Electrosurgical and Laser Therapy Tools for the Treatment of Malignant Central Airway Obstructions

Central airway obstruction (CAO) is associated with significant morbidity and increased mortality. Bronchoscopic electrosurgical and laser ablative tools have proven to be safe and effective instruments for the treatment of malignant CAO. Although therapeutic modalities such as electrocautery, argon plasma coagulation, and laser have been used for decades, additional tools including radiofrequency ablation catheters continue to be developed for the treatment of CAO. These modalities are considered safe in the hands of experienced operators, although serious complications can occur. This review describes various electrosurgical and laser therapy tools used for the treatment of malignant CAO along with the specific advantages and disadvantages of each device.

Saliva as a comparable-quality source of DNA for Whole Exome Sequencing on Ion platforms

BACKGROUND

Whole Exome Sequencing (WES) utilises overlapping fragments prone to sequencing artefacts. Saliva, a non-invasive source of DNA, has been successfully used in WES studies on various platforms. This study explored the validity and quality of DNA sourced from saliva compared to whole blood on an Ion Platform.

METHODS

DNA was extracted from both sample types from four individuals. WES, performed on the Ion Proton platform was assessed for quality metrics (Depth, Genotyping Quality, etc.) and variant identification for the same source sample-pairs.

RESULTS

No significant differences in quality metrics were identified between data obtained from whole blood and saliva samples, with several saliva samples demonstrating higher coverage depth. Variants within the same sample, from the two genomic DNA sources, had an average concordance similar to other studies and platforms with different chemistry.

CONCLUSION

Saliva-extracted DNA provides comparable sequencing quality to whole blood for WES on Ion Torrent Platforms.

Bronchoscope-Guided Percutaneous Endoscopic Gastrostomy Tube Placement by Interventional Pulmonologists: A Feasibility and Safety Study

BACKGROUND

Percutaneous endoscopic gastrostomy (PEG) tube placement is a procedure frequently done in the intensive care unit. The use of a traditional endoscope can be difficult in cases of esophageal stenosis and theoretically confers an increased risk of infection due to its complex architecture. We describe a technique using the bronchoscope, which allows navigation through stenotic esophageal lesions and also minimizes the risk of endoscopy-associated infections.

METHODS

Prospective series of patients who had PEG tube placement guided by a bronchoscope. Procedural outcomes including successful placement, duration of the entire procedure, time needed for passage of the bronchoscope from the oropharynx to the major curvature, PEG tube removal rate, and mortality were collected. Procedural adverse events, including infections and long-term PEG-related complications, were recorded.

RESULTS

A total of 84 patients underwent bronchoscope-guided PEG tube placement. Percutaneous endoscopic gastrostomy tube insertion was completed successfully in 82 (97.6%) patients. Percutaneous endoscopic gastrostomy tube placement was performed immediately following percutaneous tracheostomy in 82.1%. Thirty-day mortality and 1-year mortality were 11.9% and 31%, respectively. Overall, minor complications occurred in 2.4% of patients, while there were no major complications. No serious infectious complications were identified and no endoscope-associated hospital acquired infections were documented.

CONCLUSIONS

The use of the bronchoscope can be safely and effectively used for PEG tube placement. The use of bronchoscope rather than a gastroscope has several advantages, which include the ease of navigating through complex aerodigestive disorders such as strictures and fistulas as well as decreased health-care utilization. In addition, it may have a theoretical advantage of minimizing infections related to complex endoscopes.

Patterns of Corneal Topography after Penetrating Keratoplasty

Background

The topography of corneas after penetrating keratoplasty is highly variable. We classify the topography into five groups.

Methods

We performed videokeratography on 45 clear compact penetrating keratoplasties, with all sutures removed. Three ophthalmologists classified the keratographs independently into five previously defined topographic groups, based on the pattern of the normalized color-coded videokeratograph.

Results

The five topographic patterns included: prolate bow tie, 14 (30%); oblate bow tie, 14 (30%); mixed prolate and oblate bow tie, 8 (17%); asymmetric, 3 (9%); and steep/flat, 6 (14%). The three ophthalmologists agreed in their initial classification in 87% of the cases and after discussion, in 96%.

Conclusion

The topography of the cornea after penetrating keratoplasty can be classified into five qualitative groups by trained observers, with good clinical reliability.

Raman spectroscopy for cytopathology of exfoliated cervical cells

Cervical cancer is the fourth most common cancer affecting women worldwide but mortality can be decreased by early detection of pre-malignant lesions. The Pap smear test is the most commonly used method in cervical cancer screening programmes. Although specificity is high for this test, it is widely acknowledged that sensitivity can be poor mainly due to the subjective nature of the test. There is a need for new objective tests for the early detection of pre-malignant cervical lesions. Over the past two decades, Raman spectroscopy has emerged as a promising new technology for cancer screening and diagnosis. The aim of this study was to evaluate the potential of Raman spectroscopy for cervical cancer screening using both Cervical Intraepithelial Neoplasia (CIN) and Squamous Intraepithelial Lesion (SIL) classification terminology. ThinPrep® Pap samples were recruited from a cervical screening population. Raman spectra were recorded from single cell nuclei and subjected to multivariate statistical analysis. Normal and abnormal ThinPrep® samples were discriminated based on the biochemical fingerprint of the cells using Principal Component Analysis (PCA). Principal Component Analysis - Linear Discriminant Analysis (PCA-LDA) was employed to build classification models based on either CIN or SIL terminology. This study has shown that Raman spectroscopy can be successfully applied to the study of routine cervical cytology samples from a cervical screening programme and that the use of CIN terminology resulted in improved sensitivity for high grade cases.

Abstract C26: Analysis of stem cell number & potency in African-American breast tissue

Breast cancer (BC) survival among African-American (AA) women 5 years after initial diagnosis is only 74%, significantly lower than the 88% survival observed in women of European white (EW) ancestry. The differences in outcomes have been attributed to the greater prevalence of Triple Negative Breast Cancer (TNBC) in AA women and, indeed, stage for stage, TNBC is more lethal than luminal type BCs. Why AA women are more likely to develop TNBC remains a major question. In the past, disparities in BC outcomes were frequently attributed to socioeconomic factors, but increasing data suggests that it is based on intrinsic differences in AA breast tissue compared with EW. Risk factors for BC have been extensively investigated and include elements impacting breast differentiation and development, including timing of thelarche and menarche, as well as timing and number of pregnancies. Breast formation (thelarche) occurs in AA girls 2 years earlier than EW girls in the US. The purpose of this study was to better understand the etiology of premature thelarche and, by extension, BC etiology in AA women. We utilized a unique tissue engineering system that our laboratory has developed for culture of human breast epithelial cells, both normal and malignant. This system allows for long-term (>3 months) growth of normal primary epithelial cell cultures. These cultures form 3-dimensional “epispheres,” made up of 40-100 epithelial cells, which can then differentiate into organotypic branching ducts and lobules. We have established explant cultures of normal breast epithelial cells from 48/48 non-diseased women undergoing breast reduction mammoplasty. Twelve of these (25%) were AA women socioeconomically matched with the EW women. Analysis of these cultures resulted in a significant multivariate model for the timing of ductal formation (P = 0.005) involving only the ancestry of the donor and her height. Thus, intrinsic biological differences exist between AA and EW breast tissue that might impact upon the incidence or etiology of BC. We hypothesized that stem cells from AA women would be present in higher proportions or alternatively demonstrate higher potency than EW. Breast epithelial stem cells were defined by the absence of CD24 antigen and the presence of CD44 and CD49f antigens on the cell surface using quantitative flow cytometric analysis. Cloning efficiency, defined as sorted single cells that grew into colonies, was quantified as a percentage of the total cells sorted and verified microscopically. Potency, defined as colonies that exhibited multiple cell types, was quantified as a percentage of the total cloning efficiency. Our results indicate that AA samples, on average, contained 48.4% breast stem cells, while EW samples manifested a significantly smaller proportion, only 7.2% (P = 0.018). Cloning efficiency and potency analyses are currently ongoing. In summary AA women display higher proportions of stem cells in normal breast tissues relative to EW, which may be pertinent to premature thelarche and by extension, triple negative breast cancer etiology.

Citation Format: Omar Ibrahim, Stephen G. Grant, Nicole T. Myers, Amie B. Courtney, Nancy A. lalanne, Jean J. Latimer. Analysis of stem cell number & potency in African-American breast tissue. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C26.

CURRENT STATUS AND OUTLOOK OF RENEWABLE ENERGY DEVELOPMENT IN NIGERIA

Over 80% of the current Nigerian primary energy consumption is met by petroleum. This overdependence on fossil fuels derived from petroleum for local consumption requirements should be a serious source of concern for the country in two ways – depletion of the resources and negative impact on the environment. This paper presents a critical review of the available renewable energy resources in Nigeria, namely; biomass, hydropower, solar and wind energy. It examines the current energy situation in the country and equally discusses the various energy policy documents developed by the government. Using the scenario-based International Atomic Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this study shows that Nigeria will overcome her present energy crisis if she explores the abundant renewable energy resources in the country.  The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria.  http://dx.doi.org/10.4314/njt.v36i1.25

Abstract 3589: Nucleotide excision repair is elevated in stage IV commonly used breast cancer cell lines as compared to stage I breast tumor explants

Genomic instability is a hallmark of human carcinogenesis. We have previously published that sporadic stage I breast tumors exhibit deficient Nucleotide Excision Repair (NER) capacity relative to non-diseased breast reduction primary cultures (Latimer et al., 2010). In the present work, we hypothesized that this feature of early human breast cancer would not be maintained in cell lines established from late stage tumors. Our objective was to determine functional NER capacity and relative NER gene expression in a series of commonly used stage IV breast cancer-derived cell lines relative to stage I breast cancer explants and cell lines. NER capacity was determined using the functional unscheduled DNA synthesis (UDS) assay in six established breast cancer cell lines (MCF-7, MCF-7LY2, MDA-MB-231, SK-BR-3, CAMA-1, BT-20). JL BTL-12 (Jean Latimer Breast Tumor Line-12), derived from a stage III breast tumor, was included to represent an advanced stage tumor cell line established using our culture system. The NER capacity of the cell lines was compared to that of 19 stage I breast tumor primary cultures. NER gene expression was determined by expression microarray using the Affymetrix HG U-133 plus 2.0 chip in five of these established cell lines (MCF-7, MDA-MB-231, SK-BR-3, CAMA-1, BT-20), JL BTL-12 and a representative stage I tumor-derived cell line (JL BTL-8, Breast Tumor Line-8). The stage IV cell lines and JL BTL-12 all manifested significantly higher NER capacity than explants of stage I breast cancer. Unsupervised as well as supervised analyses, based on expression of the canonical 20 NER genes, placed JL BTL-12 and the five stage IV commercial cell lines in one cluster, while JL BTL-8 clustered separately. Four NER genes were significantly upregulated in JL BTL-12 and all commercial cell lines relative to JL BTL-8. In conclusion, based on NER these five cell lines commonly used in breast cancer research are more representative of late stage disease than early stage breast cancer, regardless of the type of breast cancer they represent. The most commonly diagnosed stage of breast cancer in the U.S. is now stage I, and it is now possible to study stage I cell lines or explants.

Citation Format: Homood As Sobeai, Jennifer M. Johnson, Nancy Lalanne, Omar Ibrahim, Stephen G. Grant, Sharon L. Wenger, Jean J. Latimer. Nucleotide excision repair is elevated in stage IV commonly used breast cancer cell lines as compared to stage I breast tumor explants. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3589.