Andreas D. Hartkopf

Early dissemination seeds metastasis in breast cancer

Accumulating data suggest that metastatic dissemination often occurs early during tumour formation, but the mechanisms of early metastatic spread have not yet been addressed. Here, by studying metastasis in a HER2-driven mouse breast cancer model, we show that progesterone-induced signalling triggers migration of cancer cells from early lesions shortly after HER2 activation, but promotes proliferation in advanced primary tumour cells. The switch from migration to proliferation was regulated by increased HER2 expression and tumour-cell density involving microRNA-mediated progesterone receptor downregulation, and was reversible. Cells from early, low-density lesions displayed more stemness features, migrated more and founded more metastases than cells from dense, advanced tumours. Notably, we found that at least 80% of metastases were derived from early disseminated cancer cells. Karyotypic and phenotypic analysis of human disseminated cancer cells and primary tumours corroborated the relevance of these findings for human metastatic dissemination.

Measurement of tumour size with mammography, sonography and magnetic resonance imaging as compared to histological tumour size in primary breast cancer

BackgroundTumour size in breast cancer influences therapeutic decisions. The purpose of this study was to evaluate sizing of primary breast cancer using mammography, sonography and magnetic resonance imaging (MRI) and thereby establish which imaging method most accurately corresponds with the size of the histological result.MethodsData from 121 patients with primary breast cancer were analysed in a retrospective study. The results were divided into the groups “ductal carcinoma in situ (DCIS)”, invasive ductal carcinoma (IDC) + ductal carcinoma in situ (DCIS)”, “invasive ductal carcinoma (IDC)”, “invasive lobular carcinoma (ILC)” and “other tumours” (tubular, medullary, mucinous and papillary breast cancer). The largest tumour diameter was chosen as the sizing reference in each case. Bland-Altman analysis was used to determine to what extent the imaging tumour size correlated with the histopathological tumour sizes.ResultsTumour size was found to be significantly underestimated with sonography, especially for the tumour groups IDC + DCIS, IDC and ILC. The greatest difference between sonographic sizing and actual histological tumour size was found with invasive lobular breast cancer. There was no significant difference between mammographic and histological sizing. MRI overestimated non-significantly the tumour size and is superior to the other imaging techniques in sizing of IDC + DCIS and ILC.ConclusionsThe histological subtype should be included in imaging interpretation for planning surgery in order to estimate the histological tumour size as accurately as possible.

Prognostic relevance of disseminated tumour cells from the bone marrow of early stage breast cancer patients – Results from a large single-centre analysis

BACKGROUND This is the largest single-centre study to determine the prognostic relevance of disseminated tumour cells (DTCs) from the bone marrow (BM) of stage I-III breast cancer patients. Additionally, we aimed to analyse the impact of DTC detection on adjuvant bisphosphonate (BP) treatment efficacy. METHODS BM aspirates were collected during primary surgery for early breast cancer (EBC; T1-4, N0-2, M0) at Tuebingen University, Germany, between January 2001 and January 2013. DTCs were identified by immunocytochemistry (pancytokeratin antibody A45/B-B3) and cytomorphology. We retrospectively estimated the influence of DTC detection and BP treatment on disease-free survival (DFS) and overall survival (OS) using univariate (log-rank test) and multivariate (cox regression) analysis. FINDINGS BM aspirates were available from 3141 patients. In 803 (26%) of these, DTCs were detectable. As compared to DTC-negative patients, DTC-positive patients more frequently had larger tumors (p<0.001), lymph node involvement (p<0.001), hormonal receptor positive tumours (p<0.001) and HER2-positive tumours (p=0.048). DTC-positive patients were at an increased risk of relapse (hazard ratio (HR) 1.74, 95% confidence interval (CI) 1.34-2.25, p<0.001) and death (HR 1.44 95% CI 1.13-1.86, p=0.004). In the multivariate analysis DTCs were an independent predictor of DSF and OS. Additionally, BP treatment had no significant influence on DFS or OS in DTC-negative patients, while it was significantly associated with increased DFS (p<0.001) and OS (p=0.006) in DTC-positive patients. INTERPRETATION These data confirm the clinical validity of DTCs from the BM for prognostication of early breast cancer patients. Further studies are warranted to determine whether DTCs are predictive for adjuvant treatment efficacy using bisphosphonates.

Therapeutic intervention based on circulating tumor cell phenotype in metastatic breast cancer: concept of the DETECT study program

AbstractPurpose The aim of the ongoing DETECT study program is to evaluate therapeutic intervention based on phenotypes of circulating tumor cells (CTC) in patients with metastatic breast cancer (MBC). Currently (as of July 2015) more than half of the projected about 2000 patients with MBC have already been screened for CTC.MethodsWomen with HER2-negative primary tumor and presence of CTC are recruited into different DETECT trials according to the HER2-phenotype of CTC. Patients with HER2-positive CTC are randomized to treatment with physicians’ choice therapy (standard chemo- or endocrine therapy) with or without additional HER2-targeted therapy with lapatinib in the DETECT III trial. In DETECT IVa, postmenopausal patients with hormone-receptor positive primary cancer and HER2-negative CTC receive everolimus and standard endocrine therapy. For women with HER2-negative CTC and triple negative MBC or hormone-receptor positive tumor and indication for chemotherapy, a treatment with eribulin is offered (DETECT IVb). The clinical efficacy is investigated by CTC-Clearance and progression-free survival (PFS). The DETECT V/CHEVENDO trial extends the DETECT study program for women with HER2-positive and hormone-receptor positive MBC. The primary objective of this trial is to compare safety and quality of life (QoL) as assessed by the occurrence of adverse events in patients treated with dual (trastuzumab plus pertuzumab) HER2-targeted therapy plus either endocrine or chemotherapy. The translational research projects of the DETECT study program focus on further molecular characterization of CTC and evaluation of markers for their suitability to predict treatment response and to facilitate the development of more personalized treatment options.

Pooled analysis of the prognostic relevance of progesterone receptor status in five German cohort studies

The progesterone receptor (PR) has been increasingly well described as an important mediator of the pathogenesis and progression of breast cancer. The aim of this study was to assess the role of PR status as a prognostic factor in addition to other well-established prognostic factors. Data from five independent German breast cancer centers were pooled. A total of 7,965 breast cancer patients were included for whom information about their PR status was known, as well as other patient and tumor characteristics commonly used as prognostic factors. Cox proportional hazards models were built to compare the predictive value of PR status in addition to age at diagnosis, tumor size, nodal status, grading, and estrogen receptor (ER) status. PR status significantly increased the accuracy of prognostic predictions with regard to overall survival, distant disease-free survival, and local recurrence-free survival. There were differences with regard to its prognostic value relative to subgroups such as nodal status, ER status, and grading. The prognostic value of PR status was greatest in patients with a positive nodal status, negative ER status, and low grading. The PR-status adds prognostic value in addition to ER status and should not be omitted from clinical routine testing. The significantly greater prognostic value in node-positive and high-grade tumors suggests a greater role in the progression of advanced and aggressive tumors.

Dose-Response Association of CD8+ Tumor-Infiltrating Lymphocytes and Survival Time in High-Grade Serous Ovarian Cancer.

Importance Cytotoxic CD8+ tumor-infiltrating lymphocytes (TILs) participate in immune control of epithelial ovarian cancer; however, little is known about prognostic patterns of CD8+ TILs by histotype and in relation to other clinical factors. Objective To define the prognostic role of CD8+ TILs in epithelial ovarian cancer. Design, Setting, and Participants This was a multicenter observational, prospective survival cohort study of the Ovarian Tumor Tissue Analysis Consortium. More than 5500 patients, including 3196 with high-grade serous ovarian carcinomas (HGSOCs), were followed prospectively for over 24 650 person-years. Exposures Following immunohistochemical analysis, CD8+ TILs were identified within the epithelial components of tumor islets. Patients were grouped based on the estimated number of CD8+ TILs per high-powered field: negative (none), low (1-2), moderate (3-19), and high (≥20). CD8+ TILs in a subset of patients were also assessed in a quantitative, uncategorized manner, and the functional form of associations with survival was assessed using penalized B-splines. Main Outcomes and Measures Overall survival time. Results The final sample included 5577 women; mean age at diagnosis was 58.4 years (median, 58.2 years). Among the 5 major invasive histotypes, HGSOCs showed the most infiltration. CD8+ TILs in HGSOCs were significantly associated with longer overall survival; median survival was 2.8 years for patients with no CD8+ TILs and 3.0 years, 3.8 years, and 5.1 years for patients with low, moderate, or high levels of CD8+ TILs, respectively (P value for trend = 4.2 × 10−16). A survival benefit was also observed among women with endometrioid and mucinous carcinomas, but not for those with the other histotypes. Among HGSOCs, CD8+ TILs were favorable regardless of extent of residual disease following cytoreduction, known standard treatment, and germline BRCA1 pathogenic mutation, but were not prognostic for BRCA2 mutation carriers. Evaluation of uncategorized CD8+ TIL counts showed a near-log-linear functional form. Conclusions and Relevance This study demonstrates the histotype-specific nature of immune infiltration and provides definitive evidence for a dose-response relationship between CD8+ TILs and HGSOC survival. That the extent of infiltration is prognostic, not merely its presence or absence, suggests that understanding factors that drive infiltration will be the key to unraveling outcome heterogeneity in this cancer.

Circulating tumor cells in breast cancer

Detection of disseminated tumor cells (DTCs) in bone marrow and of circulating tumor cells (CTCs) in the blood has become a major focus of translational cancer research. DTC presence is a common phenomenon seen in 30-40% of primary breast cancer patients and is strongly associated with poor clinical outcome. Since bone marrow biopsy is an invasive procedure, evaluation of CTCs might become a desired alternative. Recent clinical trials have shown CTC detection to be a promising prognostic tool in both primary and metastatic setting. Evaluation of CTCs might be useful for therapy monitoring and their characterization might help to identify novel targets for biological therapies aimed at disrupting earliest steps of metastatic cascade.

Dormancy in breast cancer

Tumor dormancy describes a prolonged quiescent state in which tumor cells are present, but disease progression is not yet clinically apparent. Breast cancer is especially known for long asymptomatic periods, up to 25 years, with no evidence of the disease, followed by a relapse. Factors that determine the cells decision to enter a dormant state and that control its duration remain unclear. In recent years, considerable progress has been made in understanding how tumor cells circulating in the blood interact and extravasate into secondary sites and which factors might determine whether these cells survive, remain dormant, or become macrometastases. The mechanisms of tumor cell dormancy are still not clear. Two different hypotheses are currently discussed: tumor cells persist either by completely withdrawing from the cell cycle or by continuing to proliferate at a slow rate that is counterbalanced by cell death. Because dormant disseminated tumor cells may be the founders of metastasis, one hypothesis is that dormant tumor cells, or at least a fraction of them, share stem cell-like characteristics that may be responsible for their long half-lives and their suggested resistance to standard chemotherapy. Therefore, knowledge of the biology of tumor cell dormancy may be the basis from which to develop innovative targeted therapies to control or eliminate this tumor cell fraction. In this review, we discuss biological mechanisms and clinical implications of tumor dormancy in breast cancer patients.

Pooled Analysis of the Prognostic Relevance of Disseminated Tumor Cells in the Bone Marrow of Patients With Ovarian Cancer

Objective Detection of disseminated tumor cells (DTCs) in the bone marrow (BM) of patients with breast cancer is associated with poor outcomes. Recent studies demonstrated that DTCs may serve as a prognostic factor in ovarian cancer. The aim of this 3-center study was to evaluate the impact of BM status on survival in a large cohort of patients with ovarian cancer. Materials and Methods Four hundred ninety-five patients with primary ovarian cancer were included in this 3-center prospective study. Bone marrow aspirates were collected intraoperatively from the iliac crest. Disseminated tumor cells were identified by antibody staining and by cytomorphology. Clinical outcome was correlated with the presence of DTCs. Results Disseminated tumor cells were detected in 27% of all BM aspirates. The number of cytokeratin-positive cells ranged from 1 to 42 per 2 × 106 mononuclear cells. Disseminated tumor cell status did correlate with histologic subtype but not with any of the other established clinicopathologic factors. The overall survival was significantly shorter among DTC-positive patients compared to DTC-negative patients (51 months; 95% confidence interval, 37–65 months vs 33 months; 95% confidence interval, 23–43 months; P = 0.023). In the multivariate analysis, BM status, International Federation of Gynecology and Obstetrics stage, nodal status, resection status, and age were independent predictors of reduced overall survival, whereas only BM status, International Federation of Gynecology and Obstetrics stage, and resection status independently predicted progression-free survival. Conclusions Tumor cell dissemination into the BM is a common phenomenon in ovarian cancer. Disseminated tumor cell detection has the potential to become an important biomarker for prognostication and disease monitoring in patients with ovarian cancer.

The presence and prognostic impact of apoptotic and nonapoptotic disseminated tumor cells in the bone marrow of primary breast cancer patients after neoadjuvant chemotherapy

IntroductionNeoadjuvant systemic therapy of primary breast cancer (PBC) patients offers the possibility to monitor treatment response. However, patients might have metastatic relapse despite achieving a pathologic complete response (pCR). This indicates that local response to therapy must not be representative for systemic treatment efficacy. Therefore, the aim of this study was to compare local response with systemic tumor cell dissemination by determining the presence of disseminated tumor cells (DTCs), including apoptotic tumor cells, in the bone marrow (BM) of PBC patients after neoadjuvant chemotherapy (NACT).MethodsDTCs were detected by immunocytochemistry (pancytokeratin antibody A45-B/B3) and cytomorphology (DTC status). The presence of apoptotic tumor cells was determined by using the M30 antibody (M30 status). This antibody detects a neo-epitope that is expressed only during early apoptosis.ResultsBM aspirates from 400 PBC patients that had completed NACT were eligible for this study. Of these, 167 (42%) patients were DTC positive (DTC status). The M30 status was investigated in 308 patients. Apoptotic (M30-positive) tumor cells were detected in 89 (29%) of these. Whereas the DTC status was not correlated (P = 0.557) to local treatment response (that is, pCR or a clinical complete/partial response), the presence of M30-positive tumor cells was significantly higher in patients that responded to therapy (P = 0.026). Additionally, DTC-positive patients were at an increased risk for disease relapse (hazard ratio, 1.87; 95% CI, 1.11 to 3.15; P = 0.019).ConclusionThe presence of DTC is independent of therapy response of the primary tumor. As patients that are DTC positive after NACT have an unfavorable outcome, they might benefit from additional systemic treatment.