Associations between specialty care and improved outcomes among patients with diabetic foot ulcers

OBJECTIVE

Specialty care may improve diabetic foot ulcer outcomes. Medically underserved populations receive less specialty care. We aimed to determine the association between specialty care and ulcer progression, major amputation, or death. If a beneficial association is found, increasing access to specialty care might help advance health equity.

RESEARCH DESIGN AND METHODS

We retrospectively analyzed a cohort of Wisconsin and Illinois Medicare patients with diabetic foot ulcers (n = 55,409), stratified by ulcer severity (i.e., early stage, osteomyelitis, or gangrene). Within each stratum, we constructed Kaplan-Meier curves for event-free survival, defining events as: ulcer progression, major amputation, or death. Patients were grouped based on whether they received specialty care from at least one of six disciplines: endocrinology, infectious disease, orthopedic surgery, plastic surgery, podiatry, and vascular surgery. Multivariate Cox proportional hazard models estimated the association between specialty care and event-free survival, adjusting for sociodemographic factors and comorbidities, and stratifying on ulcer severity.

RESULTS

Patients who received specialty care had longer event-free survival compared to those who did not (log-rank p<0.001 for all ulcer severity strata). After adjusting, receipt of specialty care, compared to never, remained associated with improved outcomes for all ulcer severities (early stage adjusted hazard ratio 0.34, 95% CI 0.33-0.35, p<0.001; osteomyelitis aHR 0.22, 95% CI 0.20-0.23, p<0.001; gangrene aHR 0.22, 95% CI 0.20-0.24, p<0.001).

CONCLUSIONS

Specialty care was associated with longer event-free survivals for patients with diabetic foot ulcers. Increased, equitable access to specialty care might improve diabetic foot ulcer outcomes and disparities.

Regional and racial disparities in major amputation rates among medicare beneficiaries with diabetes: a retrospective study in the southeastern USA

Objective

While rates for non-traumatic lower extremity amputations (LEA) have been declining, concerns exist over disparities. Our objectives are to track major LEA (MLEA) rates over time among Medicare beneficiaries residing in a high diabetes prevalence region in the southeastern USA (the diabetes belt) and surrounding areas.

Methods

We used Medicare claims files for ~900 000 fee-for-service beneficiaries aged ≥65 years in 2006-2015 to track MLEA rates per 1000 patients with diabetes. We additionally conducted a cross-sectional analysis of data for 2015 to compare regional and racial disparities in major amputation risks after adjusting for demographic, socioeconomic, access-to-care and foot complications and other health factors. The Centers for Disease Control and Prevention defined the diabetes belt as 644 counties across Appalachian and southeastern US counties with high prevalence.

Results

MLEA rates were 3.9 per 1000 in the Belt compared with 2.8 in the surrounding counties in 2006 and decreased to 2.3 and 1.6 in 2015. Non-Hispanic black patients had 8.5 and 6.9 MLEAs per 1000 in 2006 and 4.8 and 3.5 in 2015 in the Belt and surrounding counties, respectively, while the rates were similar for non-Hispanic white patients in the two areas. Although amputation rates declined rapidly in both areas, non-Hispanic black patients in the Belt consistently had >3 times higher rates than non-Hispanic whites in the Belt. After adjusting for patient demographics, foot complications and healthcare access, non-Hispanic blacks in the Belt had about twice higher odds of MLEAs compared with non-Hispanic whites in the surrounding areas.

Discussion

Our data show persistent disparities in major amputation rates between the diabetes belt and surrounding counties. Racial disparities were much larger in the Belt. Targeted policies to prevent MLEAs among non-Hispanic black patients are needed to reduce persistent disparities in the Belt.

Association of rurality and identifying as black with receipt of specialty care among patients hospitalized with a diabetic foot ulcer: a Medicare cohort study

INTRODUCTION

Rural patients with diabetic foot ulcers, especially those identifying as black, face increased risk of major amputation. Specialty care can reduce this risk. However, care disparities might beget outcome disparities. We aimed to determine whether a smaller proportion of rural patients, particularly those identifying as black, receive specialty care compared with the national proportion.

RESEARCH DESIGN AND METHODS

This 100% national retrospective cohort examined Medicare beneficiaries hospitalized with diabetic foot ulcers (2013-2014). We report observed differences in specialty care, including: endocrinology, infectious disease, orthopedic surgery, plastic surgery, podiatry, or vascular surgery. We used logistic regression to examine possible intersectionality between rurality and race, controlling for sociodemographics, comorbidities, and ulcer severity and including an interaction term between rurality and identifying as black.

RESULTS

Overall, 32.15% (n=124 487) of patients hospitalized with a diabetic foot ulcer received specialty care. Among rural patients (n=13 100), the proportion decreased to 29.57%. For patients identifying as black (n=21 649), the proportion was 33.08%. Among rural patients identifying as black (n=1239), 26.23% received specialty care. This was >5 absolute percentage points less than the overall cohort. The adjusted OR for receiving specialty care among rural versus urban patients identifying as black was 0.61 (95% CI 0.53 to 0.71), which was lower than that for rural versus urban patients identifying as white (aOR 0.85, 95% CI 0.80 to 0.89). This metric supported a role for intersectionality between rurality and identifying as black.

CONCLUSIONS

A smaller proportion of rural patients, particularly those identifying as black, received specialty care when hospitalized with a diabetic foot ulcer compared with the overall cohort. This might contribute to known disparities in major amputations. Future studies are needed to determine causality.

Using the National Institute on Minority Health and Health Disparities framework to better understand disparities in major amputations

Recently, the United States experienced its first resurgence of major amputations in more than 20 years. Compounding this rise is a longstanding history of disparities. Patients identifying as non-Hispanic Black are twice as likely to lose a limb as those identifying as non-Hispanic White. Those identifying as Latino face a 30% increase. Rural patients are also more likely to undergo major amputations, and the rural-urban disparity is widening. We used the National Institute on Minority Health and Health Disparities framework to better understand these disparities and identify common factors contributing to them. Common factors were abundant and included increased prevalence of diabetes, possible lower rates of foot self-care, transportation barriers to medical appointments, living in disadvantaged neighborhoods, and lack of insurance. Solutions within and outside the health care realm are needed. Health care-specific interventions that embed preventative and ambulatory care services within communities may be particularly high yield.

1659. Association of Rurality and Identifying as Black with Receipt of Specialty Care among Patients Hospitalized with Diabetic Foot Ulcers: a Medicare cohort study

Background

Among those with diabetic foot ulcers, rural patients identifying as Black face at least 10% greater risk of major amputation or death compared to the US as a whole. As specialty care is associated with lower risk of major amputation, this difference could be driven by specialty care access. We hypothesize that rural patients and, particularly, rural patients identifying as Black, receive less inpatient specialty care compared to the overall cohort.

Methods

We built a cohort of all Medicare patients hospitalized with diabetic foot ulcers (2013–2014). Rurality was measured using Rural Urban Commuting Area codes. Race was categorized using the Research Triangle Institute algorithm. Specialty care was defined as receiving inpatient care from at least 1 of 6 relevant specialties to address diabetes, infection, biomechanics or vascular disease, per National Provider Taxonomy codes: endocrinology, infectious disease, orthopedic surgery, plastic surgery, podiatry, and vascular surgery. We reported observed differences in specialty care, overall and stratified by rurality, identifying as Black, and ulcer severity. Pearson X² tests were performed on observed frequencies.

Results

Overall, 32.2% of the cohort received inpatient specialty care. This proportion decreased to 29.6% for rural patients (X² = 36.2, p ≤ 0.001) and 26.2% for rural patients identifying as Black (X² = 19.5, p ≤ 0.001). Among those with osteomyelitis, 54.3% of the cohort received specialty care, while only 49.5% of rural patients, 50.8% of patients identifying as Black, and 37.6% of rural patients identifying as Black received specialty care; the disparity for rural patients identifying as Black was greater than the sum of rural and racial disparities (4.8% for rural + 3.5% for Blacks = 8.3% versus a 16.7% observed difference for rural Blacks; Figure 1). Notably, only 2.7% of patients presenting with osteomyelitis were seen by an infectious disease specialist. This proportion decreased to 2.5% for rural patients.

Observed Proportions of Patients Receiving Specialty Care Stratified by Rurality, Identifying as Black, and Ulcer Severity

Conclusion

A smaller proportion of rural patients received specialty care, and rural patients identifying as Black were half as likely to receive specialty care than the overall cohort. Improving specialty access for these high-risk patients may reduce disparities in major amputations.

Disclosures

All Authors: No reported disclosures.

Effect of health system on the association of rurality and level of disadvantage with receipt of diabetic eye screening

INTRODUCTION

Rural versus urban disparities have been observed in diabetic eye screening, but whether the level of disadvantage in rural versus urban areas is related to these disparities is unclear. Our goal was to determine the role of level of disadvantage in explaining the effect of health systems on rural and urban disparities in diabetic eye screening.

RESEARCH DESIGN AND METHODS

This is a retrospective cohort study using an all-payer, state-wide claims database covering over 75% of Wisconsin residents. We included adults with diabetes (18-75 years old) who had claims billed throughout the baseline (2012-2013) and measurement (2013-2014) years. We performed multivariable regressions to assess factors associated with receipt of diabetic eye screening. The primary exposure was the primary care clinic's combined level of rurality and disadvantage. We adjusted for the health system as well as patient-level variables related to demographics and comorbidities. Health system was defined as an associated group of physicians and/or clinics.

RESULTS

A total of 118 707 adults with diabetes from 698 primary care clinics in 143 health systems met the inclusion criteria. Patients from urban underserved clinics were less likely to receive screening than those from rural underserved clinics before adjusting for health system in the model. After adjusting for health system fixed effects, however, the directionality of the relationship between clinic rurality and screening reversed: patients from urban underserved clinics were more likely to receive screening than those from rural underserved clinics. Similar findings were observed for both Medicare and non-Medicare subgroups.

CONCLUSIONS

The effect of health system on receipt of diabetic eye screening in rural versus urban areas is most pronounced in underserved areas. Health systems, particularly those providing care to urban underserved populations, have an opportunity to increase screening rates by leveraging health system-level interventions to support patients in overcoming barriers from social determinants of health.

Ankle brachial indices and anaerobes: is peripheral arterial disease associated with anaerobic bacteria in diabetic foot ulcers?

Background

Lower extremity amputations from diabetic foot ulcers (DFUs) are rebounding, and new biomarkers that predict wound healing are urgently needed. Anaerobic bacteria have been associated with persistent ulcers and may be a promising biomarker beyond currently recommended vascular assessments. It is unknown whether anaerobic markers are simply a downstream outcome of peripheral arterial disease (PAD) and ischemia, however. Here, we evaluate associations between two measures of anaerobic bacteria-abundance and metabolic activity-and PAD.

Methods

We built a prospective cohort of 37 patients with baseline ankle brachial index (ABI) results. Anaerobic bacteria were measured in two ways: DNA-based total anaerobic abundance using 16S rRNA gene amplicon sequencing and resulting summed relative abundance, and RNA-based metabolic activity based on bacterial read annotation of metatranscriptomic sequencing. PAD was defined three ways: PAD diagnosis, ABI results, and a dichotomous definition of mild ischemia (versus normal) based on ABI values. Statistical associations between anaerobes and PAD were evaluated using univariate odds ratios (ORs) or Spearman's correlations.

Results

Total anaerobe abundance was not significantly associated with PAD diagnosis, ABI results, or mild ischemia (ORPAD = 0.47, 95% CI = 0.023-7.23, p = 0.60; Spearman's correlation coefficientABI = 0.24, p = 0.17; ORmild ischemia = 0.25, 95% CI = 0.005-5.86, p = 0.42). Anaerobic metabolic activity was not significantly associated with PAD diagnosis, ABI results, or mild ischemia (ORPAD = 1.99, 95% CI = 0.17-21.44, p = 0.57; Spearman's correlation coefficientABI = 0.12, p = 0.52; ORmild ischemia = 0.90, 95% CI = 0.03-15.16, p = 0.94).

Conclusion

Neither anaerobic abundance nor metabolic activity was strongly associated with our three definitions of PAD. Therefore, anaerobic bacteria may offer additional prognostic value when assessing wound healing potential and should be investigated as potential molecular biomarkers for DFU outcomes.

Use of Novel Strategies to Develop Guidelines for Management of Pyogenic Osteomyelitis in Adults: A WikiGuidelines Group Consensus Statement

IMPORTANCE

Traditional approaches to practice guidelines frequently result in dissociation between strength of recommendation and quality of evidence.

OBJECTIVE

To construct a clinical guideline for pyogenic osteomyelitis management, with a new standard of evidence to resolve the gap between strength of recommendation and quality of evidence, through the use of a novel open access approach utilizing social media tools.

EVIDENCE REVIEW

This consensus statement and systematic review study used a novel approach from the WikiGuidelines Group, an open access collaborative research project, to construct clinical guidelines for pyogenic osteomyelitis. In June 2021 and February 2022, authors recruited via social media conducted multiple PubMed literature searches, including all years and languages, regarding osteomyelitis management; criteria for article quality and inclusion were specified in the group's charter. The GRADE system for evaluating evidence was not used based on previously published concerns regarding the potential dissociation between strength of recommendation and quality of evidence. Instead, the charter required that clear recommendations be made only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were drafted to discuss pros and cons of care choices. Both clear recommendations and clinical reviews were planned with the intention to be regularly updated as new data become available.

FINDINGS

Sixty-three participants with diverse expertise from 8 countries developed the group's charter and its first guideline on pyogenic osteomyelitis. These participants included both nonacademic and academic physicians and pharmacists specializing in general internal medicine or hospital medicine, infectious diseases, orthopedic surgery, pharmacology, and medical microbiology. Of the 7 questions addressed in the guideline, 2 clear recommendations were offered for the use of oral antibiotic therapy and the duration of therapy. In addition, 5 clinical reviews were authored addressing diagnosis, approaches to osteomyelitis underlying a pressure ulcer, timing for the administration of empirical therapy, specific antimicrobial options (including empirical regimens, use of antimicrobials targeting resistant pathogens, the role of bone penetration, and the use of rifampin as adjunctive therapy), and the role of biomarkers and imaging to assess responses to therapy.

CONCLUSIONS AND RELEVANCE

The WikiGuidelines approach offers a novel methodology for clinical guideline development that precludes recommendations based on low-quality data or opinion. The primary limitation is the need for more rigorous clinical investigations, enabling additional clear recommendations for clinical questions currently unresolved by high-quality data.

Association of Race, Ethnicity, and Rurality With Major Leg Amputation or Death Among Medicare Beneficiaries Hospitalized With Diabetic Foot Ulcers

IMPORTANCE

Patients identifying as Black and those living in rural and disadvantaged neighborhoods are at increased risk of major (above-ankle) leg amputations owing to diabetic foot ulcers. Intersectionality emphasizes that the disparities faced by multiply marginalized people (eg, rural US individuals identifying as Black) are greater than the sum of each individual disparity.

OBJECTIVE

To assess whether intersecting identities of Black race, ethnicity, rural residence, or living in a disadvantaged neighborhood are associated with increased risk in major leg amputation or death among Medicare beneficiaries hospitalized with diabetic foot ulcers.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used 2013-2014 data from the US National Medicare Claims Data Database on all adult Medicare patients hospitalized with a diabetic foot ulcer. Statistical analysis was conducted from August 1 to October 27, 2021.

EXPOSURES

Race was categorized using Research Triangle Institute variables. Rurality was assigned using Rural-Urban Commuting Area codes. Residents of disadvantaged neighborhoods comprised those living in neighborhoods at or above the national 80th percentile Area Deprivation Index.

MAIN OUTCOMES AND MEASURES

Major leg amputation or death during hospitalization or within 30 days of hospital discharge. Logistic regression was used to explore interactions among race, ethnicity, rurality, and neighborhood disadvantage, controlling for sociodemographic characteristics, comorbidities, and ulcer severity.

RESULTS

The cohort included 124 487 patients, with a mean (SD) age of 71.5 (13.0) years, of whom 71 286 (57.3%) were men, 13 100 (10.5%) were rural, and 21 649 (17.4%) identified as Black. Overall, 17.6% of the cohort (n = 21 919), 18.3% of rural patients (2402 of 13 100), and 21.9% of patients identifying as Black (4732 of 21 649) underwent major leg amputation or died. Among 1239 rural patients identifying as Black, this proportion was 28.0% (n = 347). This proportion exceeded the expected excess for rural patients (18.3% - 17.6% = 0.7%) plus those identifying as Black (21.9% - 17.6% = 4.3%) by more than 2-fold (28.0% - 17.6% = 10.4% vs 0.7% + 4.3% = 5.0%). The adjusted predicted probability of major leg amputation or death remained high at 24.7% (95% CI, 22.4%-26.9%), with a significant interaction between race and rurality.

CONCLUSIONS AND RELEVANCE

Rural patients identifying as Black had a more than 10% absolute increased risk of major leg amputation or death compared with the overall cohort. This study suggests that racial and rural disparities interacted, amplifying risk. Findings support using an intersectionality lens to investigate and address disparities in major leg amputation and mortality for patients with diabetic foot ulcers.

Analysis of Health System Size and Variability in Diabetic Eye Disease Screening in Wisconsin

This cohort study uses statewide claims data to assess variability in diabetic eye disease screening across Wisconsin health systems and to examine the association between patient health system and screening receipt.

COVID-19 in Health Care Personnel: Significance of Health Care Role, Contact History, and Symptoms in Those Who Test Positive for SARS-CoV-2 Infection

OBJECTIVE

To identify significant factors that help predict whether health care personnel (HCP) will test positive for severe acute respiratory coronavirus 2 (SARS-CoV-2).

PATIENTS AND METHODS

We conducted a prospective cohort study among 7015 symptomatic HCP from March 25, 2020, through November 11, 2020. We analyzed the associations between health care role, contact history, symptoms, and a positive nasopharyngeal swab SARS-CoV-2 polymerase chain reaction test results, using univariate and multivariable modelling.

RESULTS

Of the symptomatic HCP, 624 (8.9%) were positive over the study period. On multivariable analysis, having a health care role other than physician or advanced practice provider, contact with family or community member with known or suspected coronavirus disease 2019 (COVID-19), and seven individual symptoms (cough, anosmia, ageusia, fever, myalgia, chills, and headache) were significantly associated with higher adjusted odds ratios for testing positive for SARS-CoV-2. For each increase in symptom number, the odds of testing positive nearly doubled (odds ratio, 1.93; 95% CI, 1.82 to 2.07, P<.001).

CONCLUSION

Symptomatic HCP have higher adjusted odds of testing positive for SARS-CoV-2 based on three distinct factors: (1) nonphysician/advanced practice provider role, (2) contact with a family or community member with suspected or known COVID-19, and (3) specific symptoms and symptom number. Differences among health care roles, which persisted after controlling for contacts, may reflect the influence of social determinants. Contacts with COVID-19-positive patients and/or HCP were not associated with higher odds of testing positive, supporting current infection control efforts. Targeted symptom and contact questionnaires may streamline symptomatic HCP testing for COVID-19.

Good working relationships: how healthcare system proximity influences trust between healthcare workers

Trust between healthcare workers is a fundamental component of effective, interprofessional collaboration and teamwork. However, little is known about how this trust is built, particularly when healthcare workers are distributed (i.e., not co-located and lack a shared electronic health record). We interviewed 39 healthcare workers who worked with proximal and distributed colleagues to care for patients with diabetic foot ulcers and analyzed transcripts using content analysis. Generally, building trust was a process that occurred over time, starting with an introduction and proceeding through iterative cycles of communication and working together to coordinate care for shared patients. Proximal, compared to distributed, dyads had more options available for interactions which, in turn, facilitated communication and working together to build trust. Distributed healthcare workers found it more difficult to develop trusting relationships and relied heavily on individual initiative to do so. Few effective tools existed at the level of interprofessional collaborations, teams, or broader healthcare systems to support trust between distributed healthcare workers. With increasing use of distributed interprofessional collaborations and teams, future efforts should focus on fostering this critical attribute.

Expect delays: poor connections between rural and urban health systems challenge multidisciplinary care for rural Americans with diabetic foot ulcers

BACKGROUND

Rural Americans with diabetic foot ulcers (DFUs) face a 50% increased risk of major amputation compared to their urban counterparts. We sought to identify health system barriers contributing to this disparity.

METHODS

We interviewed 44 participants involved in the care of rural patients with DFUs: 6 rural primary care providers (PCPs), 12 rural specialists, 12 urban specialists, 9 support staff, and 5 patients/caregivers. Directed content analysis was performed guided by a conceptual model describing how PCPs and specialists collaborate to care for shared patients.

RESULTS

Rural PCPs reported lack of training in wound care and quickly referred patients with DFUs to local podiatrists or wound care providers. Timely referrals to, and subsequent collaborations with, rural specialists were facilitated by professional connections. However, these connections often were lacking between rural providers and urban specialists, whose skills were needed to optimally treat patients with high acuity ulcers. Urban referrals, particularly to vascular surgery or infectious disease, were stymied by 1) time-consuming processes, 2) negative provider interactions, and 3) multiple, disconnected electronic health record systems. Such barriers ultimately detracted from rural PCPs' ability to focus on medical management, as well as urban specialists' ability to appropriately triage referrals due to lacking information. Subsequent collaboration between providers also suffered as a result.

CONCLUSIONS

Poor connections across rural and urban healthcare systems was described as the primary health system barrier driving the rural disparity in major amputations. Future interventions focusing on mitigating this barrier could reduce the rural disparity in major amputations.

The role of the microbiome in nonhealing diabetic wounds

Wound healing is a highly coordinated and complex process, and there can be devastating consequences if it is interrupted. It is believed that, in combination with host factors, microorganisms in a wound bed can not only impair wound healing but can lead to stalled, chronic wounds. It is hypothesized that the wound microbiota persists in chronic wounds as a biofilm, recalcitrant to antibiotic and mechanical intervention. Cultivation-based methods are the gold standard for identification of pathogens residing in wounds. However, these methods are biased against fastidious organisms, and do not capture the full extent of microbial diversity in chronic wounds. Thus, the link between specific microbes and impaired healing remains tenuous. This is partially because local infection and, more specifically, the formation of a biofilm, is difficult to diagnose. This has led to research efforts aimed at understanding if biofilm formation delays healing and leads to persistent and chronic infection. Circumventing challenges associated with culture-based estimations, advances in high-throughput sequencing analysis has revealed that chronic wounds are host to complex, diverse microbiomes comprising multiple species of bacteria and fungi. Here, we discuss how the use of genomic methodologies to study wound microbiomes has advanced the current understanding of infection and biofilm formation in chronic wounds.

Abstract P3-15-01: The effect of participation in RCT on outcomes in patients with early breast cancer compared to the general breast cancer population

Background: Breast cancer trial enrollment, while slightly higher than some other histologies, still remains low, at less than 4%. Research suggests lack of clinical trial participation is due to poor patient and clinician commitment and interest. Increasing incentive for trial participation may enhance engagement of patients and healthcare providers leading to increased patient enrollment. One incentive would be to understand benefits of trial participation with regards to better survival and outcomes. The purpose of this study is to determine differences in survival, overall and breast cancer specific, and surgical management, for women who participate in early breast cancer randomized clinical trials (RCT) compared to the general breast cancer population who received similar standard therapy outside of a RCT.

Methods: Patients included in this retrospective analysis were from one of three (3) international, randomize, adjuvant breast cancer trials (RCT-participants) and women with breast cancer from the general U.S. population, from Surveillance Epidemiology and End Results Program (SEER-13), the controls. Women diagnosed between 1997-2004 with invasive breast cancer, tumor (T) size 1-3, lymph node (LN) positive (LN1/2), hormone receptor positive or negative, HER2 positive or negative, treated with surgery, adjuvant radiation, and chemotherapy were included in the analysis. In this study, propensity score analysis (PSA) was done to provide weight to each data point for each variable in order to more closely represent similar populations. PSA, considered superior to a standard Cox multivariate analysis as it attempts to reduce the bias due to confounding or correlated predictive variables. Subsequently, the propensity score was applied to a Cox proportional hazards model to determine hazard ratios (HR), with a Wald 95% confidence interval (CI), of trial participation on survival. Similarly, PSA was done for surgical outcomes. A multivariate logistic regression was performed to calculate the odds ratios, with a Wald 95% CI, to determine if RCT participation compared to the SEER-13 control had an impact on surgical outcomes, mastectomy versus breast conserving surgery (BCS).

Results: The total sample size was 9255 patients, 1795 RCT-participants and 7460 SEER-13 controls. After controlling for all other significant predictors of survival, RCT participation significantly reduced risk of breast cancer related death at 5-years by more than 25% and 18% at 10 years [HR: 0.75 (95% CI: 0.64-0.87); p=0.00020; and HR: 0.83 (95% CI: 0.74-0.93); p=0.00165, respectively]. Additionally, we demonstrated a significant reduction in risk of all-cause mortality for RCT-participants, at both 5-years and 10-years [HR: 0.83 (95% CI: 0.72--0.95); p=0.009; and HR: 0.79 (95% CI: 0.71-0.87); p&lt;0.00001, respectively]. Additionally, RCT-participants were significantly less likely to undergo invasive surgical management (mastectomy) compared to SEER-13 controls [OR: 0.78 (95% CI: 0.66-0.92;) p=0.03].

Conclusion: RCT-participants have a reduced risk of death at 5 years and 10 years compared to the general breast cancer population. Additionally, RCT-participants are less likely to undergo mastectomy than the SEER-13 controls.

Citation Format: Brennan MB, Wiley D, Wang D, Wang X, Fasching P. The effect of participation in RCT on outcomes in patients with early breast cancer compared to the general breast cancer population [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-15-01.

Transmission of Babesia microti Parasites by Solid Organ Transplantation

Infection with this parasite should be included in differential diagnosis of fever and anemia after blood transfusion or organ transplantation.

Babesia microti, an intraerythrocytic parasite, is tickborne in nature. In contrast to transmission by blood transfusion, which has been well documented, transmission associated with solid organ transplantation has not been reported. We describe parasitologically confirmed cases of babesiosis diagnosed ≈8 weeks posttransplantation in 2 recipients of renal allografts from an organ donor who was multiply transfused on the day he died from traumatic injuries. The organ donor and recipients had no identified risk factors for tickborne infection. Antibodies against B. microti parasites were not detected by serologic testing of archived pretransplant specimens. However, 1 of the organ donor’s blood donors was seropositive when tested postdonation and had risk factors for tick exposure. The organ donor probably served as a conduit of Babesia parasites from the seropositive blood donor to both kidney recipients. Babesiosis should be included in the differential diagnosis of unexplained fever and hemolytic anemia after blood transfusion or organ transplantation.

Longitudinal trends and predictors of statin use among patients with diabetes

AIM

Statins reduce morbidity and mortality among patients with diabetes, but their use remains suboptimal. Understanding trends in statin use may inform strategies for improvement.

METHODS

We enrolled a national, retrospective cohort of 899,664 veterans aged≥40years with diabetes in 2003. We followed them through 2011, dividing the nine-year follow-up into 90-day periods. For each period, we determined statin use, defined as possession of ≥30-day supply. We examine factors associated with statin uptake among baseline non-users with a multivariate model.

RESULTS

Baseline prevalence of statin use was 43%, increased by 1.8% per period (p for trend<0.001), and reached a maximum of ~59%. Statin use among non-Hispanic racial/ethnic minorities lagged behind their white counterparts. Among baseline non-users, statin use was 9% after Year 1 and reached 36% by Year 9. Factors associated with statin uptake included use of hypoglycemic agents, HbA1c between 7 and 8.9% (53-74mmol/mol), hypertension, heart failure, peripheral vascular disease, and Hispanic ethnicity.

CONCLUSION

Statin use is slowly increasing among patients with diabetes, and at varying rates within subgroups of this population. Policies that prioritize these subgroups for statin promotion may help guide future, intervention-based research to increase compliance with current guidelines.

Non-small cell lung cancer clinical trials requiring biopsies with biomarker-specific results for enrollment provide unique challenges

BACKGROUND

Clinical trials in lung cancer increasingly require patients to provide fresh tumor tissue as a prerequisite to enrollment. The effects of this requirement on enrollment rates, enrollment durations, and patient selection have not been fully elucidated.

METHODS

The authors retrospectively reviewed data generated by patients who consented to 1 or more interventional lung cancer clinical trials at the University of California-Los Angeles Jonsson Comprehensive Cancer Center between January 2013 and December 2014. Trials were considered to require a biopsy when enrollment was conditional on the procurement of tissue without intervening therapy between procurement and enrollment.

RESULTS

In total, 311 patients underwent 368 screening incidents for 1 or more of 19 trials. Trials that required a new biopsy had a longer median screening duration (34 vs 14 days) than trials that did not require a biopsy (P < .001). Trials that required a biopsy had a greater screen failure rate (49.1% vs 26.5%; P < .001), which was largely driven by patients who did not undergo the required biopsy or lacked the required biomarker. Worsening performance status led to the majority of screen failures (56.5%) among biomarker-eligible patients.

CONCLUSIONS

Although the scientific benefits of obtaining a new biopsy and requiring specific results for trial enrollment are clear, these requirements lead to a lengthening of the screening period, which, in some patients, is associated with clinical decline before enrollment. Implications for the interpretation of data from studies of this design should be explored. Cancer 2017;123:4800-7. © 2017 American Cancer Society.

Effect of Axillary Dissection vs No Axillary Dissection on 10-Year Overall Survival Among Women With Invasive Breast Cancer and Sentinel Node Metastasis: The ACOSOG Z0011 (Alliance) Randomized Clinical Trial

IMPORTANCE

The results of the American College of Surgeons Oncology Group Z0011 (ACOSOG Z0011) trial were first reported in 2005 with a median follow-up of 6.3 years. Longer follow-up was necessary because the majority of the patients had estrogen receptor-positive tumors that may recur later in the disease course (the ACOSOG is now part of the Alliance for Clinical Trials in Oncology).

OBJECTIVE

To determine whether the 10-year overall survival of patients with sentinel lymph node metastases treated with breast-conserving therapy and sentinel lymph node dissection (SLND) alone without axillary lymph node dissection (ALND) is noninferior to that of women treated with axillary dissection.

DESIGN, SETTING, AND PARTICIPANTS

The ACOSOG Z0011 phase 3 randomized clinical trial enrolled patients from May 1999 to December 2004 at 115 sites (both academic and community medical centers). The last date of follow-up was September 29, 2015, in the ACOSOG Z0011 (Alliance) trial. Eligible patients were women with clinical T1 or T2 invasive breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases.

INTERVENTIONS

All patients had planned lumpectomy, planned tangential whole-breast irradiation, and adjuvant systemic therapy. Third-field radiation was prohibited.

MAIN OUTCOMES AND MEASURES

The primary outcome was overall survival with a noninferiority hazard ratio (HR) margin of 1.3. The secondary outcome was disease-free survival.

RESULTS

Among 891 women who were randomized (median age, 55 years), 856 (96%) completed the trial (446 in the SLND alone group and 445 in the ALND group). At a median follow-up of 9.3 years (interquartile range, 6.93-10.34 years), the 10-year overall survival was 86.3% in the SLND alone group and 83.6% in the ALND group (HR, 0.85 [1-sided 95% CI, 0-1.16]; noninferiority P = .02). The 10-year disease-free survival was 80.2% in the SLND alone group and 78.2% in the ALND group (HR, 0.85 [95% CI, 0.62-1.17]; P = .32). Between year 5 and year 10, 1 regional recurrence was seen in the SLND alone group vs none in the ALND group. Ten-year regional recurrence did not differ significantly between the 2 groups.

CONCLUSIONS AND RELEVANCE

Among women with T1 or T2 invasive primary breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases, 10-year overall survival for patients treated with sentinel lymph node dissection alone was noninferior to overall survival for those treated with axillary lymph node dissection. These findings do not support routine use of axillary lymph node dissection in this patient population based on 10-year outcomes.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00003855.

Diabetic foot ulcer severity predicts mortality among veterans with type 2 diabetes

AIM

Diabetic foot ulcers are associated with an increased risk of death. We evaluated whether ulcer severity at presentation predicts mortality.

METHODS

Patients from a national, retrospective, cohort of veterans with type 2 diabetes who developed incident diabetic foot ulcers between January 1, 2006 and September 1, 2010, were followed until death or the end of the study period, January 1, 2012. Ulcers were characterized as early stage, osteomyelitis, or gangrene at presentation. Cox proportional hazard regression identified independent predictors of death, controlling for comorbidities, laboratory parameters, and healthcare utilization.

RESULTS

66,323 veterans were included in the cohort and followed for a mean of 27.7months: 1-, 2-, and 5-year survival rates were 80.80%, 69.01% and 28.64%, respectively. Compared to early stage ulcers, gangrene was associated with an increased risk of mortality (HR 1.70, 95% CI 1.57-1.83, p<0.001). The magnitude of this effect was greater than diagnosed vascular disease, i.e., coronary artery disease, peripheral arterial disease, or stroke.

CONCLUSION

Initial diabetic foot ulcer severity is a more significant predictor of subsequent mortality than coronary artery disease, peripheral arterial disease, or stroke. Unrecognized or under-estimated vascular disease and/or sepsis secondary to gangrene should be explored as possible causal explanations.

The Association Between Geographic Density of Infectious Disease Physicians and Limb Preservation in Patients With Diabetic Foot Ulcers

Background

Avoiding major (above-ankle) amputation in patients with diabetic foot ulcers is best accomplished by multidisciplinary care teams with access to infectious disease specialists. However, access to infectious disease physicians is partially influenced by geography. We assessed the effect of living in a hospital referral region with a high geographic density of infectious disease physicians on major amputation for patients with diabetic foot ulcers. We studied geographic density, rather than infectious disease consultation, to capture both the direct and indirect (eg, informal consultation) effects of access to these providers on major amputation.

Methods

We used a national retrospective cohort of 56440 Medicare enrollees with incident diabetic foot ulcers. Cox proportional hazard models were used to assess the relationship between infectious disease physician density and major amputation, while controlling for patient demographics, comorbidities, and ulcer severity.

Results

Living in hospital referral regions with high geographic density of infectious disease physicians was associated with a reduced risk of major amputation after controlling for demographics, comorbidities, and ulcer severity (hazard ratio, .83; 95% confidence interval, .75–.91; P < .001). The relationship between the geographic density of infectious disease physicians and major amputation was not different based on ulcer severity and was maintained when adjusting for socioeconomic factors and modeling amputation-free survival.

Conclusions

Infectious disease physicians may play an important role in limb salvage. Future studies should explore whether improved access to infectious disease physicians results in fewer major amputations.

Abstract P5-16-18: The effect of participation in neoadjuvant clinical trials on outcomes in patients with early breast cancer

Pathological complete response (pCR) has been shown to demonstrate improved outcomes in breast cancer. Often novel treatments, such as taxanes or HER2 based therapies, trastuzumab or pertuzumab, have shown an increase of pCR with possible impact on the prognosis of breast cancer patients. These therapies are usually introduced into the patient population through clinical trials. Therefore, it can be hypothesized participation in neoadjuvant clinical trials might improve the pCR rate in early breast cancer patients. The aim of this study was to explore this association.

Methods: This is a retrospective study of consecutive breast cancer patients who were treated with a neoadjuvant chemotherapy at a single institution. Trial participation status was known for all patients. From 1995 to 2012 the institution participated in 10 different neoadjuvant chemotherapy trials. Outside those clinical trials, patients were treated according to national neoadjuvant therapy guidelines. Patients who took part in clinical trials were compared with patients who did not take part in clinical trials with appropriate univariate tests. Additionally, logistic regression was performed with pCR as the dependent variable and commonly known predictors of pCR (tumor size and molecular subtype) as independent variables. The model was adjusted for age at diagnosis, year of treatment and trial participation status. Furthermore, exploratory survival analyses were performed.

Results: A total of 281 patients were treated within a neoadjuvant clinical trial and 822 patients outside a clinical trial. There are significant differences in the patient populations with regards to age (p=0.0009) and tumor size (&lt;0.0001). pCR rate in patients with trial participation was 21.4% and 19.0% in patients who did not take part in clinical trials. Multivariate logistic regression showed an OR of 1.393 (95%CI 0.937-2.071, p=0.1012). Exploratory survival analyses showed a better prognosis in patients taking part in clinical trials.

Conclusions: This study shows an increased chance of pCR in patients taking part in clinical trials; however the statistical test could not show statistical significance. Most likely the effect can be explained by trial participants having access to drugs which improved pCR rates, such as HER2 based therapies or taxanes.

Citation Format: Brennan MB, Wang D, Gass P, Hein A, Beckmann MW, Fasching PA. The effect of participation in neoadjuvant clinical trials on outcomes in patients with early breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-16-18.

Barriers and facilitators of hepatitis C screening among people who inject drugs: a multi-city, mixed-methods study

Background

People who inject drugs (PWID) are at high risk of contracting and transmitting and hepatitis C virus (HCV). While accurate screening tests and effective treatment are increasingly available, prior research indicates that many PWID are unaware of their HCV status.

Methods

We examined characteristics associated with HCV screening among 553 PWID utilizing a free, multi-site syringe exchange program (SEP) in 7 cities throughout Wisconsin. All participants completed an 88-item, computerized survey assessing past experiences with HCV testing, HCV transmission risk behaviors, and drug use patterns. A subset of 362 clients responded to a series of open-ended questions eliciting their perceptions of barriers and facilitators to screening for HCV. Transcripts of these responses were analyzed qualitatively using thematic analysis.

Results

Most respondents (88%) reported receiving a HCV test in the past, and most of these (74%) were tested during the preceding 12 months. Despite the availability of free HCV screening at the SEP, fewer than 20% of respondents had ever received a test at a syringe exchange site. Clients were more likely to receive HCV screening in the past year if they had a primary care provider, higher educational attainment, lived in a large metropolitan area, and a prior history of opioid overdose. Themes identified through qualitative analysis suggested important roles of access to medical care and prevention services, and nonjudgmental providers.

Conclusions

Our results suggest that drug-injecting individuals who reside in non-urban settings, who have poor access to primary care, or who have less education may encounter significant barriers to routine HCV screening. Expanded access to primary health care and prevention services, especially in non-urban areas, could address an unmet need for individuals at high risk for HCV.

Barriers and facilitators of universal HIV screening among internal medicine residents

BACKGROUND

Adoption of universal HIV screening has been low despite national recommendations.

OBJECTIVE

To describe the barriers and facilitators to adoption of universal HIV screening in a low-prevalence setting.

DESIGN

Qualitative, thematic analysis of focus group discussions among internal medicine residents who introduced universal HIV screening into their primary care practice in Madison, Wisconsin.

APPROACH

Deductive and inductive codes constructed a hybridized thematic analysis model. Deductive codes stemmed from a knowledge-attitude-behavior framework for physician nonadherence to guidelines. Inductive codes emerged from the focus group discussions and were embedded into broader deductive codes to provide an HIV-specific model.

KEY RESULTS

Residents were knowledgeable and had positive attitudes toward recommendations for universal HIV screening. Residents felt the majority of their patients were receptive to HIV screening, especially when introduced with normalizing techniques and reference to an expert authority such as the Centers for Disease Control and Prevention (CDC). They still perceived patient discussions as challenging due to stigma surrounding HIV and patients' perceptions of being at low risk. Residents employed individualized electronic medical record cues as a memory aid to discuss the issue.

CONCLUSION

This qualitative study of internal medicine residents training in an area with low HIV prevalence suggests that stigma and patient perception of being at low risk are barriers that should be addressed to effectively integrate universal HIV screening into primary care.

Identifying transcribed sequences in arrayed bacteriophage or cosmid libraries

This unit describes methods for identifying bacteriophage or cosmid clones that contain sequences present in the mRNA of a cell line or tissue. In the , a radiolabeled cDNA probe is synthesized by reverse transcription of poly(A)+ RNA isolated from the cell line or tissue of interest. The probe is incubated with DNA-cellulose to remove highly repetitive sequences before it is used for hybridization analysis of filters from a phage or cosmid genomic library. After identification of positive clones from the library screen, the same probe can be used to screen Southern blots of restriction enzyme-digested DNA from the positive clones. Support protocols describe preparation and testing of DNA-cellulose.

Proopiomelanocortin heterozygous and homozygous null mutant mice develop pituitary adenomas

Mice lacking all pro-opiomelanocortin (POMC)-derived peptides have been created by gene targeting of the POMC locus in embryonic stem cells. Phenotypes of the POMC null homozygous mutants include obesity, pigmentation defects, and adrenal insufficiency. Here, we report that both POMC null homozygous and heterozygous mutants also develop pituitary gland tumors, which result in their premature death. The tumors occur with 100% penetrance in both POMC heterozygous and homozygous genotypes. Histological examinations reveal that tumors start from hyperplastic focal points of melanotrophic cells within the intermediate lobe. Based on the morphological and immunohistological features, we have classified the tumors as non-invasive, non-secreting, intermediate lobe adenomas. These findings uncover potential novel roles of melanocortins in the regulation of cell proliferation.

Prediagnostic Human T Lymphotropic Virus Type I Provirus Loads Were Highest in Jamaican Children Who Developed Seborrheic Dermatitis and Severe Anemia

In a recent clinical analysis of 308 Jamaican children, human T lymphotropic virus type I (HTLV-I) infection was found to be associated with significantly higher incidence rates of seborrheic dermatitis, eczema, and persistent hyperreflexia of the lower limbs and with nonsignificantly increased rates of severe anemia and abnormal lymphocytes. Results of examination of HTLV-I viral markers in the 28 HTLV-I-infected children provided virologic support for the epidemiologic associations of HTLV-I with seborrheic dermatitis and severe anemia in childhood.

Methylene blue dye as an alternative to isosulfan blue dye for sentinel lymph node localization

BACKGROUND

Our study describes the use of methylene blue dye as an alternative to isosulfan blue dye to identify the sentinel lymph node (SLN).

METHODS

A retrospective analysis was performed of 112 breast cancer patients (113 axillae) who underwent SLN biopsy (SLNB) with methylene blue dye and (99m)Tc-labeled sulfur colloid for SLN identification. All SLNs were submitted for intraoperative frozen section analysis, hematoxylin and eosin stain, and immunohistochemical evaluation. Patients with a pathologically negative SLN did not undergo further axillary lymph node dissection.

RESULTS

Of 112 patients who underwent SLNB, the SLN was identified in 107 (95.5%); 104 (92.8%) were identified by methylene blue dye. In a subset of 99 patients with recorded isotope status in relation to blue nodes, concordant identification with both dye and isotope was observed in 94 (94.9%). Of patients with identified SLNs, 32 (29.9%) of 107 contained metastatic disease, with 31 (96.9%) of 32 identified by methylene blue dye. The SLN was the only positive node in 18 (60.0%) of 30 patients.

CONCLUSIONS

SLNB with methylene blue dye is an effective alternative to isosulfan blue dye for accurately identifying SLNs in breast cancer patients.

Increased detection of serum HHV-6 DNA sequences during multiple sclerosis (MS) exacerbations and correlation with parameters of MS disease progression

In recent years, human herpesvirus 6 (HHV-6) has been investigated as a possible causative agent for MS. To determine if the detection of HHV-6 DNA in the serum of MS patients correlates with clinical parameters of MS disease progression, a total of 215 serum samples was obtained from 59 MS patients followed prospectively for a 5-month period. These samples were analyzed for the presence of HHV-6 DNA by nested PCR and compared in parallel to MS disease activity. HHV-6 DNA was amplified in 22% (4/18) of samples obtained during a period of clinical exacerbation. Significantly fewer (P = 0.008) sera, 5.6% (11/197), obtained from MS patients during clinical remission tested positive for the presence of HHV-6 DNA. This work demonstrates that the detection of serum HHV-6 DNA is significantly correlated with clinical exacerbations in MS. Moreover, the findings presented in this study have confirmed previous reports supporting an association between MS and HHV-6 and suggest a role for this human herpesvirus in the pathogenesis of MS.

Increased HTLV-I proviral load and preferential expansion of HTLV-I Tax-specific CD8+ T cells in cerebrospinal fluid from patients with HAM/TSP

To date, high human T-cell lymphotropic virus type I proviral load in patients with human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis has been reported and is thought to be related to the pathogenesis of human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis. However, the proviral load in cerebrospinal fluid has not been well investigated. We measured human T-cell lymphotropic virus type I proviral load in cerebrospinal fluid cells from human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis patients using real-time quantitative polymerase chain reaction (TaqMan). Human T-cell lymphotropic virus type I proviral load in cerebrospinal fluid cells were significantly higher than that of the matched peripheral blood mononuclear cells, and a high ratio of human T-cell lymphotropic virus type I proviral load in cerebrospinal fluid cells to peripheral blood mononuclear cells were observed in patients with short duration of illness. Human T-cell lymphotropic virus type I Tax-specific CD8+ T cells, as detected by peptide-loaded HLA tetramers, accumulated in cerebrospinal fluid compared with that in peripheral blood mononuclear cells, while the frequency of cytomegalovirus-specific CD8+ T cells in cerebrospinal fluid was reduced. These observations suggest that accumulation of both human T-cell lymphotropic virus type I-infected cells and preferential expansion of human T-cell lymphotropic virus type I-specific CD8+ cells in cerebrospinal fluid may play a role in the pathogenesis of human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis.

Recurrence rates in patients with central or retroareolar breast cancers treated with mastectomy or lumpectomy

BACKGROUND

Although breast conservation with lumpectomy and radiation treatment has become a commonly used treatment for breast cancer, there are little data to support the use of lumpectomy for central and retroareolar breast cancers. In this study, we investigate the local and distant recurrence rates of patients with central or retroareolar breast cancers treated with lumpectomy compared with mastectomy.

METHODS

This study provides a retrospective analysis of 99 patients, from 1981 to 2000, with central or retroareolar breast cancers treated with mastectomy or lumpectomy to determine the frequency of local and distant recurrence. The mastectomy and lumpectomy patients were compared with respect to recurrence and other prognostic factors including: tumor location, tumor size, axillary nodal status, and final surgical margins.

RESULTS

The overall frequency of local recurrence was 5 of 99 (5.0%) in the entire group, 3 of 67 (4.5%) and 2 of 32 (6.3%) of patients who underwent mastectomy and lumpectomy, respectively (P >0.99). Overall, 3 patients experienced a distant recurrence as a first event, with 2 patients (3.0%) in the mastectomy group and 1 patient (3.1%) in the lumpectomy group (P >0.99). The type of surgical management was not statistically significant related to either local or distant disease recurrence, with median time to local recurrence of 3.0 years for the mastectomy patients and 5.0 years for lumpectomy patients. Of the patients with central tumors who underwent mastectomy 2 of 42 (4.8%) developed local recurrences compared with those who had a lumpectomy, 1 of 21 (4.8%). Similarly for retroareolar tumors, the local recurrence rate was 1 of 25 (4.0%) for patients undergoing mastectomy and 1 of 11 (9.1%) for those undergoing lumpectomy (P >0.99).

CONCLUSIONS

In this study there was no significant difference in local or distant failure rates of those patients with central or retroareolar tumors treated with mastectomy versus lumpectomy. We conclude lumpectomy to be a reasonable treatment option for selected patients with central or retroareolar breast cancers.

Elevated serum and cerebrospinal fluid levels of soluble human herpesvirus type 6 cellular receptor, membrane cofactor protein, in patients with multiple sclerosis

Membrane cofactor protein (CD46) is a member of a family of glycoproteins that are regulators of complement and prevent activation of complement on autologous cells. Recently, CD46 has been identified as the cellular receptor for human herpesvirus Type 6 (HHV-6). Elevated levels of soluble CD46 have been described in several autoimmune disorders, and may be implicated in the pathogenesis of these diseases. As several reports have supported an association of HHV-6 and multiple sclerosis, it was of interest to compare levels of soluble CD46 in the sera of multiple sclerosis patients to that of healthy controls, other neurological disease controls, and other inflammatory disease controls. Using an immunoaffinity column comprised of immobilized monoclonal antibodies to CD46, serum levels of soluble CD46 were found to be significantly elevated in multiple sclerosis patients compared with healthy and other neurological disease controls. Moreover, multiple sclerosis patients who tested positive for HHV-6 DNA in serum had significantly elevated levels of soluble CD46 in their serum compared with those who were negative for HHV-6 DNA. A significant increase in soluble CD46 was also found in the serum of other inflammatory disease controls tested compared to healthy controls. Additionally, a significant correlation was demonstrated between levels of soluble CD46 in the serum and cerebrospinal fluid of multiple sclerosis patients. Collectively, these data suggest that elevated levels of soluble CD46 may contribute to the pathogenesis of inflammatory diseases, including multiple sclerosis.

CD8(+) T cells are an in vivo reservoir for human T-cell lymphotropic virus type I

It is thought that human T-cell lymphotropic virus type I (HTLV-I) preferentially infects CD4(+) T cells in vivo. However, observations of high HTLV-I proviral load in patients with HTLV-I-associated myelopathy/tropical spastic paraparesis suggest that HTLV-I may infect other cell types in addition to CD4(+) T cells. To identify in vivo T-cell tropisms of HTLV-I, real-time quantitative polymerase chain reaction (PCR) and intracellular protein staining were used. A high amount of HTLV-I proviral DNA was detected from purified CD8(+) T cells by quantitative PCR (between 1.64 and 62.83 copies of HTLV-I provirus per 100 isolated CD8(+) T cells). CD8(+) T cells expressed HTLV-I-related antigens (HTLV-I Tax and p19 protein) after a short time in cultivation. These results demonstrate that CD8(+) T cells are also infected with HTLV-I and express HTLV-I antigens at levels that are comparable to HTLV-I-infected CD4(+) cells. Therefore, CD8(+) cells are an additional viral reservoir in vivo for HTLV-I and may contribute to the pathogenesis of HTLV-I-mediated disorders.

In vitro spontaneous lymphoproliferation in patients with human T-cell lymphotropic virus type I-associated neurologic disease: predominant expansion of CD8+ T cells

Peripheral blood mononuclear cells (PBMCs) from patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) proliferate spontaneously in vitro. This spontaneous lymphoproliferation (SP) is one of the immunologic hallmarks of HAM/TSP and is considered to be an important factor related to the pathogenesis of HAM/TSP. However, the cell populations involved in this phenomenon have not yet been definitively identified. To address this issue, the study directly evaluated proliferating cell subsets in SP with a flow cytometric method using bromodeoxyuridine and Ki-67. Although both CD4+ and CD8+ T cells proliferated spontaneously, the percentage of proliferating CD8+ T cells was 2 to 5 times higher than that of CD4+ T cells. In addition, more than 40% of HTLV-I Tax11-19-specific CD8+ T cells as detected by an HLA-A*0201/Tax11-19 tetramer proliferated in culture. In spite of this expansion of HTLV-I-specific CD8+ T cells, HTLV-I proviral load did not decrease. This finding will help elucidate the dynamics of in vivo virus-host immunologic interactions that permit the coexistence of high HTLV-I-specific CD8+ cytotoxic T-lymphocyte responses and high HTLV-I proviral load in HAM/TSP.

Impairment in motor learning of somatostatin null mutant mice

Somatostatin was first identified as a hypothalamic factor which inhibits the release of growth hormone from the anterior pituitary (somatotropin release inhibitory factor, SRIF). Both SRIF and its receptors were subsequently found widely distributed within and outside the nervous system, in the adult as well as in the developing organism. Reflecting this wide distribution, somatostatin has been implicated regulating a diverse array of biological processes. These include body growth, homeostasis, sensory perception, autonomous functions, rate of intestinal absorption, behavior, including cognition and memory, and developmental processes. We produced null mutant mice lacking somatostatin through targeted mutagenesis. The mutant mice are healthy, fertile, and superficially indistinguishable from their heterozygous and wildtype littermates. A 'first round' phenotype screen revealed that mice lacking somatostatin have elevated plasma growth hormone levels, despite normal body size, and have elevated basal plasma corticosterone levels. In order to uncover subtle and unexpected differences, we carried out a systematic behavioral phenotype screen which identified a significant impairment in motor learning revealed when increased demands were made on motor coordination. Motor coordination and motor learning require an intact cerebellum. While somatostatin is virtually absent from the adult cerebellum, the ligand and its receptor(s) are transiently expressed at high levels in the developing cerebellum. This result suggests the functional significance of transient expression of SRIF and its receptors in the development of the cerebellum.

Integrated control of appetite and fat metabolism by the leptin-proopiomelanocortin pathway

Leptin deficiency results in a complex obesity phenotype comprising both hyperphagia and lowered metabolism. The hyperphagia results, at least in part, from the absence of induction by leptin of melanocyte stimulating hormone (MSH) secretion in the hypothalamus; the MSH normally then binds to melanocortin-4 receptor expressing neurons and inhibits food intake. The basis for the reduced metabolic rate has been unknown. Here we show that leptin administered to leptin-deficient (ob/ob) mice results in a large increase in peripheral MSH levels; further, peripheral administration of an MSH analogue results in a reversal of their abnormally low metabolic rate, in an acceleration of weight loss during a fast, in partial restoration of thermoregulation in a cold challenge, and in inducing serum free fatty acid levels. These results support an important peripheral role for MSH in the integration of metabolism with appetite in response to perceived fat stores indicated by leptin levels.

Pronociceptive actions of dynorphin maintain chronic neuropathic pain

Whereas tissue injury increases spinal dynorphin expression, the functional relevance of this upregulation to persistent pain is unknown. Here, mice lacking the prodynorphin gene were studied for sensitivity to non-noxious and noxious stimuli, before and after induction of experimental neuropathic pain. Prodynorphin knock-out (KO) mice had normal responses to acute non-noxious stimuli and a mild increased sensitivity to some noxious stimuli. After spinal nerve ligation (SNL), both wild-type (WT) and KO mice demonstrated decreased thresholds to innocuous mechanical and to noxious thermal stimuli, indicating that dynorphin is not required for initiation of neuropathic pain. However, whereas neuropathic pain was sustained in WT mice, KO mice showed a return to baselines by post-SNL day 10. In WT mice, SNL upregulated lumbar dynorphin content on day 10, but not day 2, after injury. Intrathecal dynorphin antiserum reversed neuropathic pain in WT mice at post-SNL day 10 (when dynorphin was upregulated) but not on post-SNL day 2; intrathecal MK-801 reversed SNL-pain at both times. Opioid (mu, delta, and kappa) receptor density and G-protein activation were not different between WT and KO mice and were unchanged by SNL injury. The observations suggest (1) an early, dynorphin-independent phase of neuropathic pain and a later dynorphin-dependent stage, (2) that upregulated spinal dynorphin is pronociceptive and required for the maintenance of persistent neuropathic pain, and (3) that processes required for the initiation and the maintenance of the neuropathic pain state are distinct. Identification of mechanisms that maintain neuropathic pain appears important for strategies to treat neuropathic pain.

Generation of dynorphin knockout mice

The opioid system has important roles in controlling pain, reward and addiction, and is implicated in numerous other processes within and outside the nervous system, such as mood states, immune responses, and prenatal developmental processes. The effects of the opioid system are mediated by at least three ligands, enkephalin, endorphin, and dynorphin, which act through the opioid receptors mu, delta, and kappa. In order to dissect the roles of individual components of the opioid system, mutant mice lacking single ligands or receptors are instrumental. We report here on the generation and initial characterization of a mutant mouse strain lacking pre-prodynorphin. Dynorphin 'knockout' mice are viable, healthy, and fertile and show no overt behavioral differences to wildtype littermates. Dynorphin knockout mice constitute a valuable tool for many research areas, among them research into pain, substance abuse, and epilepsy.

Tissue distribution and variant characterization of human herpesvirus (HHV)-6: increased prevalence of HHV-6A in patients with multiple sclerosis

Human herpesvirus (HHV)-6 has been associated with the pathogenesis of multiple sclerosis (MS) on the basis of serologic, molecular, and histopathologic studies. This study sought to determine the distribution of HHV-6 in different MS body fluids, including serum, saliva, urine, and peripheral blood lymphocytes. The study results extend the observation of an increased frequency of HHV-6 DNA in serum of patients with MS to the unique detection of viral sequences in urine of a subset of patients with MS. Moreover, the HHV-6 identified in these cell-free compartments was predominantly the HHV-6A variant, which has been reported to be neurotropic. These results support the hypothesis that HHV-6 may contribute to the MS disease process.

New diagnostic techniques and treatments for early breast cancer

OBJECTIVES

To review diagnostic techniques and treatments for early breast cancer, including radiologic techniques, biomarkers, surgical techniques, radiation therapy, adjuvant chemotherapy regimens, and hormonal therapy.

DATA SOURCES

Scientific and review articles, book chapters, and clinical practice.

CONCLUSIONS

Breast cancer is a major health problem. The advances in diagnosis and treatment of early breast cancer and the amount of information available make it difficult for patients to make diagnostic and treatment decisions.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses need to be knowledgeable in the many advances in diagnostic and treatment techniques for early breast cancer to assist patients with difficult decisions.

Does sentinel lymphadenectomy improve staging and alter therapy in elderly women with breast cancer?

BACKGROUND

Routine axillary lymph node dissection (ALND) for elderly women with invasive breast cancer has been questioned because it rarely alters therapy yet carries a significant morbidity rate. Sentinel lymphadenectomy (SLND) improves axillary staging and alters therapy in women with T1 breast cancer, but it is not clear whether SLND alters therapy in elderly women with breast cancer.

METHODS

A prospective breast cancer data base was used to identify women 70 years old and older who underwent SLND for axillary staging of invasive breast cancer between 1991 and 1998.

RESULTS

There were 75 invasive breast cancers in 73 women. The mean patient age was 74.5 years (range, 70-90 years). Median tumor size was 1.4 cm (range, 0.1-6.2 cm). Of the 75 tumors, 42 (56%) had favorable primary characteristics; the remaining tumors had unfavorable characteristics. SLND was performed alone in 17 cases (23%) and was followed by completion ALND in 58 cases (77%). Positive lymph nodes were identified in 32 cases (43%); 26 (81.3%) were detected by hematoxylin and eosin stains, and 6 (18.7%) were detected by immunohistochemistry alone. Five patients (6.9%) received adjuvant chemotherapy. Seven patients (9.6%) received axillary/supraclavicular radiation for positive nodes. Ten (13.7%) of 73 patients had obvious alterations in therapy because of axillary nodal status. As a result of SLND, 3 (13.6%) of 22 patients with tumors 1.0 cm or smaller received tamoxifen, and 7 (15%) of 46 patients with tumors between 1.0 and 3.0 cm in size had changes in therapy. When patient and tumor characteristics were analyzed to determine relationships to therapeutic decision-making, nodal status was the variable most significantly associated with changes in therapy (P = .0001).

CONCLUSIONS

SLND improves axillary staging in elderly women with invasive breast cancer. Results of immunohistochemistry do not alter therapy in this group of individuals (P = .6367). In patients with small primary tumors, SLND alters therapy by increasing the number of patients receiving tamoxifen. In addition, SLND affects adjuvant systemic chemotherapy and regional radiotherapy in a significant number of patients with larger tumors, particularly tumors between 1.0 and 3.0 cm.

Prospective observational study of sentinel lymphadenectomy without further axillary dissection in patients with sentinel node-negative breast cancer

PURPOSE

Immediate complete axillary lymphadenectomy (ALND) after sentinel lymphadenectomy (SLND) has confirmed that tumor-negative sentinel nodes accurately predict tumor-free axillary nodes in breast cancer. Therefore, we hypothesized that SLND alone in patients with tumor-negative sentinel nodes would achieve axillary control, with minimal complications.

PATIENTS AND METHODS

Between October 1995 and July 1997, 133 consecutive women who had primary invasive breast tumors clinically </= 4 cm in diameter and no axillary lymphadenopathy were prospectively entered onto a trial of SLND using vital blue dye. Sentinel nodes were examined by standard microscopy or immunohistochemistry. SLND was the only axillary surgery if sentinel nodes were tumor-free. Completion ALND was performed only if sentinel nodes contained metastases or if they were not identified. Excluded from subsequent analysis were patients with unsuspected multifocal carcinoma and those who refused completion ALND. The complication and axillary recurrence rates after SLND without ALND were determined.

RESULTS

Sentinel nodes were identified in 132 (99%) of 133 patients. Eight patients were excluded from further analysis. Of the 125 assessable patients, 57 had tumor-positive sentinel nodes and one had an unsuccessful mapping procedure; these patients underwent completion ALND. In the remaining 67 patients (54%), SLND was the only axillary procedure. Complications occurred in 20 patients (35%) undergoing ALND after SLND but in only two patients (3%) undergoing SLND alone (P =.001). There were no local or axillary recurrences at a median follow-up of 39 months.

CONCLUSION

Complication rates are negligible after SLND alone. An absence of axillary recurrences supports SLND as an accurate staging alternative for breast cancer and suggests that routine ALND can be eliminated for patients with histopathologically negative sentinel nodes.

Sentinel node metastasis in patients with breast carcinoma accurately predicts immunohistochemically detectable nonsentinel node metastasis

BACKGROUND

Sentinel lymphadenectomy is highly accurate for identifying axillary metastasis from a primary breast carcinoma. Nonsentinel axillary lymph nodes (NSNs) are unlikely to contain tumor cells if the axillary sentinel node (SN) is tumor free. We previously showed that the size of the primary tumor and the size of its SN metastasis predict the risk of NSN tumor involvement detected by hematoxylin and eosin staining. This study used immunohistochemical staining (IHC) to determine the likelihood of NSN axillary metastasis in the presence of SN metastasis.

METHODS

Between 1991 and 1997, axillary lymphadenectomy was performed in 156 women (157 axillary basins) who had primary breast carcinoma with SN metastasis. By hematoxylin and eosin staining, we identified NSN metastasis in 55 axillae (35%). IHC was then used to re-examine all NSNs (1827 lymph nodes) from the remaining 102 axillae. The incidence of IHC-detected NSN involvement was analyzed with respect to clinical and tumor characteristics.

RESULTS

By using IHC, we identified NSN metastasis in 15 (14.7%) of the 102 axillae. By multivariate analysis, the size of the SN metastasis (P = .0001) and the size of the primary tumor (P = .038) were the only independent variables predicting NSN metastasis determined by using either hematoxylin and eosin staining or IHC. Only the number of SN metastases (1 vs. >1) was a significant (P = .04) predictor of IHC-detected NSN metastasis.

CONCLUSIONS

Use of IHC increases the likelihood of detection of NSN metastasis, and the risk of IHC-detected metastasis increases with the size of the SN metastasis and the size of the primary tumor. If SN involvement is micrometastatic (< or =2 mm) or detected by using IHC, tumor cells are unlikely to be found in other axillary lymph nodes in patients with a small primary tumor. The clinical significance of micrometastatic disease in lymph nodes is controversial, and a prospective randomized study is necessary to resolve this important issue.

Obesity in the mouse model of pro-opiomelanocortin deficiency responds to peripheral melanocortin

Pro-opiomelanocortin (POMC)-derived peptides (the melanocortins adrenocorticotropin, alpha-, beta- and gamma-melanocyte stimulating hormone; and the endogenous opioid beta-endorphin) have a diverse array of biological activities, including roles in pigmentation, adrenocortical function and regulation of energy stores, and in the immune system and the central and peripheral nervous systems. We show here that mice lacking the POMC-derived peptides have obesity, defective adrenal development and altered pigmentation. This phenotype is similar to that of the recently identified human POMC-deficient patients. When treated with a stable alpha-melanocyte-stimulating hormone agonist, mutant mice lost more than 40% of their excess weight after 2 weeks. Our results identify the POMC-null mutant mouse as a model for studying the human POMC-null syndrome, and indicate the therapeutic use of peripheral melanocortin in the treatment of obesity.

Isolation and characterization of the mouse homolog of the preprodynorphin (Pdyn) gene

We have isolated and sequenced the mouse preprodynorphin gene (Pdyn). The Pdyn gene can encode for six biologically active dynorphin peptides. The predicted mouse preprodynorphin has 90%, 67%, and 66% identity with the predicted rat, porcine, and human preprodynorphins, respectively. Using an RT-PCR technique, we show that the Pdyn gene starts being expressed at embryonic day 12.5, with a steep increase of expression by embryonic day 14.5; in the adult mouse it is expressed in the brain, but not in liver, heart, spleen, or kidney.