Shin-ichiro Takai

INTERNAL FISTULA AS A ROUTE OF INFECTION IN ACUTE SUPPURATIVE THYROIDITIS

Seven cases of acute suppurative thyroiditis are described. Six patients had a recurrent painful swelling of the left anterior neck and one was seen at her first episode of the disease. A barium meal revealed a fistula originating from the apex of the left pyriform sinus in all cases. The fistula, a remnant of the fourth pharyngeal pouch, thus seems to be a common route of infection in acute suppurative thyroiditis, allowing bacterial infection to begin in the perithyroidal space and spread to the thyroid gland. Complete extirpation of the fistula is required for a permanent cure.

p53 Gene Mutations Associated with Anaplastic Transformation of Human Thyroid Carcinomas

Anaplastic carcinoma of the thyroid gland, which is one of the most aggressive, malignant tumors in humans, is considered to originate from preexisting differentiated thyroid cancer. To define the genetic alterations associated with such progression, we examined nine cases of anaplastic thyroid carcinoma for mutation in exons 4–9 of the p53 tumor suppressor gene. Preliminary screening for mutation by RNase protection analysis demonstrated that two out of nine anaplastic carcinomas contained sequence alterations in the p53 gene. Subsequent DNA sequencing identified the mutated nucleotides in these two cases; one was a nonsense mutation at codon 165, and the other was a single‐base deletion at codon 176 resulting in the creation of a stop codon downstream due to frameshift. The fact that no mutations were detected in coexisting foci of papillary carcinomas from the same patients shows that these mutations of the p53 gene occurred after development of papillary carcinomas. These results suggest that p53 gene mutation triggers the progression from differentiated into anaplastic carcinoma in the human thyroid gland.

Relation of doubling time of plasma calcitonin levels to prognosis and recurrence of medullary thyroid carcinoma.

Plasma calcitonin (CT) levels were measured serially in 54 patients surgically treated for medullary thyroid carcinoma. Patients with postoperative basal CT levels higher than 1 ng/ml measured within 1 month after surgery had a higher recurrence rate than those with lower CT levels (p < 0.002). Patients with postoperative basal CT levels higher than 2 ng/ml had a lower survival rate than those with lower CT levels (p < 0.01). However, pre-operative basal CT levels had no significant correlation with life expectancy or recurrence during the present observation period. Serial measurements in 23 patients with elevated postoperative CT levels showed exponential increases in basal CT levels in 19 patients (p < 0.05 in nine patients, 0.05 < p < 0.1 in four patients) and slight decreases in four (p < 0.05 in one patient). Doubling time of CT levels calculated from the regression line in each patient showed the highest correlation with 3-year survival, recurrence within 5 years, and time interval between surgery and clinical recurrence of the tumor, allowing quantitative prediction of the prognosis.

Comparison of FDG-PET with MIBI-SPECT in the detection of breast cancer and axillary lymph node metastasis.

PURPOSE The purpose of this work was to compare [18F]2-deoxy-2-fluoro-D-glucose (FDG) PET and 99mTc-methoxyisobutylisonitrile (MIBI) SPECT in the detection of breast cancer and axillary lymph node metastasis in the same patients. METHOD FDG-PET and MIBI-SPECT were performed within 3 days for 40 women (age range 25-86 years old) with suspected breast cancer, in whom biopsies and/or mastectomies were performed. Both images were visually assessed, and the count ratio between tumor and normal tissue (T/N ratio) was calculated. RESULTS Thirty-eight patients had breast cancer, and the remaining two had benign breast lesions. The sensitivities of FDG-PET and MIBI-SPECT were 78.9 and 76.3% for breast cancer and 50.0 and 37.5% for axillary lymph node metastasis, respectively. The T/N ratio of breast cancer was significantly higher in FDG-PET (6.01 +/- 3.08 mean +/- SD) than that in MIBI-SPECT (3.48 +/- 1.21) (p = 0.01). Nonmalignant diffuse uptake of FDG in the breasts and the accumulation of MIBI in heart and liver occasionally obscured tumor uptake. CONCLUSION These results indicate that MIBI-SPECT is comparable with FDG-PET in detecting breast cancer. Neither FDG-PET nor MIBI-SPECT is sufficiently sensitive to rule out axillary lymph node metastasis.

Deletion Mapping of Chromosome 1p and 22q in Pheochromocytoma

To identify the localization of tumor suppressor genes, 22 pheochromocytomas (9 hereditary and 13 sporadic) were examined for loss of heterozygosity (LOH) on the short arm of chromosome 1 and on the long arm of chromosome 22 by using 11 polymorphic DNA markers on each chromosome arm. LOH on 1p was observed in 12 of 22 informative cases (55%) and on 22q in 8 of 20 informative cases (40%). There was no significant difference in the frequency of LOH on 1p or 22q between hereditary and sporadic cases. We could localize the commonly deleted regions as distal to D1S73 and proximal to D1S63 on 1p and distal to D22S24 and proximal to D22S1 on 22q. In addition, the relationship between LOH on 1p and 22q was studied in 20 pheochromocytomas which were informative for probes on both chromosome arms. Of eight tumors that showed LOH on 22q, allelic loss on 1p was also detected in seven. Thus, LOH on 22q was correlated significantly with LOH on 1p (P= 0.0249; Fishers exact test). These results suggest that inactivation of multiple tumor suppressor genes may be required for development and progression of hereditary and non‐hereditary pheochromocytoma.

Involvement of the Retinoblastoma Gene in Primary Osteosarcomas and Other Bone and Soft-Tissue Tumors

The retinoblastoma (Rb) gene, thought by some to be associated with tumor formation of retinoblastoma as a recessive human oncogene, was investigated in 57 cases using DNA and RNA from primary osteosarcomas and other bone and soft-tissue tumors. Eight of 23 osteosarcoma cases (35%) showed structural alterations of the Rb gene. Three of the eight demonstrated homozygous deletions, and the remaining five cases showed heterozygous deletions. Seven out of eight cases represented deletion of a 7.5-kb HindIII fragment. Northern blot analysis of five cases of osteosarcoma showed that four demonstrated no detectable Rb gene transcription, and one case had a truncated 3.5-kb fragment with a faint 4.7-kb band. In the other 34 cases of bone and soft-tissue tumors, two cases of three malignant fibrous histiocytomas showed an Rb gene abnormality by Southern blot analysis. These results strongly suggest that Rb gene alteration is pertinent to the tumorigenesis of most osteosarcoma cases and some other bone and soft-tissue tumors.

C CELL CARCINOMA OF THE THYROID

Two cases of papillary type of C cell carcinoma of the thyroid were reported. They showed papillary arrangement with Abrovascular stalk in properly Axed tissues. Histochemically argyrophil reaction was positive in the cytoplasm and amyloid deposited in the stroma. Ultrastructurally secretory granules were found in their cytoplasm. The papillary type is not an artifact but one of the histologic variations of this carcinoma. ACTA PATH. SAP. 29: 653–659, 1979.

A Simple and Useful Method for Simultaneous Screening of Elevated Levels of Expression of a Variety of Oncogenes in Malignant Cells

Abnormal expression of various oncogenes has been implicated in the development of many malignant tumors. Although RNA blotting methods have been used to measure abnormal expression, they involve the time‐consuming process of individually labeling the oncogene probes. To simplify this process we have attempted to develop a new method, termed simultaneous screening, which is based on the synthesis of radiolabeled cDNA corresponding to the mRNA population of malignant cells and on hybridization with various oncogene probes, immobilized on a membrane filter. This method circumvents the time‐consuming process of the prevailing RNA blotting methods and is also sensitive enough to detect accurately a five‐ to ten‐fold level of expression of rare mRNA (∼10 copies per cell). Overexpression of ten oncogenes was detected in a variety of malignant cells and mitogen‐stimulated cells with this method. These results suggest that our simultaneous screening method can be used to examine the overexpression of oncogenes.

High proportion of missense mutations of the BRCA1 and BRCA2 genes in Japanese breast cancer families

AbstractMutations in either of two recently identified genes, BRCA1 and BRCA2, are thought to be responsible for approximately two-thirds of all cases of autosomal-dominantly inherited breast cancer. To examine the nature and frequency of BRCA1 and BRCA2 mutations in Japanese families exhibiting a high incidence of breast cancer, we screened 78 unrelated families in this category for mutations of these two genes. Examining the entire coding sequences as well as exon–intron boundaries of both genes by polymerase chain reaction (PCR) single-strand conformation polymorphism (SSCP) and multiplex-SSCP analysis, we identified possible disease-causing alterations in BRCA1 among affected members of 15 families and in BRCA2 in another 14 families. In 15 of those 29 families, the affected individuals carried missense mutations, although most germline mutations reported worldwide have been deletions or nonsense mutations. Our results, indicating that missense mutations of BRCA1 and BRCA2 tend to predominate over frameshifts or nonsense mutations in Japanese breast cancer families, will contribute signifi-cantly to an understanding of mammary tumorigenesis in Japan, and will be of vital importance for future genetic testing.

Incidence of Prominent Corneal Nerves in Multiple Endocrine Neoplasia Type 2A

We studied the increased visibility of corneal nerves inside an 8-mm diameter central corneal area in 14 patients with multiple endocrine neoplasia type 2A, one patient with multiple endocrine neoplasia type 2B, five patients with nonhereditary medullary thyroid carcinoma, ten patients with anterior keratoconus, and ten normal subjects. We used a grading system (grade 0 through grade 4) for nerve visibility based on slit-lamp biomicroscopic examination and photographic documentation. All 20 normal eyes showed either grade 0 or grade 1, which indicated no pathologic thickening of corneal nerves. Sixteen of the 28 eyes (57%) with multiple endocrine neoplasia type 2A, however, were evaluated as grade 2 or higher, which indicated thickened corneal nerves. The incidence of high nerve visibility in eyes with multiple endocrine neoplasia type 2A was significantly greater compared to normal eyes (P less than .0001), anterior keratoconus (P less than .0001), and nonhereditary medullary thyroid carcinoma (P = .0012). Furthermore, eight of the 28 eyes (29%) with multiple endocrine neoplasia type 2A showed markedly prominent corneal nerves (grade 3 and 4), a prominence similar to those seen in eyes with multiple endocrine neoplasia type 2B. There was no definite relationship among prominent nerve, age of the patient, and occurrence of pheochromocytoma. These findings suggest that over half of all patients with multiple endocrine neoplasia type 2A show corneal nerves pathologically thickened to different degrees.