the putative envelope glycoprotein (gp 70) of HCV, has not yet been elucidated. We studied the relation between HVR changes and elevation of the alanine aminotransaminase (ALT) level due to liver cell injury as well as the persistence of HCV infection. Three patients (carrier group) who were HCV RNA positive and had normal ALT levels for as long as five years and three patients with high ALT levels were studied. None of the six patients had a history of treatment. HCV RNA was extracted from serum obtained from each patient in 1990 and 1995. The E2/NS1 region, including HVR-1 and HVR-2, was amplified using the RT-PCR method. PCR products were cloned and nucleotide sequences were determined using the dideoxynucleotide chain termination method. No clear correlation was found between the ALT levels and the number of nucleotide substitutions in HVR-1. The number of nucleotide substitutions in HVR-1 during the five years was greater than in other regions. Furthermore, more nucleotide substitutions occurred in the 1st and 2nd codon positions of HVR-1 than in the control region, even in the carrier group. In conclusion, HVR-1 changes are probably a more important factor in persistent viral infection than liver cell injury.

Aged↗

PubMed1996

Second primary neoplasms in thyroid cancer patients.

To determine risk patterns for second primary neoplasms after the occurrence of thyroid cancer, we conducted a retrospective cohort study of 3321 thyroid cancer patients who were operated and histologically confirmed at the Noguchi Thyroid Clinic and Hospital Foundation between 1946 and 1985. They were followed from the date of operation through the end of 1990 with an observation period from 45 to 5 years. The average observation period of the patients was 13.4 years and the follow-up rate reached 98%. The standardized mortality ratio (SMR) was computed to assess possible risk increase by cancer site. In this computation, the time period less than 5 years after operation was omitted to reduce the influence of deaths related to the original thyroid cancer. A total of 103 deaths from malignant neoplasms other than thyroid cancer were observed during this time period (SMR = 1.6, 95% confidence interval [CI] = 1.3-2.0). Analyses of site-specific cancer mortality revealed significantly elevated risks for the central nervous system (SMR = 16.1, CI = 5.2-37.6) and respiratory organs (SMR = 2.6, CI = 1.5-4.1). Based on a review of available medical records with histological findings, we concluded that the risk increases for these sites were most likely to be attributable to second primary neoplasms. Whether or not the patients had received radiotherapy was not significantly associated with elevated risk. Further investigations are needed to clarify the risk factors responsible for the above findings.

Adolescent↗

PubMed1996

Detection of gastric cancer micrometastases in lymph nodes by amplification of keratin 19 mRNA with reverse transcriptase-polymerase chain reaction.

A sensitive method for the detection of gastric cancer micrometastases in lymph nodes was developed. The method was based on amplification of keratin 19 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR). Keratin 19 RT-PCR showed that keratin 19 mRNA was expressed in all 12 gastric cancers, but not in any of 20 normal control lymph nodes, indicating that keratin 19 mRNA is a good target of RT-PCR for the detection of gastric cancer micrometastases in lymph nodes. Serial dilution studies of RNA extracted from gastric cancers against RNA extracted from control lymph nodes demonstrated that the detection sensitivity of the keratin 19 RT-PCR method was one cancer cell in 10(3)-10(5) lymph node cells. Detectability of lymph node metastases was compared between keratin 19 RT-PCR and conventional histological examination, using 100 lymph nodes obtained from 12 gastric cancer patients. Keratin 19 mRNA was detected in all of the seven lymph nodes which were histologically metastasis-positive. Of the 93 lymph nodes which were histologically metastasis-negative, 79 were found not to express keratin 19 mRNA but 14 were found to express keratin 19 mRNA, indicating that these lymph nodes contained micrometastases which could not be detected by histological examination. These results demonstrate that keratin 19 RT-PCR is a more sensitive method than histological examination for the detection of gastric micrometastases in lymph nodes.

Adult↗

PubMed1996

Higher elimination rate of hepatitis C virus among women.

The mortality rate from liver disease in H town of the Fukuoka prefecture in Japan is significantly higher in men than in women. To clarify the gender-related difference, we evaluated subjects with hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in the S area of this town. A total of 824 adults participated in this study, 332 men and 492 women. The incidence of positivity for hepatitis B surface antigen (HBsAg) in serum did not differ significantly between the subjects in the S area (1.9%) and Japanese blood donors (1.5%); however, the incidence of positivity for serum antibody to hepatitis C virus (HCVAb) in the subjects (31.8%) greatly exceeded that in Japanese blood donors (1.3%). The rate of positivity for HCVAb did not differ significantly between men (28.3%) and women (34.1%), but the proportion of serum HCV RNA-positive to HCVAb-positive subjects was significantly higher in men (78.2% in men vs 67.3% in women). The incidence of elevated serum alanine aminotransferase (ALT) in subjects positive for serum HCV RNA was also significantly higher in men (77.0% in men vs 55.8% in women). These results suggest that a more frequent elimination of HCV from serum in women may explain the observed lower mortality from liver disease.

Adult↗

PubMed1996

Oncofetal expression of blood group-related antigen on morules in thyroid carcinoma.

Morule formation in association with characteristic biotinrich 'optically clear nuclei' were found in 7 of 2514 cases of thyroid carcinoma. The seven patients were all young females aged from 20 to 36 years who were suffering from either papillary carcinoma (six cases) or follicular carcinoma (one case). The ABH (O) blood group (BG) types were A in three, AB in two and H(O) in two patients. Immunohistochemical study revealed that ABH(O) and Lewis BG antigens were expressed more specifically on morules than on ordinary neoplastic cells of papillary or follicular carcinoma. Lewis BG antigens tested in the present study were as follows: CA50, CA19-9, stage-specific embryonic antigen 1 (SSEA-1), and sialyl SSEA-1. Ulex europaeus agglutinin I (UEA-I) histochemistry showed a positive reaction on all the morules of blood groups A and H(O) patients, but yielded completely negative results on the morules of type AB patients. Sequential digestion by neuraminidase and alpha-galactosidase unmasked the reactivity for UEA-I even on the morules of type AB patients. The consistent reactivity for UEA-I on the morules seemed to be related to specific expression of BG antigens, which were characterized as oncofetal expression. It is suggested that the morules in thyroid carcinoma might be a kind of fetal component induced by the differentiation of the neoplastic cells to the stage of immature embryonic cells.

Adenocarcinoma, Follicular↗

PubMed1996

Insular component as a risk factor of thyroid carcinoma.

Forty-four thyroid carcinomas with an insular component (IC) were reviewed from 2457 tumors diagnosed as papillary (PC) or follicular carcinoma (FC). These tumors were classified as FC with an IC (FCIC; 30 cases) and PC with an IC (PCIC; 14 cases). Both tumors were composed of solid cell nests in some areas and had a tendency toward a characteristic nuclear size: FCIC had a small nucleus and PCIC contained a nucleus of an intermediate type or a large nucleus similar to that of PC, although there were numerous tumors with an exceptional nuclear size. The mean age and tumor diameter were the highest and largest in FCIC, respectively, followed by PCIC. Among the 44 cases, 17 patients died of the disease, two were alive with the disease and 18 were alive without the disease. From 13 clinicopathological factors, the presence of an IC, age, non-encapsulation, tumor size, vascular invasion and necrosis were found to be independent variables for actual prognosis of FC and PC based on univariate analysis followed by multivariate analysis. The results of the present study indicate that the presence of an IC is an independent aggressive prognostic factor for patients with PC and FC.

Adenocarcinoma, Follicular↗

PubMed1996

Effects of weight loss on bone mineral density in rats.

OBJECTIVE: To evaluate the effects of weight loss on bone mineral density (BMD). METHODS: Eight-week-old female rats were divided into 4 groups: Those in Group A received a restricted diet for 4 weeks; those in Group B received a restricted diet and were treated with estrogen; those in Group C were castrated; and those in Group D underwent sham operations. The rat's body weight (BW) and vaginal smears were checked, and their femoral BMD was measured. RESULTS: The BW and BMD at 12 weeks were lower in Groups A and B than in Groups C and D; thereafter, however, these values increased for Groups A and B, but were still lower than those in Group D even at 20 weeks. In Group C, the BMD did not decrease, but it was significantly lower than that in Group D at 16 and 20 weeks. Group A showed continuous diestrus 2 weeks after dietary restriction began, but recovered to a 4-day cycle 2 weeks after the initiation of free food consumption. CONCLUSION: Weight loss had a greater effect on BMD than hypoestrogenism.

Animals↗

PubMed1996

The induction of a biphasic bronchospasm by the ETB agonist, IRL 1620, due to thromboxane A2 generation and endothelin-1 release in guinea-pigs.

1. IRL 1620 (0.01-0.1 mg kg-1, i.v.), a selective endothelin B (ETB) receptor agonist, induced a dose-dependent biphasic increase in total lung resistance and a decrease in dynamic compliance in anaesthetized and artificially ventilated guinea-pigs. After intravenous injection of IRL 1620 (0.03 mg kg-1), the first phase was observed within 2 min whereas the second phase started between 5 and 10 min after injection and was long lasting. 2. In order to characterize which endothelin receptors are involved in both phases of bronchoconstriction, we studied the effect of ETA and ETB receptor antagonists (BQ 123 and BQ 788, respectively). BQ 788 (0.1-1 mg kg-1, i.v.) inhibited, in a dose-dependent manner, both phases of bronchoconstriction. BQ 123 (3 mg kg-1, i.v.) markedly inhibited (by 76%) the second phase of bronchoconstriction but had no effect on the early component of the response. 3. The effect of atropine, neurokinin-I (NK1) and neurokinin-2 (NK2) receptor antagonists (SR140333 and SR48968, respectively) were tested to investigate the possible involvement of cholinergic and sensory nerve activation, respectively, in the response to IRL 1620. Likewise, the role of arachidonic acid metabolites (leukotriene D4 antagonist, ONO-1078 and thromboxane A2 (TXA2) inhibitor, OKY-046) in this response was also investigated. OKY-046 (1 mg kg-1, i.v.) and atropine (1 mg kg-1, i.v.) partially inhibited the first phase (by 80% and 20%, respectively) without affecting the late phase of bronchoconstriction. Neither ONO-1078 (1 mg kg-1, i.v.) nor the combination of SR140333 (0.2 mg kg-1, i.v.) and SR 48968 (0.2 mg kg-1, i.v.) modified IRL 1620-induced bronchoconstriction. 4. A low dose of IRL 1620 (0.005 mg kg-1, i.v.) induced a monophasic bronchoconstriction. Pretreatment by phosphoramidon (100 mumol kg-1, i.v.) restored the second phase of bronchoconstriction. In this condition, BQ 123 (3 mg kg-1, i.v.) was able to inhibit partially the second phase of bronchoconstriction. 5. These results suggest that both phases of bronchoconstriction induced by IRL 1620 were mediated primarily by ETB receptor activation, the first phase being a consequence of TXA2 and acetylcholine release. The inhibition by an ETA receptor antagonist and the restoration by a neutral endopeptidase (NEP) inhibitor of the second phase of bronchoconstriction suggests that primary activation of ETB receptors leads to autocrine/paracrine endothelin-1 (ET-1) release that would subsequently cause profound bronchoconstriction through both ETA and ETB receptor activation.

Animals↗

PubMed1996

Differential expression of dipeptidyl peptidase IV (CD26) and thyroid peroxidase in neoplastic thyroid tissues.

This paper reports the results of research to examine the possibility of using the differential expression of two enzymes, dipeptidyl peptidase IV (DPPIV/CD26, EC: 3.4.14.5) and thyroid peroxidase (TPO, EC: 1.11.1.7), as histochemical markers histopathologically to diagnose thyroid carcinomas. The research is based on previous reports that DPPIV/CD26 is overexpressed in differentiated thyroid carcinoma tissues, and that TPO activity is very low in thyroid carcinoma tissues. Differential expression of the two enzymes in 32 thyroid tissues of various thyroid diseases was studied by Northern blot analysis and histochemical analysis. On Northern blot analyses, all 14 differentiated thyroid carcinomas (11 papillary carcinomas and 3 follicular carcinomas) overexpressed DPPIV/CD26 mRNA, whereas all 17 benign thyroid tissues (4 normal thyroid tissues, 4 Graves' diseases, 2 adenomatous goiters and 7 follicular adenomas) showed faint mRNA expression of DPPIV/CD26. All 17 benign thyroid tissues expressed high levels of TPO mRNA, whereas all 11 papillary carcinomas strongly underexpressed TPO mRNA. Histochemically, all 17 benign tissues were DPPIV/CD26 negative and strongly TPO positive, while all 11 papillary carcinomas were strongly DPPIV/CD26 positive and TPO negative. Two of 3 follicular carcinomas were histochemically positive for the two enzymes. A medullary carcinoma did not show any mRNA expression of either enzyme. These results suggest that the differential expression of these two enzymes can be applied to study the thyroid tumorigenesis.

Adenocarcinoma, Follicular↗

PubMed1996

c-myc expression is associated with increased proliferation activity in thyroid follicular cells of Graves' disease as stimulated by autoantibodies.

Expression on thyroid follicular cells of HLA-DR, c-myc protein and proliferating cell nuclear antigen (PCNA) was examined immunohistochemically in 28 cases of Graves' disease (GD) and in 29 cases of Hashimoto's thyroiditis (HT). Immunoreactivity for PCNA in GD was seen not only in follicular cells adjacent to a lymphocytic infiltration, where the follicular cells were positive for HLA-DR, but also in hyperplastic follicular cells without the infiltration. The distribution of expressed c-myc protein was similar to that of PCNA in GD but not in HT. Semiquantitatively graded degrees of lymphocytic infiltration and expression of HLA-DR, c-myc and PCNA in GD showed a high correlation with one another. However, the degrees of c-myc expression in HT showed no significant correlation with any other degrees. Intraperitoneal injection of bovine TSH or of immunoglobulins derived from a patient with GD in rabbits induced hyperplastic change of thyroid follicular cells, as reflected in PCNA and c-myc immunoreactivity, as well as strong peroxidase and acid phosphatase activity. Immunization with synthesized peptide of thyrotropin receptor also exhibited the same results in the rabbit thyroids. Our results indicate that c-myc expression on follicular cells of GD may reflect a stimulation by autoantibodies mediated through the thyrotropin receptor.

Adolescent↗

PubMed1996

Posterior fusion for odontoid fracture in an infant--case report.

A 2-year-3-month-old girl presented with a rare displaced odontoid fracture. She was managed nonoperatively by manipulation followed by 3-month extracorporeal fixation with a halo brace. However, lateral radiography revealed recurrent dislocation at the base of the odontoid process. Magnetic resonance imaging demonstrated a "synchondrotic slip." She therefore underwent posterior wiring with iliac bone grafting to prevent pseudoarthrosis. The odontoid process had fused to the axis at 4 months postoperatively. Surgical management should be considered as a treatment method for pediatric odontoid fracture because of the difficulties in maintaining long-term immobilization and confirming the union.

Child, Preschool↗

PubMed1996

Detection of breast cancer micrometastases in axillary lymph nodes by means of reverse transcriptase-polymerase chain reaction. Comparison between MUC1 mRNA and keratin 19 mRNA amplification.

Usefulness of MUC1 mRNA and keratin 19 mRNA as a target of reverse-transcriptase polymerase chain reaction (RT-PCR) was compared in the detection of breast cancer micrometastases in axillary lymph nodes. RT-PCR amplification of MUC1 mRNA and keratin 19 mRNA was conducted using total RNA samples. RT-PCR products were stained with ethidium bromide and analyzed by agarose gel electrophoresis. Expression of both MUC1 mRNA and keratin 19 mRNA was detected by RT-PCR in a breast cancer cell line (MRK) and in all the 23 primary breast cancers but not in the control lymph nodes obtained from patients with benign diseases. A serial dilution study of MRK cells against normal lymph node cells has shown that detection sensitivity of MUC1 RT-PCR and keratin 19 RT-PCR were 1/10(5) and 1/10(6) (cancer/lymph node cells), respectively. Sixty-three axillary lymph nodes were obtained from 23 patients with primary breast cancer, and metastases in each lymph node were investigated by histological examination (hematoxylin and eosin sections) and RT-PCR method. In all 10 lymph nodes, which were histologically metastasis-positive, both MUC1 mRNA and keratin mRNA were detected by RT-PCR. Of the 53 histologically negative lymph nodes, 3 (6%) and 5 (9%) lymph nodes were found to express MUC1 mRNA and keratin 19 mRNA, respectively, indicating the presence of micrometastases which could be detected by RT-PCR but not by histological examination. These results demonstrate the usefulness of both MUC1 RT-PCR and keratin 19 RT-PCR in the detection of breast cancer micrometastases in lymph nodes, and also indicate the superiority of keratin 19 RT-PCR over MUC1 RT-PCR because of its higher detection sensitivity.

Axilla↗

PubMed1996

Prognostic significance of Ki-67 labeling index in urothelial tumors of the renal pelvis and ureter.

PURPOSE: We evaluated the prognostic significance of the Ki-67 labeling index in 70 patients with primary urothelial tumors of the renal pelvis and ureter. MATERIALS AND METHODS: Immunohistochemical staining for Ki-67 in archival tumor materials was done by the streptavidin-biotin method. RESULTS: Univariate survival analysis showed that the prognosis of patients with a high Ki-67 labeling index of 21.7 or more was significantly worse than that of patients with an intermediate labeling index of 13.3 to less than 21.7 (p < 0.01) or a low labeling index of less than 13.3 (p < 0.001). Multivariate survival analysis showed that staining for Ki-67 labeling index was significantly correlated with prognosis (p < 0.01). CONCLUSIONS: Analysis of Ki-67 labeling index provides useful prognostic information about patients with primary urothelial tumors of the renal pelvis and ureter.

Antigens, Neoplasm↗

PubMed1996

Technetium-99m-sestamibi scintigraphy compared with thallium-201 in evaluation of thyroid tumors.

UNLABELLED: Technetium-99m methoxyisobutylisonitrile (MIBI) is a myocardial perfusion imaging agent that has been reported to effectively localize in various tumors (e.g., lung and thyroid carcinomas and osteogenic sarcoma). To determine its usefulness in thyroid tumors, we compared 99mTc-MIBI with 201TI imaging. METHOD: We evaluated 25 patients with thyroid tumors (papillary carcinoma in 11, follicular carcinoma in 2, follicular adenoma in 7, adenomatous goiter in 5). Fifteen metastatic lesions from differentiated thyroid carcinomas were also evaluated. Early (10 min after injection) and delayed images (120 min after injection) were obtained for both 99mTc-MIBI and 201TI scintigraphy. RESULTS: The early images showed very similar findings for both 99mTc-MIBI and 201TI. However, the delayed images showed that malignant tumors tended to retain more tracer agent than benign nodules. Marked retention was in 61.5% (8 of 13) of 201TI images and 53.8% (7 of 13) of 99mTc-MIBI images. For metastatic lesions from thyroid carcinomas, the findings for 99mTc-MIBI imaging were nearly identical to those for 201TI imaging. A slight difference in clarity was seen that may have been due to the effect of the 99mTc. CONCLUSION: Although 99mTc-MIBI scintigraphy does not have particularly good results in differentiating malignant from benign thyroid tumors, it may be useful in evaluating metastases or predicting recurrence because of its better imaging characteristics.

Adenocarcinoma, Follicular↗