Composition and secondary formation of fine particulate matter in the Salt Lake Valley: winter 2009.

Under the National Ambient Air Quality Standards (NAAQS), put in place as a result of the Clean Air Amendments of 1990, three regions in the state of Utah are in violation of the NAAQS for PM10 and PM2.5 (Salt Lake County, Ogden City, and Utah County). These regions are susceptible to strong inversions that can persist for days to weeks. This meteorology, coupled with the metropolitan nature of these regions, contributes to its violation of the NAAQS for PM during the winter. During January-February 2009, 1-hr averaged concentrations of PM10-2.5, PM2.5, NO(x), NO2, NO, O3, CO, and NH3 were measured. Particulate-phase nitrate, nitrite, and sulfate and gas-phase HONO, HNO3, and SO2 were also measured on a 1-hr average basis. The results indicate that ammonium nitrate averages 40% of the total PM2.5 mass in the absence of inversions and up to 69% during strong inversions. Also, the formation of ammonium nitrate is nitric acid limited. Overall, the lower boundary layer in the Salt Lake Valley appears to be oxidant and volatile organic carbon (VOC) limited with respect to ozone formation. The most effective way to reduce ammonium nitrate secondary particle formation during the inversions period is to reduce NO(x) emissions. However, a decrease in NO(x) will increase ozone concentrations. A better definition of the complete ozone isopleths would better inform this decision. Implications: Monitoring of air pollution constituents in Salt Lake City, UT, during periods in which PM2.5 concentrations exceeded the NAAQS, reveals that secondary aerosol formation for this region is NO(x) limited. Therefore, NO(x) emissions should be targeted in order to reduce secondary particle formation and PM2.5. Data also indicate that the highest concentrations of sulfur dioxide are associated with winds from the north-northwest, the location of several small refineries.

A Cohort Study of p53 Mutations and Protein Accumulation in Benign Breast Tissue and Subsequent Breast Cancer Risk.

Mutations in the p53 tumor suppressor gene and accumulation of its protein in breast tissue are thought to play a role in breast carcinogenesis. However, few studies have prospectively investigated the association of p53 immunopositivity and/or p53 alterations in women with benign breast disease in relation to the subsequent risk of invasive breast cancer. We carried out a case-control study nested within a large cohort of women biopsied for benign breast disease in order to address this question. After exclusions, 491 breast cancer cases and 471 controls were available for analysis. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Neither p53 immunopositivity nor genetic alterations in p53 (either missense mutations or polymorphisms) was associated with altered risk of subsequent breast cancer. However, the combination of both p53 immunopositivity and any p53 nucleotide change was associated with an approximate 5-fold nonsignificant increase in risk (adjusted OR 4.79, 95% CI 0.28-82.31) but the confidence intervals were extremely wide. Our findings raise the possibility that the combination of p53 protein accumulation and the presence of genetic alterations may identify a group at increased risk of breast cancer.

Immunohistochemical and molecular markers in breast phyllodes tumors.

Phyllodes tumors of the breast are diagnostically and managerially enigmatic, as their malignant potential is difficult to predict based on the standard morphologic criteria. Thus, there is a need for additional markers of biologic potential. Although a number of ancillary tests have been reported, consensus in the literature is lacking. We studied 38 cellular fibroadenomas and phyllodes tumors of various grade (World Health Organization benign, borderline, and malignant) with a panel of immunohistochemical stains (p53, CD117, phospho-Histone3, mdm2, cdk4) and screened 26 of the tumors for mutations across 30 cancer-related genes using PCR and mass-spectrometry based methods. p53 and phospho-Histone3 (mitotic marker) showed increased staining in higher grade phyllodes tumors. CD117, mdm2, and cdk4 showed no difference in expression across different grades of phyllodes tumors. Mutational analysis revealed an S8R substitution in FBX4 (an E3 ubiquitin ligase) in 3 cases: 1 benign and 2 borderline. The S8R substitution seems to be more common in phyllodes tumors (11.5%) as compared with other cancers. FBX4 S8R cases had high cyclin D1 expression, but this finding was not specific. Our data support earlier studies showing that p53 has potential use in pathologic assessment of phyllodes tumors, and we newly characterized phospho-Histone3 for this application. Further studies are needed to characterize the molecular pathogenesis of the phyllodes tumors, as we were unable to identify activating mutations despite screening for a large panel of activating hotspot mutations. The significance of the FBX4 substitution deserves further investigation.

Risk factors for breast cancer in women biopsied for benign breast disease: a nested case-control study.

AIM: Women with a history of benign breast disease are at increased risk of subsequent breast cancer. However, few studies have examined whether established breast cancer risk factors other than histology are associated with an altered risk of breast cancer in women with benign breast disease. We used a nested case-control design within a large, multi-center cohort of women biopsied for benign breast disease (BBD) to estimate odds ratios for breast cancer in association with exposure to a range of personal and lifestyle factors. METHODS: Cases were women biopsied for BBD who subsequently developed breast cancer; controls were individually matched to cases on center and age at diagnosis and were women biopsied for BBD who did not develop breast cancer in the same follow-up interval as that for the cases. After excluding women with prevalent breast cancer, 1357 records (661 case records and 696 records) were available for analysis. We used conditional logistic regression to obtain crude and multivariable-adjusted estimates of the association between specific factors and risk of breast cancer. RESULTS: In multivariable analyses age at first live birth, number of pregnancies, and postmenopausal status were inversely associated with risk of breast cancer. The odds ratio for women with age at first birth <25 years and >or=3 pregnancies, relative to nulliparous women, was 0.49, 95% confidence interval 0.13-0.79, and that for postmenopausal women relative to premenopausal women was 0.60, 95% CI 0.37-0.99. CONCLUSIONS: Further study of personal factors influencing the risk of breast cancer in women with BBD may help to identify subgroups of the population at increased risk of invasive disease.

A multi-center prospective cohort study of benign breast disease and risk of subsequent breast cancer.

OBJECTIVE: We used a nested case-control design within a large, multi-center cohort of women who underwent a biopsy for benign breast disease (BBD) to assess the association of broad histologic groupings and specific histologic entities with risk of breast cancer. METHODS: Cases were all women who had a biopsy for BBD and who subsequently developed breast cancer; controls were individually matched to cases and were women with a biopsy for BBD who did not develop breast cancer in the same follow-up interval as that for the cases. After exclusions, 1,239 records (615 cases and 624 controls) were available for analysis. We used conditional logistic regression to estimate odds ratios and 95% confidence intervals (CIs). RESULTS: Relative to non-proliferative BBD/normal pathology, the multivariable-adjusted odds ratio for proliferative lesions without atypia was 1.45 (95% CI 1.10-1.90), and that for atypical hyperplasia was 5.27 (95% CI 2.29-12.15). The presence of multiple foci of columnar cell hyperplasia and of complex fibroadenoma without atypia was associated with a non-significantly increased risk of breast cancer, whereas sclerosing adenosis, radial scar, and papilloma showed no association with risk. CONCLUSION: Our results indicate that, compared to women with normal pathology/non-proliferative disease, women with proliferative disease without atypia have a modestly increased risk of breast cancer, whereas women with atypical hyperplasia have a substantially increased risk.

High prevalence of PIK3CA/AKT pathway mutations in papillary neoplasms of the breast.

Papillary lesions of the breast have an uncertain relationship to the histogenesis of breast carcinoma, and are thus diagnostically and managerially challenging. Molecular genetic studies have provided evidence that ductal carcinoma in situ and even atypical ductal hyperplasia are precursors of invasive carcinoma. However, papillary lesions have been seldom studied. We screened papillary breast neoplasms for activating point mutations in PIK3CA, AKT1, and RAS protein-family members, which are common in invasive ductal carcinomas. DNA extracts were prepared from sections of 89 papillary lesions, including 61 benign papillomas (28 without significant hyperplasia; 33 with moderate to florid hyperplasia), 11 papillomas with atypical ductal hyperplasia, 7 papillomas with carcinoma in situ, and 10 papillary carcinomas. Extracts were screened for PIK3CA and AKT1 mutations using mass spectrometry; cases that were negative were further screened for mutations in AKT2, BRAF, CDK, EGFR, ERBB2, KRAS, NRAS, and HRAS. Mutations were confirmed by sequencing or HPLC assay. A total of 55 of 89 papillary neoplasms harbored mutations (62%), predominantly in AKT1 (E17K, 27 cases) and PIK3CA (exon 20 >exon 9, 27 cases). Papillomas had more mutations in AKT1 (54%) than in PIK3CA (21%), whereas papillomas with hyperplasia had more PIK3CA (42%) than AKT1 (15%) mutations, as did papillomas with atypical ductal hyperplasia (PIK3CA 45%, AKT1 27%, and NRAS 9%). Among seven papillomas with carcinoma in situ, three had AKT1 mutations. The 10 papillary carcinomas showed an overall lower frequency of mutations, including 1 with an AKT1 mutation (in a tumor arising from a papilloma), 1 with an NRAS gene mutation (Q61H), and 2 with PIK3CA mutations (1 overlapping with the NRAS Q61H). These findings indicate that approximately two-thirds of papillomas are driven by mutations in the PI3CA/AKT pathway. Some papillary carcinomas may arise from these lesions, but others may have different molecular origins.

Comparison of speciation sampler and PC-BOSS fine particulate matter organic material results obtained in Lindon, Utah, during winter 2001-2002.

The Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) has been previously verified as being capable of measuring total fine particulate matter (PM2.5), including semi-volatile species. The present study was conducted to determine if the simple modification of a commercial speciation sampler with a charcoal denuder followed by a filter pack containing a quartz filter and a charcoal-impregnated glass (CIG) fiber filter would allow for the measurement of total PM2.5, including semi-volatile organic material. Data were collected using an R&P (Rupprecht and Pastasnik Co., Inc.) Partisol Model 2300 speciation sampler; an R&P Partisol speciation sampler modified with a BOSS denuder, followed by a filter pack with a quartz and a CIG filter; a Met One spiral aerosol speciation sampler (SASS); and the PC-BOSS from November 2001 to March 2002 at a U.S. Environmental Protection Agency (EPA) Science to Achieve Results (STAR) sampling site in Lindon, UT. Total PM2.5 mass, ammonium nitrate (both nonvolatile and semi-volatile), ammonium sulfate, organic carbon (both non-volatile and semi-volatile), and elemental carbon were determined on a 24-hr basis. Results obtained with the individual samplers were compared to determine the capability of the modified R&P speciation sampler for measuring total PM2.5, including semi-volatile components. Data obtained with the modified speciation sampler agreed with the PC-BOSS results. Data obtained with the two unmodified speciation samplers were low by an average of 26% because of the loss of semi-volatile organic material from the quartz filter during sample collection.

Levels of zinc, selenium, calcium, and iron in benign breast tissue and risk of subsequent breast cancer.

Previous studies that have assessed breast cancer in relation to zinc, selenium, calcium, and iron have yielded inconsistent results but have not measured breast tissue levels. In a case-control study involving 252 matched pairs nested in a cohort of 9,315 women with benign breast disease, we investigated these associations by directly measuring elemental levels in breast tissue using X-ray fluorescence spectroscopy. Quintile analyses revealed positive associations of breast cancer, of borderline statistical significance, with zinc [highest versus lowest quintile: odds ratio (OR), 1.37; 95% confidence limit (95% CL), 0.91, 2.05; P(trend) = 0.04], iron (highest versus lowest quintile: OR, 1.58; 95% CL, 1.02, 2.44; P(trend) = 0.07), and calcium (highest versus lowest quintile: OR, 1.46; 95% CL, 0.98, 2.17; P(trend) = 0.14), but little association with selenium (highest versus lowest quintile: OR, 1.10; 95% CL, 0.72, 1.68; P(trend) = 0.76). The associations were weakened by mutual adjustment. Furthermore, after stratification by menopausal status, the positive association between iron and breast cancer was confined to postmenopausal women (highest versus lowest quintile: OR, 2.77; 95% CL, 1.25, 6.13; P(trend) = 0.008), whereas the associations for zinc, calcium, and selenium did not differ by menopausal stratum. In conclusion, our data raise the possibility that relatively high levels of zinc, iron, and calcium in benign breast tissue may be associated with a modest increase in risk of subsequent breast cancer.

Splenic marginal zone lymphoma with micronodular T-cell rich B-cell lymphoma.

The types of B-cell lymphoma commonly involving the spleen include splenic marginal zone lymphoma and T-cell/histiocyte-rich large B-cell lymphoma. We describe a unique case of splenic marginal zone lymphoma associated with micronodular T cell/histiocyte-rich large B-cell lymphoma in the red pulp, a combination that has not previously reported in the literature.

Breast carcinoma malignancy grading by Bloom-Richardson system vs proliferation index: reproducibility of grade and advantages of proliferation index.

Questions of reproducibility and efficacy of histologic malignancy grading relative to alternative proliferation index measurements for outcome prediction remain unanswered. Microsections of specimens from the Cooperative Breast Cancer Tissue Resource (CBCTR) were evaluated by seven pathologists for reproducibility of grade and classification. Nuclear figure classification was assessed using photographs. Grade was assigned by the Bloom-Richardson method, Nottingham modification. Proliferation index was evaluated prospectively by deoxyribose nucleic acid precursor uptake with thymidine (autoradiographic) or bromodeoxyuridine (immunohistochemical) labeling index using fresh tissue from 631 node-negative breast cancer patients accessioned at St Luke's Hospital. A modified Nottingham-Bloom-Richardson grade was derived from histopathologic data. Median post-treatment observation was 6.4 years. Agreement on classification of nuclear figures (N=43) was less than good by kappa statistic (kappa=0.38). Grade was moderately reproducible in four trials (N=10,10,19, 10) with CBCTR specimens (kappa=0.50-0.59). Of components of Bloom-Richardson grade, agreement was least for nuclear pleomorphism (kappa=0.37-0.50), best for tubularity (kappa=0.57-0.83), and intermediate for mitotic count (kappa=0.45-0.64). Bloom-Richardson grade was a univariate predictor of prognosis in node-negative St Luke's patients, and was improved when mitotic count was replaced by labeling index (low, mid, or high). When labeling index was added to a multivariate model containing tumor size and vessel invasion, grade was no longer a significant predictor of tumor-specific relapse-free or overall survival. Mitotic index predicted best when intervals were lowered to 0-2, 3-10, and >10 mitotic figures per ten 0.18 mm(2) high-power fields. We conclude that Nottingham-Bloom-Richardson grades remain only modestly reproducible. Prognostically useful components of grade are mitotic index and tubularity. The Nottingham-Bloom-Richardson system can be improved by lowering cutoffs for mitotic index and by counting 20-30 rather than 10 high-power fields. Measurement of proliferation index by immunohistochemically detectable markers will probably give superior prognostic results in comparison to grade.