Patterns of Care and Outcomes for Small Cell Carcinoma of the Cervix: A National Retrospective Analysis of 542 Cases.

PURPOSE: Small cell carcinoma of the cervix (SCCC) represents 1% to 5% of cervical cancers, with limited data on management and outcomes. We evaluated patterns of care and outcomes for SCCC using the National Cancer Database. METHODS AND MATERIALS: This retrospective cohort study of SCCC (2004-2011) included 542 cases. Patient demographic, diagnosis, treatment information, and overall survival (OS) were compared with descriptive statistics, logistic regression, Kaplan-Meier, and Cox models. Clinical reasoning was used to select variables for multivariable models to avoid overfitting. RESULTS: SCCC had more comorbidities, higher grade, and advanced stage than other histologies. SCCC received neoadjuvant chemotherapy (36%) more often than squamous cell carcinoma (23%) and adenocarcinoma (13%, P < .001). SCCC had worse OS across all stages (P < .001). Looking at SCCC alone, patients who received chemoradiation (CRT) (with external beam and brachytherapy) and those who received chemotherapy and surgery (without RT) had similar OS (median OS 44 vs 47 months; P = .7) on Kaplan-Meier. Patients receiving CRT were more likely to have stage II or III and N+ disease (P < .001). When evaluating chemoradiation, the addition of brachytherapy resulted in improved median OS (35 vs 19 months; P = .001) regardless of surgical resection status and controlling for age and stage. Even after controlling for stage, age, and comorbidities, the addition of brachytherapy was associated with a 40% improvement in OS (hazard ratio 1.4, 95% confidence interval 1.0-2.0). CONCLUSIONS: SCCC patients benefit from chemotherapy with aggressive local treatment. Patients who receive CRT that included brachytherapy did as well as patients who received chemotherapy followed by surgery. Brachytherapy remains an essential component in the treatment of SCCC with CRT.

Longitudinal Radiographic Outcomes of Vestibular Schwannoma in Single and Fractionated Stereotactic Radiosurgery: A Retrospective Cohort Study.

Management of vestibular schwannoma (VS) includes stereotactic radiosurgery (SRS) in single or fractionated treatments. There is a paucity of literature on the three-dimensional (3D) volumetric kinetics and radiological changes following SRS and no consensus on appropriate post-SRS surveillance imaging timeline. This is a retrospective cohort study with institutional review board approval. A total of 55 patients met study criteria. We collected volumetric kinetic data in VS treated with SRS over time using a target volume contouring software. We also tracked radiographic phenomena such as pseudoprogression and necrosis. A secondary objective was to describe our overall treatment success rate and any failures. For all treatments groups, pseudoprogression most typically occurred within 12 months post-SRS, after which tumor volumes on average normalized and then decreased from pretreatment size at the last follow-up. Only two patients required salvage therapy post-SRS and were considered SRS treatment failures. Both patients were in the five-fraction cohort but with a lower biologically equivalent dose. Our study is first to collect 3D volumetric kinetics of VS following single and fractionated SRS in contrast to extrapolations from single and two-dimensional measurements. Our longitudinal data also show initial increases in volume in the first 12 months post-SRS followed by later declines, setting up interesting questions regarding the utility of early posttreatment surveillance imaging in the asymptomatic patient. Finally, we show low rates of treatment failure (3.6%) and show in our cohort that SRS dose de-escalation posed a risk of treatment failure.

Correction: Using financial incentives to promote physical activity in American Indian adolescents: A randomized controlled trial.

[This corrects the article DOI: 10.1371/journal.pone.0198390.].

Current Volumetric Models Overestimate Vestibular Schwannoma Size Following Stereotactic Radiosurgery.

OBJECTIVE: Accurate volume assessment is essential for the management of vestibular schwannoma after stereotactic radiosurgery (SRS). A cuboidal approximation for volume is the standard surveillance method; however, this may overestimate tumor volume. We sought to evaluate several volumetric models and their suitability for post-SRS surveillance. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary referral center. PATIENTS: We evaluated 54 patients with vestibular schwannoma before and after SRS. INTERVENTION(S): Gold-standard volumes were obtained by a radiation oncologist using contouring software. Volume was also calculated by cuboidal, ellipsoidal, and spherical formulae using tumor diameters obtained by a neuroradiologist. MAIN OUTCOME MEASURE(S): Percent error (PE) and absolute percent error (APE) were calculated. Paired t test evaluated bias, and the Bland-Altman method evaluated reproducibility. Linear regression evaluated predictors of model error. RESULTS: All models overestimated volume compared with the gold standard. The cuboidal model was not reproducible before SRS (p < 0.001), and no model was reproducible after SRS (cuboidal p < 0.001; ellipsoidal p = 0.02; spherical p = 0.02). Significant bias was present before SRS for the cuboidal model (p < 0.001), and post-SRS for all models [cuboidal (p < 0.001), ellipsoidal (p < 0.02), and spherical (p = 0.005)]. Model error was negatively associated with pretreatment volume for the cuboidal (PE p = 0.03; APE p = 0.03), ellipsoidal (PE p = 0.03; APE p = 0.04), and spherical (PE p = 0.02; APE p = 0.03) methods and lost linearity post-SRS. CONCLUSIONS: The standard cuboidal practice for following vestibular schwannoma tumor volume after SRS overestimates size. Ellipsoidal and spherical estimations have improved performance but also overestimate volume and lack reliability post-SRS. The development of other volumetric models or application of contouring software should be investigated.

Racial Misclassification in Mortality Records Among American Indians/Alaska Natives in Oklahoma From 1991 to 2015.

OBJECTIVE: The primary purpose of this study was to compare age-adjusted mortality rates before and after linkage with Indian Health Service records, adjusting for racial misclassification. We focused on differences in racial misclassification by gender, age, geographic differences, substate planning districts, and cause of death. Our secondary purpose was to evaluate time trends in misclassification from 1991 to 2015. DESIGN: Retrospective, descriptive study. SETTING: Oklahoma. PARTICIPANTS: Persons contained in the Oklahoma State Health Department Vital Records. MAIN OUTCOME MEASURES: To evaluate the age-adjusted mortality ratio pre- and post-Indian Health Service record linkage (misclassification rate ratio) and to evaluate the overall trend of racial misclassification on mortality records measured through annual percent change (APC) and average annual percent change (AAPC). RESULTS: We identified 2 stable trends of racial misclassification upon death for American Indians/Alaska Natives (AI/ANs) from 1991 to 2001 (APC: -0.2%; 95% confidence interval: -1.4% to 1.0%) and from 2001 to 2005 (APC: -6.9%; 95% confidence interval: -13.7% to 0.4%). However, the trend identified from 2005 to 2015 decreased significantly (APC: -1.4%; 95% confidence interval: -2.5% to -0.2%). For the last 5 years available (2011-2015), the racial misclassification adjustment resulted in higher mortality rates for AI/ANs reflecting an increase from 1008 per 100 000 to 1305 per 100 000 with the linkage process. There were an estimated 3939 AI/ANs in Oklahoma who were misclassified as another race upon death in those 5 years, resulting in an underestimation of actual AI/AN deaths by nearly 29%. CONCLUSIONS: An important result of this study is that misclassification is improving; however, this effort needs to be maintained and further improved. Continued linkage efforts and public access to linked data are essential throughout the United States to better understand the burden of disease in the AI/AN population.

A Retrospective Cohort Study of Longitudinal Audiologic Assessment in Single and Fractionated Stereotactic Radiosurgery for Vestibular Schwannoma.

BACKGROUND: Fractionated stereotactic radiosurgery (SRS) for vestibular schwannomas (VS) has been theorized to allow for tumor control with higher rates of hearing preservation in selected patients with useful hearing. However, there is a paucity of literature with formal audiologic measures of hearing preservation to support the standard use of fractionated SRS in VS. We hypothesized that fractionation would diminish the amount of hearing damage. OBJECTIVE: To evaluate the relationship between audiologic performance and SRS fractionation scheme. METHODS: We performed an IRB-approved retrospective review of patients treated with 1, 3, or 5 fraction SRS for VS at our institution from 1998 to 2016. Pre- and post-SRS audiograms with speech awareness threshold (SAT) in treated and contralateral ears were obtained. Contralateral ear measurements were used for hearing normalization to account for presbycusis. RESULTS: Fifty-six patients with median audiologic follow-up 2.0 yr (mean 2.66 yr, min-max 0.50-9.45 yr) were included. Patients treated with single fractionation had a significantly worsened SAT (dB) compared to patients treated with 5 fractions (P = .008) and compared to all multifraction patients (P = .009) at 12 to 24 mo follow-up. CONCLUSION: This retrospective analysis supports the use of fractionated SRS to preserve hearing in patients with VS. SAT can be used as an objective metric of hearing response to radiosurgery.

Genomic Research and American Indian Tribal Communities in Oklahoma: Learning From Past Research Misconduct and Building Future Trusting Partnerships.

Research misconduct and consequential harms have been inflicted upon American Indian/Alaska Native communities for decades. To protect their people and culture and to retain oversight over research, many Native communities have established tribal health research and institutional review boards. The Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) Study showcases a successful, trusting research collaboration with tribal nations and academic investigators in Oklahoma. In 2006, the TODAY Study investigators proposed a modification of the study protocol to collect biological specimens from participants for genomic analyses and indefinite storage. Partnering American Indian tribal nations elected not to participate in the genomics collection and repository proposal. Reasons included 1) protection of cultural values, 2) concerns regarding community anonymity, 3) a potential threat to tribal services eligibility, 4) broad informed consent language, and 5) vague definitions of data access and usage. The nations believed the proposed genomics analyses presented a risk of harm to their people and nations without clear benefit. Since the 2006 proposal and the advancement of genomics research, many tribal communities in Oklahoma, appreciating the potential benefits of genomic research, are developing policies regarding oversight of/access to data and biological specimens to mitigate risks and provide members and communities with opportunities to participate in safe and meaningful genomic research.

Collaborative implementation of a community-based exercise intervention with a partnering rural American Indian community.

BACKGROUND: The prevalence and socioeconomic burden of childhood obesity and diabetes has increased rapidly in the United States in the last 30 years. American Indians have the highest prevalence of type 2 diabetes among newly diagnosed youth in the country. Contributing factors include environmental, behavioral, and genetic components. Some American Indian tribal communities have explored innovative ways to combat this epidemic including collaborations with academic centers on community-based research. METHOD: From 2012 to 2017, the University of Oklahoma Health Science Center and the Choctaw Nation of Oklahoma partnered on a National Institutes of Health-funded project to determine if financial incentives would elicit an increase in physical activity in Native youth. This was a community-based behavioral intervention for overweight or obese American Indian youth ages 11-20 living in a rural community at risk for developing diabetes. RESULTS: Tribal leaders and staff identified culturally appropriate strategies to aid implementation of the trial in their community. Their identified implementation strategies helped standardize the study in order to maintain study integrity. The mutually agreed strategies included co-review of the study by tribal and University research review boards (but designation of the Choctaw Nation review board as the "Board of Record"), training of community-based staff on research ethics and literacy, standardization of the informed consent process by videotaping all study information, creation of a viable and culturally appropriate timeline for study implementation, adapting tribal wellness center operations to accommodate youth, and development of effective two-way communication through training sessions, on-site coordination, and bi-monthly conference calls. CONCLUSION: In an effort to partner collectively on a randomized clinical research trial to combat childhood diabetes, tribal leaders and staff implemented strategies that resulted in a culturally appropriate and organized community-based behavioral intervention research project.

Using financial incentives to promote physical activity in American Indian adolescents: A randomized controlled trial.

American Indians (AI) have high prevalence of diabetes in youth and may benefit from increasing physical activity as a strategy to improve metabolic health. We tested whether financial incentives would elicit greater frequency and/or duration of exercise in AI youth at high risk for developing diabetes. Overweight/obese AI boys and girls, 11-20 years old, were instructed to exercise on 3 days/week for 48 weeks at a tribal wellness center. The program was divided into three, 16-week-long phases to test different financial incentive strategies. Within each phase participants were randomly assigned to one of two groups that received different payments for exercise. Phase 1 was designed to test whether the size of the incentive would affect exercise frequency. In Phase 1, the number of exercise sessions did not differ between the group receiving a modest fixed-value payment per exercise session and the group receiving enhanced incentives to exercise more frequently (26 ± 3 versus 28 ± 2 sessions, respectively, p = 0.568). In Phase 2, the provision of an enhanced financial incentive to increase exercise duration resulted longer sessions, as the incentivized and standard payment groups exercised 38 ± 2 versus 29 ± 1 minutes per session (p = 0.002), respectively. In Phase 3, the effect of reducing the incentives on maintenance of exercise behaviors was inconclusive due to high participant withdrawal. Aerobic fitness increased 10% during Phase 1 but was unchanged thereafter. Insulin sensitivity and body composition were unchanged during the study. In conclusion, enhanced financial incentives increased the duration of exercise sessions, but had minimal effects on exercise participation. These results indicate that financial incentives hold promise in motivating previously sedentary, overweight/obese adolescents to exercise longer, but motivating them to sustain an exercise program remains the major challenge. TRIAL REGISTRATION: ClinicalTrials.gov NCT01848353.

Impairment of memory generalization in preclinical autosomal dominant Alzheimer's disease mutation carriers.

Fast, inexpensive, and noninvasive identification of Alzheimer's disease (AD) before clinical symptoms emerge would augment our ability to intervene early in the disease. Individuals with fully penetrant genetic mutations causing autosomal dominant Alzheimer's disease (ADAD) are essentially certain to develop the disease, providing a unique opportunity to examine biomarkers during the preclinical stage. Using a generalization task that has previously shown to be sensitive to medial temporal lobe pathology, we compared preclinical individuals carrying ADAD mutations to noncarrying kin to determine whether generalization (the ability to transfer previous learning to novel but familiar recombinations) is vulnerable early, before overt cognitive decline. As predicted, results revealed that preclinical ADAD mutation carriers made significantly more errors during generalization than noncarrying kin, despite no differences between groups during learning or retention. This impairment correlated with the left hippocampal volume, particularly in mutation carriers. Such identification of generalization deficits in early ADAD may provide an easily implementable and potentially linguistically and culturally neutral way to identify and track cognition in ADAD.

Investigating trehalose synthesis genes after cold acclimation in the Antarctic nematode Panagrolaimus sp. DAW1.

Panagrolaimus sp. DAW1 is a freeze-tolerant Antarctic nematode which survives extensive intracellular ice formation. The molecular mechanisms of this extreme adaptation are still poorly understood. We recently showed that desiccation-enhanced RNA interference (RNAi) soaking can be used in conjunction with quantitative polymerase chain reaction (qPCR) to screen for phenotypes associated with reduced expression of candidate genes in Panagrolaimus sp. DAW1. Here, we present the use of this approach to investigate the role of trehalose synthesis genes in this remarkable organism. Previous studies have shown that acclimating Panagrolaimus sp. DAW1 at 5°C before freezing or desiccation substantially enhances survival. In this study, the expression of tps-2 and other genes associated with trehalose metabolism, as well as lea-1, hsp-70 and gpx-1, in cold-acclimated and non-acclimated nematodes was analyzed using qPCR. Pd-tps-2 and Pd-lea-1 were significantly upregulated after cold acclimation, indicating an inducible expression in the cold adaptation of Panagrolaimus sp. DAW1. The role of trehalose synthesis genes in Panagrolaimus sp. DAW1 was further investigated by RNAi. Compared to the controls, Pd-tps-2a(RNAi)-treated and cold-acclimated nematodes showed a significant decrease in mRNA, but no change in trehalose content or freezing survival. The involvement of two other trehalose synthesis genes (tps-2b and gob-1) was also investigated. These findings provide the first functional genomic investigation of trehalose synthesis genes in the non-model organism Panagrolaimus sp. DAW1. The presence of several trehalose synthesis genes with different RNAi sensitivities suggests the existence of multiple backup systems in Panagrolaimus sp. DAW1, underlining the importance of this sugar in preparation for freezing.

Molecular snapshot of an intracellular freezing event in an Antarctic nematode.

The Antarctic nematode, Panagrolaimus sp. DAW1 (formerly called Panagrolaimus davidi), is the best documented example of an organism able to survive intracellular ice formation in all of its compartments. Not only is it able to survive such extreme physiological disruption, but it is able to produce progeny once thawed from such a state. In addition, under slower rates, or less extreme degrees, of cooling, its body remains unfrozen and the vapour pressure difference between the supercooled body fluids and the surrounding ice leads to a process termed cryoprotective dehydration. In contrast to a fairly large body of work in building up our molecular understanding of cryoprotective dehydration, no comparable work has been undertaken on intracellular freezing. This paper describes an experiment subjecting cultures of Panagrolaimus sp. DAW1 to a range of temperatures including a rapid descent to -10 °C, in a medium just prior to, and after, freezing. Through deep sequencing of RNA libraries we have gained a snapshot of which genes are highly abundant when P. sp. DAW1 is undergoing an intracellular freezing event. The onset of freezing correlated with a high production of genes involved in cuticle formation and subsequently, after 24 h in a frozen state, protease production. In addition to the mapping of RNA sequencing, we have focused on a select set of genes arising both from the expression profiles, as well as implicated from other cold tolerance studies, to undertake qPCR. Among the most abundantly represented transcripts in the RNA mapping is the zinc-metalloenzyme, neprilysin, which also shows a particularly strong upregulated signal through qPCR once the nematodes have frozen.

Establishing RNAi in a Non-Model Organism: The Antarctic Nematode Panagrolaimus sp. DAW1.

The Antarctic nematode Panagrolaimus sp. DAW1 is one of the only organisms known to survive extensive intracellular freezing throughout its tissues. Although the physiological mechanisms of this extreme adaptation are partly understood, the molecular mechanisms remain largely unknown. RNAi is a method that allows the examination of gene function in a direct, targeted manner, by knocking out specific mRNAs and revealing the effects on the phenotype. In this study we have explored the viability of RNAi in Panagrolaimus sp. DAW1. In the first trial, nematodes were fed E. coli expressing Panagrolaimus sp. DAW1 dsRNA of the embryonic lethal genes rps-2 and dhc, and the blister gene duox. Pd-rps-2(RNAi)-treated nematodes showed a significant decrease in larval hatching. However, qPCR showed no significant decrease in the amount of rps-2 mRNA in Pd-rps-2(RNAi)-treated animals. Several soaking protocols for dsRNA uptake were investigated using the fluorescent dye FITC. Desiccation-enhanced soaking showed the strongest uptake of FITC and resulted in a significant and consistent decrease of mRNA levels of two of the four tested genes (rps-2 and tps-2a), suggesting effective uptake of dsRNA-containing solution by the nematode. These findings suggest that RNAi by desiccation-enhanced soaking is viable in Panagrolaimus sp. DAW1 and provide the first functional genomic approach to investigate freezing tolerance in this non-model organism. RNAi, in conjunction with qPCR, can be used to screen for candidate genes involved in intracellular freezing tolerance in Panagrolaimus sp. DAW1.

Widespread white matter and conduction defects in PSEN1-related spastic paraparesis.

The mechanisms underlying presenilin 1 (PSEN1) mutation-associated spastic paraparesis (SP) are not clear. We compared diffusion and volumetric magnetic resonance measures between 3 persons with SP associated with the A431E mutation and 7 symptomatic persons with PSEN1 mutations without SP matched for symptom duration. We performed amyloid imaging and central motor and somatosensory conduction studies in 1 subject with SP. We found decreases in fractional anisotropy and increases in mean diffusivity in widespread white-matter areas including the corpus callosum, occipital, parietal, and frontal lobes in PSEN1 mutation carriers with SP. Volumetric measures were not different, and amyloid imaging showed low signal in sensorimotor cortex and other areas in a single subject with SP. Electrophysiological studies demonstrated both slowed motor and sensory conduction in the lower extremities in this same subject. Our results suggest that SP in carriers of the A431E PSEN1 mutation is a manifestation of widespread white-matter abnormalities not confined to the corticospinal tract that is at most indirectly related to the mutation's effect on amyloid precursor protein processing and amyloid deposition.

The ability to survive intracellular freezing in nematodes is related to the pattern and distribution of ice formed.

A few species of nematodes can survive extensive intracellular freezing throughout all their tissues, an event that is usually thought to be fatal to cells. How are they able to survive in this remarkable way? The pattern and distribution of ice formed, after freezing at -10°C, can be observed using freeze substitution and transmission electron microscopy, which preserves the former position of ice as white spaces. We compared the pattern and distribution of ice formed in a nematode that survives intracellular freezing well (Panagrolaimus sp. DAW1), one that survives poorly (Panagrellus redivivus) and one with intermediate levels of survival (Plectus murrayi). We also examined Panagrolaimus sp. in which the survival of freezing had been compromised by starvation. Levels of survival were as expected and the use of vital dyes indicated cellular damage in those that survived poorly (starved Panagrolaimus sp. and P. murrayi). In fed Panagrolaimus sp. the intracellular ice spaces were small and uniform, whereas in P. redivivus and starved Panagrolaimus sp. there were some large spaces that may be causing cellular damage. The pattern and distribution of ice formed was different in P. murrayi, with a greater number of individuals having no ice or only small intracellular ice spaces. Control of the size of the ice formed is thus important for the survival of intracellular freezing in nematodes.

Ice-Active Substances from the Infective Juveniles of the Freeze Tolerant Entomopathogenic Nematode, Steinernema feltiae.

Steinernema feltiae is a moderately freezing tolerant nematode, that can withstand intracellular ice formation. We investigated recrystallization inhibition, thermal hysteresis and ice nucleation activities in the infective juveniles of S. feltiae. Both the splat cooling assay and optical recrystallometry indicate the presence of ice active substances that inhibit recrystallization in the nematode extract. The substance is relatively heat stable and largely retains the recrystallization inhibition activity after heating. No thermal hysteresis activity was detected but the extract had a typical hexagonal crystal shape when grown from a single seed crystal and weak ice nucleation activity. An ice active substance is present in a low concentration, which may be involved in the freezing survival of this species by inhibiting ice recrystallization.

Infective Juveniles of the Entomopathogenic Nematode, Steinernema feltiae Produce Cryoprotectants in Response to Freezing and Cold Acclimation.

Steinernema feltiae is a moderately freeze-tolerant entomopathogenic nematode which survives intracellular freezing. We have detected by gas chromatography that infective juveniles of S. feltiae produce cryoprotectants in response to cold acclimation and to freezing. Since the survival of this nematode varies with temperature, we analyzed their cryoprotectant profiles under different acclimation and freezing regimes. The principal cryoprotectants detected were trehalose and glycerol with glucose being the minor component. The amount of cryoprotectants varied with the temperature and duration of exposure. Trehalose was accumulated in higher concentrations when nematodes were acclimated at 5°C for two weeks whereas glycerol level decreased from that of the non-acclimated controls. Nematodes were seeded with a small ice crystal and held at -1°C, a regime that does not produce freezing of the nematodes but their bodies lose water to the surrounding ice (cryoprotective dehydration). This increased the levels of both trehalose and glycerol, with glycerol reaching a higher concentration than trehalose. Nematodes frozen at -3°C, a regime that produces freezing of the nematodes and results in intracellular ice formation, had elevated glycerol levels while trehalose levels did not change. Steinernema feltiae thus has two strategies of cryoprotectant accumulation: one is an acclimation response to low temperature when the body fluids are in a cooled or supercooled state and the infective juveniles produce trehalose before freezing. During this process a portion of the glycerol is converted to trehalose. The second strategy is a rapid response to freezing which induces the production of glycerol but trehalose levels do not change. These low molecular weight compounds are surmised to act as cryoprotectants for this species and to play an important role in its freezing tolerance.