Kazuyoshi Kunitomo

Status of c-erbB-2 in gastric adenocarcinoma: a comparative study of immunohistochemistry, fluorescence in situ hybridization and enzyme-linked immuno-sorbent assay.

c‐erb‐2 amplification and overexpression are currently attracting a great deal of attention because a new adjuvant therapy using an antibody against the c‐erbB‐2 gene product, trastuzumab (Herceptin; Genentech, Inc., South San Francisco, CA), has proved effective in treating breast cancer with amplification and/or overexpression of c‐erbB‐2. Aberrations of c‐erbB‐2 have also been detected in ovarian, endometrial and gastric carcinomas at varied frequencies. Amplification of the c‐erbB‐2 locus (17q12‐q21.32), overexpression of c‐erbB‐2 protein (p185) and serum levels of soluble c‐erbB‐2 protein fragments (p105) were examined in gastric cancer patients using fluorescence in situ hybridization (FISH), immunohistochemistry and enzyme‐linked immunosorbent assay (ELISA), respectively. Overexpression of c‐erbB‐2 protein was found in 29 (8.2%) of the 352 gastric carcinomas analyzed. In FISH analysis, all tumors with 3+ immunostaining and 1 of 5 tumors with 2+ staining showed high‐level amplification of c‐erbB‐2. Pre‐operative serum p105 was quantified in serum specimens from 129 patients with gastric cancer and 28 patients with benign diseases. There were no significant differences in the serum p105 levels among 11 patients with c‐erbB‐2‐overexpressing carcinomas, 118 patients with c‐erbB‐2 non‐overexpressing carcinomas and 28 controls, although a single case of gastric carcinoma overexpressing c‐erbB‐2 with extensive liver metastasis had a higher level than the cut‐off value. The mechanisms of overexpression of p185 and high‐level amplification of c‐erbB‐2 in gastric adenocarcinomas seem similar to those well‐established in breast cancers. Patients having gastric adenocarcinoma with c‐erbB‐2 amplification are potential candidates for a new adjuvant therapy using humanized monoclonal antibody.

Protein overexpression and gene amplification of HER-2 and EGFR in colorectal cancers: an immunohistochemical and fluorescent in situ hybridization study

Overexpression of HER-2 and the epidermal growth factor receptor (EGFR) has been observed in many cancers, sometimes accompanied by gene amplification. To assess whether novel chemotherapies targeting these overexpressed proteins may be effective for the treatment of colorectal cancers, we examined the exact frequency of HER-2 and EGFR overexpression, the relationship between gene amplification and protein expression, and the heterogeneity of gene amplification within and between primary and metastatic tumors. We evaluated 244 colorectal cancers immunohistochemically. All tumors found to overexpress HER-2 or EGFR were further analyzed for gene amplification by fluorescent in situ DNA hybridization. Overexpression of HER-2 and EGFR was found in 8 (3%) and 19 (8%) of the 244 colorectal carcinomas, respectively. Gene amplification was observed in 100 and 58% of the tumors exhibiting HER-2 and EGFR overexpression, respectively. HER-2 amplification in cancer cells was characterized by clusters of hybridization signals, suggesting amplicons in homogeneously staining regions that were predominant in most primary and metastatic tumors. EGFR amplification, observed as scattered signals reminiscent of amplicons in double minute chromosomes, or coamplification of EGFR with the centromeric regions was observed as a minor population within primary tumors, and found in variety of populations in metastatic tumors. Overexpression of HER-2 and EGFR were observed in only a small fraction of colorectal carcinomas, but were frequently accompanied by gene amplification.

Expression of epidermal growth factor receptor in gastric carcinomas.

BACKGROUND & AIMS Epidermal growth factor receptor belongs to the family of type I receptor tyrosine kinases. Overexpression of epidermal growth factor receptor has been observed in a variety of cancers with or without amplification of the gene. Novel chemotherapies targeting receptor tyrosine kinases might be effective for the treatment of cancers in which overexpression of this protein is a feature. The aim of this study was to assess the potential efficacy of epidermal growth factor receptor-targeted therapy in gastric cancer. This was achieved by determining the frequency of increased epidermal growth factor receptor expression in gastric cancers and investigating the relationship between protein overexpression and gene amplification. METHODS Immunohistochemical evaluation of 413 gastric cancers was carried out by using a monoclonal antibody to the epidermal growth factor receptor. The intensity of reactivity was scored by using a 4-tier system (negative, 1+, 2+, and 3+). All positive staining (>1+) tumors overexpressing the protein were then analyzed for gene amplification by fluorescence in situ hybridization by using a gene-specific probe. RESULTS High levels of overexpression (2+ or 3+ staining) were found in 9 of 413 (2.2%) patients, whereas low levels of overexpression (1+) were found in 34 (8.2%) of the study cohort. Fluorescence in situ hybridization analysis showed that more than 10 copies of the gene were recognized in all 5 cancers with 3+ staining and in 2 of the 4 tumors with 2+ staining. CONCLUSIONS Although a high level of overexpression of epidermal growth factor receptor is uncommon in gastric carcinomas, it almost exclusively occurs by gene amplification.

Detection of c-erbB-2 (HER-2/neu) amplification in breast carcinoma by fluorescence in situ hybridization on tissue sections and imprinted cells.

Abnormalities in c‐erbB‐2 have attracted a great deal of attention. Treatment using an antibody against the c‐erbB‐2 gene product is effective against breast cancers with amplification and/or overexpression of c‐erbB‐2. There is an urgent need to establish methodology for selecting patients who would benefit from this therapy. A total of 235 breast carcinomas were examined for c‐erbB‐2 protein overexpression by immunohistochemistry. Tissue sections with discernible immunostaining from 52 tumors, 70 negative tumors and smear imprints from 35 patients were examined by dual‐color fluorescence in situ hybridization (FISH) using probes specific for c‐erbB‐2 and the centromeric region of chromosome 17. The concordance between gene amplification and protein overexpression was 95.7%. When the findings of the two FISH preparation techniques were compared, no discrepancies were found in 24 of the tumors. However, differences were seen in eight cases. In six of these cases the differences did not affect the presence or absence of amplification, but in the other two cases, considered to show low‐level amplification on paraffin sections, polysomy 17 was detected instead. It was concluded that FISH is an excellent tool to detect gene amplification in particular, and FISH on touch imprints is a useful adjunct to differentiate between low‐level amplification and polysomy 17.

A case of male noninvasive intracystic papillary carcinoma forming a tumor in the nipple duct.

Epithelial tumors forming a mass in the male nipple are very rare. Paget’s disease, adenoma of the nipple (AON), and breast cancer must be considered for differential diagnosis. This report presents a 72-year-old man with spontaneous serous nipple discharge and an enlarged nipple measuring 2 cm in diameter. Ultrasonography provided no useful information regarding the nipple lesion. Nipple discharge cytology was negative and without any inflammatory cells. Since it is extremely uncommon for Paget’s disease and breast cancer to cause tumor in the nipple, AON was suggested. However, histopathological examination of the nipple resection revealed noninvasive intracystic papillary carcinoma of the nipple. Biopsy of the nipple is often necessary to diagnose this disease. Moreover, excisional biopsy of the tumor is recommended when possible, since it can accomplish both diagnosis and treatment in cases of AON or noninvasive intracystic papillary carcinoma.

A case of sclerosing lymphocytic lobulitis of the breast associated with diabetes mellitus

AbstractBackground: The benign breast disease sclerosing lymphocytic lobulitis is thought to result from autoimmune diseases causing insulin-dependent diabetes mellitus (IDDM) due to insulinitis. In cases of sclerosing lymphocytic lobulitis accompanied by IDDM, the clinical term “diabetic fibrous breast disease” has been proposed. Methods: A case of sclerosing lymphocytic lobulitis of the breast is described. Results: The patient was a 43-year-old woman diagnosed with non insulin-dependent diabetes mellitus (NIDDM) 8 years previously. Insulin therapy was thought to be necessary because treatment with glibenclamide was not effective. She visited our facility complaining of a lump in her right breast that was 5 cm in diameter, painless, rock-hard, discrete, and irregularly outlined. Biopsy was performed because breast cancer was strongly suggested by its hardness and its irregular internal echo on ultrasonography. Histopathological findings demonstrated marked stromal sclerosis and lymphocyte infiltration in the perivascular and perilobular areas. Sclerosing lymphocytic lobulitis was diagnosed. Conclusions: Referring physicians should avoid performing unnecessary repeated biopsies by recognizing this disease entity, which often occurs bilaterally.

A Case of Primary Intrahepatic Pure Cholesterol Stone Accompanied with Black Stone in the Gallbladder.

症例は50歳男性で, 右季肋部痛を主訴とし, 腹部超音波検査にて胆嚢, 肝内結石症を指摘された. ERCPでは肝外側区域胆管に狭窄を伴わない限局性の紡錐状拡張を認めた.胆摘, 肝外側区域切除術を施行した.摘出標本で, 胆嚢内には黒色で割面が無構造な小結石を認めた.肝臓には萎縮はなく, 拡張胆管内に黒色泥状の結石が充満し, 組織学的には軽度の胆管壁の肥厚を認めるのみで, 慢性増殖性胆管炎の像を認めなかった.結石分析の結果では胆嚢結石は炭酸カルシウム, ビリルビンカルシウム, リン酸カルシウムを含有し黒色石と診断した.肝内結石はコレステロールのみを含有しており純コレステロール結石と診断した.両結石形成の機序およびその関連性については不明であるが, われわれの文献検索の範囲内ではこのような症例は見られず, きわめてまれな1例と考えられる.