Prognostic value of disseminated tumor cells in unresectable pancreatic ductal adenocarcinoma: a prospective observational study.

BACKGROUND: Although pancreatic ductal adenocarcinoma (PDAC) rarely metastasizes to the skeleton, disseminated tumor cells have been detected in bone marrow samples from patients with this disease. The prognostic value of such findings is currently unclear. Thus, the current study aimed to clarify the prognostic information associated with disseminated tumor cell detection in samples from patients with PDAC. METHODS: Bone marrow aspirates were obtained from 48 patients with locally advanced (n = 11) or metastatic (n = 37) PDAC, before and after 2 months of chemotherapy. Disseminated tumor cells were detected with an mRNA panel and quantitative reverse transcription PCR. We used the highest levels measured in healthy bone marrow (n = 30) as a threshold to define the positive detection of disseminated tumor cells. Progression-free and overall survival were analyzed with Kaplan-Meier and Cox proportional hazards regression analyses. RESULTS: Disseminated tumor cells were detected in 15/48 (31%) bone marrow samples obtained before starting chemotherapy and in 8/25 (32%) samples obtained during chemotherapy. Patients with disseminated tumor cells detected before therapy had significantly shorter progression-free (p = 0.03; HR = 2.0) and overall survival (p = 0.03; HR = 2.0), compared to those without disseminated tumor cells in the bone marrow. When restricting disseminated tumor cell detection to keratins KRT7 and KRT8, the prognostic information was substantially stronger (p = 1 × 10-6; HR = 22, and p = 2 × 10-5; HR = 7.7, respectively). The multivariable Cox regression analysis demonstrated that disseminated tumor cell detection prior to treatment had independent prognostic value. In contrast, disseminated tumor cells detected during treatment did not have prognostic value. CONCLUSIONS: Disseminated tumor cells detected before commencing chemotherapy had prognostic value in patients with inoperable PDAC.

Fragment size and level of cell-free DNA provide prognostic information in patients with advanced pancreatic cancer.

BACKGROUND: It was recently demonstrated that the size of cell-free DNA (cfDNA) fragments that originates from tumor cells are shorter than cfDNA fragments that originates from non-malignant cells. We investigated whether cfDNA fragment size and cfDNA levels might have prognostic value in patients with advanced pancreatic cancer. METHODS: Blood samples were obtained from patients with advanced pancreatic cancer, before (n = 61) initiation of chemotherapy and after the first cycle of chemotherapy (n = 39). Samples were separated with density centrifugation and plasma DNA was isolated. Mode cfDNA fragment size and cfDNA levels were then determined using a 2100 Bioanalyzer. A cohort of partially age-matched healthy volunteers (n = 28) constituted the control group. RESULTS: Both a pre-treatment cfDNA fragment size of ≤ 167 bp (mode) and high pre-treatment cfDNA levels were associated with shorter progression-free survival (PFS) (p = 0.002 and p < 0.001, respectively) and overall survival (OS) (p = 0.001 and p = 0.001, respectively). Furthermore, multivariable Cox regression analyses demonstrated that pre-treatment cfDNA levels could independently predict prognosis for both PFS (HR = 3.049, p = 0.005) and OS (HR = 2.236, p = 0.028). CONCLUSION: This study demonstrates that cfDNA fragment size and cfDNA levels can be used to predict disease outcome in patients with advanced pancreatic cancer. The described approach, using a rapid, economic and simple test to reveal prognostic information, has potential for future treatment stratification and monitoring.

Expression profiling and intracellular localization studies of the novel Proline-, Histidine-, and Glycine-rich protein 1 suggest an essential role in gastro-intestinal epithelium and a potential clinical application in colorectal cancer diagnostics.

BACKGROUND: The primary function of the intestines is the absorption of water and nutrients. Although our knowledge about these processes on the cellular level is extensive, a number of important intracellular elements remain unknown. Here, we characterize the novel proline-, histidine-, glycine-rich 1 (PHGR1) mRNA and protein on the molecular level and propose a functional role of the PHGR1 protein in the intestinal and gastric epithelium. METHODS: PHGR1 mRNA and protein expression in human tissues and cell lines were characterized by quantitative RT-PCR, in situ hybridization, Northern blotting, Western blotting, and immunohistochemistry. Glycosylation was assessed by a chemical deglycosylation assay, whereas intracellular localization was studied by immunofluorescent staining of cell line cells. PHGR1 mRNA levels in HT29 cells was reduced by RNA interference and the resulting global changes in gene expression assessed by microarray hybridization. RESULTS: PHGR1 mRNA and protein were found to be expressed specifically in epithelial cells of intestinal mucosa, with the highest expression in the most mature and differentiated cells. PHGR1 protein was found to be glycosylated and to localize to both the cytoplasm and nucleus. Transcript profiling and gene ontology analysis of HT29 cells subjected to PHGR1 knockdown suggested a functional relationship with transport and metabolic processes. Examination of PHGR1 mRNA and protein levels in lymph nodes with known colorectal cancer metastases indicated that they may serve as biomarkers for detection of such metastases. CONCLUSIONS: Functional analyses of the novel PHGR1 mRNA and protein suggest an essential role in gastrointestinal epithelium and a clinical application in detection of colorectal cancer lymph node metastases.

Single-cell mRNA profiling reveals transcriptional heterogeneity among pancreatic circulating tumour cells.

BACKGROUND: Single-cell mRNA profiling of circulating tumour cells may contribute to a better understanding of the biology of these cells and their role in the metastatic process. In addition, such analyses may reveal new knowledge about the mechanisms underlying chemotherapy resistance and tumour progression in patients with cancer. METHODS: Single circulating tumour cells were isolated from patients with locally advanced or metastatic pancreatic cancer with immuno-magnetic depletion and immuno-fluorescence microscopy. mRNA expression was analysed with single-cell multiplex RT-qPCR. Hierarchical clustering and principal component analysis were performed to identify expression patterns. RESULTS: Circulating tumour cells were detected in 33 of 56 (59%) examined blood samples. Single-cell mRNA profiling of intact isolated circulating tumour cells revealed both epithelial-like and mesenchymal-like subpopulations, which were distinct from leucocytes. The profiled circulating tumour cells also expressed elevated levels of stem cell markers, and the extracellular matrix protein, SPARC. The expression of SPARC might correspond to an epithelial-mesenchymal transition in pancreatic circulating tumour cells. CONCLUSION: The analysis of single pancreatic circulating tumour cells identified distinct subpopulations and revealed elevated expression of transcripts relevant to the dissemination of circulating tumour cells to distant organ sites.

Neoadjuvant chemotherapy versus surgery first for resectable pancreatic cancer (Norwegian Pancreatic Cancer Trial - 1 (NorPACT-1)) - study protocol for a national multicentre randomized controlled trial.

BACKGROUND: Pancreatic cancer is the fourth leading cause of cancer-related death. While surgical resection remains the foundation for potentially curative treatment, survival benefit is achieved with adjuvant oncological treatment. Thus, completion of multimodality treatment (surgical resection and (neo)adjuvant chemotherapy) to all patients and early treatment of micrometastatic disease is the ideal goal. NorPACT-1 aims to test the hypothesis that overall mortality at one year after allocation of treatment can be reduced with neoadjuvant chemotherapy in surgically treated patients with resectable pancreatic cancer. METHODS/DESIGN: The NorPACT- 1 is a multicentre, randomized controlled phase III trial organized by the Norwegian Gastrointestinal Cancer Group for Hepato-Pancreato-Biliary cancer. Patients with resectable adenocarcinoma of the pancreatic head are randomized to receive either surgery first (Group 1: SF/control) or neoadjuvant chemotherapy (Group 2: NT/intervention) with four cycles FOLFIRINOX followed by resection. Both groups receive adjuvant chemotherapy with gemicitabine and capecitabine (six cycles in Group 1, four cycles in Group 2). In total 90 patients will be randomized in all the five Norwegian university hospitals performing pancreatic surgery. Primary endpoint is overall mortality at one year following commencement of treatment for those who ultimately undergo resection. Secondary endpoints are overall survival after date of randomization (intention to treat), overall survival after resection, disease-free survival, histopathological response, complication rates after surgery, feasibility of neoadjuvant and adjuvant chemotherapy, completion rates of all parts of multimodal treatment, and quality-of-life. Bolt-on to the study is a translational research program that aims at identifying factors that are predictive of response to NT, the risk of distant cancer spread, and patient outcome. DISCUSSION: NorPACT- 1 is designed to investigate the additional benefit of NT compared to standard treatment only (surgery + adjuvant chemotherapy) for resectable cancer of the pancreatic head to decrease early mortality (within one year) in resected patients. TRIAL REGISTRATION: Trial open for accrual 01.02.2017. ClinicalTrials.gov Identifier: NCT02919787 . Date of registration: September 14, 2016.

Circulating tumor cells in pancreatic cancer patients: methods of detection and clinical implications.

The poor prognosis of pancreatic cancer patients is associated with the frequent and early dissemination of the disease, as well as late detection due to unspecific and late symptoms from the primary tumor. Pancreatic cancers frequently spread to the liver, lung and skeletal system, suggesting that pancreatic tumor cells must be able to intravasate and travel through the circulation to distant organs. Circulating tumor cells (CTCs) are tumor cells that have acquired the ability to enter the circulatory system; this cell population is ultimately responsible for the development of metastases in distant organs. Clinical studies have revealed that the presence of CTCs in blood is correlated with disease progression for other cancers, such as breast, colorectal and prostate cancer. However, as CTCs are extremely rare, both enrichment and sensitive methods of detection are required for their enumeration. This review highlights various enrichment procedures and methods for the detection of CTCs. Furthermore, we systematically review previously reported studies of the clinical relevance of CTC detection in pancreatic cancer patients. There is evidence that the presence of CTCs also correlates with an unfavorable outcome in pancreatic cancer patients. However, technical/methodological issues may explain why some studies only show a trend toward an association between CTC detection and disease progression. Larger studies, as well as characterization of the CTC population, are required to achieve further insight into the clinical implications of CTC detection in pancreatic cancer patients.

Comparison of molecular and immunocytochemical methods for detection of disseminated tumor cells in bone marrow from early breast cancer patients.

BACKGROUND: Disseminated tumor cells (DTCs) have potential to predict the effect of adjuvant treatment. The purpose of this study was to compare two methods, reverse transcription quantitative PCR (RT-qPCR) and immunocytochemisty (ICC), for detecting breast cancer DTCs in bone marrow (BM) from early breast cancer patients. METHODS: We investigated a subset (n = 313) of BM samples obtained from 271 early breast cancer patients in the "Secondary Adjuvant Taxotere Treatment" (SATT)-trial. All patients in this study had node positive or intermediate/high-risk node negative non-metastatic disease. The DTCs were detected by ICC using AE1-AE3 anti-cytokeratin monoclonal antibodies. Patients with DTCs detected in their BM by ICC after standard adjuvant fluorouracil, cyclophosphamide, epirubicin (FEC) chemotherapy were offered docetaxel treatment. For comparison, 5 × 106 mononuclear cells from the aliquoted BM samples were also analyzed by RT-qPCR using a multimarker (MM) assay based on the tumor cell mRNA markers keratin 19 (KRT19), mammaglobin A (hMAM), and TWIST1. In the MM-assay, a sample was defined as positive for DTCs if at least one of the mRNA markers was positive. RESULTS: The MM RT-qPCR assay identified DTCs in 124 (40%) of the 313 BM samples compared with 23/313 (7%) of the samples analyzed by ICC. The concordance between the MM RT-qPCR and ICC was 61% (Kappa value = 0.04) and twelve of the BM samples were positive by both methods. By RT-qPCR, 46/313 (15%) samples were positive for KRT19, 97/313 (31%) for TWIST1, and 3/313 (1%) for hMAM mRNA. There were no statistically significant associations between the individual mRNA markers. CONCLUSION: The RT-qPCR based method demonstrated more DTC-positive samples than ICC. The relatively low concordance of positive DTC-status between the two different assessment methods suggests that they may be complementary. The clinical relevance of the methods will be evaluated based on future clinical outcome data. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00248703.

Fatigue and weight loss predict survival on circadian chemotherapy for metastatic colorectal cancer.

BACKGROUND: Chemotherapy-induced neutropenia has been associated with prolonged survival selectively in patients on a conventional schedule (combined 5-fluorouracil, leucovorin, and oxaliplatin [FOLFOX2]) but not on a chronomodulated schedule of the same drugs administered at specific circadian times (chronoFLO4). The authors hypothesized that the early occurrence of chemotherapy-induced symptoms correlated with circadian disruption would selectively hinder the efficacy of chronotherapy. METHODS: Fatigue and weight loss (FWL) were considered to be associated with circadian disruption based on previous data. Patients with metastatic colorectal cancer (n = 543) from an international phase 3 trial comparing FOLFOX2 with chronoFLO4 were categorized into 4 subgroups according to the occurrence of FWL or other clinically relevant toxicities during the initial 2 courses of chemotherapy. Multivariate Cox models were used to assess the role of toxicity on the time to progression (TTP) and overall survival (OS). RESULTS: The proportions of patients in the 4 subgroups were comparable in both treatment arms (P = .77). No toxicity was associated with TTP or OS on FOLFOX2. The median OS on FOLFOX2 ranged from 16.4 (95% confidence limits [CL], 7.2-25.6 months) to 19.8 months (95% CL, 17.7-22.0 months) according to toxicity subgroup (P = .45). Conversely, FWL, but no other toxicity, independently predicted for significantly shorter TTP (P < .0001) and OS (P = .001) on chronoFLO4. The median OS on chronoFLO4 was 13.8 months (95% CL, 10.4-17.2 months) or 21.1 months (95% CL, 19.0-23.1 months) according to presence or absence of chemotherapy-induced FWL, respectively. CONCLUSIONS: Early onset chemotherapy-induced FWL was an independent predictor of poor TTP and OS only on chronotherapy. Dynamic monitoring to detect early chemotherapy-induced circadian disruption could allow the optimization of rapid chronotherapy and concomitant improvements in safety and efficacy.

Influence of microsatellite instability and KRAS and BRAF mutations on lymph node harvest in stage I-III colon cancers.

Lymph node (LN) harvest is influenced by several factors, including tumor genetics. Microsatellite instability (MSI) is associated with improved node harvest, but the association to other genetic factors is largely unknown. Research methods included a prospective series of stage I-III colon cancer patients undergoing ex vivo sentinel-node sampling. The presence of MSI, KRAS mutations in codons 12 and 13, and BRAF V600E mutations was analyzed. Uni- and multivariate regression models for node sampling were adjusted for clinical, pathological and molecular features. Of 204 patients, 67% had an adequate harvest (≥ 12 nodes). Adequate harvest was highest in patients whose tumors exhibited MSI (79%; odds ratio [OR] 2.5, 95% confidence interval [CI] 1.2-4.9; P = 0.007) or were located in the proximal colon (73%; 2.8, 1.5-5.3; P = 0.002). In multiple linear regression, MSI was a significant predictor of the total LN count (P = 0.02). Total node count was highest for cancers with MSI and no KRAS/BRAF mutations. The independent association between MSI and a high LN count persisted for stage I and II cancers (P = 0.04). Tumor location in the proximal colon was the only significant predictor of an adequate LN harvest (adjusted OR 2.4, 95% CI 1.2-4.9; P = 0.01). An increase in the total number of nodes harvested was not associated with an increase in nodal metastasis. In conclusion, number of nodes harvested is highest for cancers of the proximal colon and with MSI. The nodal harvest associated with MSI is influenced by BRAF and KRAS genotypes, even for cancers of proximal location. Mechanisms behind the molecular diversity and node yield should be further explored.

Prognostic comparison of the proliferation markers (mitotic activity index, phosphohistone H3, Ki67), steroid receptors, HER2, high molecular weight cytokeratins and classical prognostic factors in T1₋2N0M0 breast cancer.

The proliferation factors: mitotic activity index (MAI), phosphohistone H3 (PPH3) and Ki67 have strong prognostic value in early breast cancer but their independent value to each other and other prognostic factors has not been evaluated. In 237 T1₋2N0M0 breast cancers without systemic adjuvant treatment, formalized MAI assessment and strictly standardized, fully automated quantitative immunohistochemistry (IHC) for Ki67, PPH3, estrogen (ER) and progesterone receptor (PR), HER2, cytokeratins-5/6 and -14, and automated digital image analysis (DIA) for measuring PPH3 and Ki67 were performed. Section thickness was measured to further control IHC measurements. All features were measured in the periphery of tumors. The different proliferation assessments and other well-established clinicopathological and biomarker prognostic factors were compared. DIA-Ki67 added prognostically to PPH3. None of the other biomarkers or clinicopathological variables added prognostically to this PPH3/Ki67 combination. However, when PPH3 is replaced by MAI the prognostic value is nearly the same. In early operable node negative breast cancer without adjuvant systemic treatment, Ki67 with a threshold of 6.5% assessed by digital image analysis in the periphery of the tumor is prognostically strong. The combination of either PPH3/Ki67 or MAI/Ki67 overshadowed the prognostic value of all other features including Ki67 alone.

The prognostic value of MARCKS-like 1 in lymph node-negative breast cancer.

There is a need for new biomarkers to more correctly identify node-negative breast cancer patients with a good or bad prognosis. Myristoylated alanine-rich C kinase substrate like-1 (MARCKSL1) is a membrane-bound protein that is associated with cell spreading, integrin activation and exocytosis. Three hundred and five operable T(1,2)N(0)M(0) lymph node-negative breast cancer patients (median follow-up time 121 months, range 10-178 months) were evaluated for MARCKSL1 expression by immunohistochemistry and quantitative real-time PCR. The results were compared with classical prognosticators (age, tumor diameter, grade, estrogen receptor, and proliferation), using single (Kaplan-Meier) and multivariate survival analysis (Cox model). Forty-seven patients (15 %) developed distant metastases. With single and multivariate analysis of all features, MARCKSL1 protein expression was the strongest prognosticator (P < 0.001, HR = 5.1, 95 % CI = 2.7-9.8). Patients with high MARCKSL1 expression (n = 23) showed a 44 % survival versus 88 % in patients with low expression at 15-year follow-up. mRNA expression of MARCKSL1 in formalin fixed paraffin-embedded tissue was also prognostic (P = 0.002, HR = 3.6, 95 % CI = 1.5-8.3). However, the prognostic effect of high and low was opposite from the protein expression, i.e., low expression (relative expression ≤ 0.0264, n = 76) showed a 79 % survival versus 92 % in those with high expression of MARCKSL1 mRNA. Multivariate analysis of all features with distant metastases free survival as the end-point showed that the combination of MARCKSL1 protein and phosphohistone H3 (PPH3) has the strongest independent prognostic value. Patients with high expression (≥13) of PPH3 and high MARCKSL1 protein had 45 % survival versus 78 % survival for patients with low MARCKSL1 protein expression and high expression (≥13) of PPH3. In conclusion, MARCKSL1 has strong prognostic value in lymph node-negative breast cancer patients, especially in those with high proliferation.

Prognostic relevance of occult metastases detected by cytokeratin 20 and mucin 2 mRNA levels in sentinel lymph nodes from colon cancer patients.

PURPOSE: To investigate the prognostic value of occult metastases detected by quantitative measurements of candidate biomarkers in sentinel lymph nodes (SLNs) from patients curatively resected for colon cancer. METHODS: Resection specimens from consecutive patients undergoing surgery for localized colon cancer were subjected to ex vivo SLN mapping. SLNs were examined for the presence of metastases by routine hematoxylin-erythrosin-safranin staining and by cytokeratin 20 (CK20) and mucin 2 (MUC2) mRNA quantification. The patients were stratified according to KRAS and BRAF mutation status and microsatellite instability status in their primary tumors. Survival end points were analyzed by Kaplan-Meier survival estimates and log-rank tests. RESULTS: A total of 817 SLNs were identified in 206 (97 %) of the 213 included patients. Routine histological examination of SLNs and other regional lymph nodes identified 63 patients with positive nodes (pN+), of which 42 (67 %) were positive in one or more SLNs (sensitivity 67 %, false-negative rate 33 %). On the basis of the CK20 and MUC2 mRNA levels in SLNs, occult metastases were suggested in 86 (60 %) and 52 (36 %) of the 143 otherwise LN-negative (pN0) patients, respectively. Survival analysis with a median 3.6-year follow-up revealed that MUC2 mRNA quantification had significant prognostic value in SLNs from all patients; however, occult SLN metastasis detection did not. CONCLUSIONS: Occult SLN metastases detected by CK20 and MUC2 mRNA quantification had limited prognostic value.

Comparison of the effect of different techniques for measurement of Ki67 proliferation on reproducibility and prognosis prediction accuracy in breast cancer.

AIMS: The proliferation factor Ki67 is prognostic in breast cancer and included in international therapy guidelines, but measurement procedures differ between laboratories. We compared the reproducibility and prognostic value of different Ki67 sampling and measurement methods. METHODS AND RESULTS: In 237 T(1,2) N(0) M(0) breast cancers without adjuvant systemic treatment, strictly standardized section thickness, automated antigen retrieval and immunohistochemistry were used. The percentages of Ki67-positive nuclei were assessed using (i) a 'quick-scan rapid estimate', (ii) ocular-square-guided counts by independent pathologists, (iii) computerized point-grid-sampling interactive morphometry (CIM) and (iv) automated digital image analysis (DIA). Quick-scan rapid estimates were poorly reproducible. The optimal prognostic thresholds of Ki67 counts by two pathologists differed greatly (4%, 14%; kappa: 0.36), with many therapeutic differences. CIM-Ki67 and DIA-Ki67 were strongly prognostic (P<0.0001) and reproducible. DIA-Ki67 (threshold: 6.5%) was the strongest and most robust prognosticator (the threshold could vary from 4 to 15% without significant prognostic loss). Ki67 was prognostically strongest in the periphery of the tumour. CONCLUSION: In node-negative breast cancer without adjuvant systemic treatment, Ki67% by DIA, but not subjective counts, is reproducible and prognostically strong. This casts serious doubt on therapeutic guidelines using subjective counts of Ki67.

Persistent tumor cells in bone marrow of non-metastatic breast cancer patients after primary surgery are associated with inferior outcome.

BACKGROUND: To investigate the prognostic significance of disseminated tumor cells (DTCs) in bone marrow (BM) from non-metastatic breast cancer patients before and after surgery. METHODS: Patients with non-metastatic breast cancer were consecutively recruited to this project during the years 1998-2000. Real-time RT-PCR quantification of a DTC multimarker panel consisting of cytokeratin 19, mammaglobin A and TWIST1 mRNA was performed in BM samples obtained from 154 patients three weeks (BM2) and/or six months after surgery (BM3). The results were compared to previously published data from pre-operative BM analyses for the same patients. RESULTS: DTCs were identified in post-operative BM samples (BM2 and/or BM3) from 23 (15%) of the 154 patients investigated. During a median follow-up of 98 months, 10 (44%) of these patients experienced systemic relapse as compared to 16 (12%) of 131 DTC-negative patients. Kaplan-Meier estimates of systemic recurrence-free- and breast-cancer specific survival demonstrated significantly shorter survival for patients with persistent DTCs in BM after surgery (p≤0.001). By multivariate Cox regression analyses, persistent DTCs after surgery was an independent predictor of both systemic recurrence-free- (HR = 5.4, p < 0.001) and breast-cancer specific survival (HR = 5.3, p < 0.001). Furthermore, the prognostic value of DTCs in BM was similar for pre- and post surgery samples. However, patients with DTCs both before and after surgery (BM1 and BM2/3) had a particularly poor prognosis (systemic recurrence-free survival: HR = 7.2, p < 0.0001 and breast-cancer specific survival: HR = 8.0, p < 0.0001). CONCLUSIONS: Detection of persistent DTCs in BM samples obtained after surgery identified non-metastatic breast cancer patients at high risk for systemic relapse, and with reduced breast-cancer specific survival. Furthermore, patients with positive DTC status both before and after surgery had a particularly poor prognosis.

miRNA expression profiling for identification of potential breast cancer biomarkers.

To identify micro RNA (miRNA) biomarker candidates for early detection of breast cancer and detection of minimal residual breast cancer, we performed miRNA expression profiling in pooled RNA samples from breast tumors, and from bone marrow mononuclear cells, peripheral blood mononuclear cells and plasma from healthy controls. We found substantially higher levels of five miRNAs in the breast tumors compared to the normal samples. However, validation of these miRNA levels, and seven other candidates selected from the literature, in individual samples from healthy controls and patients with non-metastatic breast cancer did not suggest further examination of their biomarker potential.

Mitotic activity and bone marrow micrometastases have independent prognostic value in node positive breast cancer patients.

The purpose of this article is to investigate the prognostic value of the mitotic activity index (MAI) and the presence of disseminated tumor cells (DTCs) in bone marrow (BM), in clinically operable breast cancer patients. We compared routinely assessed MAI, classic prognosticators and BM DTCs, detected by a real-time RT-PCR multimarker assay including cytokeratin 19, mammaglobin A and TWIST1 mRNA, in 179 consecutive patients with operable breast cancer. Over a median follow-up of 96 months (range: 1-126 months), 31 (17.3%) patients experienced a systemic relapse and 26 (14.5%) died of breast cancer-related causes. MAI (≥ 10) was strongly associated with breast cancer-related death in lymph node (LN)-negative patients (hazard ratio (HR): 7.0, confidence interval (CI) 1.74-27.9), whereas both BM DTC-status (HR: 3.3, CI 1.25-8.52) and MAI (HR: 3.1, CI 1.08-8.8) were significant in LN-positive patients. With multivariate Cox regression, MAI was the only significant predictor of breast cancer-specific survival (HR 7.0, CI 1.7-27.9) in LN-negative patients. In LN-positive patients, both BM DTC-status and MAI were strong independent predictors of breast cancer-specific survival (HR 3.3, CI 1.25-8.49 and HR 3.1, CI 1.1-8.9), respectively. Where, however, MAI and BM DTC-status as single parameters were replaced by a combination of these, this showed to be the most significant prognostic marker in both LN-negative (HR 7.7, CI 1.2-50) and LN-positive (HR 6.0, CI 1.4 to 26.4) patients with regard to breast cancer-specific survival. A combination of MAI and BM DTC detection identified both LN-negative and LN-positive breast cancer patients with poor prognosis.

Heterogeneous distribution of K-ras mutations in primary colon carcinomas: implications for EGFR-directed therapy.

PURPOSE: K-ras mutations predict resistance against epidermal growth factor receptor (EGFR)-directed therapy of metastatic colorectal cancer (CRC). The purpose of this study was to analyze the distribution of K-ras mutations in primary tumors and corresponding sentinel lymph nodes (SLNs) from colon cancer patients. METHODS: Tumor biopsies and SLNs from 158 patients with non-metastatic colon cancer were analyzed for K-ras mutations in codons 12 and 13 by a sensitive and quantitative peptide nucleic acid clamp PCR assay. RESULTS: Analyses of single fresh-frozen tumor biopsies revealed K-ras mutations in 67 (42%) of the patients. Apparently low levels of K-ras mutations in 13 of the mutated primary tumors and the presence of K-ras mutations in SLNs from seven patients with a wild-type primary tumor biopsy suggested possible intratumoral heterogeneity for 20 of the patients. To confirm this hypothesis, we analyzed tissue sections from all available formalin-fixed, paraffin-embedded (FFPE) tumor blocks from these 20 patients. Ten of the patients had a mixture of tissue sections positive and tissue sections negative for K-ras mutations, two patients had K-ras mutations in all sections, and eight patients had no detectable K-ras mutations in tumor FFPE tissue blocks. Among these eight patients, five had K-ras mutations detected in SLNs. Thus, evidence supporting a heterogeneous distribution of K-ras mutations was obtained for 15 patients. CONCLUSIONS: Heterogeneous distribution of K-ras codon 12 and 13 mutations within primary tumor, or between primary tumor and lymph node metastases, was demonstrated for 15 (20%) of 74 colon cancer patients having K-ras mutations. This may have implications for tissue sampling routines with regard to EGFR-directed therapy of CRC, both in adjuvant and metastatic settings.

Detection of occult metastases in sentinel lymph nodes from colon cancer patients by K-ras mutation peptide nucleic acid clamp PCR.

OBJECTIVE: To identify colon cancer patients with occult lymph node metastases. SUMMARY OF BACKGROUND DATA: The prognostic value of regional lymph node (LN) metastases in colorectal cancer patients is well established. The disease recurrences nevertheless experienced by 20% to 30% of the LN negative patients suggest a potential for improvement in current LN diagnostics. We suspect that a subgroup of the patients that are LN negative by routine examination has occult LN metastases that are prognostically relevant. METHODS: To identify these patients we applied ex vivo sentinel lymph node (SLN) mapping to colon cancer patients and analyzed the SLNs by a sensitive peptide nucleic acid clamp PCR (polymerase chain reaction) assay for K-ras mutations, using these mutations as a surrogate marker for tumor cells. RESULTS: SLNs were identified in 158 (96%) of 164 prospectively recruited patients with localized colon cancer. Of the 158 patients with successful SLN mapping, 67 (42%) had K-ras mutations detected in their primary tumors. We analyzed the SLNs from these patients by peptide nucleic acid clamp PCR for K-ras mutations and found mutations in SLNs from 35 (52%) patients. At least one SLN from 14 (70%) of 20 patients with histologically proven regional LN metastases was positive for the K-ras mutation test. Interestingly, 21 (45%) of the 47 patients without known LN metastases had K-ras mutations detected in their SLNs. CONCLUSIONS: Sensitive detection of K-ras mutations in SLNs from colon cancer patients indicates the presence of occult metastases with potential prognostic implications.

High-dose chemoradiotherapy followed by surgery versus surgery alone in esophageal cancer: a retrospective cohort study.

BACKGROUND: We aimed to assess whether high-dose preoperative chemoradiotherapy (CRT) improves outcome in esophageal cancer patients compared to surgery alone and to define possible prognostic factors for overall survival. METHODS: Hundred-and-seven patients with disease stage IIA - III were treated with either surgery alone (n = 45) or high-dose preoperative CRT (n = 62). The data were collected retrospectively. Sixty-seven patients had adenocarcinomas, 39 squamous cell carcinomas and one undifferentiated carcinoma. CRT was given as three intensive chemotherapy courses by cisplatin 100 mg/m2 on day 1 and 5-fluorouracil 1000 mg/m2/day, from day 1 through day 5 as continuous infusion. One course was given every 21 days. The last two courses were given concurrent with high-dose radiotherapy, 2 Gy/fraction and a median dose of 66 Gy. Kaplan-Meier survival analysis with log rank test was used to obtain survival data and Cox Regression multivariate analysis was used to define prognostic factors for overall survival. RESULTS: Toxicity grade 3 of CRT occurred in 30 (48.4%) patients and grade 4 in 24 (38.7%) patients of 62 patients. One patient died of neutropenic infection (grade 5). Fifty percent (31 patients) in the CRT group did undergo the planned surgery. Postoperative mortality rate was 9% and 10% in the surgery alone and CRT+ surgery groups, respectively (p = 1.0). Median overall survival was 11.1 and 31.4 months in the surgery alone and CRT+ surgery groups, respectively (log rank test, p = 0.042). In the surgery alone group one, 3 and 5 year survival rates were 44%, 24% and 16%, respectively and in the CRT+ surgery group they were 68%, 44% and 29%, respectively. By multivariate analysis we found that age of patient, performance status, alcoholism and >or= 4 pathological positive lymph nodes in resected specimen were significantly associated with overall survival, whereas high-dose preoperative CRT was not. CONCLUSION: We found no significant survival advantage in esophageal cancer stage IIA-III following preoperative high-dose CRT compared to surgery alone. Patient's age, performance status, alcohol abuse and number of positive lymph nodes were prognostic factors for overall survival.

Circadian variations in clock gene expression of human bone marrow CD34+ cells.

Time-dependent variations in clock gene expression have recently been observed in mouse hematopoietic cells, but the activity of these genes in human bone marrow (BM) has so far not been investigated. Since such data can be of considerable clinical interest for monitoring the dynamics in stem/progenitor cells, the authors have studied mRNA expression of the clock genes hPer1 , hPer2, hCry1, hCry2, hBmal1, hRev-erb alpha, and hClock in human hematopoietic CD34-positive (CD34( +)) cells. CD34(+) cells were isolated from the BM samples obtained from 10 healthy men at 6 times over 24 h. In addition, clock gene mRNA expression was analyzed in the whole BM in 3 subjects. Rhythms in serum cortisol, growth hormone, testosterone, and leukocyte counts documented that subjects exhibited standardized circadian patterns. All 7 clock genes were expressed both in CD34(+) cells and the whole BM, with some differences in magnitude between the 2 cell populations. A clear circadian rhythm was shown for hPer1, hPer2, and hCry2 expression in CD34(+) cells and for hPer1 in the whole BM, with maxima from early morning to midday. Similar to mouse hematopoietic cells, h Bmal1 was not oscillating rhythmically. The study demonstrates that clock gene expression in human BM stem/progenitor cells may be developmentally regulated, with strong or weaker circadian profiles as compared to those reported in other mature tissues.