Ductal adenoma of the breast: immunohistochemistry of two cases

How predominant cell and stroma types harmonize to predict head and neck adenoid cystic carcinoma outcomes?

Adenoid cystic carcinoma (ACC) is an uncommon tumor that usually appears in the major salivary glands of the head and neck region, including the minor glands in the oral cavity, sinonasal tract, and other sites. ACC of the head and neck may have a low-grade histological appearance. This malignant tumor has unusual clinical characteristics such as occasional regional lymph node metastases and a prolonged yet continuously advancing clinical course. Additionally, it is an invasive tumor with perineural invasion, difficult-to-clear margins, metastasis, and localized recurrence. The cribriform and tubular proliferation of basaloid cells, which mostly display a myoepithelial cellular phenotype, are ACC's distinct histologic characteristics. The degree of genetic alterations and aneuploidy observed in tumor genomes are linked to the severity of histologic grade, which correlates with clinical prognosis. The three predominant cell types (PCTs) i.e., conventional ACC (C-ACC), myoepithelial-predominant ACC (M-ACC), and epithelial-predominant ACC (E-ACC)-and their respective applications will be reviewed. The function of extracellular matrix (ECM) components such as laminin, type IV collagen, fibronectin, and tenascin are also emphasized. An attempt has been made to explore the recent molecular diversity, regulatory pathways prevalent in PCT, ECM with its genetic changes, and translational utility with targeted therapies for ACC.

MUC1 (CD227): a multi-tasked molecule

Mucin 1 (MUC1 [CD227]) is a high-molecular weight (>400 kDa), type I membrane-tethered glycoprotein that is expressed on epithelial cells and extends far above the glycocalyx. MUC1 is overexpressed and aberrantly glycosylated in adenocarcinomas and in hematological malignancies. As a result, MUC1 has been a target for tumor immunotherapeutic studies in mice and in humans. MUC1 has been shown to have anti-adhesive and immunosuppressive properties, protects against infections, and is involved in the oncogenic process as well as in cell signaling. In addition, MUC1 plays a key role in the reproductive tract, in the immune system (affecting dendritic cells, monocytes, T cells, and B cells), and in chronic inflammatory diseases. Evidence for all of these roles for MUC1 is discussed herein and demonstrates that MUC1 is truly a multitasked molecule.

Histopathological study using computer database of 10 000 consecutive gastric specimens: (1) benign conditions

Using a computer database, the author investigated the histopathology of 10 000 consecutive gastric specimens, taken in the last 12 years (2002–2013) at the pathology laboratory of a Japanese hospital. Re-observation of the already examined histological sections was done when the histological diagnosis and findings on the computer data base were not very obvious. The gastric specimens were identified as 8579 benign conditions and 1421 malignant lesions. The 8579 benign conditions were comprised almost normal stomach in 74 cases (0.9%), chronic gastritis in 4374 (51.0%), benign gastric peptic ulcer in 2195 (25.6%), foveolar hyperplastic polyp in 1004 (11.7%), fundic gland polyp in 421 (4.9%), adenoma in 487 (5.6%), heterotopic pancreas in 9 (0.1%), pancreatic acinar metaplasia (PAM) in 8 (0.1%), and amyloidosis in 7 (0.1%). Chronic gastritis showed lymphocytic infiltration and frequently showed erosions and intestinal metaplasia. Gastric peptic ulcer showed exudate, necrosis, active inflammation, and regenerative atypia of the epithelium. Foveolar hyperplastic polyp revealed 23 malignant changes and frequently showed dysplastic glands and intestinal metaplasia. Fundic gland polyp demonstrated cystic dilations of fundic gland ducts. Gastric adenoma showed adenomatous proliferation in the superficial mucosa and cystic dilation of the epithelium under the adenoma. Heterotopic pancreas was located in the submucosa and consisted of acinar cells, ducts, and occasionally islets. PAM was a tiny lesion in the mucosa and consisted of only pancreatic acinar cells. Amyloidosis was primary amyloidosis with positive reaction with Congo-red stain.

Histopathological study using computer database of 10 000 consecutive gastric specimens: (2) malignant lesions

Using a computer database, the author investigated the histopathology of 10 000 consecutive gastric specimens collected in the last 12 years 2002–2013 at his pathology laboratory in a relatively large hospital in Japan. Examination of histological sections was done when appropriate. The gastric specimens were made up of 8579 benign conditions and 1421 malignant lesions. The latter comprised gastric carcinoma in 1342 cases (94.4%), gastrointestinal stromal tumor (GIST) in 34 (2.4%), mucosal-associated lymphoid tissue (MALT) lymphoma in 25 (1.8%), non-Hodgkin's malignant lymphoma in 19 (1.3%), and metastatic carcinoma in 1 case (0.1%). Of the 1342 cases of gastric carcinoma, the histological type was as follows: tubular adenocarcinoma in 755 cases, papillary adenocarcinoma in 176, mucinous adenocarcinoma in 147, signet ring cell carcinoma in 145, poorly differentiated adenocarcinoma in 114, adenosquamous carcinoma in 4, and metastatic small cell carcinoma from the lung in 1. In surgically resected cases, the number of early gastric carcinomas was 258 and of advanced carcinoma, 521 cases. In GIST (n = 34), there were 2 cases of the epithelioid type and 32 of the spindle cell type. The size of GIST ranged from 1–15 cm, with a mean of 5.6 cm. KIT (CD117) was positive in 34/34 cases, CD34 in 31/34, desmin 2/34, and S100 4/34. A genetic analysis was performed in 6 cases of GIST, all of which showed point mutation of KIT and/or PDGFRA genes. In MALT lymphoma (n = 25), centrocyte-like cells and lymphoepithelial lesions were seen in every case. Helicobactor pylori infection was noted in 92%. In non-Hodgkin's lymphoma (n = 19), 17 cases were of diffuse large B-cell lymphoma, and 1 was peripheral T-cell lymphoma, while 1 was NK-cell lymphoma.

Decidualization of uterine adenomyoma in a pregnant woman: a case report with immunohistochemical study

BACKGROUND

Decidualization of uterine adenomyoma has not been reported, to the best of the author's knowledge.

AIM

To report a case of uterine adenomyoma with decidualization.

CASE REPORT

A 43-year-old pregnant woman with "myoma" underwent cesarean operation and "myomectomy" at 37 gestation weeks. The operation was successful, and the baby and mother were healthy. Grossly, the "myoma" measured 12 × 10 × 10 cm, and the consistency was firm. Microscopically, the tumor was adenomyoma consisting of smooth muscle bundles and endometrial islands. Characteristically, the endometrial stroma showed marked decidualization. An immunohistochemical study showed that the decidual cells were positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, cytokeratin (CK)7, CK18, vimentin, CA125, CD10, estrogen receptor (ER), progesterone receptor (PgR), and Ki-67 (labeling 1 %). They were negative for CK34βE12, CK5/6, CK8, CK14, CK19, CK20, EMA, p63, desmin, α-smooth muscle actin, S100 protein, CK34, CD68, and p53. These results show that marked decidualization occurs in adenomyoma during pregnancy, and that the decidual cells are positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, CK7, CK18, vimentin, CA125, CD10, ER, and PgR.

CONCLUSION

A rare case of uterine adenomyoma with decidualization is reported.

CD5-positive marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the lung

CD5-positive marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the lung is very rare. An 82-year-old Japanese woman was found to have an abnormal lung shadow on chest X-ray photography, and was admitted to our hospital. Imaging modalities including X-ray photography, computed tomography, and magnetic resonance imaging showed a small (2 × 1 × 1 cm) opacity of the right upper lobe. Transbronchial lung biopsy was performed. It showed severe proliferation of small lymphocytes. The small lymphocytes were centrocytes-like, and minor plasma cell differentiation was recognized. Lymphoepithelial lesions were scattered. Immunohistochemically, the tumor cells were positive for CD5, CD20, CD43, CD45, CD79α, bcl-2, and κ-chain, but negative for CD2, CD3, CD10, CD21, CD23, CD35, CD45RO, CD56, IgA, IgG, IgM, IgD, λ-chain, TdT, and cyclin D1. The Ki-67 labeling was 10%. CD3-positive and CD45RO-positive inflammatory T-cells were scattered in small amount. The pathological diagnosis was CD5-positive marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the lung. The patient was treated with chemotherapy (CHOP: cyclophosphamide, hydroxydaunorbicin, vincristine, and predonisone), and the lung tumor disappeared. The patient is now free of the lymphoma 10 years after the first manifestation.

Mucins in the pathogenesis of breast cancer: implications in diagnosis, prognosis and therapy

Mucins are high molecular weight, multifunctional glycoproteins comprised of two structural classes-the large transmembrane mucins and the gel-forming or secreted mucins. The primary function of mucins is to protect and lubricate the luminal surfaces of epithelium-lined ducts in the human body. Recent studies have identified a differential expression of both membrane bound (MUC1, MUC4 and MUC16) and secreted mucins (MUC2, MUC5AC, MUC5B and MUC6) in breast cancer tissues when compared with the non-neoplastic breast tissues. Functional studies have also uncovered many unique roles of mucins during the progression of breast cancer, which include modulation in proliferative, invasive and metastatic potential of tumor cells. Mucins function through many unique domains that can form complex association with various signaling molecules including growth factor receptors and intercellular adhesion molecules. While there is growing information about mucins in various malignancies including breast cancer, no focused review is there on the expression and functional roles of mucins in breast cancer. In this present review, we have discussed the differential expression and functional roles of mucins in breast cancer. The potential of mucins as diagnostic and prognostic markers and as therapeutic targets in breast cancer have also been discussed.

Malignant myoepithelioma of the breast

Malignant myoepithelioma of the breast is rare. A 50-year-old Japanese woman was admitted to our hospital because of a right breast tumor (11 × 10 × 5.5 cm). Core needle biopsy revealed malignant spindle cells. A mastectomy was performed. The tumor consisted of malignant spindle, round, pleomorphic and giant cells with many mitotic figures and necrotic areas. Tumor and osteoclast-like giant cells were scattered. Much lymphovascular permeation was seen. In a few areas, particularly on the tumor periphery, there were merges between the tumor cells and myoepithelial cells of the non-tumorous ducts, as if the tumor emanated from the duct myoepithelium. The tumor was invasive into the skin and pectoral muscle. Immunohistochemically, the tumor cells were diffusely positive for vimentin, CD10, α-smooth muscle antigen, and Ki-67 (labeling = 95%). The significant areas of the tumor were positive for S100 protein, p63, p53, CD68, caldesmon, desmin and TGFβ1. A few areas were positive for pancytokeratin (AE1/3), cytokeratin (CK) 5/6, and CK 34βE12. In contrast, the tumor cells were negative for pancytokeratins (WSS, CAM5.2), CK7, CK8, CK14, CK18, CK19, CK20, EMA, CEA, bcl-2, myoglobin, CD34, CD56, CD45, HMB45, GFAP, α-1-antitrypsin, synaptophysin, estrogen receptor, progesterone receptor, HER2/neu, MUC1, MUC2, MUC5AC and MUC6. The author diagnosed the tumor as malignant myoepithelioma, as myoepithelial markers (C10, p63, S100 protein, α-smooth muscle actin, caldesmon) were positive, and also because there was a transition between the tumor cells and myoepithelium of non-tumorous ducts. The grade of the tumor was high. The patient was treated with chemoradiation and was free of disease 5 months after the operation.

Spontaneously immortalised bovine mammary epithelial cells exhibit a distinct gene expression pattern from the breast cancer cells

BACKGROUND

Spontaneous immortalisation of cultured mammary epithelial cells (MECs) is an extremely rare event, and the molecular mechanism behind spontaneous immortalisation of MECs is unclear. Here, we report the establishment of a spontaneously immortalised bovine mammary epithelial cell line (BME65Cs) and the changes in gene expression associated with BME65Cs cells.

RESULTS

BME65Cs cells maintain the general characteristics of normal mammary epithelial cells in morphology, karyotype and immunohistochemistry, and are accompanied by the activation of endogenous bTERT (bovine Telomerase Reverse Transcriptase) and stabilisation of the telomere. Currently, BME65Cs cells have been passed for more than 220 generations, and these cells exhibit non-malignant transformation. The expression of multiple genes was investigated in BME65Cs cells, senescent BMECs (bovine MECs) cells, early passage BMECs cells and MCF-7 cells (a human breast cancer cell line). In comparison with early passage BMECs cells, the expression of senescence-relevant apoptosis-related gene were significantly changed in BME65Cs cells. P16INK4a was downregulated, p53 was low expressed and Bax/Bcl-2 ratio was reversed. Moreover, a slight upregulation of the oncogene c-Myc, along with an undetectable level of breast tumor-related gene Bag-1 and TRPS-1, was observed in BME65Cs cells while these genes are all highly expressed in MCF-7. In addition, DNMT1 is upregulated in BME65Cs. These results suggest that the inhibition of both senescence and mitochondrial apoptosis signalling pathways contribute to the immortality of BME65Cs cells. The expression of p53 and p16INK4a in BME65Cs was altered in the pattern of down-regulation but not "loss", suggesting that this spontaneous immortalization is possibly initiated by other mechanism rather than gene mutation of p53 or p16INK4a.

CONCLUSIONS

Spontaneously immortalised BME65Cs cells maintain many characteristics of normal BMEC cells and exhibit non-malignant transformation. Although this cell line displays altered patterns of gene expression, it is clearly distinct from malignant breast cancer cell line. It showed that co-inhibition of cellular senescence and mitochondrial apoptosis pathways coordinates BME65Cs cells immortalisation. Additionally, mechanisms other than gene mutation are likely to be involved in regulation of cellular functions. This study provides an insight into the relationship between cell senescence and immortalisation. BME65Cs cells will be useful in future studies of cellular senescence and tumorigenesis.

Amelanotic malignant melanoma of the esophagus: Report of two cases with immunohistochemical and molecular genetic study of KIT and PDGFRA

The author reports herein two cases of amelanotic malignant melanoma of the esophagus. Case 1 is an 87-year-old woman who was admitted to our hospital because of nausea and vomiting. Endoscopic examination revealed an ulcerated tumor of the distal esophagus, and a biopsy was taken. The biopsy showed malignant polygonal and spindle cells. No melanin pigment was recognized. Immunohistochemically, the tumor cells were positive for melanosome (HMB45), S100 protein, KIT and Platelet derived growth factor receptor-α (PDGFRA). The patient was treated by chemotherapy and radiation, but died of systemic metastasis 12 mo after the presentation. Case 2 is a 56-year-old man presenting with dysphagia. Endoscopic examination revealed a polypoid tumor in the middle esophagus, and a biopsy was obtained. The biopsy showed malignant spindle cells without melanin pigment. Immunohistochemically, the tumor cells were positively labeled for melanosome, S100 protein, KIT and PDGFRA. The patient refused operation, and was treated by palliative chemotherapy and radiation. He died of metastasis 7 mo after the admission. In both cases, molecular genetic analyses of KIT gene (exons 9, 11, 13 and 17) and PDGFRA gene (exons 12 and 18) were performed by the PCR direct sequencing method, which showed no mutations of KIT and PDGFRA genes. This is the first report of esophageal malignant melanoma with an examination of the expression of KIT and PDGFRA and the mutational status of KIT and PDGFRA genes.