The Role of Oncogenic Viruses in the Pathogenesis of Sporadic Breast Cancer: A Comprehensive Review of the Current Literature.

Breast cancer is the most common malignancy in the female sex; although recent therapies have significantly changed the natural history of this cancer, it remains a significant challenge. In the past decade, evidence has been put forward that some oncogenic viruses may play a role in the development of sporadic breast cancer; however, data are scattered and mostly reported as sparse case series or small case-control studies. In this review, we organize and report current evidence regarding the role of high-risk human papillomavirus, mouse mammary tumor virus, Epstein-Barr virus, cytomegalovirus, bovine leukemia virus, human polyomavirus 2, and Merkel cell polyomavirus in the pathogenesis of breast cancer.

Molecular characterization of diffuse large B-cell lymphomas associated with hepatitis C virus infection.

Hepatitis C virus (HCV)-associated diffuse large B-cell lymphoma (DLBCL) displays peculiar clinicopathological characteristics, but its molecular landscape is not fully elucidated. In this study, we investigated the clinicopathological and molecular features of 54 patients with HCV-associated DLBCL. The median age was 71 years. An underlying marginal zone lymphoma component was detected in 14.8% of cases. FISH analysis showed rearrangements involving BCL6 in 50.9% of cases, MYC in 11.3% and BCL2 in 3.7%. Lymph2Cx-based assay was successful in 38 cases, recognizing 16 cases (42.1%) as ABC and 16 cases as GCB subtypes, while six resulted unclassified. ABC cases exhibited a higher lymphoma-related mortality (LRM). Next-generation sequencing analysis showed mutations in 158/184 evaluated genes. The most frequently mutated genes were KMT2D (42.6%), SETD1B (33.3%), RERE (29.4%), FAS and PIM1 (27.8%) and TBL1XR1 (25.9%). A mutation in the NOTCH pathway was detected in 25.9% of cases and was associated with worst LRM. Cluster analysis by LymphGen classified 29/54 cases within definite groups, including BN2 in 14 (48.2%), ST2 in seven (24.2%) and MCD and EZB in four each (13.8%). Overall, these results indicate a preferential marginal zone origin for a consistent subgroup of HCV-associated DLBCL cases and suggest potential implications for molecularly targeted therapies.

Retrospective Investigation of Human Papillomavirus Cervical Infection and Lymphoma Incidence: A Clinical and Pathological Evaluation.

OBJECTIVE: Human papillomavirus (HPV) persistence is considered the main risk factor for neoplastic progression, and evidence suggests that regulatory T cells play an important role in the failure of viral elimination. Regulatory T cells may be involved in maintaining a microenvironment favourable for viral persistence and neoplasticity, through a deregulation of the local immune response. The association between altered immune function and the development of chronic infections, cancer (solid and haematological), and autoimmune diseases is documented in the literature. The purpose of this retrospective analysis was to evaluate the possible correlation between HPV cervical infection and lymphoma incidence in women attending colposcopy due to an abnormal Pap smear during a period of 15 years. DESIGN: This is a cross-sectional study. PARTICIPANTS: We investigated retrospectively the incidence of haematological diseases in women aged 21-84 with an abnormal Pap smear who referred to our centre between 2004 and 2019. SETTING: This study was conducted at the university hospital. METHODS: In our analysis, we included women with diagnoses of HL and NHL after the detection of abnormal Pap smears and HPV infections. We excluded patients with a diagnosis of lymphoma preceding the date of the abnormal Pap smear and HPV test. RESULTS: We divided the patients into two groups in order to analyse the standard incidence ratio (SIR): HL patients (19/7,064, 0.26%) and NHL patients (22/7,064, 0.31%). In our sample, we reported a significant risk of developing lymphoma compared to the general population, both for HL and NHL disease, at age <45 years. Regarding HL, the SIR of disease in women <45 years was 4.886 (95% CI 2.775-9.6029) and in women between 45 and 59 years was 2.612 (95% CI 0.96-7.108804). On the other hand, for NHL in women <45 years, we reported an SIR of about 3.007 (95%, CI 1.273-7.101575), in women aged 45-59 years, the SIR was 4.291 (95% CI 2.444-7.534399), and in women aged 60-74 years, the SIR was 3.283 (95% CI 1.054-10.22303). LIMITATIONS: This retrospective analysis was conducted in a single centre in Northern Italy and did not consider all interregional differences existing in the country in terms of HPV genotypes, ethnicity, and population characteristics. Regarding the analysis of SIR for HL and NHL, we did not divide the disease into subtypes because of the small sample of cases. Finally, we considered in our analysis only women with an abnormal Pap smear and not the general population. CONCLUSIONS: Women with chronic and persistent HPV infections may have a higher relative risk of developing lymphoma. This possible association may be caused by the deregulation of the immune system response against HPV and the failure of viral clearance, especially in younger women.

Invasive lobular carcinoma metastasis to pancreas mimicking pancreatic signet ring cell carcinoma: A case report and systematic review of the literature.

Metastasis to the gastrointestinal tract is a rare instance in the natural history of breast cancer, usually in association with lobular histology and widespread dissemination of disease. We report the case of a 74-year-old woman with a history of invasive lobular carcinoma presenting with a pancreatic metastasis mimicking a primary pancreatic adenocarcinoma; we also present a systematic review of the relevant literature. The presentation of pancreatic metastasis in the setting of breast cancer is unspecific, and histology is of paramount importance for a correct diagnosis; surgical metastasectomy could be of some benefit in the correct clinical setting.

Clinical and Histopathological Features of an Italian Monocentric Series of Primary Small Bowel T-Cell Lymphomas.

The gastrointestinal (GI) tract is the most common extranodal site of occurrence of non-Hodgkin lymphomas. Most GI lymphomas are of B-cell lineage, while T-cell lymphomas are less frequent. The aim of our retrospective study was to depict the clinical-pathological profile of a series of patients affected by intestinal T-cell lymphomas (ITCL) and possibly define hallmarks of these neoplasms. A total of 28 patients were included: 17 enteropathy-associated T-cell lymphomas (EATL), 5 monomorphic epitheliotropic T-cell lymphomas (MEITL), 3 indolent T-cell lymphoproliferative disorders of the gastrointestinal tract (ITCLDGT), and 3 intestinal T-cell lymphomas not otherwise specified (ITCL-NOS). Celiac disease (CD) was diagnosed in around 70% of cases. Diagnosis of EATL showed a significant correlation with CD30 expression, whereas MEITL with angiotropism and CD56 positivity. ITCLDGT cases showed plasma cells infiltration. Peripheral lymphocytosis, the absence of a previous diagnosis of CD, an advanced Lugano clinical stage, and the histological subtype ITCL-NOS were significantly associated with worse survival at multivariate analysis. Our findings about the epidemiological, clinical, and histopathological features of ITCL were in line with the current knowledge. Reliable prognostic tools for these neoplasms are still lacking but according to our results lymphocytosis, diagnosis of CD, Lugano clinical stage, and histological subtype should be considered for patient stratification.

T-Cells Subsets in Castleman Disease: Analysis of 28 Cases Including Unicentric, Multicentric and HHV8-Related Clinical Forms.

Castleman disease (CD) is a rare lymphoproliferative disorder that includes various clinico-pathological subtypes. According to clinical course, CD is divided into unicentric CD (UCD) and multicentric CD (MCD). MCD is further distinguished based on the etiological driver in herpes virus-8-related MCD (that can occur in the setting of HIV); in MCD associated with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes); and idiopathic MCD (iMCD). The latter can also be divided in iMCD-TAFRO (thrombocytopenia, anasarca, fever, myelofibrosis, organomegaly) and iMCD not otherwise specified. To date, CD pathogenesis is still uncertain, but CD may represent the histological and clinical result of heterogeneous pathomechanisms. Transcriptome investigations in CD lymph nodes have documented the expression and up-regulation of different cytokines; furthermore, few recent studies have shown alterations of different T-cell subsets in CD patients, suggesting a possible role of the nodal microenvironment in CD development. On this basis, our study aimed to investigate the distribution of T-cell subsets in the clinico-pathological spectrum of CD. We evaluated the CD4/CD8 ratio and the number of T-regulatory (T-reg) FOXP3+ cells in 28 CD cases. In total, 32% of cases showed a decreased CD4/CD8 ratio due to increased CD8+ T-cells, including both UCD, iMCD, and HHV8+ MCD cases. The T-reg subset analysis revealed a statistically significant (p < 0.0001) lower mean number of FOXP3+ T-reg cells in CD cases when compared with non-specific reactive lymph nodes. We did not find statistically significant differences in T-reg numbers between the different CD subtypes. These findings may suggest that alterations in T-cell subpopulations that can lead to disruption of immune system control may contribute to the numerous changes in different cellular compartments that characterize CD.

The molecular landscape of breast mucoepidermoid carcinoma.

Mucoepidermoid carcinoma (MEC) of the breast is an extremely rare salivary gland-type tumor characterized by epidermoid, basaloid, intermediate, and/or mucinous cells arranged in solid and cystic patterns. Despite their triple-negative phenotype, breast MECs are generally considered low-risk malignancies but their biology is largely unexplored; therefore, guidelines for clinical management are lacking. Here, we sought to characterize the molecular landscape of breast MECs. Thirteen cases were histologically reviewed, characterized for tumor-infiltrating lymphocytes (TILs), and were subjected to immunohistochemistry for programmed death-ligand 1 (PD-L1, clone 22C3), EGFR, and amphiregulin (AREG). Rearrangements in MAML2 and EWSR1 were investigated by fluorescent in situ hybridization. Targeted next-generation sequencing of 161 genes was performed on eight cases. Most MECs had low histological grade (n = 10, 77%), with the presence of TILs (n = 9/12; 75%) and PD-L1 combined positive score ranging from 10 to 20 (n = 4/6; 67%). All cases showed EGFR and AREG overexpression and were fusion negative. Enrichment of genetic alterations was observed in PI3K/AKT/mTOR and cell cycle regulation pathways, while only one case harbored TP53 mutations. This is the first study providing extensive molecular data on breast MECs and the largest collection of cases available to date in the literature. Breast MECs lack TP53 mutations found in high-grade forms of triple-negative breast cancers and MAML2 or EWSR1 rearrangements pathognomonic of salivary MECs. Triple-negativity and PD-L1 positivity suggest a window of opportunity for immunotherapy in these patients. The EGFR/AREG axis activation, coupled with the mutational patterns in PI3K/AKT/mTOR and cell cycle pathways warrants caution in considering MECs as low-risk neoplasms.

Concordance of immunohistochemistry for predictive and prognostic factors in breast cancer between biopsy and surgical excision: a single-centre experience and review of the literature.

PURPOSE: Accurate evaluation of breast cancer on bioptic samples is of fundamental importance to guide therapeutic decisions, especially in the neoadjuvant or metastatic setting. We aimed to assess concordance for oestrogen receptor (ER), progesterone receptor (PR), c-erbB2/HER2 and Ki-67. We also reviewed the current literature to evaluate our results in the context of the data available at present. METHODS: We included patients who underwent both biopsy and surgical resection for breast cancer at San Matteo Hospital, Pavia, Italy, between January 2014 and December 2020. ER, PR, c-erbB2, and Ki-67 immunohistochemistry concordance between biopsy and surgical specimen was evaluated. ER was further analysed to include the recently defined ER-low-positive in our analysis. RESULTS: We evaluated 923 patients. Concordance between biopsy and surgical specimen for ER, ER-low-positive, PR, c-erbB2 and Ki-67 was, respectively, 97.83, 47.8, 94.26, 68 and 86.13%. Cohen's κ for interobserver agreement was very good for ER and good for PR, c-erbB2 and Ki-67. Concordance was especially low (37%) in the c-erbB2 1 + category. CONCLUSION: Oestrogen and progesterone receptor status can be safely assessed on preoperative samples. The results of this study advise caution in interpreting biopsy results regarding ER-low-positive, c-erbB2/HER and Ki-67 results due to a still suboptimal concordance. The low concordance for c-erbB2 1 + cases underlines the importance of further training in this area, in the light of the future therapeutic perspectives.

Tissue fluidification promotes a cGAS-STING cytosolic DNA response in invasive breast cancer.

The process in which locally confined epithelial malignancies progressively evolve into invasive cancers is often promoted by unjamming, a phase transition from a solid-like to a liquid-like state, which occurs in various tissues. Whether this tissue-level mechanical transition impacts phenotypes during carcinoma progression remains unclear. Here we report that the large fluctuations in cell density that accompany unjamming result in repeated mechanical deformations of cells and nuclei. This triggers a cellular mechano-protective mechanism involving an increase in nuclear size and rigidity, heterochromatin redistribution and remodelling of the perinuclear actin architecture into actin rings. The chronic strains and stresses associated with unjamming together with the reduction of Lamin B1 levels eventually result in DNA damage and nuclear envelope ruptures, with the release of cytosolic DNA that activates a cGAS-STING (cyclic GMP-AMP synthase-signalling adaptor stimulator of interferon genes)-dependent cytosolic DNA response gene program. This mechanically driven transcriptional rewiring ultimately alters the cell state, with the emergence of malignant traits, including epithelial-to-mesenchymal plasticity phenotypes and chemoresistance in invasive breast carcinoma.

Pathologic Findings at Risk Reducing Surgery in BRCA and Non-BRCA Mutation Carriers: A Single-Center Experience.

Risk-reducing surgery (RRS) is recommended in BRCA-mutated carriers because of their increased risk of developing ovarian cancer, while its role is still discussed for women harboring mutations in non-BRCA homologous repair genes. The aim of this study was to retrospectively evaluate the occurrence of pathological findings in a high-risk population undergoing RRS in San Matteo Hospital, Pavia between 2012 and 2022, and correlate their genetic and clinical outcomes, comparing them with a control group. The final cohort of 190 patients included 85 BRCA1, 63 BRCA2, 11 CHEK2, 7 PALB2, 4 ATM, 1 ERCC5, 1 RAD51C, 1 CDH1, 1 MEN1, 1 MLH1 gene mutation carriers and 15 patients with no known mutation but with strong familial risk. Occult invasive serous carcinoma (HGSC) and serous tubal intraepithelial carcinoma (STIC) were diagnosed in 12 (6.3%) women, all of them BRCA carriers. No neoplastic lesion was diagnosed in the non-BRCA group, in women with familial risk, or in the control group. Oral contraceptive use and age ≤45 at surgery were both found to be favorable factors. While p53 signature and serous tubal intraepithelial lesion (STIL) were also seen in the control group and in non-BRCA carriers, STIC and HGSC were only found in BRCA1/2 mutation carriers.

The Bio-Diversity and the Role of Gut Microbiota in Postmenopausal Women with Luminal Breast Cancer Treated with Aromatase Inhibitors: An Observational Cohort Study.

The interactions between aromatase inhibitors (AI) in breast cancer (BC) and gut microbiota (GM) have not been completely established yet. The aim of the study is to evaluate the bio-diversity of GM and the relationship between GM, inflammation and tumor-infiltrating lymphocytes (TILs) in postmenopausal women with BC during adjuvant AI treatment compared to women with disease relapse during or after one year of AI therapy ("endocrine-resistant"). We conducted a monocenter observational case-control study. Eighty-four women with BC (8 cases, 76 controls) were enrolled from 2019 to 2021. We observed a significant difference in the mean microbial abundance between the two groups for the taxonomic rank of order (p 0.035) and family (p 0.029); specifically, the case group showed higher diversity than the control group. Veillonella reached its maximum abundance in cases (p 0.022). Cytokine levels were compared among the groups created considering the TILs levels. We obtained a statistically significant difference (p 0.045) in IL-17 levels among the groups, with patients with low TILs levels showing a higher median value for IL-17 (0.15 vs. 0.08 pg/mL). Further studies about the bio-diversity in women with BC may lead to the development of new biomarkers and targeted interventions.

Case Report: A rare case of small bowel obstruction secondary to plasma cell myeloma.

Gastrointestinal (GI) involvement of plasma cell neoplasms is extremely rare. Herein, we describe the case of a 74-year-old Caucasian woman who came to our attention with abdominal pain, food vomiting, and weight loss of 10 kg over 1 year. A computed tomography scan of the abdomen revealed circumferential thickening of terminal ileum, for which the patient underwent an urgent 20-cm-long ileal resection. Histopathological and immunophenotypic analysis revealed a plasma cell neoplasm of the ileum. Subsequent investigations found a serum monoclonal immunoglobulin A component, an osteolytic lesion of the left jaw, and a clonal bone marrow plasma cell infiltrate carrying 1q21 amplification. Given the final diagnosis of plasma cell myeloma (PCM), the patient underwent a VMD (bortezomib, melphalan, and dexamethasone) chemotherapy regimen, achieving a complete remission after a 12-month treatment. For disease relapse, two further chemotherapy regimens were later attempted. At the last follow-up 4 years after the diagnosis, the patient is still alive. This case draws attention to the extramedullary presentation of plasma cell neoplasms, even if rare, as a prompt diagnosis seems to result in a better prognosis. In addition, it highlights the relevance of a multidisciplinary approach, involving gastroenterologists, hematologists, and pathologists, to the diagnosis and management of these neoplasms.

Genetic and phenotypic attributes of splenic marginal zone lymphoma.

Splenic marginal zone B-cell lymphoma (SMZL) is a heterogeneous clinico-biological entity. The clinical course is variable, multiple genes are mutated with no unifying mechanism, and essential regulatory pathways and surrounding microenvironments are diverse. We sought to clarify the heterogeneity of SMZL by resolving different subgroups and their underlying genomic abnormalities, pathway signatures, and microenvironment compositions to uncover biomarkers and therapeutic vulnerabilities. We studied 303 SMZL spleen samples collected through the IELSG46 multicenter international study (NCT02945319) by using a multiplatform approach. We carried out genetic and phenotypic analyses, defined self-organized signatures, validated the findings in independent primary tumor metadata and in genetically modified mouse models, and determined correlations with outcome data. We identified 2 prominent genetic clusters in SMZL, termed NNK (58% of cases, harboring NF-κB, NOTCH, and KLF2 modules) and DMT (32% of cases, with DNA-damage response, MAPK, and TLR modules). Genetic aberrations in multiple genes as well as cytogenetic and immunogenetic features distinguished NNK- from DMT-SMZLs. These genetic clusters not only have distinct underpinning biology, as judged by differences in gene-expression signatures, but also different outcomes, with inferior survival in NNK-SMZLs. Digital cytometry and in situ profiling segregated 2 basic types of SMZL immune microenvironments termed immune-suppressive SMZL (50% of cases, associated with inflammatory cells and immune checkpoint activation) and immune-silent SMZL (50% of cases, associated with an immune-excluded phenotype) with distinct mutational and clinical connotations. In summary, we propose a nosology of SMZL that can implement its classification and also aid in the development of rationally targeted treatments.

Genetic Characterization and Clinical Features of Helicobacter pylori Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphoma.

BACKGROUND: In Western countries, the prevalence of gastric mucosa-associated lymphoid tissue (MALT) lymphoma has declined over the last three decades. Contemporaneously, H. pylori negative gastric MALT lymphoma is increasingly encountered, and their genetic basis and clinical features remain elusive. METHODS: A total of 57 cases of H. pylori negative gastric MALT lymphoma were reviewed and investigated for chromosome translocation by fluorescence in-situ hybridization and for somatic mutations by the targeted sequencing of 93 genes. RESULTS: MALT1 translocation, most likely t(11;18)(q21;q21)/BIRC3-MALT1, was detected in 39% (22/57) cases, and IGH translocation was further seen in 12 MALT1-negative cases, together accounting for 60% of the cohort. Targeted sequencing was successful in 35 cases, and showed frequent mutations in NF-κB signaling pathways (TNFAIP3 = 23%, CARD11 = 9%, MAP3K14 = 9%), together affecting 14 cases (40%). The NF-κB pathway mutations were mutually exclusive from MALT1, albeit not IGH translocation, altogether occurring in 86% of cases. There was no significant correlation between the genetic changes and clinicopathological parameters. The patients showed a median of progression-free survival (PFS) of 66.3 months, and a significant superior PFS when treated with systemic versus antibiotic therapy (p = 0.004). CONCLUSION: H. pylori negative gastric MALT lymphoma is characterized by highly frequent genetic changes in the NF-κB signaling pathways.

Complete Removal of the Lesion as a Guidance in the Management of Patients with Breast Ductal Carcinoma In Situ.

Background: Considering highly selected patients with ductal carcinoma in situ (DCIS), active surveillance is a valid alternative to surgery. Our study aimed to show the reliability of post-biopsy complete lesion removal, documented by mammogram, as additional criterion to select these patients. Methods: A total of 2173 vacuum-assisted breast biopsies (VABBs) documented as DCIS were reviewed. Surgery was performed in all cases. We retrospectively collected the reports of post-VABB complete lesion removal and the histological results of the biopsy and surgery. We calculated the rate of upgrade of DCIS identified on VABB upon excision for patients with post-biopsy complete lesion removal and for those showing residual lesion. Results: We observed 2173 cases of DCIS: 408 classified as low-grade, 1262 as intermediate-grade, and 503 as high-grade. The overall upgrading rate to invasive carcinoma was 15.2% (330/2173). The upgrade rate was 8.2% in patients showing mammographically documented complete removal of the lesion and 19% in patients without complete removal. Conclusion: The absence of mammographically documented residual lesion following VABB was found to be associated with a lower upgrading rate of DCIS to invasive carcinoma on surgical excision and should be considered when deciding the proper management DCIS diagnosis.

Double expressor and double/triple hit status among primary cutaneous diffuse large B-cell lymphoma: a comparison between leg type and not otherwise specified subtypes.

Primary cutaneous diffuse large B-cell lymphomas (pcDLBCLs) are rare hematological neoplasms. The pcDLBCL category includes primary cutaneous large B-cell lymphoma leg type (pcDLBCL-LT), characterized by a particularly unfavorable outcome, and primary cutaneous large B-cell lymphoma not otherwise specified (pcDLBCL-NOS), a widely debated subentity with a more indolent course. The negative prognostic impact of double expressor status (DE status, given by coexpression of MYC and BCL2) and double hit/triple hit status (DH/TH status, given by translocations of MYC and BCL2 and/or BCL6) in nodal DLBCL is well known; however, no unanimous conclusions regarding relevance of DE and DH/TH status have been reached in pcDLBCL. Therefore, our purpose has been to investigate the presence and prognostic relevance of DE and DH/TH status among a retrospective multicentric cohort of 16 cases of pcDLBCL-LT and 17 cases of pcDLBCL-NOS. All cases were thoroughly reevaluated, both on a morphological and immunohistochemical level, and tested by means of fluorescence in situ hybridization for MYC, BCL2 and BCL6 rearrangements. DE status was observed in 69% of pcDLBCL-LT cases and in 24% of pcDLBCL-NOS cases; however, it did not impact prognosis in any of the groups examined. Combining molecular results, we highlighted a relevant fraction of DH pcDLBCL cases (three pcDLBCL-LT cases and one pcDLBCL-NOS case) and the very first case of TH pcDLBCL-LT reported to date. All DH cases were characterized by MYC and BCL6 rearrangements. Overall, DH/TH cases represented 15% (5/33) of all pcDLBCLs and were mostly pcDLBCL-LT. DH/TH status and DH status alone were associated with poorer overall survival and disease-specific survival (both p < 0.05) among all pcDLBCLs, without reaching statistical significance in the pcDLBCL-LT and pcDLBCL-NOS groups. In conclusion, MYC, BCL2, and BCL6 cytogenetical testing could be useful in identifying a putative subset of more aggressive pcDLBCLs, although this observation has to be confirmed by further studies.