Afsaneh Barzi

Molecular Pathways: Estrogen Pathway in Colorectal Cancer

Worldwide, colorectal cancer has a higher incidence rate in men than in women, suggesting a protective role for sex hormones in the development of the disease. Preclinical data support a role for estrogen and its receptors in the initiation and progression of colorectal cancer and establishes that protective effects of estrogen are exerted through ERβ. Hormone replacement therapy (HRT) in postmenopausal women as well as consumption of soy reduces the incidence of colorectal cancer. In the Womens Health Initiative trial, use of HRT in postmenopausal women reduced the risk of colon cancer by 56% [95% confidence interval (CI), 0.38–0.81; P = 0.003]. A recent meta-analysis showed that in women, consumption of soy reduced the risk of colon cancer by 21% (95% CI, 0.03–0.35; P = 0.026). In this review, using the preclinical data, we translate the findings in the clinical trials and observational studies to define the role of estrogen in the prevention of colorectal cancer. We hypothesize that sometime during the tumorigenesis process ERβ expression in colonocytes is lost and the estrogen ligand, HRT, or soy products, exerts its effects through preventing this loss. Thus, in the adenoma-to-carcinoma continuum, timing of HRT is a significant determinant of the observed benefit from this intervention. We further argue that the protective effects of estrogen are limited to certain molecular subtypes. Successful development of estrogen modulators for prevention of colorectal cancer depends on identification of susceptible colorectal cancer population(s). Thus, research to better understand the estrogen pathway is fundamental for clinical delivery of these agents. Clin Cancer Res; 19(21); 5842–8. ©2013 AACR.

A Bayesian model for triage decision support.

OBJECTIVE To compare triage decisions of an automated emergency department triage system with decisions made by an emergency specialist. METHODS In a retrospective setting, data extracted from charts of 90 patients with chief complaint of non-traumatic abdominal pain were used as input for triage system and emergency medicine specialist. The final disposition and diagnoses of the physicians who visited the patient in Emergency Department (ED) as reflected in the medical records were considered as control. Results were compared by chi(2)-test and a binary logistic regression model. RESULTS Compared to emergency medicine specialist, triage system had higher sensitivity (90% versus 64%) and lower specificity (25% versus 48%) for patients who required hospitalization. The triage system successfully predicted the Admit decisions made in the ED whereas the emergency medicine specialist decisions could not predict the ED disposition. Both triage system and emergency medicine specialist properly disposed 56% of cases, however, the emergency medicine specialist in this study under-disposed more patients than the triage system considering Admit disposition (p=0.004) while he appropriately discharged more patients compared to the triage system (p=0.017). CONCLUSION The triage system studied here shows promise as a triage decision support tool to be used for telephone triage and triage in the emergency departments. This technology may also be useful to the patients as a self-triage tool. However, the efficiency of this particular application of this technology is unclear.

Myelodysplastic syndromes: A practical approach to diagnosis and treatment

The myelodysplastic syndromes (MDS) are clonal bone marrow disorders that lead to underproduction of normal blood cells. The consequent cytopenias result in infections and bleeding complications. MDS transform to acute myeloid leukemia in one-third of patients. The number of diagnoses has exploded in the past decade as a result of increased recognition and understanding of the disease and the aging of the population. New therapies can extend life. MDS are now considered the most common form of leukemia, and in some cases deserve immediate intervention. This review describes common presentations of MDS, optimal diagnostic approaches, and therapies for lower- and higher-risk disease. The myelodysplastic syndromes are clonal bone marrow disorders that lead to underproduction of normal blood cells. Primary care physicians tend to be the first to identify the problem.

Comparative Effectiveness of Screening Strategies for Lynch Syndrome

BACKGROUND Colorectal cancer is the second leading cause of cancer death in the United States. Approximately 3% of colorectal cancers are associated with Lynch Syndrome. Controversy exists regarding the optimal screening strategy for Lynch Syndrome. METHODS Using an individual level microsimulation of a population affected by Lynch syndrome over several years, effectiveness and cost-effectiveness of 21 screening strategies were compared. Modeling assumptions were based upon published literature, and sensitivity analyses were performed for key assumptions. In a two-step process, the number of Lynch syndrome diagnoses (Step 1) and life-years gained as a result of foreknowledge of Lynch syndrome in otherwise healthy carriers (Step 2) were measured. RESULTS The optimal strategy was sequential screening for probands starting with a predictive model, then immunohistochemistry for mismatch repair protein expression (IHC), followed by germline mutation testing (incremental cost-effectiveness ratio [ICER] of

Distinct gene expression profiles of proximal and distal colorectal cancer: implications for cytotoxic and targeted therapy.

35 143 per life-year gained). The strategies of IHC + BRAF, germline testing and universal germline testing of colon cancer probands had ICERs of

Timeliness of Adjuvant Chemotherapy for Stage III Adenocarcinoma of the Colon: A Measure of Quality of Care

144 117 and

Mutation-enrichment next-generation sequencing for quantitative detection of KRAS mutations in urine cell-free DNA from patients with advanced cancers

996 878, respectively. CONCLUSIONS This analysis suggests that the initial step in screening for Lynch Syndrome should be the use of predictive models in probands. Universal tumor testing and general population screening strategies are not cost-effective. When family history is unavailable, alternate strategies are appropriate. Documentation of family history and screening for Lynch Syndrome using a predictive model may be considered a quality-of-care measure for patients with colorectal cancer.

Prognostic Role of Lemur Tyrosine Kinase-3 Germline Polymorphisms in Adjuvant Gastric Cancer in Japan and the United States

Colorectal cancer (CRC) is a heterogeneous disease with genetic profiles and clinical outcomes dependent on the anatomic location of the primary tumor. How location has an impact on the molecular makeup of a tumor and how prognostic and predictive biomarkers differ between proximal versus distal colon cancers is not well established. We investigated the associations between tumor location, KRAS and BRAF mutation status, and the messenger RNA (mRNA) expression of proteins involved in major signaling pathways, including tumor growth (epidermal growth factor receptor (EGFR)), angiogenesis (vascular endothelial growth factor receptor 2 (VEGFR2)), DNA repair (excision repair cross complement group 1 (ERCC1)) and fluoropyrimidine metabolism (thymidylate synthase (TS)). Formalin-fixed paraffin-embedded tumor specimens from 431 advanced CRC patients were analyzed. The presence of seven different KRAS base substitutions and the BRAF V600E mutation was determined. ERCC1, TS, EGFR and VEGFR2 mRNA expression levels were detected by reverse transcriptase-PCR. BRAF mutations were significantly more common in the proximal colon (P<0.001), whereas KRAS mutations occurred at similar frequencies throughout the colorectum. Rectal cancers had significantly higher ERCC1 and VEGFR2 mRNA levels compared with distal and proximal colon tumors (P=0.001), and increased TS levels compared with distal colon cancers (P=0.02). Mutant KRAS status was associated with lower ERCC1, TS, EGFR and VEGFR2 gene expression in multivariate analysis. In a subgroup analysis, this association remained significant for all genes in the proximal colon and for VEGFR2 expression in rectal cancers. The mRNA expression patterns of predictive and prognostic biomarkers, as well as associations with KRAS and BRAF mutation status depend on primary tumor location. Prospective studies are warranted to confirm these findings and determine the underlying mechanisms.

Association of variants in genes encoding for macrophage-related functions with clinical outcome in patients with locoregional gastric cancer

BACKGROUND Findings from multiple clinical trials established AC as a standard of care for stage III colon cancer. However, there is no recommended standard time for delivery of AC. We explored the timeliness of AC with FOLFOX as a predictor of recurrence and its role as a quality indicator in patients with stage III colon cancer. PATIENTS AND METHODS We conducted a retrospective analysis of patients with colon cancer who received AC at Los Angeles County Hospital and Norris Cancer Center between 2003 and 2011. Time to recurrence (TTR) was the primary end point of the study, Kaplan-Meier curves and log-rank tests were used to assess the association between timing of the AC and TTR. RESULTS We identified 102 patients with stage III colon cancer who had received AC. With a median follow-up of 3.2 years, time from surgery to AC was not a predictor of recurrence (P = .19). However, there was a nonsignificant trend toward higher risk of systemic recurrence when the delay of AC was more than 12 weeks (P = .068). Additionally, a significant association was found between age, race, type of hospital, and timeliness of AC. CONCLUSION To date, our study is the largest data set to assess the timeliness of FOLFOX as a predictor of outcome in stage III colon cancer. Because FOLFOX is the current standard for AC for colon cancer, we report a trend toward worse outcome when FOLFOX is delayed more than 12 weeks. This result, thus supports quality measures to assess the timeliness of AC in stage III colon cancer and might have a meaningful effect on the care of patients with colon cancer.

Angiogenesis in esophageal and gastric cancer: a paradigm shift in treatment

Purpose: Tumor-derived cell-free DNA (cfDNA) from urine of patients with cancer offers noninvasive biological material for detection of cancer-related molecular abnormalities such as mutations in Exon 2 of KRAS. Experimental Design: A quantitative, mutation-enrichment next-generation sequencing test for detecting KRASG12/G13 mutations in urine cfDNA was developed, and results were compared with clinical testing of archival tumor tissue and plasma cfDNA from patients with advanced cancer. Results: With 90 to 110 mL of urine, the KRASG12/G13 cfDNA test had an analytical sensitivity of 0.002% to 0.006% mutant copies in wild-type background. In 71 patients, the concordance between urine cfDNA and tumor was 73% (sensitivity, 63%; specificity, 96%) for all patients and 89% (sensitivity, 80%; specificity, 100%) for patients with urine samples of 90 to 110 mL. Patients had significantly fewer KRASG12/G13 copies in urine cfDNA during systemic therapy than at baseline or disease progression (P = 0.002). Compared with no changes or increases in urine cfDNA KRASG12/G13 copies during therapy, decreases in these measures were associated with longer median time to treatment failure (P = 0.03). Conclusions: A quantitative, mutation-enrichment next-generation sequencing test for detecting KRASG12/G13 mutations in urine cfDNA had good concordance with testing of archival tumor tissue. Changes in mutated urine cfDNA were associated with time to treatment failure. Clin Cancer Res; 23(14); 3657–66. ©2017 AACR.