Background Apolipoprotein D (ApoD) has been proposed as a predictor of breast cancer recurrence among estrogen receptor-positive (ER+), tamoxifen-treated patients. Methods We conducted a population-based case-control study nested in a population of 11,251 women aged 35–69 years at diagnosis with Stage I–III breast cancer between 1985 and 2001 on Denmark's Jutland Peninsula and registered with the Danish Breast Cancer Cooperative Group. We identified 541 recurrent or contralateral breast cancers cases among women with ER+ disease treated with tamoxifen for at least 1 year and 300 cases in women with ER– disease never treated with tamoxifen. We matched one control subject per case and assessed ApoD expression in the tumor cell nucleus and cytoplasm using tissue microarray immunohistochemistry. We computed the odds ratio (OR) associating ApoD expression with recurrence and adjusted for potential confounding using logistic regression. Results Cytoplasmic ApoD expression was seen in 68% of ER+ tumors, in 66% of ER– tumors, and in 66% of controls across both groups. In women with ER+ tumors, the associations of cytoplasmic ApoD expression with recurrence (OR = 1.0; 95% CI = 0.7 to 1.4) and increasing cytoplasmic expression with recurrence (OR = 1.0; 95% CI = 0.996 to 1.003) were null, as were those for women with ER– tumors. Associations for nuclear ApoD expression and combined nuclear and cytoplasmic expression were similarly near-null. Conclusion ApoD expression is likely not a predictor of recurrence in tamoxifen-treated patients. Impact This study eliminates the previously suggested marker ApoD as a predictor of recurrence among tamoxifen-treated women.

The role of cytochrome P450 drug metabolizing enzymes in the efficacy of tamoxifen treatment of breast cancer is subject to substantial interest and controversy. CYP2D6 have been intensively studied, but the role of CYP2C19 is less elucidated, and we studied the association of CYPC19 genotype and recurrence of breast cancer. We used outcome and genotyping data from the large publicly available International Tamoxifen Pharmacogenomics Consortium (ITPC) dataset. Cox regression was used to compute the hazard ratios (HRs) for recurrence. CYP2C19 genotype data was available for 2 423 patients and the final sample cohort comprised 2 102 patients. CYP2C19*2 or *19 alleles did not influence DFS. For the CYP2C19*2 allele, the HR was 1.05 (CI 0.78–1.42) and 0.79 (CI 0.32–1.94) for hetero- and homozygote carriers, respectively. The corresponding HR for hetero- and homozygote carriers of the CYP2C19*17 allele were 1.02 (CI 0.71–1.46) and 0.57 (CI 0.26–1.24), respectively. Accounting for CYP2D6 genotype status did not change these estimates. We found no evidence to support a clinically meaningful role of CYP2C19 polymorphisms and response to tamoxifen in breast cancer patients and, consequently, CYP2C19 genotype status should not be included in clinical decisions on tamoxifen treatment.

Overexpression of 14-3-3ζ has been linked to breast cancer recurrence in several studies, including studies assessing its effect on tamoxifen resistance. The study was performed to estimate the effect of 14-3-3ζ and differentiate potential prognostic or predictive utility.

Background Adjuvant tamoxifen therapy approximately halves the risk of estrogen receptor-positive (ER+) breast cancer recurrence, but many women do not respond to therapy. Observational studies nested in clinical trial populations suggest that overexpression or nuclear localization of p21-activated kinase 1 (Pak1) in primary tumors predicts tamoxifen failure. Material and methods We measured the association between Pak1 expression and breast cancer recurrence in a Danish population-based case-control study. Pak1 cytoplasmic expression level and nuclear positivity were determined by immunohistochemical staining of primary breast tumors from recurrence cases and matched controls from two breast cancer populations; women diagnosed with ER-positive tumors who received at least one year of tamoxifen therapy (ER+/TAM+), and women diagnosed with ER-negative tumors who survived for at least one year (ER-/TAM-). Pak1 staining was assessed by a single, blinded pathologist, and associations were estimated with conditional logistic regression models. Results We included 541 recurrence cases and 1:1 matched controls from the ER+/TAM + group and 300 recurrence cases and 1:1 matched controls from the ER-/TAM - group. Pak1 cytoplasmic intensity was not associated with breast cancer recurrence in either group (ER+/TAM + ORadj for strong vs. no cytoplasmic staining = 0.91, 95% CI 0.57, 1.5; ER-/TAM - ORadj for strong vs. no cytoplasmic staining = 0.74, 95% CI 0.39, 1.4). Associations between Pak1 nuclear positivity and breast cancer recurrence were similarly near null in both groups. Conclusion Pak1 positivity in primary breast tumors was neither predictive nor prognostic in this prospective, population-based study.

A 35-year-old man with a history of blunt abdominal trauma and splenic rupture was diagnosed with an ampullary adenocarcinoma. At workup, a CT scan showed multiple intra-abdominal lesions similar to peritoneal carcinosis, and the patient was referred for palliative chemotherapy. On clinical suspicion, however, a biopsy was performed on an intra-abdominal lesion, establishing the diagnosis of abdominal splenosis. A radical pancreaticoduodenectomy ad modum Whipple was performed, followed by adjuvant chemotherapy with gemcitabine. At the 18-month follow-up, the patient was free from recurrent disease. We conclude that splenosis should be considered as a differential diagnosis of peritoneal metastases in cancer patients with a history of abdominal trauma and/or splenectomy. Other reports on splenosis in cancer patients and diagnostic workup are discussed.

BACKGROUND:Cytochrome P450 2D6 (CYP2D6) inhibition reduces the concentration of 4-hydroxylated tamoxifen metabolites, but the clinical relevance remains uncertain. METHODS:We conducted a large case-control study nested in the population of 11 251 women aged 35-69 years at diagnosis of stage I-III breast cancer between 1985 and 2001 on Denmark's Jutland Peninsula and registered with the Danish Breast Cancer Cooperative Group. We identified 541 recurrent or contralateral breast cancers among women with estrogen receptor-positive (ER+) disease treated with tamoxifen for at least 1 year and 300 cancers in women with ER-negative (ER-) disease never treated with tamoxifen. We matched one control subject per case patient on ER status, menopausal status, stage, calendar time, and county, genotyped the CYP2D6*4 allele to assess genetic inhibition, and ascertained prescription history to assess drug-drug inhibition. We estimated the odds ratio (OR), associating CYP2D6 inhibition with breast cancer recurrence and adjusted for potential confounding with logistic regression. To address bias from incomplete information on CYP2D6 function, we used Monte Carlo simulation to complete a record-level probabilistic bias analysis. All statistical tests were two-sided. RESULTS:The frequency of the CYP2D6*4 minor allele was 24% in case patients with ER+ tumors, 23% in case patients with ER- tumors, and 22% each in control subjects with ER+ and ER- tumors. In women with ER+ tumors, the associations of one functional allele with recurrence (OR = 0.99; 95% confidence interval = 0.76 to 1.3) and no functional allele with recurrence (OR = 1.4; 95% confidence interval = 0.84 to 2.3) were near null, as were those for women with ER- tumors. The near-null associations persisted when evaluated by intake of medications, by combining genotype with medication history, in the probabilistic bias analysis, or by restricting the analysis to women with ER expression confirmed by re-assay. CONCLUSION:The association between CYP2D6 inhibition and recurrence in tamoxifen-treated patients is likely null or small.

Abstract Abstract 5202 We here report the observation of the development of a splenic marginal zone lymphoma (SMZL) after years of active chronic visceral Leishmania (VL) infection, implying a possible pathogenic link between these two conditions, where the neoplastic process is preceded by a prolonged period of chronic antigen stimulation. In 2004, a 60-year old male developed attack-like episodes of septic fever with chills, rigor and subsequent profound fatigue. He had a 4 years previous medical history of severe asthma-like symptoms and hypereosinophilia. A bone marrow (BM) and liver biopsy were inconclusive. A whole-body computed tomography showed a moderately enlarged spleen. No evidence of bacterial, fungal or viral infection was found; the symptoms persisted, although mitigated, with occasional exacerbations over the following 3 years. By 2007 the patient was admitted again and a new BM biopsy was taken, still showing reactive changes. Due to increased splenomegaly, a diagnostic splenectomy was performed. Examination of the spleen revealed a primary splenic marginal zone lymphoma (SMZL). In 2010 the patient was admitted with septicaemia and constitutional symptoms. A BM biopsy showed the presence of numerous Leishmania amastigotes and a retrospective review of all previous biopsies (since 2004) identified Leishmania amastigotes in all of them. In fact, a thorough travel history covering the previous two decades revealed several visits, often twice a year, to the Mediterranean basin, e.g. Greece and Malta, areas endemic for Leishmania infantum (L. infantum). Visceral Leishmaniasis is a frequent opportunistic infection in HIV-infected immunodeficient individuals but uncommon in cancer patients, and only a few cases of VL in patients with already well-established malignant lymphoma have been reported. Chronic antigenic stimulation by microbial pathogens has been proposed as a pathogenetic factor in a variety of marginal zone lymphomas. Tissue specific immune responses toward Leishmania parasites have been shown in rodents, and the spleen is a ‘safe harbor’ for the long-term persistence of visceralizing Leishmania. Sustained antigenic stimulation with upregulation of critical signaling pathways may result in prolonged polyclonal B-cell proliferation, and a subsequent increased risk of malignant transformation. This case is the first to provide evidence for a possible link between chronic antigen stimulation by long-lasting L. infantum infection and the development of a SMZL. Disclosures: No relevant conflicts of interest to declare.

BACKGROUND:Estrogen receptor (ER) expression predicts tamoxifen response, which halves the risk of breast cancer recurrence. We examined clinical factors associated with concordance between ER expression at diagnosis and centralized re-assay, and the association of concordance with breast cancer recurrence. MATERIAL AND METHODS:We used immunohistochemistry to assess ER expression on archived fixed, paraffin-embedded breast carcinoma tissue excised from women aged 35-69 years, diagnosed 1985-2001 in Jutland, Denmark. We calculated the percentage agreement, positive predictive value (PPV) and negative predictive value (NPV) of ER status at diagnosis and re-assay. We used logistic regression to investigate factors associated with concordance, and its association with recurrence (odds ratios (OR) and associated 95% confidence intervals (95%CI)). RESULTS:ER was re-assayed in 91% of patients (n = 1530). Concordance was better in ER + than ER- tumors (PPV = 94% vs. NPV = 75%). Factors associated with concordance included menopausal status, tumor size, surgical procedure, diagnostic period, lymph node status and time to recurrence. ER + women at diagnosis who re-assayed ER + were less likely to have recurrent disease (OR = 0.49, 95% CI = 0.28, 0.86) than those who re-assayed ER-. In originally ER- women, concordance was not associated with recurrence (OR = 0.97, 95% CI = 0.66, 1.42). CONCLUSIONS:Several clinical factors were associated with ER assay concordance. Some women were ineffectively treated with tamoxifen, or required but did not receive tamoxifen. We observed almost exactly the protective effect of endocrine therapy among tamoxifen-treated ER + women whose tumors expressed the ER on re-assay, compared with those ER- on re-assay. Diagnostic pathology results for ER + tumors appear a valid and useful resource for research studies. However, those for ER- tumors have lower validity. Study-specific considerations regarding the aims, diagnostic period, and consequences of including ER- patients with truly ER + disease ought to be examined when using diagnostic pathology results for ER- tumors in research studies.