Late onset Epstein-Barr virus-associated lymphoproliferative disease after allogeneic bone marrow transplant presenting as breast masses

Is Human Papilloma Virus Associated with Breast Cancer? A Review of the Molecular Evidence

BACKGROUND

Although the association of human papillomavirus (HPV) with many cancers is well established, the involvement of HPV in breast cancer remains controversial. The purpose of this study is to perform a comprehensive review of the results and methods used to demonstrate that HPV markers are present in human breast cancer, and how well these studies fulfil the criteria for proving the viral etiology of a cancer.

STUDY DESIGN

We conducted a search for molecular studies published until November 2016 that relate human breast cancer to HPV.

RESULTS

Forty-three original molecular studies were found, some of which compared cases to nonneoplastic controls. Some investigations did not identify HPV in mammary tissue, but others identified it with different frequencies of positivity, varying between 1.2 and 86%. In most case-control studies (21/24 studies), positivity in cases was found to be higher than in controls, but odds ratios and confidence intervals were not reported.

CONCLUSION

The results are controversial. However, they arouse a great interest in the potential participation of HPV in breast carcinogenesis, but rather as an essential cause-effect participant, at least as a co-participant in some cases. The circumstance of HPV positivity in breast cancer can be criticized, but the elements that clearly demonstrate it in a number of cases are also relevant.

Isolated post-transplantation lymphoproliferative disease involving the breast and axilla as peripheral T-cell lymphoma

Post-transplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of diseases that represent serious complications following immunosuppressive therapy for solid organ or hematopoietic-cell recipients. In contrast to B-cell PTLD, T-cell PTLD is less frequent and is not usually associated with Epstein Barr Virus infection. Moreover, to our knowledge, isolated T-cell PTLD involving the breast is extremely rare and this condition has never been reported previously in the literature. Herein, we report a rare case of isolated T-cell PTLD of the breast that occurred after a patient had been treated for allogeneic peripheral blood stem cell transplantation due to acute myeloblastic leukemia.

Epstein-Barr virus and breast cancer: epidemiological and molecular study on Egyptian and Iraqi women

BACKGROUND AND PURPOSE

The role of Epstein-Barr virus (EBV) in breast carcinogenesis is still controversial. Unraveling this relationship is potentially important for better understanding of breast cancer etiology, early detection and possibly prevention of breast cancer. The aim of the current study is to unravel the association between EBV and primary invasive breast cancer (PIBC) in two different Arab populations (Egyptian and Iraqi women).

PATIENTS AND METHODS

The study was done on paraffin-embedded tissues of 40 Egyptian and 50 Iraqi patients with PIBC in addition to 20 normal breast tissues as controls for each group. Both controls and neoplastic tissues were assessed for the expression of EBV genes and proteins (EBNA-1, LMP-1, and EBER) as well as CD21 marker by immunohistochemistry (IHC), in situ hybridization (ISH) and PCR techniques.

RESULTS

Our gold standard for EBV reactivity in breast cancer cases was positivity of both EBNA1 by PCR and EBER by in situ hybridization. EBV was detected in 18/40 (45%) and 14/50 (28%) of Egyptian and Iraqi women; respectively where p=0.073, compared to 0/20 (0%) of their control groups (p<0.05). Regarding the association between EBV positivity and tumor grade, there was not any statistical significant difference between EBV presence and tumor grade in both populations where p=0.860 and p=0.976 and the calculated rank biserial correlation coefficient was 0.114 and 0.269 for Egyptian and Iraqi women respectively.

CONCLUSION

Our findings show that EBV might act as a promoter for the development of PIBC and it might contribute to increased tumor aggressiveness in Egyptian and Iraqi patients.

Are viruses associated with human breast cancer? Scrutinizing the molecular evidence

The three viruses most studied as possible causes of human breast cancer are mouse mammary tumor virus-like sequences (MMTV-LS), Epstein-Barr virus (EBV), and oncogenic (high risk) types of human papilloma virus (HPV). The first step in fulfilling traditional criteria for inferring that a cancer is caused by a virus is to demonstrate the virus in the affected tissue. Molecular techniques, compared to host antibody assessment and immunohistochemistry, are the most definitive in establishing viral presence. Results of 85 original molecular research investigations to detect one or more of the three viruses have been extremely divergent with no consensus reached. We evaluated the methodology of these studies for the following: type of molecular assay, DNA/RNA quality control, positive and negative assay controls, type of fixation, genome targets, methods for preventing and detecting molecular contamination, pathology of specimens processed, sample size, and proportion of specimens positive for the viral genome region targeted. Only seven of the studies convincingly demonstrated the presence of an oncogenic virus biomarker (EBV: 4/30 studies (13%); HPV 3/29 studies (10%), whereas 25 convincingly demonstrated absence of the virus studied (MMTV-LS: 4/25 (16%); EBV: 15/30 (50%); 6/29 (21%). The remainder of the studies suffered shortcomings, which, in our opinion, prevented a definitive conclusion. Only one of the studies compared frequency of the virus in breast tissue of breast cancer patients versus appropriate normal control subjects with no history of breast cancer. None of the studies were designed as epidemiologic studies to determine if the presence of the virus was significantly associated with breast cancer. Based on our evaluation, the data in the publications reviewed here remain preliminary, and do not justify a conclusion that MMTV-LS, HPV, or EBV are causally associated with breast cancer. However, they form a valuable basis for redirecting future studies.

Association between Epstein-Barr virus infection and risk for development of pregnancy-associated breast cancer: joint effect with vitamin D?

BACKGROUND

Few studies have evaluated the role of the ubiquitous Epstein-Barr virus (EBV) infection, together with levels of the immunomodulator, vitamin D, in different breast cancer entities. We studied, prospectively, the association of EBV and vitamin D status with the risk of pregnancy-associated breast cancer (PABC), breast cancer diagnosed during pregnancy or 1 year post-partum, using a nested case-control study.

METHODS

Serum vitamin D and antibodies to EBV were measured for 108 PABC cases of the Finnish Maternity Cohort, and 208 controls matched for date of birth, date of sampling and parity. The joint effect of vitamin D and EBV on the risk of PABC was evaluated.

RESULTS

EBV seropositivity was generally not associated with the risk of PABC. Among individuals with sufficient (≥75 nmol/l) levels of vitamin D, we, however, found similar increased risk estimates for PABC associated with serum immunoglobulin G (IgG) antibodies to EBV early antigens [odds ratio (OR)=7.7, 95% (confidence interval) CI 1.4-42.3] and the viral reactivator protein, ZEBRA (OR=7.8, 95% CI 1.1-61.2).

CONCLUSION

Immunological markers of EBV reactivation status among individuals with sufficient vitamin D levels were consistently associated with increased risk of the disease. This suggests that EBV reactivation may be an indicator of the progression of breast cancer occurring soon after pregnancy, while the virus probably is not the aetiological agent.

A clinical review of breast involvement in acute leukemia

The breast continues to be reported as a site of resistant leukemia despite current curative protocols. To characterize disease behavior and potential for lengthy survival after breast relapse, a study was undertaken of 153 cases reported between 1969 and 2005. Authors were contacted for follow-up. There were 105 AML and 48 ALL cases identified. Ninety percent of female patients were younger than 50 and leukemia was temporally related to pregnancy in 13. Eight cases were males. Remissions were typically of short duration, principally due to further extramedullary relapses, in 3 main sites in both AML and ALL: contralateral breast, gynecologic organs, and CNS. However, there are cases of disease-free survival up to 26+ years after intensive treatment. Leukemia growing in the breast may follow a distinctive pattern, and prompt initiation of intensive multi-cycle treatment, assuming occult site involvement, with consideration of CSF prophylaxis, should increase the potential for disease eradication.

Epstein-Barr Virus and Breast Cancer: State of the Evidence for Viral Carcinogenesis

As the etiology and progression of breast cancer remain incompletely understood, novel routes of disease pathogenesis are important to consider. Viral pathogens have not been much explored, but recent interest has focused on Epstein-Barr virus (EBV). Studies of an association of this ubiquitous herpesvirus with breast cancer have had notably inconsistent results, marked by varying EBV presence (from 0% to 50% of tumors) and the absence of certain viral characteristics found in other EBV-related malignancies. The research has been plagued by the technical challenges of localizing EBV to tumor cells and by a tendency to overlook epidemiological cofactors, shown in all other EBV-related cancers to impact the EBV association. Breast cancer studies to date have used several viral detection methods of varying or uncertain sensitivity and specificity; most have involved small and/or poorly characterized case series and paid insufficient attention to epidemiological cofactors relevant to breast cancer and to EBV-related malignancies. Given these limitations and the established complexity of the connection of EBV with other cancers, a definitive judgment regarding the presence of this virus in breast cancer cannot yet be rendered. Recent advances in laboratory methodologies should help overcome the challenges of EBV detection in breast cancers. Further research is warranted, given the potential for an EBV association to inform not only breast cancer etiology but also early detection, treatment, and prevention.

A Viral Aetiology for Breast Cancer: Time to Re-Examine the Postulate

Despite decades of research, no aetiologic factor(s) for human breast cancer has been identified and the search for a causal agent has all but been abandoned during the past thirty years. Over 60 years ago, it was demonstrated that breast tumours in mice are caused by an oncornavirus, murine mammary tumour virus (MMTV). Whilst many at that time postulated a similar virus might be the causative agent of human breast cancer, genetic evidence was difficult to obtain primarily because of the occurrence of endogenous human retrovirus (HER) sequences within the human genome that share extensive regions of nucleotide homology with MMTV. Recently, there has been a resurgence of interest in the possibility that a significant proportion of human breast cancers may be caused by viral infections. Two candidate viruses have been proposed, a human retroviral analogue of MMTV (which differs significantly in sequence and characteristics from HERs) and, the Epstein-Barr virus (gamma-herpes virus). These two viruses have been reported to occur in up to 37 and 50% of breast cancer cases, respectively. Here we present the background to the infectious hypothesis for the aetiology of breast cancer and review recent findings.

Posttransplant lymphoproliferative disorders presenting at sites of previous surgical intervention

Early diagnosis of posttransplant lymphoproliferative disorder (PTLD) requires a high level of clinical suspicion. PTLD occurs mainly in the lymphoid tissue, allograft organ, bowel, and central nervous system. The diagnosis may not be considered initially when disease is localized to other sites. Retrospective review of the PTLD series at the University of Pittsburgh Medical Center showed that 4 of 418 patients (1%) presented with signs and symptoms localized to sites of previous surgical intervention (choledochojejunostomy site, ileosigmoid anastomotic site, site of saphenous vein stripping, and intrabiliary site of percutaneous transhepatic catheter). All patients showed symptomatic, Epstein-Barr virus-positive B-cell PTLD of varying histology. Three of four patients ultimately died with tumor, and the fourth died of unrelated causes. PTLD should be included in the differential diagnosis when clinical signs and symptoms localize to anastomotic sites, surgical incision sites, or sites of longstanding catheter placement in immunosuppressed organ transplant recipients.

Epstein-Barr virus-associated B cell lymphoproliferative disorder following mismatched related T cell-depleted bone marrow transplantation

Epstein-Barr virus (EBV) is closely associated with the progressive and often fatal lymphoproliferative disorders (LPD) in post bone marrow transplantation (BMT) and immunocompromised hosts. The incidence increases significantly when alternative donors or manipulation of marrow graft are used. A total of 318 consecutive BMT from partially mismatched related family donors (PMRD) were performed between February 1993 and June 1998. Known risk factors for the development of EBV-LPD were analyzed which included HLA mismatches, T cell depletion, antithymocyte globulin (ATG), and graft-versus-host disease (GVHD). Eighteen patients (5.7%) developed EBV-LPD at a median of 137 days post BMT (range 48-617). The estimated probability of developing EBV-LPD was 0.13 (95% CI 0.07-0.19) at 5 years. The incidence of grade II to IV GVHD was 19.2%, which translated into an increased trend of EBV-LPD. No correlation with other risk factors was observed. Treatment consisted of supportive antiviral agents, tapering of immunosuppressive regimens, donor leukocyte infusions and radiation. Three patients are alive and disease-free at a median follow-up of 69 months (range 36-71). We observed a lower than expected incidence of EBV-LPD despite existing multiple high-risk factors. We believe prevention and early control of GVHD may contribute to this finding.

No significant association of Epstein-Barr virus infection with invasive breast carcinoma

We studied 48 cases of invasive breast carcinoma for evidence of Epstein-Barr virus (EBV), which is associated with many human malignancies. In situ hybridization studies to detect the presence of EBV-encoded small nonpolyadenylated RNA (EBER)-1 were performed in paraffin sections. Immunohistochemical studies to detect EBV nuclear antigen (EBNA)-1, latent membrane protein (LMP)-1, and the transactivating immediate-early BZLF1 (ZEBRA) protein were also performed in paraffin sections. The presence of EBV genomic DNA was studied by polymerase chain reaction (PCR) amplification using sets of primers flanking the EBNA-4 and the EBV-LMP-1 genes in frozen tissues. Southern blot analysis using a probe flanking the EBV terminal repeat region was then attempted in cases that were PCR-positive. Five of 48 cases (10%) of breast carcinoma showed focal EBER-positive tumor cells. Twelve cases (25%) were positive for EBNA-1 by immunohistochemistry, all but one different from the EBER-positive cases. None of the cases were positive for LMP-1 or ZEBRA protein by immunohistochemistry. PCR studies for EBNA-4 and LMP-1 were each positive in five cases (including three cases in common). However, Southern blot studies successfully performed in all but one of the PCR-positive cases were completely negative. The identification of EBV by any methodology was not correlated with tumor size, grade, or lymph node status. This study demonstrated evidence of EBV infection in tissues involved by invasive breast carcinomas in a significant subset of cases. However, the lack of localization of EBV infection to a significant population of the tumor cells in any case, the negativity by Southern blot hybridization, and the lack of expression of multiple antigens in any case strongly argue against a significant role for EBV in the pathogenesis of breast carcinoma.

Detection of Epstein-Barr virus in invasive breast cancers

BACKGROUND

Epstein-Barr virus (EBV) may be a cofactor in the development of different malignancies, including several types of carcinomas. In this study, we investigated the presence of EBV in human breast cancers.

METHODS

We used tissues from 100 consecutive primary invasive breast carcinomas, as well as 30 healthy tissues adjacent to a subset of the tumors. DNA was amplified by use of the polymerase chain reaction (PCR), with the primers covering three different regions of the EBV genome. Southern blot analysis was performed by use of a labeled EBV BamHI W restriction fragment as the probe. Infected cells were identified by means of immunohistochemical staining, using monoclonal antibodies directed against the EBV nuclear protein EBNA-1.

RESULTS

We were able to detect the EBV genome by PCR in 51% of the tumors, whereas, in 90% of the cases studied, the virus was not detected in healthy tissue adjacent to the tumor (P<.001). The presence of the EBV genome in breast tumors was confirmed by Southern blot analysis. The observed EBNA-1 expression was restricted to a fraction (5%-30%) of tumor epithelial cells. Moreover, no immunohistochemical staining was observed in tumors that were negative for EBV by PCR. EBV was detected more frequently in breast tumors that were hormone-receptor negative (P =.01) and those of high histologic grade (P =.03). EBV detection in primary tumors varied by nodal status (P =.01), largely because of the difference between subjects with more than three lymph nodes versus less than or equal to three lymph nodes involved (72% versus 44%).

CONCLUSIONS

Our results demonstrated the presence of the EBV genome in a large subset of breast cancers. The virus was restricted to tumor cells and was more frequently associated with the most aggressive tumors. EBV may be a cofactor in the development of some breast cancers.