Bone marrow is a complex organ responsible for the regulation of hematopoietic cell distribution throughout the human body. Patients receiving antineoplastic agents as a therapeutic intervention for hematologic malignancy often experience varying degrees of myelotoxicity. Antineoplastic agents cause hypocellularity in marrow resulting in a reduction in hematopoietic tissue activity and a corresponding decline in cell production. Quantifying the adverse effects on hematopoiesis is based on the properties of a single agent, the use of individual drugs within a combination chemotherapy regimen, and the course, or courses, of chemotherapy designed to treat cancer. The direct or indirect suppression of erythrocytes, granulocytes, and megakaryocytes has potential for multiple negative clinical consequences ranging from increased monitoring of blood counts to life-threatening infection and death. This review will provide an overview of the structure and function of competent adult bone marrow, describe the process of hematopoiesis, and characterize the myelotoxicities associated with common antineoplastic agents currently used in the treatment of cancer.
Abstract 3137: Functional analysis of the chr13q22.1 pancreatic cancer risk locus suggests allele-specific effects on DIS3 expression.
Abstract Pancreatic cancer is the 10th most common cancer and 4th most common cause of cancer mortality in the United States. A genome wide association study has revealed pancreatic cancer susceptibility loci on chromosomes 13q22.1, 1q32.1 and 5p15.33. The chr13q22.1 region contains the most significant of all risk SNPs, rs9543325, (P= 3.27 x 10−11) which is located in a gene desert. The nearest genes are KLF5, KLF12, PIBF1, DIS3 and BORA, which range in distance from 265kb to 586kb, respectively, from the most significant variants. Given the high linkage disequilibrium across this risk locus, there are many candidate functional variants to consider. Imputation in the region did not improve the signal but gave a set of highly correlated SNPs which likely includes the functional variant(s). In an effort to identify the functional variant(s) we performed eQTL analyses to test the association between the genotypes of these candidate SNPs and expression of nearby genes. Among 100 normal pancreatic tissue samples, DIS3 showed the strongest association with SNPs in our risk locus (P-values as low as 0.0004). Mutations in DIS3 have been identified in acute myeloid leukemia and multiple myeloma, and its expression has been correlated with metastatic potential in colorectal cancer, suggesting this gene could be important in pancreatic cancer biology. Chromosome Conformation Capture (3C) was performed to test for physical interactions between the risk locus and nearby genes. This assay confirmed the three dimensional proximity of the risk locus and DIS3 promoter. Sub-regions of the risk locus were then cloned upstream of a minimal promoter controlling luciferase expression to assay for potential allele specific enhancer/silencer activity. This assay revealed a sub-region downstream of rs9543325 that causes allele-specific silencing. These results suggest that a sub-region of the chr13q22.1 risk locus has allele-specific effects on DIS3 expression, which may have implications in the susceptibility to pancreatic cancer. Citation Format: Jason Hoskins, Abdisamad Ibrahim, Jinping Jia, Irene Collins, Hemang Parikh, Gloria M. Petersen, Laufey Amundadottir. Functional analysis of the chr13q22.1 pancreatic cancer risk locus suggests allele-specific effects on DIS3 expression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3137. doi:10.1158/1538-7445.AM2013-3137
Abstract 5015: Ablation of a disintegrin and metalloproteinase 10 (ADAM 10) induces significant pancreatic tumor heterogeneity and blocks cancer metastasis.
Abstract Pancreatic ductal adenocarcinoma (PDA) is the 4th leading cause of cancer related death in the U.S. This disease has a poor prognosis due to late detection and rapid progression to metastasis. ADAM10 is a membrane bound metalloproteinase responsible for shedding bioactive molecules and inducing regulated intra-membrane proteolysis of cell surface proteins such as Notch. Both ADAM10 and Notch are highly expressed in patients with PDA, with the latter being implicated in PDA progression. We have found that genetic ablation of ADAM10 in the KrasG12D/+;Ptf1aCre/+ mouse PDA model altered tumor character to favor a cystic phenotype, mixed with low grade pancreatic intraepithelial neoplasia (PanIN) and PDA. Though ADAM10 knockout mice retain the ability to form locally invasive cancer, they live 50% longer than control mice, essentially to a full 2-year life span. The phenotypes we observe closely mimic Notch-2 knockout mice, consistent with ADAM10’s role as the primary Notch activating proteinase. Further examination revealed that ADAM10 knockout mice did not show significant liver metastasis compared to control, despite their local invasiveness. The mechanism through which ADAM 10 controls a cancer cell's ability to establish distant metastases will be explored. Citation Format: Jason C. Hall, Howard C. Crawford. Ablation of a disintegrin and metalloproteinase 10 (ADAM 10) induces significant pancreatic tumor heterogeneity and blocks cancer metastasis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5015. doi:10.1158/1538-7445.AM2013-5015
Abstract 1208: Discovery of a previously undescribed cutaneous T-cell neoplasm with chromosomal rearrangements of 6p25.3.
Abstract Background: Cutaneous T-cell neoplasms display markedly heterogeneous clinical behavior despite often similar pathologic features. For example, transformed mycosis fungoides (tMF) has a poor prognosis and requires intensive therapy whereas lymphomatoid papulosis (LyP) is an indolent lymphoproliferative disorder with spontaneously resolving lesions. These entities have overlapping histologic features and no molecular tools currently exist to aid in subclassification. Methods: We identified 11 T-cell neoplasms with histologic appearances distinct from previously described cutaneous T-cell neoplasms but with features overlapping those of both tMF and LyP. The phenotypic and genetic characteristics of the tumors were studied using immunohistochemistry and fluorescence in situ hybridization, respectively. Clinical data on presentation, treatment, evolution of the lesions, and follow-up were obtained. Results: All patients were older adults (mean age, 75 yr; range, 67-88 yr; 9M:2F). Clinical presentations were similar, with papulonodular skin lesions (0.3-1.0 cm) restricted to a single body area in all but two patients. Histologically there was an extensive atypical lymphoid infiltrate in the epidermis and a dermal tumor containing large transformed cells with numerous mitotic figures and apoptotic bodies. All tumors had a T-cell phenotype and expressed CD30 in both dermal and epidermal components. No case expressed ALK. Most cases had a high proliferative rate (>80%) by Ki67 staining. FISH analysis demonstrated rearrangements of the DUSP22-IRF4 locus on 6p25.3 in all cases. No patient had evidence of systemic disease on imaging studies. In 4 untreated patients, papules began to regress spontaneously a few weeks after presentation, with complete resolution within a month or two. Seven patients were treated with local excision (with or without cryotherapy) or radiotherapy. All non-excised lesions ultimately regressed. All patients were alive at last follow-up (median, 21 mo; range, 7-150 mo). Cutaneous recurrences occurred in 5 patients. At last follow-up only 1 patient had active lesions, which were confined to the presenting site. The remaining 10 patients had been disease-free from 2 to 32 months. Conclusions: Despite pathologic features mimicking an aggressive lymphoma, the benign clinical course observed in all 11 patients suggests these cases represent a newly recognized subtype of LyP. These neoplasms are characterized by 6p25.3 rearrangements, representing the first recurrent genetic abnormality identified in LyP. In contrast, we previously have shown absence of these rearrangements in tMF. Distinction of LyP from tMF is critical in this older patient population unlikely to tolerate intensive therapy. Thus, detection of 6p25.3 rearrangements represents a new tool for molecular classification of cutaneous T-cell neoplasms. Citation Format: Andrew L. Feldman, Laszlo J. Karai, Marshall E. Kadin, Eric D. Hsi, Jason C. Sluzevich, Rhett P. Ketterling, Ryan A. Knudson. Discovery of a previously undescribed cutaneous T-cell neoplasm with chromosomal rearrangements of 6p25.3. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1208. doi:10.1158/1538-7445.AM2013-1208
The Psychological and Physiological Effects of Acute Occupational Stress in New Anesthesiology Residents
Abstract Background: Occupational stress in resident physicians has profound implications for wellness, professionalism, and patient care. This observational pilot trial measured psychological and physiological stress biomarkers before, during, and after the start of anesthesia residency. Methods: Eighteen physician interns scheduled to begin anesthesia residency were recruited for evaluation at three time points: baseline (collected remotely before residency in June 2013); first-month visit 1 (July); and follow-up visit 2 (residency months 3 to 5, September–November). Validated scales were used to measure stress, anxiety, resilience, and wellness at all three time points. During visits 1 and 2, the authors measured resting heart-rate variability, responses to laboratory mental stress (hemodynamic, catecholamine, cortisol, and interleukin-6), and chronic stress indices (C-reactive protein, 24-h ambulatory heart rate and blood pressure, 24-h urinary cortisol and catecholamines, overnight heart-rate variability). Results: Thirteen interns agreed to participate (72% enrollment). There were seven men and six women, aged 27 to 33 yr. The mean ± SD of all study variables are reported. Conclusion: The novelty of this report is the prospective design in a defined cohort of residents newly exposed to the similar occupational stress of the operating environment. Because of the paucity of literature specific to the measures and stress conditions in this investigation, no data were available to generate a priori definition of primary outcomes and a data analytic plan. These findings will allow power analysis for future design of trials examining occupational stress and stress-reducing interventions. Given the importance of physician burnout in our country, the impact of chronic stress on resident wellness requires further study.
Inadvertent Iatrogenic Misuse of Intravenous Diphenhydramine in an Adolescent: Implications for Routine Medication Administration
Key points Ano1, a Ca2+‐activated Cl− channel, is expressed in interstitial cells of Cajal (ICC) throughout the gut. We report here that it is required to maintain coordinated Ca2+ transients within myenteric ICC of mouse small intestine. Ca2+ transients in Ano1 WT mice were rhythmic and coordinated whereas uncoordinated Ca2+ transients were seen in knockout mice. Ca2+ transients were un‐coordinated following pharmacological block of Ano1 in WT mice using niflumic acid, 5‐nitro‐2‐(3‐phenylpropylamino) benzoic acid and 4,4′‐diisothiocyanato‐2,2′‐stilbenedisulfonic acid disodium salt. Transient knockdown of Ano1 in organotypic cultures with short hairpin RNA to Ano1 in WT tissues also caused loss of coordinated Ca2+ transients. Contractility of Ano1 knockout mouse intestinal segments in organ bath experiments was significantly decreased, less coordinated and non‐rhythmic. Spatiotemporal maps from knockout mouse small intestine also showed loss of phasic contractile activity. This study provides important information on the basic mechanisms driving coordinated contractile activity in the gastrointestinal tract. AbstractInterstitial cells of Cajal (ICC) are pacemaker cells that generate electrical activity to drive contractility in the gastrointestinal tract via ion channels. Ano1 (Tmem16a), a Ca2+‐activated Cl− channel, is an ion channel expressed in ICC. Genetic deletion of Ano1 in mice resulted in loss of slow waves in smooth muscle of small intestine. In this study, we show that Ano1 is required to maintain coordinated Ca2+ transients between myenteric ICC (ICC‐MY) of small intestine. First, we found spontaneous Ca2+ transients in ICC‐MY in both Ano1 WT and knockout (KO) mice. However, Ca2+ transients within the ICC‐MY network in Ano1 KO mice were uncoordinated, while ICC‐MY Ca2+ transients in Ano1 WT mice were rhythmic and coordinated. To confirm the role of Ano1 in the loss of Ca2+ transient coordination, we used pharmacological inhibitors of Ano1 activity and shRNA‐mediated knock down of Ano1 expression in organotypic cultures of Ano1 WT small intestine. Coordinated Ca2+ transients became uncoordinated using both these approaches, supporting the conclusion that Ano1 is required to maintain coordination/rhythmicity of Ca2+ transients. We next determined the effect on smooth muscle contractility using spatiotemporal maps of contractile activity in Ano1 KO and WT tissues. Significantly decreased contractility that appeared to be non‐rhythmic and uncoordinated was observed in Ano1 KO jejunum. In conclusion, Ano1 has a previously unidentified role in the regulation of coordinated gastrointestinal smooth muscle function through coordination of Ca2+ transients in ICC‐MY.
What Is the Gold Standard for Comprehensive Interinstitutional Communication of Perioperative Information for Thyroid Cancer Patients? A Comparison of Existing Electronic Health Records with the Current American Thyroid Association Recommendations
Background: Appropriate management of well-differentiated thyroid cancer requires treating clinicians to have access to critical elements of the patient's presentation, surgical management, postoperative course, and pathologic assessment. Electronic health records (EHRs) provide an effective method for the storage and transmission of patient information, although most commercially available EHRs are not intended to be disease-specific. In addition, there are significant challenges for the sharing of relevant clinical information when providers involved in the care of a patient with thyroid cancer are not connected by a common EHR. In 2012, the American Thyroid Association (ATA) defined the critical elements for optimal interclinician communication in a position paper entitled, “The Essential Elements of Interdisciplinary Communication of Perioperative Information for Patients Undergoing Thyroid Cancer Surgery.” Summary: We present a field-by-field comparison of the ATA's essential elements as applied to three contemporary electronic reporting systems: the Thyroid Surgery e-Form from Memorial Sloan-Kettering Cancer Center (MSKCC), the Alberta WebSMR from the University of Calgary, and the Thyroid Cancer Care Collaborative (TCCC). The MSKCC e-form fulfills 21 of 32 intraoperative fields and includes an additional 14 fields not specifically mentioned in the ATA's report. The Alberta WebSMR fulfills 45 of 82 preoperative and intraoperative fields outlined by the ATA and includes 13 additional fields. The TCCC fulfills 117 of 120 fields outlined by the ATA and includes 23 additional fields. Conclusions: Effective management of thyroid cancer is a highly collaborative, multidisciplinary effort. The patient information that factors into clinical decisions about thyroid cancer is complex. For these reasons, EHRs are particularly favorable for the management of patients with thyroid cancer. The MSKCC Thyroid Surgery e-Form, the Alberta WebSMR, and the TCCC each meet all of the general recommendations for effective reporting of the specific domains that they cover in the management of thyroid cancer, as recommended by the ATA. However, the TCCC format is the most comprehensive. The TCCC is a new Web-based disease-specific database to enhance communication of patient information between clinicians in a Health Insurance Portability and Accountability Act (HIPAA)-compliant manner. We believe the easy-to-use TCCC format will enhance clinician communication while providing portability of thyroid cancer information for patients.
Supratherapeutic International Normalized Ratios in Warfarin-Treated Patients Who Receive a Highly Potentiating Antimicrobial Course