Joost J. Oudejans

In breast cancer therapy, the indication for systemic therapy is typically based on prognostic markers from the surgical excision specimen. If such is unavailable, for instance prior to tumor ablation therapy, the indication for adjuvant systemic therapy may be assessed from pretreatment biopsies. The effect of differences in tumor characteristics between biopsy and excision specimen on agreement in indication for systemic therapy is, however, largely unknown. The aim of this study is to determine the agreement in eligibility for systemic therapy between preoperative and postoperative assessment. Secondly, to identify which patient-, tumor- or lymph node characteristics may influence this agreement. In this retrospective study, 300 consecutive female patients with primary invasive breast carcinoma on biopsy were included. Indication for systemic therapy was determined separately from biopsied tissue and from excision specimens using national guidelines based on adjuvant! online. Agreement was assessed, and patient-, tumor- and lymph node characteristics affecting agreement analyzed. Agreement in tumor characteristics between biopsy and excision specimen varied from high (ER-status: 99%), to lower (tumor grade: 62%, tumor size: 59%, and lymph node status: 67%). Without preoperative sentinel node biopsy (SNB), agreement on systemic therapy exists in 77% of patients (kappa = 0,547). Positive pretreatment indication for systemic therapy was highly indicative of the postoperative indication (PPV = 94%). Negative indication was, however, only indicative in 67% of patients. Conversely, with preoperative SNB, agreement on negative indication was raised to 89%. Agreement was especially high for ER-negative status, tumor grade 3, tumor size >2 cm, lymph node positivity at biopsy and a negative preoperative SNB. A positive indication for systemic therapy from biopsy is highly indicative for a positive indication from the excision specimen. When the indication is negative, additional stratification using preoperative SNB raises the agreement. Still, discordance occurs in 1 out of 10 patients.

Aims: In females, columnar cell lesions (CCLs) have been recognized as putative precursor lesions of low‐grade breast cancer, but their role in male breast carcinogenesis is as yet unclear.Methods and results: We reviewed surgical resections from males with breast cancer (n = 89), gynaecomastia (n = 20) and normal breast specimens from autopsies (n = 5) for the presence of CCL. In addition, we performed immunohistochemistry for cytokeratin 5/6 (CK5/6), CK14 and oestrogen receptor alpha (ER). In 19 of 89 resections (two DCIS cases and 17 invasive carcinoma), some individual ducts were found to contain cells with snouts on the luminal border but lacking further typical columnar cell lesion features. We mainly found three‐layered ductal epithelium, characteristic for gynaecomastia and confirmed by immunohistochemistry. Moreover, we found a few ducts in male breast cancer sections that were clonally negative for basal cytokeratins.Conclusion: We found no lesions with convincing CCL morphology at the periphery of invasive male breast cancers, in gynaecomastia or in normal male breast specimens. Although we cannot completely exclude the existence of CCLs in the male breast, these lesions seem to be very uncommon and are therefore unlikely to play a major role in male breast carcinogenesis.

Introduction: Epigenetic events are, along with genetic alteration, important in the development and progression of cancer. Promoter hypermethylation causes gene silencing and is thought to be an early event in carcinogenesis. The role of promoter hypermethylation in male breast cancer has not yet been studied. Methods: In a group of 108 male breast cancers, the methylation status of 25 genes was studied using methylation-specific multiplex ligation-dependent probe amplification. Methylation of more than 15% was regarded indicative for promoter hypermethylation. Methylation status was correlated with clinicopathological features, with patients' outcome and with 28 female breast cancer cases. Results: Promoter hypermethylation of the genes MSH6, WT1, PAX5, CDH13, GATA5 and PAX6 was seen in more than 50% of the cases, but was uncommon or absent in normal male breast tissue. High overall methylation status was correlated with high grade (P = 0.003) and was an independent predictor of poor survival (P = 0.048; hazard ratio 2.5). ESR1 and GSTP1 hypermethylation were associated with high mitotic count (P = 0.037 and P = 0.002, respectively) and high grade (both P = 0.001). No correlation with survival was seen for individual genes. Compared with female breast cancers (logistic regression), promoter hypermethylation was less common in a variety of genes, particularly ESR1 (P = 0.005), BRCA1 (P = 0.010) and BRCA2 (P < 0.001). The most frequently hypermethylated genes (MSH6, CDH13, PAX5, PAX6 and WT1) were similar for male and female breast cancer. Conclusion: Promoter hypermethylation is common in male breast cancer and high methylation status correlates with aggressive phenotype and poor survival. ESR1 and GSTP1 promoter hypermethylation seem to be involved in development and/or progression of high-grade male breast cancer. Although female and male breast cancer share a set of commonly methylated genes, many of the studied genes are less frequently methylated in male breast cancer, pointing towards possible differences between male and female breast carcinogenesis.

BACKGROUND: Changes in the receptor profile of primary breast cancers to their metastases (receptor conversion) have been described for the estrogen receptor α (ERα) and progesterone receptor (PR). The purpose of this study was to evaluate the impact of receptor conversion for ERα and PR on survival in a large group of distant non‐bone breast cancer metastases.METHODS: Receptor conversion was studied by immunohistochemistry in a group of 233 metastatic breast cancer patients. Kaplan‐Meier overall survival curves were plotted, and differences between the curves were analyzed by log‐rank analysis. The additional prognostic value of conversion to established prognosticators was studied by Cox regression.RESULTS: Overall survival of patients showing conversion from positive to negative ERα or PR, or from negative to positive ERα or PR, or remaining receptor negative was comparable, and significantly worse than patients remaining receptor positive. ERα or PR receptor conversion from positive in the primary breast tumor to negative in distant metastases has independent negative prognostic value.CONCLUSIONS: ERα or PR receptor conversion from positive in the primary breast cancer to negative in distant metastases has negative prognostic value. Cancer 2012. © 2012 American Cancer Society.

Introduction: When breast cancer patients develop distant metastases, the choice of systemic treatment is usually based on tissue characteristics of the primary tumor as determined by immunohistochemistry (IHC) and/or molecular analysis. Several previous studies have shown that the immunophenotype of distant breast cancer metastases may be different from that of the primary tumor (receptor conversion), leading to inappropriate choice of systemic treatment. The studies published so far are however small and/or methodologically suboptimal. Therefore, definite conclusions that may change clinical practice could not yet be drawn. We therefore aimed to study receptor conversion for estrogen receptor alpha (ERα), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) in a large group of distant (non-bone) breast cancer metastases by re-staining all primary tumors and metastases with current optimal immunohistochemical and in situ hybridization methods on full sections. Methods: A total of 233 distant breast cancer metastases from different sites (76 skin, 63 liver, 43 lung, 44 brain and 7 gastro-intestinal) were IHC stained for ERα, PR and HER2, and expression was compared to that of the primary tumor. HER2 in situ hybridization (ISH) was done in cases of IHC conversion or when primary tumors or metastases showed an IHC 2+ result. Results: Using a 10% threshold, receptor conversion by IHC for ERα, PR occurred in 10.3%, 30.0% of patients, respectively. In 10.7% of patients, conversion from ER+ or PR+ to ER-/PR- and in 3.4% from ER-/PR- to ER+ or PR+ was found. Using a 1% threshold, ERα and PR conversion rates were 15.1% and 32.6%. In 12.4% of patients conversion from ER+ or PR+ to ER-/PR-, and 8.2% from ER-/PR- to ER+ or PR+ occurred. HER2 conversion occurred in 5.2%. Of the 12 cases that showed HER2 conversion by IHC, 5 showed also conversion by ISH. One further case showed conversion by ISH, but not by IHC. Conversion was mainly from positive in the primary tumor to negative in the metastases for ERα and PR, while HER2 conversion occurred equally both ways. PR conversion occurred significantly more often in liver, brain and gastro-intestinal metastases. Conclusions: Receptor conversion by immunohistochemistry in (non-bone) distant breast cancer metastases does occur, is relatively uncommon for ERα and HER2, and is more frequent for PR, especially in brain, liver and gastro-intestinal metastases.

Diffuse large B‐cell lymphoma (DLBCL) is the most common type of adult non‐Hodgkin lymphoma and is treated with chemotherapy in combination with rituximab. Despite this aggressive therapy, the disease is fatal in 30–40% of patients. Inhibition of the apoptosis signalling pathways is strongly related to response to chemotherapy and eventual clinical outcome. In order to survive, lymphoma cells depend on disruption of the apoptosis pathway by mutations in apoptosis inducing genes or by continuous expression of anti‐apoptotic proteins. The development of molecules targeting these apoptosis inhibitors provides a very promising opportunity to specifically target tumour cells without toxicity to non‐malignant cells in DLBCL patients. Sensitivity for most of these antagonists can be predicted based on biological markers, suggesting the possibility of pre‐defining patients who will most likely benefit from these targeted therapies. Experimental therapies aimed at restoring the upstream apoptosis pathway or targeting apoptosis inhibitors are currently being tested in clinical trials and are expected to be effective particularly in chemotherapy‐refractory DLBCL, providing hope for patients who are refractory to current therapies. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Diffuse large B‐cell lymphomas (DLBCL) are highly heterogeneous with regard to clinical presentation and outcome. DLBCL copy number aberrations have been identified previously, of which the deletion at 6q21‐24 was significantly associated with a highly favorable clinical response to chemotherapy. In this study, we aimed to identify genes implicated in this and other genomic regions with recurrent losses and/or gains. To identify implicated genes, we superimposed array comparative genomic hybridization (aCGH) data onto a microarray expression dataset of 42 clinically well‐characterized primary nodal DLBCL biopsies. We confirmed that loss of 6q21‐24 is significantly associated with a highly favorable clinical response to chemotherapy. Our approach identified 316 significant genes restricted to 32 chromosomal regions, including 24 genes identified at 6q21‐24. In an independent dataset, 18% of overexpressed genes in gained regions and 55% of down‐regulated genes in deleted regions were validated. In summary, using integrative genomics novel onco and tumor suppressor genes were identified in DLBCL that were not recognized by expression profiling alone.

Clinical outcome in patients with primary nodal diffuse large B-cell lymphomas (DLBCLs) is correlated with expression of inhibitors of the intrinsic apoptosis pathway, including X-linked inhibitor of apoptosis protein (XIAP). XIAP suppresses apoptosis through inhibiting active caspase-3, caspase-7, and caspase-9. In this study, we investigated to see if the small-molecule XIAP antagonist 1396-12 induces cell death in cultured lymphoma cells of patients with DLBCL. Treatment with this XIAP antagonist resulted in relief of caspase-3 inhibition and in induction of apoptosis in 16 of 20 tested DLBCL samples. Sensitivity to the XIAP antagonist was observed in both chemotherapy-refractory and -responsive DLBCL, but did not affect peripheral blood mononuclear cells and tonsil germinal-center B cells from healthy donors. XIAP antagonist-sensitive samples were characterized by high expression levels of XIAP, relatively low expression levels of Bcl-2, and by constitutive caspase-9 activation. These data indicate that the small-molecule XIAP antagonist can induce apoptosis in cultured DLBCL cells and therefore should be considered for possible development as a therapy for these patients. In vitro sensitivity to the XIAP antagonist can be predicted based on biological markers, suggesting the possibility of predefining patients most likely to benefit from XIAP antagonist therapy.