Occult primary breast carcinoma presented as an axillary mass: A Diagnostic Challenge.

INTRODUCTION: Occult primary breast carcinoma (OBC) manifesting as axillary nodal metastasis without an identifiable breast primary is exceptionally rare. It continues to pose a diagnostic challenge to pathologists. Here, we report a case of OBC with emphasis on the usefulness of immunohistochemistry to determine the primary site of tumour. CASE REPORT: A 58-year-old female presented with a 3-cm painless right axillary mass. Extensive radiological investigations that include mammography, ultrasonography of the breasts and positron emission tomography (PET) scan failed to conclude the primary site of the tumour. Histological examination of the lymph node revealed loosely cohesive sheets of poorly differentiated malignant cells, without discernible glandular or squamous differentiation. Immunohistochemically, the malignant cells exhibited diffuse immunoreactivity toward pan-cytokeratin and CK7, while leukocyte common antigen, S100 and CK20 were negative. A second panel of immunomarkers was carried out. The malignant cells expressed breast-specific markers (GATA-3, GCDFP-15 and mammaglobin), and were negative for ER, PR and TTF-1 immunohistochemistry. A diagnosis of OBC was rendered. DISCUSSION: Breast primary must always be considered in the differential diagnosis in patients with sole presentation of axillary lymphadenopathy. The breast-specific immunomarkers play a pivotal role in the diagnosis of ER, PR-negative occult breast cancer.

Anaplastic lymphoma kinase (ALK) mutations in patients with adenocarcinoma of the lung.

BACKGROUND: Non-small cell lung cancer (NSCLC) is a major cause of cancer-related death. Approximately 2-16% of NSCLC patients with wild-type epidermal growth factor receptor (EGFR) harbour anaplastic lymphoma kinase (ALK) mutations. Both EGFR and ALK mutations occur most commonly in Asian patients with NSCLC. As targeted therapy is available for NSCLC patients with these mutations, it is important to establish reliable assays and testing strategies to identify those most likely to benefit from this therapy. MATERIALS AND METHODS: Patients diagnosed with adenocarcinoma of the lung between 2010 and 2014 were tested for EGFR mutations. Of these, 92 cases were identified as EGFR wild type and suitable candidates for ALK testing utilising immunohistochemistry and the rabbit monoclonal antibody D5F3. The reliability of the IHC was confirmed by validating the results against those achieved by fluorescence in situ hybridisation (FISH) to detect ALK gene rearrangements. RESULTS: Twelve (13%) cases were positive for ALK expression using immunohistochemistry. Of the 18 evaluable cases tested by FISH, there was 100% agreement with respect to ALK rearrangement/ALK expression between the assays, with 11 cases ALK negative and 7 cases ALK positive by both assays. ALK tumour expression was significantly more common in female compared to male patients (29.6% vs. 6.2%, P < 0.001), detected exclusively in patients that had never smoked (P < 0.001) and more frequently in metastases (22.7%) than in primary tumours (10%) (P = 0.047). CONCLUSIONS: Detection of ALK expression by IHC is reliable and the most practical way of identifying NSCLC patients likely to benefit from crizotinib treatment.

Identification of a novel protein encoded by the BamHI A region of the Epstein-Barr virus.

An unusual set of 3' coterminal, spliced mRNAs transcribed through the BamHI A fragment have been previously identified in nasopharyngeal carcinoma (NPC) tissues. These RNAs have also been detected at low levels in Burkitt's lymphoma (BL) cell lines and Epstein-Barr virus (EBV)-transformed lymphocytes. Sequence analyses of clones from a cDNA library derived from the C15 NPC tumor indicated that the primary transcripts are differentially spliced, giving rise to a family of related transcripts, all of which encompass the BARF0 open reading frame (ORF) at the 3' end of the transcripts. One cDNA was identified that extended the BARF0 ORF at the 5' end, forming the RK-BARF0 ORF. In this study, a rabbit antiserum to a synthetic peptide representing an amino acid sequence encoded by the BARF0 ORF was prepared. This antiserum detected a glutathione S-transferase-BARF0 fusion protein and both BARF0 and RK-BARF0 proteins expressed from transfected constructs in H1299 cells. The serum also immunoprecipitated the 20-kDa BARF0 and 30-kDa RK-BARF0 in vitro-translated proteins. Immunoblot analyses identified a protein doublet of 30 and 35 kDa in all of the EBV-infected cell lines tested. Cellular fractionation studies revealed that the proteins were membrane associated. The sizes of the proteins detected in cell lines and their association with membranes suggests that they are likely encoded by the RK-BARF0 transcript, which is predicted to contain a membrane localization signal. The proteins were also detected in protein extracts prepared from NPC biopsies and a BL biopsy but not from hairy leukoplakia, a permissive EBV infection. These results reveal that the rightward RNA transcripts from the BamHI A region of EBV encode one or more proteins that are expressed in latently infected cells and in tumor tissue.

Transfer factor with anti-EBV activity as an adjuvant therapy for nasopharyngeal carcinoma: a pilot study.

Overall survival of nasopharyngeal carcinoma (NPC) at UICC stage IV still remains unsatisfactory even with combination chemotherapy (CT) and radio-therapy (RT). In view of the association of reactivation of Epstein-Barr virus (EBV) with the development and recurrence of NPC, immunotherapy in the form of transfer factor (TF) with specific activity against EBV (TF-B1) was suggested as an adjuvant to a combination of CT and RT in order to improve survival. In the present study, 6 UICC stage IV patients received TF-B1 and another 6 patients matched for disease stage were given TF prepared from peripheral blood leucocytes (TF-PBL). Results were compared with another 18 patients matched by age, sex, and stage of disease who received standard therapy without TF during the same period (C group). After a median follow up of 47.5 months, the survival for the TF-B1 group was found to be significantly better (P = < 0.05) than the PBL and C group. While the 8 patients with distant metastasis (DM), not treated with TF-B1 (6 in the control and 2 in the PBL group), died due to progressive disease (average survival being 14.3 months), both patients with DM in the TF-B1 group had complete remission: one died of tuberculosis after surviving for 3.5 years and another is still alive, disease free, after 4.2 years. Although the series involved a small number of cases, the apparent effect of adjuvant immunotherapy in the form of TF with anti-EBV activity is of considerable interest.

Thyroid metastasis from nasopharyngeal carcinoma: a case report.

Anaplastic nasopharyngeal carcinoma (NPC) metastatic to the thyroid gland is rare. We report the first such case in a 54-year-old Malaysian Chinese woman. The correct diagnosis should be made so that thyroidectomy may be avoided and an appropriate chemoradiotherapeutic regimen instituted.

Epstein-Barr virus infection in carcinoma of the salivary gland.

Undifferentiated carcinoma of the parotid gland contains clonal Epstein-Barr virus episomes without ladder arrays of restriction enzyme fragments representing virion DNA. Analysis of Epstein-Barr virus transcription in situ in parotid carcinoma specimens revealed that the EBER RNAs, latent membrane protein mRNA, and the BamHI-A rightward reading frame, BARF0, are expressed in the malignant epithelial cells.

Expression of the Epstein-Barr virus BamHI A fragment in nasopharyngeal carcinoma: evidence for a viral protein expressed in vivo.

A family of mRNAs that are transcribed rightward through the BamHI A fragment have been detected in C15, a nasopharyngeal carcinoma (NPC) which has been passaged in nude mice. Northern (RNA) blot hybridizations indicate that these RNAs are also expressed in three other NPCs which have been established in nude mice and in an NPC obtained at biopsy. Moreover, hybridization in situ detected transcription from BamHI A in 12 NPCs and 1 Epstein-Barr virus (EBV)-containing carcinoma of the parotid gland. In each case, transcription was detected in all of the malignant epithelial cells. Transcription was not detected in two cases of EBV-positive lymphoma biopsies by in situ hybridization nor in latently infected EBV-positive lymphoblastoid cell lines by Northern blot hybridization. The consistent transcription of these sequences in latently infected epithelial malignancy but not in lymphoid cells suggests that this viral function is associated with latent EBV infection of epithelial cells. Sequence analysis of a cDNA synthesized from the C15 tumor, representing the 3' end of BamHI A messenger RNA, revealed an open reading frame (ORF). Translation of this ORF in vitro produced several peptides that were immunoprecipitated with antisera from patients with NPC. The detection of antibodies to the protein encoded by the ORF present in the BamHI A cDNA indicates that BamHI A encodes a protein which is expressed in vivo and is antigenic.

Epstein-Barr virus small nuclear RNAs are not expressed in permissively infected cells in AIDS-associated leukoplakia.

Epstein-Barr virus (EBV) DNA structure and gene expression were analyzed in tissue specimens from oral hairy leukoplakia (HLP), a mucocutaneous lesion that develops in patients infected with human immunodeficiency virus (HIV). The structure of the terminal restriction enzyme fragments of EBV revealed that HLP is a permissive infection without a predominant, detectable population of EBV episomal DNA. In RNA preparations from this uniquely permissive infection, EBV replicative mRNAs could be identified by Northern analysis; however, the virally encoded small nuclear RNAs, the EBERs, were not detected in most HLP RNA preparations. In situ hybridization detected EBER expression in very rare cells. These data indicate that unlike other viral small nuclear RNAs, the EBERs are not expressed during viral replication and must participate in the complex maintenance of latent EBV infection.

Novel transcription from the Epstein-Barr virus terminal EcoRI fragment, DIJhet, in a nasopharyngeal carcinoma.

Transcription of Epstein-Barr virus (EBV) genes in epithelial tissue, one of the two principal cell types infected by EBV, is not well characterized. EBV transcription in a nasopharyngeal carcinoma established in nude mice, C15, has been analyzed by using strand-specific RNA probes and sequence analysis of a C15 cDNA library. In C15, two equally abundant mRNAs of 3.7 and 2.8 kilobases (kb) are encoded by the sequences that encode latent membrane protein (LMP). Hybridization with probes specific for the 3' end of the LMP mRNA to Northern (RNA) blots and sequence analysis of cDNAs representing the messages indicated that the 3.7- and 2.8-kb mRNAs are 3' coterminal. Sequence analysis of additional cDNAs revealed an mRNA that is spliced identically to the LMP mRNA but is initiated 5' to the promoter for LMP. A probe representing the sequences contained within the cDNA which are 5' to the LMP promoter identified the 3.7-kb mRNA in C15 and a low-abundance 3.7-kb mRNA in B95-8 RNA. These data indicate that transcription of the LMP-encoding sequences is complex and that LMP can be expressed from an additional RNA in both nasopharyngeal carcinoma and lymphoid cells. Hybridization with BamHI-A identified a predominant 4.8-kb mRNA and two less abundant larger-molecular-weight mRNAs transcribed in C15. These mRNAs are consistently expressed in all passages in nude mice of the C15 tumor. Hybridization with strand-specific probes and sequence analysis of three cDNAs revealed that these mRNAs are transcribed from left to right. Sequence analysis of cDNAs representing the 3' end of the mRNAs identified an open reading frame that could potentially encode a protein of 174 amino acids. In situ hybridization of a 35S-labeled RNA probe homologous to the BamHI-A cDNA to tissue sections revealed that the BamHI-A mRNA is not focally expressed and is transcribed in all cells within the C15 tumor. Linear forms of EBV DNA were not detected in any of the C15 tumors, and replicative viral antigens have not been detected. These data suggest that the C15 tumor represents a latently infected tumor and that the transcription from BamHI-A, which is expressed in all cells, is not associated with virus replication.