Comparing Multivisceral Resection with Tumor-only Resection of Liposarcoma Using the Win Ratio

BACKGROUND

Multivisceral resection of retroperitoneal liposarcoma (LPS) is associated with increased morbidity and may not confer a survival benefit compared with tumor-only (TO) resection. We compared both approaches using a novel statistical method called the "win ratio" (WR).

METHODS

Patients who underwent resection of LPS from 2004 to 2015 were identified from the National Cancer Database. Multivisceral resection was defined as removal of the primary site in addition to other organs. The WR was calculated based on a hierarchy of postoperative outcomes: 30-day and 90-day mortality, long-term survival, and severe complication.

RESULTS

Among 958 patients (multivisceral 634, TO 324) who underwent resection, the median age was 63 years (interquartile range [IQR] 54-71) with a median follow-up of 51 months (IQR 30-86). There was no difference in the WR among patients who underwent TO versus multivisceral resection in the matched cohort (WR 0.82, 95% confidence interval [CI] 0.61-1.10). In patients aged 72-90 years, those who underwent multivisceral resection had 36% lower odds of winning compared with patients undergoing TO resection (WR 0.64, 95% CI 0.40-0.98). A subgroup analysis of patients classified as not having adjacent tumor involvement at the time of surgery revealed that those patients who underwent multivisceral resection had 33% lower odds of winning compared to TO resection (WR 0.67, 95% CI 0.45-0.99).

CONCLUSIONS

Based on win-ratio assessments of a hierarchical composite endpoint, multivisceral resection in patients without adjacent tumor involvement may not confer improved outcomes. This method supports the rationale for less invasive resection of LPS in select patients, especially older patients.

Radiotherapy Dose as a Predictor of Outcomes Following Cardiac Radioablation for High-risk Refractory VT

PURPOSE/OBJECTIVE(S)

Cardiac radioablation (CRA) is an emerging treatment for high-risk refractory ventricular tachycardia (VT). Despite a fixed prescription dose to the planning target volume (PTV) there is still considerable heterogeneity in the radiotherapy dose distribution due to planning technique, proximity to organs at risk, and radiation oncologist preference. The hypothesis is that plans with an inherently "hotter" internal dose to the PTV may lead to improved VT outcomes.

MATERIALS/METHODS

Single-center, IRB-approved retrospective case series of patients with refractory VT who had failed at least one prior CA (or were unfit for CA) treated with CRA. All patients were treated with a single fraction of 25 Gy prescribed to the PTV. Maximum dose to PTV was collected from each plan and stratified as high vs low above and below the median. Maximum dose was defined as the highest dose delivered to the "hottest" 0.035 cc of the PTV to avoid known variability in reporting of dose to single voxels within the treatment planning system. Rates of survival (OS), freedom from shock and/or storm (FFSS), and freedom from death, shock, and/or storm (FFDSS) were collected, and stratified by maximum dose to the PTV. Formal statistical comparisons were not performed due to limited patient numbers.

RESULTS

From 2015-2020, 22 patients were treated with CRA (18 with prior CA, 4 unfit for CA) for high-risk refractory VT. Median age was 64.5 years (range, 49-84), and 90.9% were male. 50% had ICM, with a median NYHA class of 3 (range, 1-4) and median EF of 25% (range, 15-58%). Median follow-up was 31.3 months. 2-year OS was 54.5%, FFSS was 42.4%, and FFDSS was 27.3%. Median maximum dose to the PTV was 42.2 Gy (range, 29.2-45.8 Gy). PTV maximum dose (high vs low) discriminated 2-year OS (63.6% vs 45.5%), FFSS (50% vs 30%) and FFDSS (36.4% vs 18.2%). For all endpoints, Kaplan-Meier curves overlapped for the first 6 months, and then diverged.

CONCLUSION

In patients with high-risk refractory VT treated with CRA, survival and VT outcomes were similar between both groups out to 6 months, with improved OS and VT control noted after that with higher maximum doses. With a prescription dose of 25 Gy to the PTV, adjusting planning parameters to maintain maximum doses > 42 Gy may improve durable outcomes and requires validation in a larger cohort.

Culture-negative TB: clinical characteristics, risk factors and treatment outcomes

BACKGROUND: Although culture remains the standard for TB diagnosis, 15-20% of patients diagnosed and treated for TB are culture-negative. We explored clinical characteristics, risk factors and treatment outcomes for culture-negative TB in a Peruvian cohort.METHODS: We recruited 4,500 index TB patients and 10,160 household contacts in Lima, Peru, and enrolled 692 secondary patients diagnosed with TB during follow-up of household contacts. We analyzed smear and culture status, sociodemographic factors, clinical characteristics and TB treatment outcomes to compare culture-negative and positive patients.RESULTS: Of the 4,880 adult patients, 915 (18.8%) were culture-negative. Culture-negative patients were less likely to report symptoms of TB disease and disease of longer duration. A multivariate analysis showed no statistically significant difference in loss to follow-up, treatment failure or recurrence between the culture-negative and -positive groups but a higher rate of death among culture-negative patients with an adjusted OR of 1.65 (95% CI 1.05-2.60). In a multivariate analysis of determinants of culture negativity, older age, substance use and being a secondary case were associated with culture status.CONCLUSIONS: More recognition and awareness of culture-negative TB is key for early and correct diagnosis to reduce transmission and improve treatment outcomes.

Using digital chatbots to close gaps in healthcare access during the COVID-19 pandemic

INTRODUCTION

Chatbots have emerged as a first link to care in recent years. The COVID-19 pandemic, and consequent health system disruptions, expanded their use. Socios En Salud (SES) introduced chatbots in Peru, which experienced one of the highest excess COVID mortalities in the world.

METHODS

SES and the government identified unmet population health needs, which could be amenable to virtual interventions. Chatbots were developed to screen individuals for these conditions; we describe the period of deployment, number of screenings, and number of people who received services.

RESULTS

Between April 2020 and May 2021, SES deployed nine ChatBots: four for mental health, two for maternal and child health, and three for chronic diseases: breast cancer, hypertension, diabetes mellitus, and obesity. Mental health services were provided to 42,932 people, 99.99% of those offered services. The other ChatBots reached fewer people. Overall, more than 50% of eligible people accepted chatbot-based services.

DISCUSSION

ChatBot use was highest for mental health. Chatbots may increase connections between a vulnerable population and health services; this is likely dependent on several factors, including condition, population, and penetration of smart phones. Future research will be critical to understand user experience and preferences and to ensure that chatbots link vulnerable populations to appropriate, high-quality care.

The Role of AKT in Soft Tissue Sarcoma: Review and Insights

Soft tissue sarcomas (STS) are a biologically diverse group of mesenchymal tumors that predominantly exhibit a poor prognosis. Surgical resection is considered the mainstay of treatment and provides the only chance for long-term survival. However, some patients present with locally advanced, unresectable disease, and for those who are able to undergo resection, tumor recurrence occurs in over half of patients. In addition, the efficacy of conventional systemic therapies remains dismal. The serine/threonine kinase AKT pathway is one of the most frequently aberrant activated signaling pathways that has been verified in many types of human cancer. Dysregulation of the AKT cascade is known to result in tumorigenesis and aggressive clinical behavior for many tumor types including STS. Epidermal growth factor receptor (EGFR), with its downstream effectors, phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT)/mammalian target of rapamycin (mTOR), have been investigated for decades as promising targets for the treatment of STS, but significant challenges remain and the prognosis of patients with advanced STS has not improved in over two decades. In this review, we will first describe the AKT pathway and its role in STS tumor biology and then discuss the current challenges in targeting the AKT pathway to treat patients with advanced sarcoma.

Management of Transected Invasive Melanoma: A Single Institution Retrospective Review

BACKGROUND

Deep transection of invasive melanoma precludes accurate measurement of Breslow depth, which may affect tumor staging.

OBJECTIVE

To determine the frequency of upstaging of transected invasive melanomas after excision, characterize the impact on National Comprehensive Cancer Network (NCNN)-recommended treatment, and determine predictors of subsequent upstaging.

MATERIALS AND METHODS

A retrospective review of invasive melanomas between January 2017 and December 2019 at a single institution. Deeply transected biopsy reports were compared with subsequent excisions to calculate the frequency of upstaging.

RESULTS

Three hundred sixty (49.6%) of 726 invasive melanomas identified were transected. Forty-nine (13.6%) transected tumors had upstaging that would have altered NCCN-recommended management. "Broadly" transected tumors had upstaging that would have resulted in a change in the management in 5/23 cases (21.7%) versus 2/41 cases (4.9%) for "focally" transected tumors (p = .038). Breslow depth increased by 0.59 mm on average for "broad" transection versus 0.06 mm for "focal" transection (p =< .01). Of the 89 transected pT1a melanomas, specimens with gross residual tumor or pigment after biopsy were upstaged in 8/17 (47.1%) of cases versus 5/72 (6.9%) of specimens without (p =< .01).

CONCLUSION

Upstaging of deeply transected invasive melanomas that would alter NCCN-recommended management occurred in 13.6% of cases. Broad transection and gross residual tumor or pigment after biopsy predicted higher likelihood of upstaging.

Precision Nuclear Medicine: The Evolving Role of PET in Melanoma

The clinical management of melanoma patients has been rapidly evolving with the introduction of new targeted immuno-oncology (IO) therapeutics. The current diagnostic paradigms for melanoma patients begins with the histopathologic confirmation of melanoma, initial staging of disease burden with imaging and surgical approaches, treatment monitoring during systemic cytotoxic chemotherapy or IO therapeutics, restaging after completion of adjuvant systemic, surgical, and/or external radiation therapy, and the detection of recurrent malignancy/metastatic disease following therapy. New and evolving imaging approaches with positron-emission tomography (PET) imaging technologies, imaging methodologies, image reconstruction, and image analytics will likely continue to improve tumor detection, tumor characterization, and diagnostic confidence, enabling novel precision nuclear medicine practices for managing melanoma patients. This review will examine current concepts and challenges with existing PET imaging diagnostics for melanoma patients and introduce exciting new opportunities for PET in the current era of IO therapeutics.

Endoscopic spectrum and practical classification of small bowel gastrointestinal stromal tumors (GISTs) detected during double-balloon enteroscopy

Background and study aims  Information about the endoscopic characterization of small bowel gastrointestinal tumors (GISTs) is limited. The aim of this case study was to describe the endoscopic spectrum of small bowel GISTs and to present a practical classification. Patients and methods  Observational, retrospective, consecutive case series of patients with small bowel GIST. Results  A total of 10 small bowel GISTs were found in patients (6 male, 4 female, mean age 52 years, range 28 to 68).). All patients presented with obscure gastrointestinal bleeding (overt, n = 8, occult, n = 2). Most GISTs were present in the proximal or middle small bowel (n = 7). The endoscopic tumor characteristics could be categorized as follows: submucosal round (n = 4), submucosal sessile (n = 2), and invasive/penetrating) (n = 4). The mucosa overlying the tumor was normal (n = 4), grooved (n = 3) or frankly ulcerated (n = 3). Tumor size ranged from 8 mm to 50 mm. Biopsy was negative in all patients with normal mucosa but showed tumor in all patients with ulcerations. Regardless of biopsy results, all patients were sent for surgery. Nine resections were carried out. One patient refused surgery. There were no complications of endoscopy in this cohort. Conclusion  Our series shows that GISTs have a wider spectrum of endoscopic characteristics than previously described. The round type with normal overlying mucosa was equally prevalent as the grooved or ulcerated variant. Endoscopists should be aware of this wide spectrum of presentation of small bowel GIST.

NCCN Guidelines Insights: Uveal Melanoma, Version 1.2019

The NCCN Guidelines for Uveal Melanoma include recommendations for staging, treatment, and follow-up of patients diagnosed with uveal melanoma of the choroid or ciliary body. In addition, because distinguishing between uveal melanoma and benign uveal nevi is in some cases difficult, these guidelines also contain recommendations for workup of patients with suspicious pigmented uveal lesions, to clarify the tests needed to distinguish between those who should have further workup and treatment for uveal melanoma versus those with uncertain diagnosis and low risk who should to be followed and later reevaluated. These NCCN Guidelines Insights describe recommendations for treatment of newly diagnosed nonmetastatic uveal melanoma in patients who have already undergone a complete workup.

Characterization and validation of olive FAD and SAD gene families: expression analysis in different tissues and during fruit development

Stearoyl-ACP desaturases (SADs) and fatty acid desaturases (FADs) play a critical role in plant lipid metabolism and also affect oil fatty acid composition introducing double bonds into the hydrocarbon chains to produce unsaturated fatty acids. In the present study, the genomic sequences of three SAD and three FAD candidate genes were characterized in olive and their expression was evaluated in different plant tissues. OeSAD genes corresponded to olive SAD1 and SAD2 and to a newly identified OeSAD4, sharing the conserved protein structure with other plant species. On the other hand, the full-length genomic sequences of two microsomal OeFAD genes (FAD2-1 and FAD2-2) and the plastidial FAD6, were released. When the level of expression was tested on different tissues of cv. Leccino, OeSAD1 and OeSAD2 were mainly expressed in the fruits, while OeFAD genes showed the lowest expression in this tissue. The mRNA profiling of all genes was directly studied in fruits of Leccino and Coratina cultivars during fruit development. In both genotypes, the expression level of OeSAD1 and OeSAD2 had the highest value during and after the pit-hardening period, when oil accumulation in fruit mesocarp is intensively increasing. Furthermore, the expression level of both OeFAD2 genes, which were the main candidates for oleic acid desaturation, were almost negligible during fruit ripening. These results have made possible to define candidate genes of the machinery regulation of fatty acid composition in olive oil, providing information on their sequence, gene structure and chromosomal location.

Timed Stair-Climbing as a Surrogate Marker for Sarcopenia Measurements in Predicting Surgical Outcomes

BACKGROUND

Estimating sarcopenia by measuring psoas muscle density (PMD) has been advocated as a method to accurately predict post-operative morbidity. The aim of the present study was to determine whether the Timed Stair Climb (TSC) could be used to replace PMD measurements in predicting morbidity.

METHODS

Patients were prospectively enrolled from March 2014-2015 and were eligible if they were undergoing an abdominal operation. PMD was measured using pre-operative CT scans obtained within 90 days of surgery. Ninety-day complications were assessed using the Accordion Severity Grading System. Multivariable analysis was performed to identify risk factors associated with operative morbidity.

RESULTS

Of the patients, 298 were enrolled and completed TSC prior to undergoing an operation. Using the According Grading System, a grade 2 or higher complication occurred in 72 (24. 2%) patients with 8 (2.7%) deaths. There was an indirect relationship between PMD and TSC (P < 0.0001) and a direct relationship between TSC and complications (P = 0.04). On multivariable analysis decreasing PMD (P = 0.018) and increasing TSC (P = 0.026) were predictive of post-operative morbidity. Receiver operating characteristic curves demonstrated that the TSC was superior to both the ACS NSQIP Risk Calculator and PMD in predicting outcomes (TSC vs. PMD, P = 0.012; PMD vs. ACS NSQIP, P = 0.013; TSC vs. ACS NSQIP, P < 0.0001).

CONCLUSION

TSC, PMD, and the ACS NSQIP calculator are all useful tools; however, the TSC is superior in predicting post-operative morbidity.

Heterogeneity of Vascular Endothelial Cells, De Novo Arteriogenesis and Therapeutic Implications in Pancreatic Neuroendocrine Tumors

Arteriogenesis supplies oxygen and nutrients in the tumor microenvironment (TME), which may play an important role in tumor growth and metastasis. Pancreatic neuroendocrine tumors (pNETs) are the second most common pancreatic malignancy and are frequently metastatic on presentation. Nearly a third of pNETs secrete bioactive substances causing debilitating symptoms. Current treatment options for metastatic pNETs are limited. Importantly, these tumors are highly vascularized and heterogeneous neoplasms, in which the heterogeneity of vascular endothelial cells (ECs) and de novo arteriogenesis may be critical for their progression. Current anti-angiogenetic targeted treatments have not shown substantial clinical benefits, and they are poorly tolerated. This review article describes EC heterogeneity and heterogeneous tumor-associated ECs (TAECs) in the TME and emphasizes the concept of de novo arteriogenesis in the TME. The authors also emphasize the challenges of current antiangiogenic therapy in pNETs and discuss the potential of tumor arteriogenesis as a novel therapeutic target. Finally, the authors prospect the clinical potential of targeting the FoxO1-CD36-Notch pathway that is associated with both pNET progression and arteriogenesis and provide insights into the clinical implications of targeting plasticity of cancer stem cells (CSCs) and vascular niche, particularly the arteriolar niche within the TME in pNETs, which will also provide insights into other types of cancer, including breast cancer, lung cancer, and malignant melanoma.

Feasibility and yield of screening for non-communicable diseases among treated tuberculosis patients in Peru

INTRODUCTION

The increasing prevalence of non-communicable diseases (NCDs) poses a major challenge to low- and middle-income countries. Patients' engagement with health services for anti-tuberculosis treatment provides an opportunity for screening for NCDs and for linkage to care.

METHODS

We explored the feasibility and yield of screening for NCDs in patients treated for tuberculosis (TB) in Lima, Peru, as part of a study focused on chronic respiratory sequelae. A representative sample of community controls was recruited from the same geographical area. Screening entailed taking a medical history and performing ambulatory blood pressure measurement and urinalysis.

RESULTS

A total of 177 participants with previous TB (33 with multidrug-resistant TB) and 161 community controls were evaluated. There was an almost four-fold increased prevalence of self-reported diabetes mellitus (DM) in the TB group (adjusted prevalence ratio 3.66, 95%CI 1.68-8.01). Among those without self-reported DM, 3.3% had glycosuria, with a number needed to screen (NNS) of 31. The NNS to find one (new) case of hypertension or proteinuria in the TB group was respectively 24 and 5.

CONCLUSION

Patient-centred care that includes pragmatic NCD screening is feasible in TB patients, and the treatment period provides a good opportunity to link patients to ongoing care.

Predictive biomarkers for immune checkpoint blockade and opportunities for combination therapies

Immune checkpoint blockade therapies (ICBs) are a prominent breakthrough in cancer immunotherapy in recent years (named the 2013 “Breakthrough of the Year” by the Science magazine). Thus far, FDA-approved ICBs primarily target immune checkpoints CTLA-4, PD-1, and PD-L1. Notwithstanding their impressive long-term therapeutic benefits, their efficacy is limited to a small subset of cancer patients. In addition, ICBs induce inadvertent immune-related adverse events (irAEs) and can be costly for long-term use. To overcome these limitations, two strategies are actively being pursued: identification of predictive biomarkers for clinical response to ICBs and multi-pronged combination therapies. Biomarkers will allow clinicians to practice a precision medicine approach in ICBs (biomarker-based patient selection) such as treating triple-negative breast cancer patients that exhibit PD-L1 staining of tumor-infiltrating immune cells in ≥1% of the tumor area with nanoparticle albumin-bound (nab)–paclitaxel plus anti-PD-L1 and treating patients of MSI-H or MMR deficient unresectable or metastatic solid tumors with pembrolizumab (anti-PD-1). Importantly, the insights gained from these biomarker studies can guide rational combinatorial strategies such as CDK4/6 inhibitor/fractionated radiotherapy/HDACi in conjunction with ICBs to maximize therapeutic benefits. Further, with the rapid technological advents (e.g., ATCT-Seq), we predict more reliable biomarkers will be identified, which in turn will inspire more promising combination therapies.

Cutaneous Melanoma, Version 2.2019, NCCN Clinical Practice Guidelines in Oncology

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Cutaneous melanoma have been significantly revised over the past few years in response to emerging data on immune checkpoint inhibitor therapies and BRAF-targeted therapy. This article summarizes the data and rationale supporting extensive changes to the recommendations for systemic therapy as adjuvant treatment of resected disease and as treatment of unresectable or distant metastatic disease.

Gallbladder Cancer: Diagnosis, Surgical Management, and Adjuvant Therapies

Gallbladder cancer (GBC) is an often lethal disease, but surgical resection is potentially curative. Symptoms may be misdiagnosed as biliary colic; over half of new diagnoses are made after laparoscopic cholecystectomy for presumed benign disease. Gallbladder polyps >1 cm should prompt additional imaging and cholecystectomy. For GBC diagnosed after cholecystectomy, tumors T1b and greater necessitate radical cholecystectomy. Radical cholecystectomy includes staging laparoscopy, hepatic resection, and locoregional lymph node clearance to achieve R0 resection. Patients with locally advanced disease (T3 or T4), hepatic-sided T2 tumors, node positivity, or R1 resection may benefit from adjuvant chemotherapy. Chemotherapy increases survival in unresectable disease.

Community strengthening and mental health system linking after flooding in two informal human settlements in Peru: a model for small-scale disaster response

BACKGROUND

Mental health is an important factor in responding to natural disasters. Observations of unmet mental health needs motivated the subsequent development of a community-based mental health intervention following one such disaster affecting Peru in 2017.

METHODS

Two informal human settlements on the outskirts of Lima were selected for a mental health intervention that included: (1) screening for depression and domestic violence, (2) children's activities to strengthen social and emotional skills and diminish stress, (3) participatory theater activities to support conflict resolution and community resilience, and (4) community health worker (CHW) accompaniment to government health services.

RESULTS

A total of 129 people were screened across both conditions, of whom 12/116 (10%) presented with depression and 21/58 (36%) reported domestic violence. 27 unique individuals were identified with at least one problem. Thirteen people (48%) initially accepted CHW accompaniment to government-provided services.

CONCLUSIONS

This intervention provides a model for a small-scale response to disasters that can effectively and acceptably identify individuals in need of mental health services and link them to a health system that may otherwise remain inaccessible.

Barriers to the treatment of childhood tuberculous infection and tuberculosis disease: a qualitative study

SETTING

In 2012, Peru's National TB Program (NTP) reported approximately 2400 incident cases of tuberculosis (TB) disease in children aged <15 years. Peru's TB burden is concentrated in the Lima metropolitan area, particularly in poor districts such as El Agustino and La Victoria, where this study was conducted.

OBJECTIVE

To identify barriers to the treatment of childhood tuberculous infection and TB disease in Lima from the perspective of front-line providers and patients' families.

DESIGN

We conducted 10 semi-structured focus groups with 53 purposefully sampled primary care providers, community health workers, and parents/guardians of pediatric TB patients. We also completed nine in-depth interviews with National TB Program administrators and pulmonologists specializing in TB. Two authors performed inductive thematic analysis and identified emerging themes.

RESULTS

Four main treatment barriers emerged from the data: 1) dosing errors, 2) time- and labor-intensive preparation and administration of medications, 3) provider concern that isoniazid preventive therapy (IPT) generates isoniazid resistance, and 4) poor adherence to IPT.

CONCLUSION

Our findings highlight the urgent need for child-friendly formulations, provider and parent/guardian education about IPT, and strategies to promote adherence to IPT, including support and supervision by health workers and/or regimens with fewer doses.

Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis

On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.

Electromagnetic evidence that SSS17a is the result of a binary neutron star merger

Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result.

Abstract B14: TP53 synthetic lethal targets in colon cancer

We have performed a genome-wide screen for pathways that are synthetic lethal with TP53 mutations in colon cancer. RKO colon cancer cells are wild type for TP53, and display robust p53-dependent growth arrest and apoptosis. We utilized an isogenic pair of RKO cells differing only in TP53 gene status (wild type vs homozygous null derivative) to screen a genome-wide GeCKO CRISPR library. After infection of these cells with the library and culturing for one week in vitro, we performed deep amplicon sequencing to identify CRISPR guide RNAs that were underrepresented in TP53 knockout cells. Multiple CRISPR guide RNAs targeting the CHEK1 and SHH genes were underrepresented in TP53 knockout cells. To validate these targets, we used CRISPR genome engineering to create an independent panel of six RKO clones with biallelic disruption of TP53, and tested small molecule inhibitors of CHEK1 (UCN01) and the SHH receptor SMO (Cyclopamine). TP53 null cells were tenfold more sensitive to UCN01, and 100-fold more sensitive to Cyclopamine, compared to TP53 wild type cells. Finally, the relevance of these findings to human colon cancers was confirmed by the establishment and treatment of colon cancer organoid avatars with either wild type or mutant TP53. Normal colon organoids, and tumor organoids with wild type TP53 were unaffected by either drug, whereas TP53 mutant organoids were significantly growth inhibited. Future studies will focus on testing these and additional targets, alone and in combination, against primary colon tumor and normal avatars and other preclinical models of TP53-mutant colon cancer.

Citation Format: Charles C. Weige, Changlong Liu, Erin L. Anderson, Carolyn E. Banister, Joseph Richardson, Carlo Contreras, Phillip J. Buckhaults. TP53 synthetic lethal targets in colon cancer. [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer: From Initiation to Outcomes; 2016 Sep 17-20; Tampa, FL. Philadelphia (PA): AACR; Cancer Res 2017;77(3 Suppl):Abstract nr B14.

Abstract B10: Synthetic lethal screen to identify novel therapies targeting TP53-mutant colon cancer cells

We have performed a genome-wide synthetic lethal screen for pathways that are essential for the survival of colon cancer cells with TP53 mutations. RKO colon cancer cells are wild-type for TP53, and display robust p53-dependent growth arrest and apoptosis. We have utilized an isogenic pair of RKO cells differing only in TP53 gene status (Wild Type vs homozygous null derivative) to screen a genome-wide GeCKO CRISPR library and identified pathways that are novel therapeutic targets for TP53-mutant colon cancers. After infection of these cells with the GeCKO CRISPR library and one week of culturing in vitro, we performed deep GeCKO CRIPSR amplicon sequencing to enumerate and identify all CRISPRs that were underrepresented in TP53 mutant compared to wild type cells. We identified multiple CRISPRs targeting the CHEK1 and the SHH genes which were underrepresented in TP53 knockout cells. We then tested small molecule inhibitors of CHEK1 (UCN01) and the SHH receptor SMO (Cyclopamine) against isogenic pairs of RKO, HCT116, and DLD1 cells and confirmed that each molecule is significantly more toxic to cells with mutant TP53 than to those with wild-type TP53. Future studies will focus on testing these and additional targets alone and in combination against primary colon tumor and normal avatars, and preclinical models of TP53-mutant colon cancer.

Citation Format: Charles C. Weige, Erin L. Anderson, Joseph Richardson, Carlo Contreras, Phillip J. Buckhaults. Synthetic lethal screen to identify novel therapies targeting TP53-mutant colon cancer cells. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Targeting the Vulnerabilities of Cancer; May 16-19, 2016; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(1_Suppl):Abstract nr B10.

Barriers to the diagnosis of childhood tuberculosis: a qualitative study

SETTING

In 2012, Peru's National Tuberculosis Program (NTP) reported that children aged 0-14 years accounted for 7.9% of the country's tuberculosis (TB) incidence. This figure is likely an underestimate due to suboptimal diagnosis of childhood TB.

OBJECTIVE

To identify barriers to childhood TB diagnosis in Lima, Peru.

DESIGN

Using semi-structured guides, moderators conducted in-depth interviews with four NTP administrators and five pulmonologists specializing in TB and 10 focus groups with 53 primary care providers, community health workers (CHWs), and parents and/or guardians of pediatric TB patients. Two authors independently performed inductive thematic analysis and identified emerging themes.

RESULTS

Participants identified five barriers to childhood TB diagnosis: ignorance and stigma among the community, insufficient contact investigation, limited access to diagnostic tests, inadequately trained health center staff, and provider shortages.

CONCLUSION

Recent efforts to increase childhood TB detection have centered on the development of new technologies. However, our findings demonstrate that many diagnostic barriers are rooted in socio-economic and health system problems. Potential solutions include implementing multimedia campaigns and community education to reduce ignorance and stigma, prioritizing contact investigation for high-risk households, and training primary care providers and CHWs to recognize and evaluate childhood TB.

Pancreatic cancer survivors' preferences, barriers, and facilitators related to physical activity and diet interventions

PURPOSE

To conduct a telephone survey establishing pancreatic cancer survivors' level of interest in, preferences for, and perceived barriers and facilitators to participating in exercise and diet intervention programming. These data will inform the development of such interventions for newly-diagnosed patients.

METHODS

Seventy-one survivors treated for resectable pancreatic adenocarcinoma from October 2011 to August 2014 were identified through an institutional cancer registry and contacted via telephone. A telephone survey was conducted to query survivors' level of interest in, preferences for, and perceived barriers and facilitators to participating in an exercise and dietary intervention program shortly after disease diagnosis. Acceptability of a technology-based visual communication (e.g., Skype™, FaceTime®) intervention was also assessed.

RESULTS

Fifty participants completed the survey (response rate 71.8 %). Over two-thirds of participants reported interest in exercise and diet intervention programming. Over half reported comfort with a technology-delivered visual communication intervention. Barriers to participation included older age and physical, personal, and emotional problems. The most common facilitator was program awareness. Outcomes for future research important to participants were supportive care and quality of life.

CONCLUSIONS

Most pancreatic cancer patients are interested in exercise and diet interventions shortly after diagnosis; however, some barriers to program participation exist.

IMPLICATIONS FOR CANCER SURVIVORS

Future research and intervention planning for pancreatic cancer survivors should focus on developing messaging and strategies that provide support for survivorship outcomes, increase survivor awareness, address lack of familiarity with technology, reduce fears about potential barriers, and help survivors overcome these barriers. In so doing, survivorship needs can be better met and quality of life improved in this understudied population.

Effects of neonatal programming on hypothalamic mechanisms controlling energy balance

The prevalence of overweight and obesity in most developed countries has markedly increased during the last decades. In addition to genetic, hormonal, and metabolic influences, environmental factors like fetal and neonatal nutrition play key roles in the development of obesity. Interestingly, overweight during critical developmental periods of fetal and/or neonatal life has been demonstrated to increase the risk of obesity throughout juvenile life into adulthood. In spite of this evidence, the specific mechanisms underlying this fetal/neonatal programming are not perfectly understood. However, it is clear that circulating hormones such as insulin and leptin play a critical role in the development and programming of hypothalamic circuits regulating energy balance. Here, we review what is currently known about the impact of perinatal malnutrition on the mechanisms regulating body weight homeostasis. Understanding these molecular mechanisms may provide new targets for the treatment of obesity.

Clinical characteristics, drug resistance, and treatment outcomes among tuberculosis patients with diabetes in Peru

OBJECTIVES

Diabetes is a risk factor for active tuberculosis (TB). Data are limited regarding the association between diabetes and TB drug resistance and treatment outcomes. We examined characteristics of TB patients with and without diabetes in a Peruvian cohort at high risk for drug-resistant TB. Among TB patients with diabetes (TB-DM), we studied the association between diabetes clinical/management characteristics and TB drug resistance and treatment outcomes.

METHODS

During 2005-2008, adults with suspected TB with respiratory symptoms in Lima, Peru, who received rapid drug susceptibility testing (DST), were prospectively enrolled and followed during treatment. Bivariate and Kaplan-Meier analyses were used to examine the relationships of diabetes characteristics with drug-resistant TB and TB outcomes.

RESULTS

Of 1671 adult TB patients enrolled, 186 (11.1%) had diabetes. TB-DM patients were significantly more likely than TB patients without diabetes to be older, have had no previous TB treatment, and to have a body mass index (BMI) >18.5 kg/m(2) (p<0.05). In patients without and with previous TB treatment, the prevalence of multidrug-resistant TB was 23% and 26%, respectively, among patients without diabetes, and 12% and 28%, respectively, among TB-DM patients. Among 149 TB-DM patients with DST results, 104 (69.8%) had drug-susceptible TB and 45 (30.2%) had drug-resistant TB, of whom 29 had multidrug-resistant TB. There was no association between diabetes characteristics and drug-resistant TB. Of 136 TB-DM patients with outcome information, 107 (78.7%) had a favorable TB outcome; active diabetes management was associated with a favorable outcome.

CONCLUSIONS

Diabetes was common in a cohort of TB patients at high risk for drug-resistant TB. Despite prevalent multidrug-resistant TB among TB-DM patients, the majority had a favorable TB treatment outcome.

Alternative strategy to decrease cesarean section: support by doulas during labor

This research was conducted in a public general hospital in Mexico City, Mexico. The objective was to evaluate efficacy of the support given by a doula during labor to reduce cesarean rate. From March 1997 to February 1998, a group of 100 pregnant women were studied. These women were at term, engaged in an active phase of labor, exhibited 3 cm. or more cervical dilatation, were nuliparous, had no previous uterine incision, and possessed adequate pelvises. The group was randomly divided into two subgroups comprising 50 women, each: The first subgroup had the support of a childbirth educator trained as a doula, while the second subgroup did not have doula support. Measurements were recorded on the duration of labor, the use of pitocin, and whether or not the birth was a vaginal birth or cesarean section. Characteristics and gestational age were similar in both groups. Results confirmed that support by doulas during labor was associated with a significant reduction in cesarean birth and pitocin administration. There was a trend toward shorter labors and less use of epidurals. The results of this study showed, as in other trials measuring the impact of a doula's presence during labor and birth, that doula support during labor is associated with positive outcomes that have physical, emotional, and economic implications.

Radiographic and clinical factors associated with improved outcomes in advanced cancer patients with bowel obstruction

BACKGROUND

The purpose of this study was to identify preoperative clinical and radiographic factors relevant to treatment selection and outcomes in patients with advanced cancer presenting with bowel obstruction.

METHODS

Clinical and radiographic data were retrospectively obtained from records of inpatients with suspected bowel obstruction referred for palliative surgical consultation (2000-2006). Patients were stratified according to site of obstruction: gastric outlet obstruction (GOO), small bowel obstruction (SBO), and large bowel obstruction (LBO). We utilized the Cox proportional hazards model to identify preoperative clinical and radiologic variables associated with overall survival (OS).

RESULTS

Of 191 patients, the site of obstruction was classified as GOO in 41 (21%), SBO in 122 (64%), and LBO in 28 (15%). Almost half of the patients (47%) had received systemic therapy in the 6 weeks prior to evaluation. The most common sites of disease identified on imaging included abdominal visceral metastases (37%), carcinomatosis/sarcomatosis (46%), and an intact primary tumor or recurrence (31%). Most patients (62%) exhibited 2 or more sites of disease on imaging. Treatment strategies included nonoperative/nonprocedural management in 41% (n = 79), endoscopic/interventional radiology procedures in 25% (n = 48), and surgery in 34% (n = 64). Median OS for the cohort was 3.5 months (95% confidence interval [CI]: 2.7-4.6). Median OS for GOO, SBO, and LBO was 2.7 (95% CI: 1.7-4.1), 3.5 (95% CI: 2.5-4.9), and 7.0 (95% CI: 2.1-11) months, respectively (p = 0.17). Adverse prognostic factors for OS included endoscopic/interventional radiology procedures and ≥3 radiologically evident sites of disease.

CONCLUSIONS

OS, although low, was not significantly different among GOO, SBO, and LBO. Single sites of disease identified on imaging were not associated with OS, although multiple sites of disease were associated with diminished OS.

Predicting mortality in hospitalized patients with 2009 H1N1 influenza pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) severity scores can identify patients at low risk for mortality who may be suitable for ambulatory care. Here, we follow the clinical course of hospitalized patients with CAP due to 2009 H1N1 influenza.

OBJECTIVE

To evaluate the role of CAP severity scores as predictors of mortality.

METHODS

This was a secondary data analysis of patients hospitalized with CAP due to 2009 H1N1 influenza confirmed by reverse transcriptase polymerase chain reaction enrolled in the CAPO (Community-Acquired Pneumonia Organization) international cohort study. CAP severity scores PSI (Pneumonia Severity Index), CURB-65 (confusion, urea, respiratory rate, blood pressure, age ≥ 65 years) and CRB-65 (confusion, respiratory rate, blood pressure, age ≥ 65 years) were calculated. Actual and predicted mortality rates were compared. A total of 37 predictor variables were evaluated to define those associated with mortality.

RESULTS

Data from 250 patients with CAP due to 2009 H1N1 influenza were analyzed. Patients with low predicted mortality rates (0-1.5%) had actual mortality rates ranging from 2.6% to 17.5%. Obesity and wheezing were the only novel variables associated with mortality.

CONCLUSIONS

The decision to hospitalize a patient with CAP due to 2009 H1N1 influenza should not be based on current CAP severity scores, as they underestimate mortality rates in a significant number of patients. Patients with obesity or wheezing should be considered at an increased risk for mortality.

Influenza pneumonia: a comparison between seasonal influenza virus and the H1N1 pandemic

We compared clinical presentation, complications and outcome in patients with influenza A (H1N1) and seasonal influenza pneumonia. The group of patients with influenza A (H1N1) pneumonia consisted of 75 patients. 52 patients with pneumonia associated with seasonal influenza were included for comparison. Patients with pneumonia associated with novel H1N1 influenza were younger (mean age 39.7 yrs versus 69.6 yrs) and had fewer chronic comorbidities and less alcoholism. Infiltrates were more extensive and frequently interstitial. Respiratory failure was more frequent (those with an arterial oxygen tension/inspiratory oxygen fraction ratio <200 28% versus 12%, p = 0.042), leading to a higher rate of intensive care unit (ICU) admission and mechanical ventilation (29.3% versus 7.7% (p<0.0030) and 18.7% versus 2% (p<0.0045)). Mortality was twice as high in patients with novel H1N1 (12% versus 5.8%; p = 0.238), although this was not significant, and was attributable to pneumonia in most instances (77.8% versus 0%; p = 0.046). Younger age, fewer comorbidities, more extensive radiographic extension and more severe respiratory compromise, and ICU admissions are key features of the clinical presentation of patients with novel H1N1-associated pneumonia compared with seasonal influenza pneumonia.

Electronic laboratory system reduces errors in National Tuberculosis Program: a cluster randomized controlled trial

OBJECTIVE

To evaluate the impact of the e-Chasqui laboratory information system in reducing reporting errors compared to the current paper system.

DESIGN

Cluster randomized controlled trial in 76 health centers (HCs) between 2004 and 2008.

METHODS

Baseline data were collected every 4 months for 12 months. HCs were then randomly assigned to intervention (e-Chasqui) or control (paper). Further data were collected for the same months the following year. Comparisons were made between intervention and control HCs, and before and after the intervention.

RESULTS

Intervention HCs had respectively 82% and 87% fewer errors in reporting results for drug susceptibility tests (2.1% vs. 11.9%, P = 0.001, OR 0.17, 95%CI 0.09-0.31) and cultures (2.0% vs. 15.1%, P < 0.001, OR 0.13, 95%CI 0.07-0.24), than control HCs. Preventing missing results through online viewing accounted for at least 72% of all errors. e-Chasqui users sent on average three electronic error reports per week to the laboratories.

CONCLUSIONS

e-Chasqui reduced the number of missing laboratory results at point-of-care health centers. Clinical users confirmed viewing electronic results not available on paper. Reporting errors to the laboratory using e-Chasqui promoted continuous quality improvement. The e-Chasqui laboratory information system is an important part of laboratory infrastructure improvements to support multidrug-resistant tuberculosis care in Peru.

Characteristics of hospitalised patients with 2009 H1N1 influenza in Chile

As the pandemic of 2009 H1N1 influenza A virus progressed, more patients required hospitalisation. The objective of this study is to describe the characteristics and clinical course of hospitalised patients with 2009 H1N1 virus infection in Chile. This was a prospective, observational study of 100 consecutive hospitalised patients with RT-PCR-confirmed 2009 H1N1 influenza A, admitted to Puerto Montt General Hospital (Puerto Montt, Chile). Information was obtained regarding contact history, demographics, laboratory values and clinical course. The primary reason for hospitalisation was pneumonia, in 75% of patients. Rapid influenza A test was positive in 51% of patients. Prior exposure to 2009 H1N1 virus was documented in 21% of patients. Clinical failure, documented in 18% of cases, was characterised by respiratory failure and acute respiratory distress syndrome. Failure was more common in patients with obesity, tachypnoea, confusion and multilobar infiltrates. When evaluating a patient hospitalised with influenza-like illness, a negative rapid test for influenza A or negative contact with a suspected case should not alter physicians' considerations regarding the likelihood of 2009 H1N1 virus infection. Patients with 2009 H1N1 virus infection with obesity, tachypnoea, confusion and multilobar infiltrates should be closely monitored since they are at high risk for clinical failure.

Altered arachidonic acid metabolism via COX-1 and COX-2 contributes to the endothelial dysfunction of penile arteries from obese Zucker rats

BACKGROUND AND PURPOSE

The aim of the current study was to investigate the role of arachidonic acid (AA) metabolism via cyclooxygenase (COX) in the endothelial dysfunction of penile arteries from pre-diabetic, obese Zucker rats (OZR).

EXPERIMENTAL APPROACH

Penile arteries from OZR and from lean Zucker rats (LZR) were mounted in microvascular myographs to assess vascular function and COX expression was determined by immunohistochemistry.

KEY RESULTS

Acetylcholine (ACh) and AA elicited relaxations that were impaired in arteries from OZR. Inhibition of both COX-1 and COX-2 reduced the relaxant effects of ACh and AA in LZR but not in OZR. Inhibitors of COX-1 and of the TXA(2)/PGH(2) (TP) receptor enhanced the relaxations induced by AA in both LZR and OZR, whereas COX-2 inhibition enhanced these responses only in OZR. TP receptor blockade did not restore ACh relaxant responses in arteries from OZR. Inhibition of COX-1 increased basal tension in OZR and this contraction was blunted by TP receptor blockade. The vasoconstrictor responses to noradrenaline were augmented by indomethacin and by COX-2 inhibition in LZR but not in OZR. Immunohistochemical staining showed that both COX-1 and COX-2 are expressed in the endothelium of penile arteries from both LZR and OZR.

CONCLUSIONS AND IMPLICATIONS

Vasoactive prostanoids were formed via constitutively active COX-1 and COX-2 pathways in normal rat penile arteries. Under conditions of insulin resistance, the release and/or effects of vasodilator prostanoids were impaired, contributing to the blunted endothelium-dependent vasodilatation and to the enhanced vasoconstriction.