Immune biomarker evaluation of sequential tyrosine kinase inhibitor and nivolumab monotherapies in renal cell carcinoma: the phase I TRIBE trial

Background

Predictive biomarkers for immune checkpoint blockade in the second-line treatment of metastatic renal cell carcinoma (mRCC) are lacking.

Materials and methods

Patients with histologically confirmed RCC who started nivolumab after at least 4 months of tyrosine kinase inhibitors (TKIs) were recruited for this study. Serial tissue and blood samples were collected for immune biomarker evaluation. The primary endpoint was to determine the association of specific T-cell subsets with clinical outcomes tested using Wilcoxon rank sum for clinical benefit rate (CBR) and log-rank test for progression-free survival (PFS).

Results

Twenty patients were included in this trial with a median age of 64 years and followed-up for a median of 12 months. The median PFS for patients who received TKI was 13.8 months, while for those subsequently treated with nivolumab following TKI therapy, the median PFS was 2.6 months. CBR of nivolumab was 20% with two partial responses. Functionally active programmed cell death protein 1+ CD4+ T cells were enriched in non-responders (q = 0.003) and associated with worse PFS on nivolumab (P = 0.04). Responders showed a significant reduction in the effector CD4+T-cell (TEF) fraction compared to non-responders at 3 months on nivolumab (0.40 versus 0.80, P = 0.0005). CD127+CD4+ T cells were enriched in patients who developed immune-related adverse effects (q = 0.003). Using in-house validated multiplex immunohistochemistry for six markers, we measured tumour-associated immune cell densities in tissue samples. Responders to nivolumab showed a significantly higher mean of immune cell densities in tissue samples compared to non-responders (346 versus 87 cells/mm2, P = 0.04).

Conclusions

In this small study, analysis of tissue-based and peripheral blood immune cell subsets predicted clinical outcomes of nivolumab. Further studies are warranted with larger populations to validate these observations.

Leveraging a Large Language Model to Assess Quality-of-Care: Monitoring ADHD Medication Side Effects

Objective

To assess the accuracy of a large language model (LLM) in measuring clinician adherence to practice guidelines for monitoring side effects after prescribing medications for children with attention-deficit/hyperactivity disorder (ADHD).

Methods

Retrospective population-based cohort study of electronic health records. Cohort included children aged 6-11 years with ADHD diagnosis and ≥2 ADHD medication encounters (stimulants or non-stimulants prescribed) between 2015-2022 in a community-based primary healthcare network (n=1247). To identify documentation of side effects inquiry, we trained, tested, and deployed an open-source LLM (LLaMA) on all clinical notes from ADHD-related encounters (ADHD diagnosis or ADHD medication prescription), including in-clinic/telehealth and telephone encounters (n=15,593 notes). Model performance was assessed using holdout and deployment test sets, compared to manual chart review.

Results

The LLaMA model achieved excellent performance in classifying notes that contain side effects inquiry (sensitivity= 87.2%, specificity=86.3/90.3%, area under curve (AUC)=0.93/0.92 on holdout/deployment test sets). Analyses revealed no model bias in relation to patient age, sex, or insurance. Mean age (SD) at first prescription was 8.8 (1.6) years; patient characteristics were similar across patients with and without documented side effects inquiry. Rates of documented side effects inquiry were lower in telephone encounters than in-clinic/telehealth encounters (51.9% vs. 73.0%, p<0.01). Side effects inquiry was documented in 61% of encounters following stimulant prescriptions and 48% of encounters following non-stimulant prescriptions (p<0.01).

Conclusions

Deploying an LLM on a variable set of clinical notes, including telephone notes, offered scalable measurement of quality-of-care and uncovered opportunities to improve psychopharmacological medication management in primary care.

Measuring quality-of-care in treatment of young children with attention-deficit/hyperactivity disorder using pre-trained language models

OBJECTIVE

To measure pediatrician adherence to evidence-based guidelines in the treatment of young children with attention-deficit/hyperactivity disorder (ADHD) in a diverse healthcare system using natural language processing (NLP) techniques.

MATERIALS AND METHODS

We extracted structured and free-text data from electronic health records (EHRs) of all office visits (2015-2019) of children aged 4-6 years in a community-based primary healthcare network in California, who had ≥1 visits with an ICD-10 diagnosis of ADHD. Two pediatricians annotated clinical notes of the first ADHD visit for 423 patients. Inter-annotator agreement (IAA) was assessed for the recommendation for the first-line behavioral treatment (F-measure = 0.89). Four pre-trained language models, including BioClinical Bidirectional Encoder Representations from Transformers (BioClinicalBERT), were used to identify behavioral treatment recommendations using a 70/30 train/test split. For temporal validation, we deployed BioClinicalBERT on 1,020 unannotated notes from other ADHD visits and well-care visits; all positively classified notes (n = 53) and 5% of negatively classified notes (n = 50) were manually reviewed.

RESULTS

Of 423 patients, 313 (74%) were male; 298 (70%) were privately insured; 138 (33%) were White; 61 (14%) were Hispanic. The BioClinicalBERT model trained on the first ADHD visits achieved F1 = 0.76, precision = 0.81, recall = 0.72, and AUC = 0.81 [0.72-0.89]. Temporal validation achieved F1 = 0.77, precision = 0.68, and recall = 0.88. Fairness analysis revealed low model performance in publicly insured patients (F1 = 0.53).

CONCLUSION

Deploying pre-trained language models on a variable set of clinical notes accurately captured pediatrician adherence to guidelines in the treatment of children with ADHD. Validating this approach in other patient populations is needed to achieve equitable measurement of quality of care at scale and improve clinical care for mental health conditions.

Patient Characteristics Associated With Phone and Video Visits at a Tele-Urgent Care Center During the Initial COVID-19 Response: Cross-Sectional Study

BACKGROUND

Health systems rapidly adopted telemedicine as an alternative health care delivery modality in response to the COVID-19 pandemic. Demographic factors, such as age and gender, may play a role in patients' choice of a phone or video visit. However, it is unknown whether there are differences in utilization between phone and video visits.

OBJECTIVE

This study aimed to investigate patients' characteristics, patient utilization, and service characteristics of a tele-urgent care clinic during the initial response to the pandemic.

METHODS

We conducted a cross-sectional study of urgent care patients using a statewide, on-demand telemedicine clinic with board-certified physicians during the initial phases of the pandemic. The study data were collected from March 3, 2020, through May 3, 2020.

RESULTS

Of 1803 telemedicine visits, 1278 (70.9%) patients were women, 730 (40.5%) were aged 18 to 34 years, and 1423 (78.9%) were uninsured. There were significant differences between telemedicine modalities and gender (P<.001), age (P<.001), insurance status (P<.001), prescriptions given (P<.001), and wait times (P<.001). Phone visits provided significantly more access to rural areas than video visits (P<.001).

CONCLUSIONS

Our findings suggest that offering patients a combination of phone and video options provided additional flexibility for various patient subgroups, particularly patients living in rural regions with limited internet bandwidth. Differences in utilization were significant based on patient gender, age, and insurance status. We also found differences in prescription administration between phone and video visits that require additional investigation.

Toward Community-Based Natural Language Processing (CBNLP): Cocreating With Communities

Rapid development and adoption of natural language processing (NLP) techniques has led to a multitude of exciting and innovative societal and health care applications. These advancements have also generated concerns around perpetuation of historical injustices and that these tools lack cultural considerations. While traditional health care NLP techniques typically include clinical subject matter experts to extract health information or aid in interpretation, few NLP tools involve community stakeholders with lived experiences. In this perspective paper, we draw upon the field of community-based participatory research, which gathers input from community members for development of public health interventions, to identify and examine ways to equitably involve communities in developing health care NLP tools. To realize the potential of community-based NLP (CBNLP), research and development teams must thoughtfully consider mechanisms and resources needed to effectively collaborate with community members for maximal societal and ethical impact of NLP-based tools.

Recommendations for design of a mobile application to support management of anxiety and depression among Black American women

Black American women experience adverse health outcomes due to anxiety and depression. They face systemic barriers to accessing culturally appropriate mental health care leading to the underutilization of mental health services and resources. Mobile technology can be leveraged to increase access to culturally relevant resources, however, the specific needs and preferences that Black women feel are useful in an app to support management of anxiety and depression are rarely reflected in existing digital health tools. This study aims to assess what types of content, features, and important considerations should be included in the design of a mobile app tailored to support management of anxiety and depression among Black women. Focus groups were conducted with 20 women (mean age 36.6 years, SD 17.8 years), with 5 participants per group. Focus groups were led by a moderator, with notetaker present, using an interview guide to discuss topics, such as participants' attitudes and perceptions towards mental health and use of mental health services, and content, features, and concerns for design of a mobile app to support management of anxiety and depression. Descriptive qualitative content analysis was conducted. Recommendations for content were either informational (e.g., information to find a Black woman therapist) or inspirational (e.g., encouraging stories about overcoming adversity). Suggested features allow users to monitor their progress, practice healthy coping techniques, and connect with others. The importance of feeling "a sense of community" was emphasized. Transparency about who created and owns the app, and how users' data will be used and protected was recommended to establish trust. The findings from this study were consistent with previous literature which highlighted the need for educational, psychotherapy, and personal development components for mental health apps. There has been exponential growth in the digital mental health space due to the COVID-19 pandemic; however, a one-size-fits-all approach may lead to more options but continued disparity in receiving mental health care. Designing a mental health app for and with Black women may help to advance digital health equity by providing a tool that addresses their specific needs and preferences, and increase engagement.

Predicting Objective Performance Using Perceived Cognitive Workload Data in Healthcare Professionals: A Machine Learning Study

Cognitive Workload (CWL) is a fundamental concept in predicting healthcare professionals' (HCPs) objective performance. The study aims to compare the accuracy of the classical model (utilizes all six dimensions of the National Aeronautics and Space Administration Task Load Index (NASA-TLX)) and novel models (utilize four or five dimensions of NASA-TLX) in predicting HCPs' objective performance. We use a dataset from our previous human factors research studies and apply a broad selection of supervised machine learning classification techniques to develop data-driven computational models and predict objective performance. The study findings confirm that classical models are better predictors of objective performance than novel models. This has practical implications for research in health informatics, human factors and ergonomics, and human-computer interaction in healthcare. Findings, although promising, cannot be generalized as they are based on a small dataset. Future studies may investigate additional subjective and physiological measures of CWL to predict HCPs' objective performance.

Feature Engineering for Interpretable Machine Learning for Quality Assurance in Radiation Oncology

Chart checking is a time intensive process with high cognitive workload for physicists. Previous studies have partially automated and standardized chart checking, but limited studies implement data-driven approaches to reduce cognitive workload for quality assurance processes. This study aims to evaluate feature selection methods to improve the interpretability and transparency of machine learning models in predicting the degree of difficulty for a pretreatment physics chart check. We compare chi-square, mutual information, feature importance thresholding, and greedy feature selection for four different classifiers. Random forest has the highest performance with SMOTE oversampling using mutual information for feature selection (accuracy 84.0%, AUC 87.0%, precision 80.0%, recall 80.0%). This study demonstrates that feature selection methods can improve model interpretability and transparency.

Using Explainable Supervised Machine Learning to Predict Burnout in Healthcare Professionals

Burnout in healthcare professionals (HCPs) is a multi-factorial problem. There are limited studies utilizing machine learning approaches to predict HCPs' burnout during the COVID-19 pandemic. A survey consisting of demographic characteristics and work system factors was administered to 450 HCPs during the pandemic (participation rate: 59.3%). The highest performing machine learning model had an area under the receiver operating curve of 0.81. The eight key features that best predicted burnout are excessive workload, inadequate staffing, administrative burden, professional relationships, organizational culture, values and expectations, intrinsic motivation, and work-life integration. These findings provide evidence for resource allocation and implementation of interventions to reduce HCPs' burnout and improve the quality of care.

Improved Metabolite Prediction Using Microbiome Data-Based Elastic Net Models

Microbiome data are becoming increasingly available in large health cohorts, yet metabolomics data are still scant. While many studies generate microbiome data, they lack matched metabolomics data or have considerable missing proportions of metabolites. Since metabolomics is key to understanding microbial and general biological activities, the possibility of imputing individual metabolites or inferring metabolomics pathways from microbial taxonomy or metagenomics is intriguing. Importantly, current metabolomics profiling methods such as the HMP Unified Metabolic Analysis Network (HUMAnN) have unknown accuracy and are limited in their ability to predict individual metabolites. To address this gap, we developed a novel metabolite prediction method, and we present its application and evaluation in an oral microbiome study. The new method for predicting metabolites using microbiome data (ENVIM) is based on the elastic net model (ENM). ENVIM introduces an extra step to ENM to consider variable importance (VI) scores, and thus, achieves better prediction power. We investigate the metabolite prediction performance of ENVIM using metagenomic and metatranscriptomic data in a supragingival biofilm multi-omics dataset of 289 children ages 3-5 who were participants of a community-based study of early childhood oral health (ZOE 2.0) in North Carolina, United States. We further validate ENVIM in two additional publicly available multi-omics datasets generated from studies of gut health. We select gene family sets based on variable importance scores and modify the existing ENM strategy used in the MelonnPan prediction software to accommodate the unique features of microbiome and metabolome data. We evaluate metagenomic and metatranscriptomic predictors and compare the prediction performance of ENVIM to the standard ENM employed in MelonnPan. The newly developed ENVIM method showed superior metabolite predictive accuracy than MelonnPan when trained with metatranscriptomics data only, metagenomics data only, or both. Better metabolite prediction is achieved in the gut microbiome compared with the oral microbiome setting. We report the best-predictable compounds in all these three datasets from two different body sites. For example, the metabolites trehalose, maltose, stachyose, and ribose are all well predicted by the supragingival microbiome.

Evaluating the Telehealth Experience of Patients With COVID-19 Symptoms: Recommendations on Best Practices

Positive patient experiences are associated with illness recovery and adherence to medication. To evaluate the virtual care experience for patients with COVID-19 symptoms as their chief complaints. We conducted a cross-sectional study of the first cohort of patients with COVID-19 symptoms in a virtual clinic. The main end points of this study were visit volume, wait times, visit duration, patient diagnosis, prescriptions received, and satisfaction. Of the 1139 total virtual visits, 212 (24.6%) patients had COVID-19 symptoms. The average wait time (SD) for all visits was 75.5 (121.6) minutes. The average visit duration for visits was 10.5 (4.9) minutes. The highest volume of virtual visits was on Saturdays (39), and the lowest volume was on Friday (19). Patients experienced shorter wait times (SD) on the weekdays 67.1 (106.8) minutes compared to 90.3 (142.6) minutes on the weekends. The most common diagnoses for patients with COVID-19 symptoms were upper respiratory infection. Patient wait times for a telehealth visit varied depending on the time and day of appointment. Long wait times were a major drawback in the patient experience. Based on patient-reported experience, we proposed a list of general, provider, and patient telehealth best practices.

THU0113 ANTI CARBAMYLATED PROTEIN ANTIBODY IN INDIAN POPULATION WITH RHEUMATOID ARTHRITIS – A BETTER PREDICTOR OF DISEASE OUTCOME

Background:

While diagnosis of RA relies mainly on detection of RF and ACCP antibodies at present, anti carbamylated protein antibody which has strong association with severe joint damage and poorer disease outcome1can be found in even healthy individuals years before onset of symptoms of RA2,3thus enabling early initiation of DMARDs and reducing complications of RA.4

Objectives:

Assess prevalence of anti-CarP Ab in RA patients in India and assess correlation between joint involvement, X-ray erosions and extra articular features between anti-CarP Ab positive and negative RA patients.

Methods:

Cross-sectional study (2017-2019) conducted among 150 RA patients who met 2010 ACR/EULAR criteria in tertiary referral hospital. Tests for CRP, RF and ACCP were done, DAS28-CRP scores were calculated at presentation & X-ray images of hands and feet obtained.

Anti-CarP Ab was tested using ELISA. Cut-off level for positivity was defined using ROC curve as 13.48 U/mL, with specificity 92.73%, sensitivity 85.26%, PPV 95.29% and NPV 78.46%.

Results:

Venn diagram representing overlap of sero-markers

Study population had 18% males, 82% females, 72% RF+ cases (108), 78% ACCP+ cases (117) and 47.3% anti-CarP Ab+ cases (71).

48% of the 25 seronegative (RF-ACCP-) cases tested positive for anti-CarP Ab, indicating its ability in diagnosing more RA cases in conjunction with present markers.

Testing association between RF and anti-CarP Ab and between ACCP and anti-CarP Ab proved to be statistically insignificant showing that anti-CarP Ab is independent of the incumbent markers in diagnosing RA.

69.4% of RA patients with high disease activity (DAS >3.2) were positive for anti-CarP Ab and showed statistically significant association.

Association between DAS28 CRP and anti-CarP Ab

Also while 39 of 71 (54.9%) anti-CarP Ab positive RA cases had joint deformities and 23 of 71 (32.4%) of anti-CarP Ab positive cases had extra articular involvement and were statistically significant, 27 of 71 anti-CarP Ab positive cases showed joint erosions in X-ray but was not statistically significant.

In comparison, only extra articular involvement showed a statistical significance in ACCP positive patients whereas joint deformities and joint erosions on X-rays showed no correlation to ACCP.

Joint DeformityTotalΧ2p valueAbsentPresentanti-CarP antibodyNegative5029795.0090.02563.3%36.7%100.0%Positive32397145.1%54.9%100.0%Total8268150Extra articular featuresTotalΧ2p valueAbsentPresentanti-CarP antibodyNegative6811797.2780.00786.1%13.9%100.0%Positive48237167.6%32.4%100.0%Total11634150

Conclusion:

Anti-CarP antibody positivity is indicative of increased disease activity (DAS28-CRP score), joint deformities and extra articular involvement in RA patients. Aside from its presence demonstrated early in the course of RA through other studies, its ability in diagnosing RA cases in otherwise seronegative (RF and ACCP negative) population and the high sensitivity, specificity and diagnostic accuracy exhibited paves the way for its routine use as a diagnostic tool in conjunction with RF and ACCP for diagnosing RA and predicting disease outcome.

References:

[1]Shi J et al. Autoantibodies recognizing carbamylated proteins are present in sera of patients with rheumatoid arthritis and predict joint damage.Proc Natl Acad Sci USA. 2011;108(42):17372-17377.

[2]Challener GJ et al. Anti-carbamylated Protein Antibody Levels Correlate with Anti-Sa Antibody Levels in Rheumatoid Arthritis.J Rheumatol. 2016;43(2):273-281.

[3]Brink M et al. Anti-carbamylated protein antibodies in the pre-symptomatic phase of rheumatoid arthritis, their relationship with multiple anti-citrulline peptide antibodies and association with radiological damage.Arthritis Research & Therapy. 2015;17(1):25.

[4]Guidelines for the management of rheumatoid arthritis. American College of Rheumatology Ad Hoc Committee on Clinical Guidelines.Arthritis Rheum. 1996;39(5):713-722.

Disclosure of Interests:

None declared

Chemical Entity Recognition for MEDLINE Indexing

Chemical entity recognition is essential for indexing scientific literature in the MEDLINE database at the National Library of Medicine. However, the tool currently used to suggest terms for indexing, the Medical Text Indexer, was not originally conceived as a chemical recognition tool. It has instead been adapted to the task via its use of MetaMap and the addition of in-house patterns and rules. In order to develop a tool more suitable for chemical recognition, we have created a collection of 200 MEDLINE titles and abstracts annotated with genes, proteins, inorganic and organic chemicals, as well as other biological molecules. We use this collection to evaluate eleven chemical entity recognition systems, where we seek to identify a tool that effectively recognizes chemical entities for indexing and also performs well on chemical recognition beyond the indexing task. We observe the highest performance with a SciBERT ensemble.

High-dose interleukin2 - a 10-year single-site experience in the treatment of metastatic renal cell carcinoma: careful selection of patients gives an excellent outcome

Background

VEGF-targeted therapy has become the mainstay of treatment for majority of mRCC patients. For most patients, benefit is short-lived and therefore treatment remains palliative in intent. HD IL2 is an effective immunotherapy treatment capable of durable remission in some patients but its unselected use has been difficult due to its modest response rate and considerable adverse effects. Using set pathology criteria as a selection tool in clinical practice, we have been able to show improved outcomes in our previous report. Here, we present an updated and extended report of this treatment and seek to explore any pathological, clinical and treatment variables likely to predict better outcomes.

Methods

This is an extension of a previously reported clinical audit, which includes mRCC cases treated with HD IL2 between 2003 and 2013. Since 2006, tumour specimens of potential candidates were routinely reviewed prospectively and stratified into Favourable or Other categories based on constitution of histological growth pattern, namely alveolar or solid versus papillary and/or sarcomatoid architecture; clear cell versus granular cell cytoplasmic morphology. HD IL2 was preferentially offered to patients with Favourable pathology. Outcome evaluation includes response rates, survival, and treatment tolerance. Multivariate analysis was performed to explore potential prognostic and predictive factors.

Results

Among prospectively selected patients with Favourable pathology (n = 106), overall response rate was 48.1 % (51/106) with CR rate of 21.6 % (23/106). Median OS was 58.1 months. Factors associated with significantly better response and/or survival includes favourable pathology pattern, higher cycle 1 tolerance and lower number of metastatic organ sites (<3). CAIX (Carbonic anhydrase 9) has prognostic value but is not predictive of response. Toxicities were those expected of IL2 but were manageable on general medical wards, with no treatment-related death. Importantly most complete responses were durable with 76 % (23/30) cases remained relapse-free (median 39 months follow up) and 2 of the seven who relapsed had had long-term disease free survival after resection of oligometastatic relapse.

Conclusions

Our experience shows that HD IL2 remains an effective and safe treatment in well-selected cases of mRCC. The result in this single-institution patient series confirms similar outcomes to our previously reported retrospective series. Given the prospect of long-term remission, fit patients with Favourable histology and low disease burden should be considered for HD IL2 in an experienced centre. Better understanding has been gained from this in-depth analysis especially the examination of possible response predictors and strategies that can improve treatment outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0174-5) contains supplementary material, which is available to authorized users.

Expression of epidermal and transforming growth factors in pancreatic cancer

Pancreatic cancer continues to be a major clinical problem and little is known of the various cellular and molecular events associated with this malignancy. Growth factors and their receptors have important functions in the process of tumor progression. We have examined by immunocytochemistry, the expression of epidermal growth factor (EGF), its receptor (EGFR) and the transforming growth factors alpha and beta (TGF alpha and beta) in various grades of pancreatic adenocarcinoma. Expression of the growth factors was compared to their distribution in apparently normal pancreas and chronic pancreatitis. EGF, TGF alpha and TGF beta was expressed in normal pancreatic tissue while the expression of EGFR was slight and restricted. In chronic pancreatitis, this expression of EGFR increased and was found to be moderate in intensity. Expression of EGF, TGF alpha and TGF beta was similar to that seen in normal pancreas. Moderate to intense expression of EGF and TGF alpha was evident in all grades of pancreatic cancer. Expression of EGFR was intense in all these lesions. However, the most significant finding was the absence of TGF beta in all pancreatic cancer lesions. These results may have significant implications for pancreatic tumor progression. EGF and TGF alpha are growth promoters influencing the expression of EGFR. TGF beta, on the other hand exerts an anti-proliferative effect and favours differentiation. It therefore appears that the balance between EGF and TGF alpha on the one hand and TGF beta on the other may be critical in the process of tumor progression, especially if one considers chronic pancreatitis as a pre-malignant condition and the growth factor expression associated with it.

Epidermal growth factor and its receptor in cervical cancer

Epidermal growth factor (EGF) is an important growth factor regulating both normal and malignant cells. The present study analyzes the expression pattern of EGF and its receptor (EGF-R) in 424 cases of various stages of tumor progression in the uterine cervix. In all the samples studied, EGF and EGF-R expression was predominant in the basal or basaloid cells. Increased expression of the two proteins correlated with increasing histological abnormality (dysplasia). In invasive cancer, alteration of EGF expression was more evident than EGF-R. The expression pattern showed significant correlation in the basal and spinal cell layers. This increased expression of EGF observed in dysplastic and malignant cells may be due to overexpression of EGF-R and suggests its role in cellular proliferation.

Proliferating cell nuclear antigen expression and the progression of cervical intraepithelial neoplasia

Cell proliferation is an important biological aspect of a tumor cell population which can affect clinical outcome. In addition to other well established clinical and histopathological prognostic criteria? cell kinetic data have significant predictive value. This study evaluates the proliferative activity of benign, premalignant and malignant cervical tissue by analyzing the expression of the proliferating cell nuclear antigen (PCNA). PCNA is a 36 kD nuclear protein associated with the cell cycle and is directly involved in DNA synthesis during cell proliferation. A total of 122 subjects were included in the study. This included 30 benign tissue samples, 30 low grade lesions (CIN 1), 30 high grade lesions (CIN 2/3) and 32 invasive squamous carcinomas. There was significant difference in PCNA index between benign and high grade lesions as well as benign and invasive cancer. The percentage of PCNA positive cells were significantly higher in invasive carcinoma when compared with non malignant lesions. Moreover, there was also good correlation between increasing histological abnormality and PCNA expression. These results suggest that cell proliferation index as detected by PCNA expression may be useful in the evaluation of alterations in cell kinetics of various grades of cervical lesions. Such data could also possibly help explain the biological behaviour of these lesions and be useful in planning of radiotherapy for invasive cervical cancer.

An assessment of the Down syndrome antenatal screening policies of East and West Gloucestershire between 1993 and 1999

This retrospective observational study of registered pregnancies in Gloucestershire between 1 April 1993 and 31 March 1999 compares the impact of different Down syndrome antenatal screening policies on detection and amniocentesis rates. The screening policies in East and West Gloucestershire are based on early second-trimester maternal serum and maternal age screening, respectively. Maternal serum screening can identify a greater proportion of pregnancies affected by Down syndrome than a programme founded on age-based amniocentesis and 20 weeks' ultrasound. In addition, maternal serum screening of women older than 34 approximately halves the number of amniocenteses performed to detect one affected fetus. However, the proportion of pregnant women who have amniocentesis is nearly doubled by offering serum screening to women aged over 24 years. These findings of the impact of established second-trimester screening policies in low-risk populations provides an useful benchmark to compare the performance of screening procedures that will be introduced in the United Kingdom over the next 3 years.

Final STEPP results of prophylacatic versus reactive skin toxicity (ST) treatment (tx) for panitumumab (pmab)-related ST in patients (pts) with metastatic colorectal cancer (mCRC)

CRA4027

Background: Pmab, a fully human monoclonal antibody targeting the epidermal growth factor receptor (EGFR), is approved as monotherapy in the US for mCRC following disease progression (PD) and in the EU and Canada for tumors bearing wild-type (WT) KRAS. The most common toxicity with anti-EGFR inhibitors are ST. This study of pmab+ chemotherapy (CT) estimates the difference in the incidence of specific ≥ grade 2 ST of interest between pts receiving prophylactic (P) or reactive (R) skin tx. Methods: Pts had unresectable mCRC after PD with 1st-line fluoropyrimidine and oxaliplatin-based CT ± bevacizumab. Pts received either pmab 6.0mg/kg/FOLFIRI Q2W or pmab 9 mg/kg/irinotecan Q3W. Within each stratum, pts were randomized 1:1 to either P ST tx 24 hrs before the 1st dose daily for 6 wks or R ST tx after ST occurred. Tx for ST included: moisturizers, sunscreen, topical steroid, and doxycycline. Efficacy and safety were evaluated by P vs R tx groups, KRAS status (mutant [MT] vs WT), and chemotherapy status. Responses were assessed using modified RECIST with confirmation. Quality of life was assessed using the Dermatology Life Quality Index at screening, wks 2–7, and follow-up. Results: 95 pts were enrolled and randomized: 48 pts to P and 47 pts to R. During the 6 wk ST tx period, 29% of pts in the P group vs 62% of pts in the R group had protocol-specified ≥grade 2 ST. Of the 87 KRAS evaluable pts, 49 (56%) pts had WT KRAS and 38 (44%) pts had MT KRAS. Efficacy and safety are shown. Mean (SD) change in DLQI from baseline was 1.3 (2.6) for P and 4.2 (5.8) for R at wk 3 (when the median time to 1st ≥grade 2 ST was reached in the R group) and was 2.0 (2.8) for P and 2.6 (4.4) for R at wk 7. Conclusions: Prophylactic use of the skin tx regimen resulted in >50% reduction in the rate of specific ≥ grade 2 STs and improved QOL during the 6-week skin tx period vs R use. Numerical differences in favor of the P group were observed for all endpoints.

[Table: see text]

[Table: see text]

Final STEPP results of prophylacatic versus reactive skin toxicity (ST) treatment (tx) for panitumumab (pmab)-related ST in patients (pts) with metastatic colorectal cancer (mCRC)

CRA4027

The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

[Table: see text]

Pegfilgrastim in colorectal cancer (CRC) patients (pts) receiving every-two-week (Q2W) chemotherapy (CT): Long-term results from a phase II, randomized, controlled study

4072

Background: Survival in advanced CRC is prolonged by adding oxaliplatin (Ox) and/or irinotecan (Iri) to Q2W 5-fluorouracil/leucovorin (5FU/LV). Combination therapy, however, has a higher incidence of febrile neutropenia (FN) and related toxicities. This study evaluated pegfilgrastim dosing on day 4 of Q2W regimens in CRC. Here we present long-term follow-up of these pts. Methods: Advanced CRC pts were randomized (1:1) to pegfilgrastim 6mg or placebo, which was stratified by CT regimen received: FOIL, FOLFOX, or FOLFIRI. We previously reported grade 3/4 neutropenia (primary endpoint) in 43% placebo and 13% pegfilgrastim pts in the 4-cycle treatment phase (odds ratio = 0.19, 95% CI: 0.10–0.37; p < 0.0001). After end of treatment, pts were followed long term for ≤ 2 years (inclusive of ≤ 8 additional cycles) for serious adverse events (SAEs), overall survival (OS), and progression-free survival (PFS). Median follow-up time was 519 days. Kaplan-Meier methods estimated OS and PFS from study day 1. The study was not powered to detect PFS or OS differences between treatment groups. Results: Of 241 pts analyzed (123 pegfilgrastim, 118 placebo), 49% received FOLFOX, 26% FOLFIRI, and 25% FOIL. In the treatment period, 8% placebo and 2% pegfilgrastim pts had grade 3/4 FN ( Table ). Pegfilgrastim was well tolerated with no dose delays attributed to leukocytosis. Pegfilgrastim and placebo had similar PFS and OS ( Table ). No SAEs related to study drug were reported in the follow-up period. Conclusions: In this randomized, placebo-controlled study, pegfilgrastim significantly lowered neutropenic risk. Bone pain incidence in this CRC population was lower than in breast cancer pts treated with a taxane (Vogel J Clin Oncol 2005); the incidence in pegfilgrastim pts was modestly increased over placebo. Leukocytosis was not a concern despite the 11-day dosing interval. Long-term results suggest similar PFS and OS in the pegfilgrastim and placebo pts in this CRC study.

[Table: see text]

[Table: see text]

Platelet FcgammaRIIA His131Arg polymorphism and platelet function: antibodies to platelet-bound fibrinogen induce platelet activation

The His131Arg polymorphism of platelet FcgammaRIIA affects the binding affinity of certain IgG subclasses. The Arg131 allele has been associated with (auto)immune thrombocytopenia and heparin-induced thrombocytopenia in some studies. Because FcgammaRIIA can transmit platelet activation signals, we studied platelet responsiveness from 73 healthy donors to determine if this polymorphism modulated platelet function. Platelet function was studied by agonist and shear-induced activation, and standard aggregation. FcgammaRIIA was genotyped by allele-specific PCR. Compared with His131, the Arg131 allele was associated with significantly greater binding of activation-dependent antibodies. This effect was most prominent for the receptor-induced binding site (RIBS) antibodies F26 (P < 0.0001) and RIBS1 (P = 0.0057), and the ligand-induced binding site antibody LIBS1 (P = 0.0367). Unexpectedly, Arg131-positive platelets did not show greater fibrinogen binding, platelet aggregation or shear-induced platelet activation. We considered whether enhanced Fc binding and FcgammaRIIA cross-linking were responsible for those discrepancies. The increased binding of the two RIBS antibodies to the Arg131 isoform was abolished by blocking FcgammaRIIA, and the FcgammaRIIA genotype effect on F26 IgG binding was lost when F26 F(ab')2 fragments were used. Furthermore, intact F26 and RIBS1 IgG directly and specifically induced P-selectin expression, and this effect was greatest in Arg131-positive platelets. We concluded that (a) the His131Arg polymorphism of FcgammaRIIA does not affect intrinsic platelet reactivity; (b) RIBS antibodies are able to cross-link FcgammaRIIA and activate platelets, and this activation has a modest effect on Arg131 platelets; and (c) flow cytometric based platelet assays may need to compensate for this FcgammaRIIA His131Arg effect on platelet activation.

Search for a W' boson via the decay mode W'-->munumu in 1.8 TeV pp collisions

We report the results of a search for a W' boson produced in pp collisions at a center-of-mass energy of 1.8 TeV using a 107 pb-1 data sample recorded by the Collider Detector at Fermilab. We consider the decay channel W'-->&munumu and search for anomalous production of high transverse mass munumu lepton pairs. We observe no excess of events above background and set limits on the rate of W' boson production and decay relative to standard model W boson production and decay using a fit of the transverse mass distribution observed. If we assume standard model strength couplings of the W' boson to quark and lepton pairs, we exclude a W' boson with invariant mass less than 660 GeV/c2 at 95% confidence level.

Laparoscopic ureterolithotomy: the Edinburgh experience

OBJECTIVE

To review our experience with laparoscopic ureterolithotomy.

PATIENTS AND METHODS

Since 1993, we have performed laparoscopic ureterolithotomy in 14 patients with ureteric stones. Laparoscopy was carried out in nine patients as a salvage procedure after failed ureteroscopy (six), shock wave lithotripsy (two), or both (one), and in five patients as a primary procedure for large stones (mean 27.2 mm, range 18-40). Patients in the former group had already undergone a mean of 1.88 procedures (range 1-4). Laparoscopic ureterolithotomy was carried out via a transperitoneal approach. Associated ureteric strictures were incised at the time of ureterotomy.

RESULTS

All procedures were completed laparoscopically and all patients were rendered stone-free after a single procedure. The mean operative duration was 105 min. Ureteric strictures were incised in three patients, in two of whom dilatation was subsequently required; all three had a successful result. There were three minor complications.

CONCLUSIONS

Laparoscopic ureterolithotomy can be a safe and effective procedure; it should be considered as a primary procedure for large mid- and upper ureteric stones.

Electrokinetic lithotripsy: safety, efficacy and limitations of a new form of ballistic lithotripsy

OBJECTIVE

To investigate the safety and efficacy of electrokinetic lithotripsy (EKL), a ballistic lithotripter which uses high-energy magnetic fields to propel an impactor to fragment calculi.

PATIENTS AND METHODS

The records and radiographs of 121 patients who underwent ureteroscopy using the EKL for stones in the upper (26), mid (28) or lower (67) ureter were reviewed retrospectively. Ureteroscopy was performed with an 8.5 F semi-rigid ureteroscope, through which a 3 F EKL probe was passed.

RESULTS

A total of 148 stones (mean stone size 11.5 mm, range 6-40) in 121 patients were treated using the EKL. One patient was lost to follow-up. Of 148 stones, 147 (99.3%) were fragmented, including five that had resisted fragmentation with either pulsed-dye laser or electrohydraulic lithotripsy. Despite this, only 45 of 56 patients (80%) with a single stone in the lower ureter were rendered stone-free after a single ureteroscopic procedure. Seven patients in this group (12%) required shock-wave lithotripsy for fragments that had been propelled into the kidney, while four patients (7%) required repeat ureteroscopy for retained ureteric fragments. Complications were limited to minor ureteric perforations in two patients, both of which were treated with a stent.

CONCLUSION

EKL is an inexpensive and reliable endoscopic method which fragments nearly all urinary calculi. Its limitations include the propulsion of fragments and the need to use an offset, semi-rigid ureteroscope. We recommend the use of a basket or graspers to remove fragments of >/=4 mm after EKL.

De novo expression of P-glycoprotein associated with poor prognosis in high grade non-Hodgkin's lymphoma

Chemotherapy has proven to be effective in the management of high grade non-Hodgkin's lymphoma (NHL). However drug resistance remains a major clinical obstacle to effective disease control. One such well documented system involves multidrug resistance (MDR), characterized by the overexpression of a 170 kDa membrane protein termed P-glycoprotein (Pgp). Analysis of P-glycoprotein was done on lymph node biopsies obtained from 109 patients with high grade NHL. Patients were followed up for time periods ranging from 7 to 26 months after chemotherapy or until recurrent/residual disease was diagnosed. Analysis of Pgp in tissue samples was carried out by immunocytochemistry and Western blot. Of the 109 patients, 36 had either residual or recurrent disease. All these patients had a second lymph node biopsy done which was also analyzed for Pgp. P-glycoprotein was detected by immunocytochemistry in only 5 of the 73 patients who remained disease-free, while it was expressed in 26 of the 36 patients with residual/recurrent disease. All the 36 tissue samples of the latter group and 42 of the 73 biopsies of the disease-free group were re-analyzed by Western blot. Only one of the 42 samples from the disease-free group showed a positive Western blot reaction while 30 of the 36 samples from patients with recurrent/residual disease gave a positive reaction. Thirty-four of the 36 repeat biopsy samples from patients with recurrent/residual disease were positive for Pgp. Correlation analysis, thus showed significant relationship between prognosis and detection of Pgp by immunocytochemistry (r=0.85, p<0.001) and Western blot (r=0.90, p<0.001). Moreover, the odds ratio of a tumor positive for Pgp not responding to chemotherapy was 35.36 (CI 11.03, 113.37). Thus evaluation for Pgp may prove to be a useful prognostic marker for high grade NHL, and may also prove useful in designing or altering chemotherapy protocols in such patients.

Tumor proliferative compartment, multidrug resistance gene product and apoptosis regulatory p53 and bcl-2 proteins in pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most frequent childhood tumor. Although the cure rate has increased dramatically over the past few years, the molecular and cellular biology of this disease is still not fully understood. Important factors affecting prognosis include age, leucocyte count, cytogenetic abnormalities, immunophenotype and sex. However, the role of cell kinetics, tumor associated genes and drug resistance have rarely been investigated in pediatric ALL. This preliminary study looks at these aspects in this disease. Immunocytochemical analysis of the tumor suppressor protein p53, the anti apoptotic protein bcl-2, the multidrug resistance (MDR) gene product P-glycoprotein and the proliferation marker, Ki-67 were done using appropriate monoclonal antibodies. A total of 88 previously untreated children with confirmed ALL diagnosis and 40 age matched controls were included in the study. Ki-67 was expressed in 81% and P-glycoprotein in 68% of all cases. P53 expression was observed in 68% and Bcl-2 in 50% of cases. Fifty percent of all cases also showed concomitant expression of bcl-2 and p53. Since wild-type p53 is known to negatively regulate the expression of bcl-2, the co-expression of these two proteins having contrasting functions suggests that the p53 may be of a mutant variety. In addition, the expression of p53 also correlates to the presence of the multidrug gene product P-glycoprotein. Control samples were negative for all the four markers. P53, bcl-2 and P-glycoprotein can all influence chemotherapy resistance, the first two by regulating programmed cell death and the third by influencing intracellular drug levels. All patients are now being followed up to assess treatment response and to study the prognostic significance of the analyzed markers.