Disease-biased and shared characteristics of the immunoglobulin gene repertoires in marginal zone B cell lymphoproliferations.

The B cell receptor immunoglobulin (Ig) gene repertoires of marginal zone (MZ) lymphoproliferations were analyzed in order to obtain insight into their ontogenetic relationships. Our cohort included cases with MZ lymphomas (n = 488), i.e. splenic (SMZL), nodal (NMZL) and extranodal (ENMZL), as well as provisional entities (n = 76), according to the WHO classification. The most striking Ig gene repertoire skewing was observed in SMZL. However, restrictions were also identified in all other MZ lymphomas studied, particularly ENMZL, with significantly different Ig gene distributions depending on the primary site of involvement. Cross-entity comparisons of the MZ Ig sequence dataset with a large dataset of Ig sequences (MZ-related or not; n = 65 837) revealed four major clusters of cases sharing homologous ('public') heavy variable complementarity-determining region 3. These clusters included rearrangements from SMZL, ENMZL (gastric, salivary gland, ocular adnexa), chronic lymphocytic leukemia, but also rheumatoid factors and non-malignant splenic MZ cells. In conclusion, different MZ lymphomas display biased immunogenetic signatures indicating distinct antigen exposure histories. The existence of rare public stereotypes raises the intriguing possibility that common, pathogen-triggered, immune-mediated mechanisms may result in diverse B lymphoproliferations due to targeting versatile progenitor B cells and/or operating in particular microenvironments. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

A Unique Case of Primary Extranodal Marginal Zone Lymphoma of the Anal Canal.

Marginal zone lymphomas represent approximately 10-12% of all B-cell lymphomas. Extranodal marginal zone lymphomas (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphomas are the most common subtype. Almost half of all MALT lymphomas arise in the gastrointestinal (GI) tract and, while the stomach is the most common site of GI involvement, the small and large intestines can also be involved. Rare cases of MALT lymphoma involving the rectum have been reported; however, to our knowledge, involvement of the anal canal has never been reported in the literature. Here, we describe a unique case of MALT lymphoma of the anal canal. Infectious agents have been implicated in the pathogenesis of MALT lymphomas, possibly through persistent antigenic stimulation of the area; however, in our case no such infection was documented.

Numerous Ontogenetic Roads to Mantle Cell Lymphoma: Immunogenetic and Immunohistochemical Evidence.

To obtain insight into the ontogeny of mantle cell lymphoma (MCL), we assessed 206 patients from a morphological, immunohistochemical, and immunogenetic perspective. Our series included nodal (n = 151), extranodal (n = 28), and primary splenic (n = 27) MCL cases. Skewing of the immunoglobulin heavy variable (IGHV) gene repertoire was noted, with only four IGHV genes accounting for 46% of cases and approximately 70% of cases (107/154) bearing an imprint of somatic hypermutation (SHM) ranging from minimal to pronounced. Interestingly, a distinctive immunophenotypic and immunogenetic profile was identified for primary splenic MCL, which was enriched for DBA.44-positive cases (P < 0.001) and used the IGHV1-8 gene more frequently (P = 0.02) compared to nodal or extranodal cases, alluding to distinct immunopathogenetic and antigen selection processes. Expression of CD27 (considered a marker of activated B cells) was generally dissociated from SHM and was more prevalent in cases with no or minimal/borderline SHM. These findings support the idea that antigen drive is relevant for most MCL cases, although the specific antigens and the precise location of affinity maturation remain to be elucidated. Moreover, they raise the intriguing hypothesis of multiple cellular origins for MCL.

Frequent NFKBIE deletions are associated with poor outcome in primary mediastinal B-cell lymphoma.

We recently reported a truncating deletion in the NFKBIE gene, which encodes IκBε, a negative feedback regulator of NF-κB, in clinically aggressive chronic lymphocytic leukemia (CLL). Because preliminary data indicate enrichment of NFKBIE aberrations in other lymphoid malignancies, we screened a large patient cohort (n = 1460) diagnosed with different lymphoid neoplasms. While NFKBIE deletions were infrequent in follicular lymphoma, splenic marginal zone lymphoma, and T-cell acute lymphoblastic leukemia (<2%), slightly higher frequencies were seen in diffuse large B-cell lymphoma, mantle cell lymphoma, and primary central nervous system lymphoma (3% to 4%). In contrast, a remarkably high frequency of NFKBIE aberrations (46/203 cases [22.7%]) was observed in primary mediastinal B-cell lymphoma (PMBL) and Hodgkin lymphoma (3/11 cases [27.3%]). NFKBIE-deleted PMBL patients were more often therapy refractory (P = .022) and displayed inferior outcome compared with wild-type patients (5-year survival, 59% vs 78%; P = .034); however, they appeared to benefit from radiotherapy (P =022) and rituximab-containing regimens (P = .074). NFKBIE aberrations remained an independent factor in multivariate analysis (P = .003) and when restricting the analysis to immunochemotherapy-treated patients (P = .008). Whole-exome sequencing and gene expression profiling verified the importance of NF-κB deregulation in PMBL. In summary, we identify NFKBIE aberrations as a common genetic event across B-cell malignancies and highlight NFKBIE deletions as a novel poor-prognostic marker in PMBL.

Clonal B-cell lymphocytosis exhibiting immunophenotypic features consistent with a marginal-zone origin: is this a distinct entity?

The biological and clinical significance of a clonal B-cell lymphocytosis with an immunophenotype consistent with marginal-zone origin (CBL-MZ) is poorly understood. We retrospectively evaluated 102 such cases with no clinical evidence to suggest a concurrent MZ lymphoma. Immunophenotyping revealed a clonal B-cell population with Matutes score ≤2 in all cases; 19/102 were weakly CD5 positive and all 35 cases tested expressed CD49d. Bone marrow biopsy exhibited mostly mixed patterns of small B-lymphocytic infiltration. A total of 48/66 (72.7%) cases had an abnormal karyotype. Immunogenetics revealed overusage of the IGHV4-34 gene and somatic hypermutation in 71/79 (89.8%) IGHV-IGHD-IGHJ gene rearrangements. With a median follow-up of 5 years, 85 cases remain stable (group A), whereas 17 cases (group B) progressed, of whom 15 developed splenomegaly. The clonal B-cell count, degree of marrow infiltration, immunophenotypic, or immunogenetic findings at diagnosis did not distinguish between the 2 groups. However, deletions of chromosome 7q were confined to group A and complex karyotypes were more frequent in group B. Although CBL-MZ may antedate SMZL/SLLU, most cases remain stable over time. These cases, not readily classifiable within the World Heath Organization classification, raise the possibility that CBL-MZ should be considered as a new provisional entity within the spectrum of clonal MZ disorders.

Genetic Characterization of Primary Mediastinal B-Cell Lymphoma: Pathogenesis and Patient Outcomes.

PURPOSE: Primary mediastinal large B-cell lymphoma (PMBCL) is a rare aggressive lymphoma predominantly affecting young female patients. Large-scale genomic investigations and genetic markers for risk stratification are lacking. PATIENTS AND METHODS: To elucidate the full spectrum of genomic alterations, samples from 340 patients with previously untreated PMBCL were investigated by whole-genome (n = 20), whole-exome (n = 78), and targeted (n = 308) sequencing. Statistically significant prognostic variables were identified using a multivariable Cox regression model and confirmed by L1/L2 regularized regressions. RESULTS: Whole-genome sequencing revealed a commonly disrupted p53 pathway with nonredundant somatic structural variations (SVs) in TP53-related genes (TP63, TP73, and WWOX) and identified novel SVs facilitating immune evasion (DOCK8 and CD83). Integration of mutation and copy-number data expanded the repertoire of known PMBCL alterations (eg, ARID1A, P2RY8, and PLXNC1) with a previously unrecognized role for epigenetic/chromatin modifiers. Multivariable analysis identified six genetic lesions with significant prognostic impact. CD58 mutations (31%) showed the strongest association with worse PFS (hazard ratio [HR], 2.52 [95% CI, 1.50 to 4.21]; P < .001) and overall survival (HR, 2.33 [95% CI, 1.14 to 4.76]; P = .02). IPI high-risk patients with mutated CD58 demonstrated a particularly poor prognosis, with 5-year PFS and OS rates of 41% and 58%, respectively. The adverse prognostic significance of the CD58 mutation status was predominantly observed in patients treated with nonintensified regimens, indicating that dose intensification may, to some extent, mitigate the impact of this high-risk marker. By contrast, DUSP2-mutated patients (24%) displayed durable responses (PFS: HR, 0.2 [95% CI, 0.07 to 0.55]; P = .002) and prolonged OS (HR, 0.11 [95% CI, 0.01 to 0.78]; P = .028). Upon CHOP-like treatment, these patients had very favorable outcome, with 5-year PFS and OS rates of 93% and 98%, respectively. CONCLUSION: This large-scale genomic characterization of PMBCL identified novel treatment targets and genetic lesions for refined risk stratification. DUSP2 and CD58 mutation analyses may guide treatment decisions between rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone and dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab.

Case report: The devil was hidden in the mastocytes - an unusually fulminant case of indolent systemic mastocytosis in a 45-year-old patient, missed for almost 20 years.

Indolent systemic mastocytosis (ISM) represents the most common form of SM, typically following a slow clinical course. While anaphylactic reactions may come up in the life course of an ISM patient, these are often moderate and do not pose a threat to patient's health. Here, we present an undiagnosed case of ISM with recurrent severe anaphylactic episodes following consumption of food and emotional stress. One of these episodes led to anaphylactic shock, necessitating temporary mechanical ventilation and intensive care unit (ICU) support. Besides hypotension, a diffuse, itchy, red rash was the only notable clinical finding. Upon recovery, we found abnormally high baseline serum tryptase level as well as 10% bone marrow (BM) infiltration by multifocal, dense clusters of CD117+/mast cell tryptase+/CD25+ mast cells (MCs), consolidating the diagnosis of ISM. Prophylactic treatment with a histamine receptor antagonist was initiated, resulting in milder episodes thereafter. Diagnosis of ISM requires a high level of suspicion; its prompt recognition and treatment are important in preventing potentially life-threatening anaphylactic episodes.

Capecitabine-associated enterocolitis: Narrative literature review of a rare adverse event and a case presentation.

Capecitabine is an oral 5-fluorouracil prodrug with antimetabolite activity commonly used in advanced colorectal and breast cancer. It presents with a generally good toxicity profile and most of the adverse events can be managed effectively. Enterocolitis is a rare, under-reported, but potentially fatal adverse event associated with capecitabine use. To the best of our knowledge, there are 21 cases of capecitabine-related enterocolitis reported in the literature. We herein present a narrative literature review of enteritis/colitis cases associated with capecitabine use, with highlight to the most common clinical presentation, common imaging and microscopic findings and management approach. We furthermore present a case of severe capecitabine-related enteritis.

Frequent ZNF217 mutations lead to transcriptional deregulation of interferon signal transduction via altered chromatin accessibility in B cell lymphoma.

Recent exome-wide studies discovered frequent somatic mutations in the epigenetic modifier ZNF217 in primary mediastinal B cell lymphoma (PMBCL) and related disorders. As functional consequences of ZNF217 alterations remain unknown, we comprehensively evaluated their impact in PMBCL. Targeted sequencing identified genetic lesions affecting ZNF217 in 33% of 157 PMBCL patients. Subsequent gene expression profiling (n = 120) revealed changes in cytokine and interferon signal transduction in ZNF217-aberrant PMBCL cases. In vitro, knockout of ZNF217 led to changes in chromatin accessibility interfering with binding motifs for crucial lymphoma-associated transcription factors. This led to disturbed expression of interferon-responsive and inflammation-associated genes, altered cell behavior, and aberrant differentiation. Mass spectrometry demonstrates that ZNF217 acts within a histone modifier complex containing LSD1, CoREST and HDAC and interferes with H3K4 methylation and H3K27 acetylation. Concluding, our data suggest non-catalytic activity of ZNF217, which directs histone modifier complex function and controls B cell differentiation-associated patterns of chromatin structure.

Splenic diffuse red pulp small B-cell lymphoma: revision of a series of cases reveals characteristic clinico-pathological features.

BACKGROUND: Splenic diffuse red pulp small B-cell lymphoma is an uncommon B-cell lymphoma, now recognized as a provisional entity in the 2008 update of the WHO Classification. Additional work is required to review this entity and establish its diagnostic features. DESIGN AND METHODS: We have retrospectively analyzed the disease features in a highly selected series of 17 patients diagnosed as splenic diffuse red pulp small B-cell lymphoma. RESULTS: The median age was 65.5 years (range 40-79 years) and there was a predominance of males (male/female ratio: 2.4). Clinical manifestations were mainly derived from splenomegaly. Splenectomy was the front-line treatment in 11 symptomatic patients; the remaining 6 received chemotherapy initially followed by splenectomy. After a mean follow-up of 72 months, the five-year overall survival was 93%. All cases showed a purely diffuse pattern of splenic infiltration by monomorphous small cells with small round nuclei and pale cytoplasm. All bone marrow biopsies showed tumoral infiltration, with intrasinusoidal infiltration. Peripheral blood cells were small to medium-sized, with clumped chromatin and round nuclear outline and villous cytoplasm. Neoplastic cells had a CD20(+), CD23(-), bcl6(-), Annexin A1- phenotype, with frequent expression of DBA44+ (15/17) and IgG (10/15). FCM data had a B-cell phenotype (CD19(+), CD20(+), CD22(+)) with FMC7 (10/11) and CD11c (5/8) expression. Clonal IgH rearrangement studies in 4 cases showed IgVH mutations in all cases, without VH1.2 usage. CONCLUSIONS: Our data suggest that splenic diffuse red pulp small B-cell lymphoma is a distinct entity with morphological and immunophenotypical features that differ from those of other splenic lymphomas.

Brain and bone marrow metastases from rectal cancer.

Despite the development of new treatment options based on the molecular characterization of colorectal cancer, 20% of patients present de novo metastatic disease, whereas 30-40% of patients who receive curative treatment relapse during follow up. Herein, we report 2 cases with rectal cancer that developed uncommon sites of metastasis; the first patient had an isolated breast metastasis, while the second patient developed bone marrow infiltration with synchronous brain metastases. In order to evaluate the uncommon metastatic pattern of rectal cancer, we detected and enumerated circulating tumor cells (CTCs) using both immunofluorescence and real-time reverse transcriptase polymerase chain reaction in these patients' peripheral blood. The procedure revealed the presence of CTCs, positive for CEACAM5 but negative for epithelial phenotype (EpCAM-), that might explain the patients' metastatic potential and survival.

Hodgkin Lymphoma Mimicking Inflammatory Breast Carcinoma: A Rare Case with Diagnostic Challenge and Novel Treatment.

Extranodal Hodgkin lymphoma involving the breast is infrequent. Most cases reported in the literature were diagnosed by histology after lumpectomy. We present a Hodgkin lymphoma mimicking inflammatory breast carcinoma in a 57-year-old woman. The diagnosis was performed by fine-needle aspiration (FNA) of the breast lesion and the axillary lymph nodes with rapid on-site evaluation followed by immunocytochemistry, and it was confirmed by histology. The patient after first-line chemotherapy developed relapse/refractory disease. Salvage chemotherapy regimens were applied with poor results and severe toxicity. Total remission was achieved with monotherapy of brentuximab vedotin, a novel anti-CD30-targeted antibody drug conjugate. This is a unique case of breast HL with misleading clinical presentation initially diagnosed by cytology. FNA as a minimally invasive diagnostic tool was crucial in avoiding unnecessary breast surgery and further delay of chemotherapy. It is also the first report highlighting the importance of this novel immunotherapy in the management of refractory Hodgkin lymphoma with breast involvement.

Correlation of androgen receptor status, neuroendocrine differentiation and angiogenesis with time-to-biochemical failure after radical prostatectomy in clinically localized prostate cancer.

UNLABELLED: The aim of this study was to elucidate the prognostic value of the immunohistochemical detection of the androgen receptor (AR) status, the chromogranin A assessment of neuroendocrine differentiation (NED) and the CD34 assessment of microvessel density (MVD) with time-to-biochemical failure among surgically treated patients with clinically localized prostate cancer. PATIENTS AND METHODS: Surgical specimens from 130 patients with clinically localized prostate cancer, treated with radical prostatectomy, were analyzed by immunohistochemistry on paraffin tissue sections. Full-length follow-up records were available for 94 patients. RESULTS: Biochemical failure was observed in 37% of these patients. A statistically significant inverse relationship was observed between AR status and: (i) seminal vesicle invasion and (ii) surgical margin infiltration. Positive association was also detected between NED and: (i) Gleason's score, (ii) extracapsular extension, (iii) seminal vesicle invasion, (iv) surgical margin infiltration and (v) tumour volume. In addition, MVD was related to: (i) Gleason score, (ii) extracapsular extension, (iii) seminal vesicle invasion, (iv) pelvic lymph node metastasis and (v) tumour volume. Kaplan-Meier survival curves confirmed that Gleason score, extracapsular extension, seminal vesicle invasion, pelvic lymph node metastasis, tumour volume, NED, MVD and coexistence of increased NED and MVD may be potential biochemical failure predictors. However, in the multivariate analysis, MVD was the only independent prognostic factor for biochemical failure. CONCLUSION: A high MVD index can estimate the risk for biochemical failure in clinically localized prostate cancer after radical prostatectomy.

Expression of DNA mismatch repair gene MSH2 in cytological material from lung cancer patients.

Mismatch repair genes encode for proteins responsible for the correction of bases incorrectly paired in the DNA. Loss of DNA mismatch repair activity has been associated with various cancers including tumors of the lung. In the present study, we have analyzed by immunocytochemistry the expression of MSH2 DNA repair gene in cytological material obtained by fine needle aspiration from a panel of 42 primary lung cancer patients. Specimens included 13 adenocarcinomas, 11 small cell carcinomas and 18 squamous cell carcinomas. Loss of expression or low expression was detected in 6 out of 13 (46%) adenocarcinomas and in 7 out of 18 (39%) of squamous cell carcinomas, although all 11 small cell carcinomas expressed MSH2. Our results suggest that loss of MSH2 expression is frequent in nonsmall cell carcinomas of the lung (P < 0.01, chi2 test). Evaluation of MSH2 expression can be applied for the screening of cytological material from fine needle aspirations from the lung.

An Immunogenetic Signature of Ongoing Antigen Interactions in Splenic Marginal Zone Lymphoma Expressing IGHV1-2*04 Receptors.

PURPOSE: Prompted by the extensive biases in the immunoglobulin (IG) gene repertoire of splenic marginal-zone lymphoma (SMZL), supporting antigen selection in SMZL ontogeny, we sought to investigate whether antigen involvement is also relevant post-transformation. EXPERIMENTAL DESIGN: We conducted a large-scale subcloning study of the IG rearrangements of 40 SMZL cases aimed at assessing intraclonal diversification (ID) due to ongoing somatic hypermutation (SHM). RESULTS: ID was identified in 17 of 21 (81%) rearrangements using the immunoglobulin heavy variable (IGHV)1-2*04 gene versus 8 of 19 (40%) rearrangements utilizing other IGHV genes (P= 0.001). ID was also evident in most analyzed IG light chain gene rearrangements, albeit was more limited compared with IG heavy chains. Identical sequence changes were shared by subclones from different patients utilizing the IGHV1-2*04 gene, confirming restricted ongoing SHM profiles. Non-IGHV1-2*04 cases displayed both a lower number of ongoing SHMs and a lack of shared mutations (per group of cases utilizing the same IGHV gene). CONCLUSIONS: These findings support ongoing antigen involvement in a sizable portion of SMZL and further argue that IGHV1-2*04 SMZL may represent a distinct molecular subtype of the disease.

Immunohistochemical detection of GHRH and its receptor splice variant 1 in primary human breast cancers.

OBJECTIVE: GHRH is secreted by the hypothalamus and, upon binding to specific GHRH receptors in the pituitary, stimulates growth hormone (GH) production and release from the pituitary. In addition to this neuroendocrine action, accumulated evidence implies additional roles for GHRH in carcinogenesis in non-pituitary tissues. In vitro and in vivo studies have shown that splice variant 1 (SV1) of the GHRH receptor, which is widely expressed in non-pituitary tissues and cancers, can mediate the proliferative effects of GHRH. The aim of the present study was to investigate the operation of an autocrine stimulatory loop between GHRH and SV1 in primary breast tumors. DESIGN: Fifty-three primary breast tumors were evaluated for GHRH and SV1 expression. METHODS: Expression of GHRH and SV1 was assessed by immunohistochemistry using anti-GHRH SV95 and anti-SV1 2317/5 polyclonal antibodies. RESULTS: About 40% of the specimens tested express GHRH and/or SV1 (approx. 25% each), while in 35% of these positive specimens co-expression of these antigens was detected (P<0.01). Furthermore, a correlation of GHRH, but not SV1, expression was detected in lobular compared with ductal carcinomas. CONCLUSIONS: These results constitute the first demonstration for the expression of GHRH and SV1 in primary breast cancers, and provide evidence for the operation of an autocrine stimulatory loop between GHRH and SV1 in primary cancers. Our findings indicate that GHRH analogs could have diagnostic and therapeutic applications for the management of breast cancer.

Plasmablastic lymphoma of the breast in an immunocompetent patient: long-lasting complete response induced by chemotherapy and autologous stem cell trasplantation.

BACKGROUND: Plasmablastic lymphoma (PBL) is a rare entity which is often causally related to infection by the Human Immunodeficiency Virus (HIV). Despite its predilection for oral cavity involvement, multiple cases of extra-oral involvement have been reported in the literature, more often among immunocompetent individuals. CASE REPORT: Herein we present the first case of primary PBL of the breast in an otherwise immunocompetent 36-year-old woman who was successfully treated with consolidation megatherapy and autologous stem cell transplantation. CONCLUSION: PBL carries a particularly poor prognosis and more intensive treatment is usually warranted. However, no treatment guidelines exist and treatment choices are made based on case reports and small retrospective case series.