Prospectively Tested Research Articles

Evaluation of a BioFire multiplex PCR panel for detection of joint infections using retrospective and prospectively collected specimens.

The BioFire Joint Infection Panel (JI panel) is a newly FDA-approved multiplex PCR assay for detection of common bone and joint pathogens with 39 targets which include select Gram-positive and Gram-negative bacteria, yeast, and antimicrobial resistance genes. We evaluated the performance of the JI panel in detecting joint infections in our patient population. Sixty-three frozen, residual joint fluid specimens were retrospectively tested using the JI panel. An additional 104 residual joint fluid specimens were de-identified and prospectively tested within 1 week of collection. Results from routine bacterial cultures were used as the reference standard, which included inoculation to agar plates and blood culture bottles. For the frozen specimens, the JI panel showed a positive percent agreement (PPA) of 92.8% and a negative percent agreement (NPA) of 97.1%. PPA was 71.4% and NPA was 94.8% for fresh specimens. A total of 12 discrepancies were observed among the 167 specimens tested. The JI panel demonstrated good overall agreement with routine culture for the detection of joint infections and may improve timely diagnosis when used in conjunction with bacterial culture. However, potential false-positive and false-negative results were observed in both retrospective and prospective testing of specimens.IMPORTANCEThe BioFire JI panel is a new commercially available multiplex PCR assay for detecting common pathogens causing bone and joint infections. The test is performed directly on joint fluids with a fast turnaround time of 1 hour. Our study shows that while the JI panel overall shows good agreement with routine culture, discrepancies were observed in 7% of cases and results should be interpreted with appropriate clinical context.

Intelligent ultrafast total-body PET for sedation-free pediatric [18F]FDG imaging.

This study aims to develop deep learning techniques on total-body PET to bolster the feasibility of sedation-free pediatric PET imaging. A deformable 3D U-Net was developed based on 245 adult subjects with standard total-body PET imaging for the quality enhancement of simulated rapid imaging. The developed method was first tested on 16 children receiving total-body [18F]FDG PET scans with standard 300-s acquisition time with sedation. Sixteen rapid scans (acquisition time about 3 s, 6 s, 15 s, 30 s, and 75 s) were retrospectively simulated by selecting the reconstruction time window. In the end, the developed methodology was prospectively tested on five children without sedation to prove the routine feasibility. The approach significantly improved the subjective image quality and lesion conspicuity in abdominal and pelvic regions of the generated 6-s data. In the first test set, the proposed method enhanced the objective image quality metrics of 6-s data, such as PSNR (from 29.13 to 37.09, p < 0.01) and SSIM (from 0.906 to 0.921, p < 0.01). Furthermore, the errors of mean standardized uptake values (SUVmean) for lesions between 300-s data and 6-s data were reduced from 12.9 to 4.1% (p < 0.01), and the errors of max SUV (SUVmax) were reduced from 17.4 to 6.2% (p < 0.01). In the prospective test, radiologists reached a high degree of consistency on the clinical feasibility of the enhanced PET images. The proposed method can effectively enhance the image quality of total-body PET scanning with ultrafast acquisition time, leading to meeting clinical diagnostic requirements of lesion detectability and quantification in abdominal and pelvic regions. It has much potential to solve the dilemma of the use of sedation and long acquisition time that influence the health of pediatric patients.

Development and validation of a model to calculate anesthetic agent consumption from inspired and end-expired concentrations, minute ventilation, fresh gas flow and dead space ventilation.

Anesthetic agent consumption is often calculated as the product of fresh gas flow (FGF) and vaporizer dial setting (FVAP). Because FVAP of conventional vaporizers is not registered in automated anesthesia records, retrospective agent consumption studies are hampered. The current study examines how FVAP can be retrospectively calculated from the agent's inspired (FIN) and end-expired concentration (FET), FGF, and minute ventilation (MV). Theoretical analysis of agent mass balances in the circle breathing reveals FVAP = [FIN - (dead space fraction * FIN + (1 - dead space fraction) * FET) * (1 - FGF/MV)]/(1-(1 - FGF/MV)). FIN, FET, FGF and MV are routinely monitored, but dead space fraction is unknown. Dead space fraction for sevoflurane, desflurane, and isoflurane was therefore determined empirically from an unpublished data set of 161 patient containing FVAP, FIN, FET, MV and FGF ranging from 0.25 to 8 L/min delivered via an ADU® (GE, Madison, WI, USA). Dead space fraction for each agent was determined empirically by having Excel's solver function calculate the value of dead space fraction that minimized the sum of the squared differences between dialed FVAP and predicted FVAP. With dead space fraction known, the model was then prospectively tested for sevoflurane in O2/air using data collected over the course of two weeks with one FLOW-i (Getinge, Solna, Sweden) and one Zeus workstation (Dräger, Lübeck, Germany). Because both workstations use an electronically controlled vaporizer/injector, the dialed FVAP were available to allow the calculation of median performance error (MDPE) and median absolute performance error (MDAPE). MDPE and MDAP are reported as median and interquartiles. The empirical dead space fraction for isoflurane, sevoflurane, and desflurane were 0.59, 0.49, and 0.66, respectively. For prospective testing, a total of 149.4h of useful data were collected from 78 patient with the Zeus and Flow-i combined, with FGF ranging from 0.18 to 8 L/min. The model predicted dialed FVAP well, with a MDPE of -1 (-11, 6) % and MDAPE of 8 (4, 17) %. FVAP can be retrospectively calculated from FIN, FET, FGF, and MV plus an agent specific dead space fraction factor with a degree of error that we believe suffices for retrospective sevoflurane consumption analyses. Performance with other agents and N2O awaits further validation.

Abstract PS5-11: Prospective HER-2 testing using simultaneous immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH): Experience of dual testing in a single academic institution

Abstract Background: HER-2 testing informs prognosis and critically guides therapy in breast cancer. Current guidelines for immunohistochemistry (IHC) testing define 3+ as positive, 0 and 1+ as negative, and 2+ as equivocal with additional testing recommended. Guidelines for in situ hybridization (ISH) testing are more complex and generally define a HER-2/CEP17 ratio of ≥2.0 with average HER-2 copy number of ≥4.0 copies/cell as HER-2 positive. Further, HER-2 copy number between 4 and 6 per cell, with a ratio of &amp;lt;2.0, is considered equivocal while &amp;gt;6 per cell is frequently confirmed positive. Limited data suggest that an elevated HER-2 copy number alone has clinical relevance, however most clinical trials addressing HER-2 targeted therapeutics define HER-2 positive based on HER-2/CEP17 ≥2.0. Design: From 2013-2016, all new invasive breast cancer cases diagnosed at the University of Vermont Medical Center were prospectively tested for HER-2 using both IHC and chromogenic in situ hybridization (CISH) simultaneously. All testing was performed on formalin-fixed paraffin-embedded tissue, using the 4B5 Rabbit Monoclonal Antibody (Ventana) for IHC and the INFORM dual ISH DNA probe (Ventana) for CISH. Interpretation was performed using published criteria, and all cases were independently analyzed by two experienced reviewers. Results: 1906 patients underwent HER-2 testing by both IHC and CISH. 1671 (87.7%) patients had a HER-2/CEP17 ratio of &amp;lt;2.0. Of patients considered to be non-amplified by the CISH ratio, 55 (3.2%) had a HER-2 copy number &amp;gt;4. In IHC 0 and 1+ cases with HER-2/CEP17 ratio of &amp;lt;2, 0.4% and 2.3% have equivocal and excess HER-2 copies/cell, respectively, compared to 10.8% for IHC 2+. Additionally, 17 (8.6%) of the IHC 3+ cases had a CISH ratio of &amp;lt;2, of which 41.2% had &amp;gt;4 HER-2 copies/cell (see table). Conclusion: To our knowledge, this is the largest study to date that has examined the concurrent use of both IHC and ISH HER-2 assays prospectively in a real-time clinical setting. In the IHC 2+ cohort, only 12.5% were amplified by ISH testing. Interestingly, of those in the IHC 2+ cohort not amplified by CISH, 10.8% had an equivocal or excess HER-2 copy number. Further, while based on a very small sample size, 41.2% of IHC 3+ patients with a CISH ratio of &amp;lt;2.0 had an equivocal or excess HER-2 average copy number. Finally, data on the clinical outcome and therapeutic benefit of HER-2 targeted therapy in patients with non-amplified ISH testing and equivocal or excess HER-2 copy number remains limited, and warrants further evaluation. Table. Simultaneously tested IHC and CISH data for new invasive breast cancer casesIHCCISH ratio ≥2.0CISH ratio &amp;lt;2.0HER-2 copies/cell (CISH ratio &amp;lt;2.0 cohort)CISH ratio &amp;lt;2.0 with ≥4 HER-2 copies/cellIHCnn (%)n (%)&amp;lt;4 (n)4-6 (n)&amp;gt;6 (n)05010 (0.0)501 (100.0)499200.4%1+94221 (2.2)921 (97.8)8992012.3%2+26533 (12.5)232 (87.5)20625010.8%3+198181 (91.4)17 (8.6)106141.2%Total1906235 (12.3)1671 (87.7)16145323.2% Citation Format: Kara K Landry, Abiy B Ambaye, Donald L Weaver, Peter A Kaufman. Prospective HER-2 testing using simultaneous immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH): Experience of dual testing in a single academic institution [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS5-11.

Development and Verification of a Digital Twin Patient Model to Predict Specific Treatment Response During the First 24 Hours of Sepsis.

Directed acyclic graphs were used to define explicitly the causal relationship among organ systems and specific treatments used. A hybrid approach of agent-based modeling, discrete-event simulation, and Bayesian network was used to simulate treatment effect across multiple stages and interactions of major organ systems (cardiovascular, neurologic, renal, respiratory, gastrointestinal, inflammatory, and hematology). Organ systems were visualized using relevant clinical markers. The application was iteratively revised and debugged by clinical experts and engineers. Agreement statistics was used to test the performance of the model by comparing the observed patient response versus the expected response (primary and secondary) predicted by digital twin. Medical ICU of a large quaternary- care academic medical center in the United States. Adult (> 18 year yr old), medical ICU patients were included in the study. No additional interventions were made beyond the standard of care for this study. During the verification phase, model performance was prospectively tested on 145 observations in a convenience sample of 29 patients. Median age was 60 years (54-66 d) with a median Sequential Organ Failure Assessment score of 9.5 (interquartile range, 5.0-14.0). The most common source of sepsis was pneumonia, followed by hepatobiliary. The observations were made during the first 24 hours of the ICU admission with one-step interventions, comparing the output in the digital twin with the real patient response. The agreement between the observed versus and the expected response ranged from fair (kappa coefficient of 0.41) for primary response to good (kappa coefficient of 0.65) for secondary response to the intervention. The most common error detected was coding error in 50 observations (35%), followed by expert rule error in 29 observations (20%) and timing error in seven observations (5%). We confirmed the feasibility of development and prospective testing of causal artificial intelligence model to predict the response to treatment in early stages of critical illness. The availability of qualitative and quantitative data and a relatively short turnaround time makes the ICU an ideal environment for development and testing of digital twin patient models. An accurate digital twin model will allow the effect of an intervention to be tested in a virtual environment prior to use on real patients.

Prospective testing of a neurophysiologic biomarker for treatment decisions in major depressive disorder: The PRISE-MD trial

Management of Major Depressive Disorder (MDD) might be improved by a biomarker to predict whether a selected medication is likely to lead to remission. We previously reported on a quantitative electroencephalogram-based biomarker, the Antidepressant Treatment Response (ATR) index, that integrated recordings at baseline and after one week of treatment. The present study prospectively tested whether treatment directed by the biomarker increased the likelihood of remission; we hypothesized that continued treatment with a drug predicted to lead to remission (i.e., high ATR values) would be associated with better outcomes than if the drug was predicted not to lead to remission (i.e., low ATR values). We enrolled 180 adult outpatients with unipolar MDD from the community. After one week of escitalopram treatment to determine the biomarker, stratified randomization (high vs. low ATR) was used to assign subjects to either continued escitalopram or a switch to bupropion as a blinded control condition, for seven additional weeks. For the 73 evaluable subjects assigned to continued escitalopram treatment, the remission rate was significantly higher for those in whom ATR had predicted remission versus non-remission (60.4% vs. 30.0%, respectively, p = 0.01). Accuracy was enhanced by combining 1-week depressive symptom change with ATR (68.6% vs 28.9%). This prospective validation study supports further development of the ATR biomarker, alone or together with early symptom change, to improve care by identifying individuals unlikely to remit with their current treatment, and support the decision to change treatment after one week rather than after failing a full, prolonged course of medication.

648P - Feasibility and impact of prospective DPYD screening in the Irish population

BackgroundGenetic variants of dihydropyrimidine dehydrogenase (DPYD) gene can result in varied enzymatic activity and potential toxicity when receiving 5-FU chemotherapy including treatment related death in up to 1% patients. Current international guidelines suggest an international rate of 3-5% albeit routine prospective pharmacogenomic testing is not currently recommended. However, in a genetically homogenous population such as Ireland, DPYD variant enrichment may support routine testing. MethodsAll patients receiving 5-FU based chemotherapy in South & South-West region of Ireland were prospectively tested from 01/09/2018 to present. The Viapath DPYD genotyping panel which interrogates for 5 variants was used. Toxicity type and grade for all patients were recorded (CTCAE v5.0). ResultsTo date, 139 patients have been tested,50.4% male and 49.6% female, median age 63 years. The majority(59%) were being treated for colorectal cancer. Sixteen patients were found to be heterozygous carriers of a DYPD variant with one compound heterozygous variant identified i.e. an overall prevalence of 12 %. No homozygous carriers were identified. Grade ≥3 was observed in 33% DPYD variant carriers compared to 19% in DPYD wild type patients i.e. relative risk of grade ≥3 toxicity is 1.7, p=0.17.Table648PTableDPYD VariantsPrevalence % n=139% Rate of ≥ G3 toxicity7(5.0%)42%c. 2846A>T1(0.7%)n/a*c. 1905+1G>A3(2.2%)100%c. 1679T>G0 (0%)n/a*c. 1601GA5 (3.6%)0%c. 1905+1G>A+c;1236G>A/Hapb3 compound heterozygous1(0.7%)n/a*TOTAL:17 (12.2%) ConclusionsThe study shows a higher than expected prevalence of DPYD variants of 12.2% compared to internationally reported 3-5%. Patients with DPYD variants c.1236G>A and c.1905+1G>A were particularly likely to develop Grade ≥ 3 toxicity. Prospective testing continues to assess the clinical relevance of individual variants in our population.Legal entity responsible for the study: The authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Adult Tourniquet for Use in School-Age Emergencies.

Gunshot injuries are a leading cause of morbidity and mortality in the pediatric population. The Pediatric Trauma Society supports the use of tourniquets for exsanguinating hemorrhage in severe extremity trauma. The Combat Application Tourniquet (CAT) used with success in adults has not been prospectively tested in children. Our objective with this study was to determine if the CAT is successful in arresting extremity arterial blood flow in school-aged children. Sixty school-aged volunteers (ages 6-16 years) recruited by age cohort had the CAT applied to an upper arm and thigh while peripheral pulse was monitored by Doppler. The number of windlass turns (maximum allowed: 3 [1080°]) required to arrest arterial pulse was recorded. Success was analyzed by BMI percentile for age and extremity circumference. The CAT was successful in occluding arterial blood flow as detected by Doppler pulse in all 60 (100%) of the upper extremities tested. In the lower extremity, 56 (93%) had successful occlusion. The 3-turn maximum allowed by the protocol was not adequate in some obese, older subjects (BMI >30). In both the upper and lower extremity, the number of turns required to occlude blood flow gradually increased with an increase in arm and thigh circumference. Prospective testing of a cohort of school-aged children 6 to 16 years revealed the CAT tourniquet to be suitable for use in both the upper and lower extremity.

Methylchloroisothiazolinone/Methylisothiazolinone and Methylisothiazolinone Sensitivity in Hungary.

Background. Due to allowing of methylisothiazolinone (MI) in cosmetics, cleaning products, and paints, an epidemic of MI-hypersensitivity emerged. Patch testing Kathon CG® (3:1 mixture of methylchloroisothiazolinone and methylisothiazolinone, MCI/MI) does not correctly detect MI contact allergy, due to the low concentration of MI in the test material. Methods. A retrospective survey was performed to estimate the prevalence of MCI/MI hypersensitivity in 14693 patients tested consecutively between 1993 and 2014. Moreover, currently 314 patients were prospectively tested with the allergens MCI/MI and with MI during one year. Results. MCI/MI hypersensitivity increased retrospectively from 0.5% to 6.0%. By current prospective testing we detected 25 patients (8%) with MCI/MI and/or MI positive reactions. Out of the 25 patients 10 were only MCI/MI positive, 9 were only MI positive, and 6 were MCI/MI and MI positive. If MI had not been tested separately, MI contact allergy would have missed in 36% of all detected cases and in 2.8% of the total 314 patients. Conclusions. The frequency of MCI/MI hypersensitivity is increasing also in Hungary. We confirm that, in order to detect MI contact allergy, it needs to be tested separately. A further increase of MI hypersensitivity might be expected in the future as products containing MI are still widely available.

Methotrexate and temozolomide versus methotrexate, procarbazine, vincristine, and cytarabine for primary CNS lymphoma in an elderly population: an intergroup ANOCEF-GOELAMS randomised phase 2 trial

No standard chemotherapy regimen exists for primary CNS lymphoma, reflecting an absence of randomised studies. We prospectively tested two promising methotrexate-based regimens, one more intensive and a milder regimen, for primary CNS lymphoma in the elderly population, who account for most patients. In this open-label, randomised phase 2 trial, done in 13 French institutions, we enrolled immunocompetent patients who had neuroimaging and histologically confirmed newly diagnosed primary CNS lymphoma, were aged 60 years and older, and had a Karnofsky performance scale score of 40 or more. Participants were stratified by Karnofsky performance scale score (<60 vs ≥60) and treating institution and randomly assigned (1:1) to receive methotrexate (3·5 g/m(2)) with temozolomide (150 mg/m(2)) or methotrexate (3·5 g/m(2)), procarbazine (100 mg/m(2)), vincristine (1·4 mg/m(2)), and cytarabine (3 mg/m(2)). Neither regimen included radiotherapy; both included prophylactic G-CSF and corticosteroids. The primary endpoint was 1-year progression-free survival. Analysis was intent to treat, in a non-comparative phase 2 trial design. This study is registered with ClinicalTrials.gov, number NCT00503594. Between July 16, 2007, and March 25, 2010, 98 patients were enrolled, of whom 95 were randomly assigned and analysed; 48 to methotrexate with temozolomide and 47 to methotrexate, procarbazine, vincristine, and cytarabine. 1-year progression-free survival was 36% (95% CI 22-50) in the methotrexate, procarbazine, vincristine, and cytarabine group and 36% (22-50) in the methotrexate with temozolomide group; median progression-free survival was 9·5 months (95% CI 5·3-13·8) versus 6·1 months (3·8-11·9), respectively. Objective responses were noted in 82% (95% CI 68-92) of patients in the methotrexate, procarbazine, vincristine, and cytarabine group versus 71% (55-84) of patients in the methotrexate with temozolomide group. Median overall survival was 31 months (95% CI 12·2-35·8) in the methotrexate, procarbazine, vincristine, and cytarabine group and 14 months (8·1-28·4) in the methotrexate with temozolomide group. No differences were noted in toxic effects between the two groups. The most common grades 3 and 4 toxicities in both groups were liver dysfunction (21 [4%] in the the methotrexate and temozolomide group and 18 [38%] in the methotrexate, procarbazine, vincristine, and cytarabine group), lymphopenia (14 [29%] and 14 [30%]), and infection (six [13%] and seven [15%]). To date, 33 (69%) patients in the methotrexate and temozolomide group have died, versus 31 (55%) in the methotrexate, procarbazine, vincristine and cytarabine group. Quality-of-life evaluation (QLQ-C30 and BN20) showed improvements in most domains (p=0·01-0·0001) compared with baseline in both groups. Prospective neuropsychological testing showed no evidence of late neurotoxicity. In this study of two different methotrexate-based combination regimens in elderly patients, the efficacy endpoints tended to favour the methotrexate, procarbazine, vincristine, and cytarabine group. Both regimens were associated with similar, moderate toxicity, but quality of life improved with time, suggesting pursuing treatment in these poor prognosis patients is worthwhile. New alternatives are needed to improve response duration in this population. Schering-Plough/Merck and French Government.

Prospective testing of mucoepidermoid carcinoma for the MAML2 translocation: Clinical Implications

Mucoepidermoid carcinoma (MEC) with MAML2 translocation is believed to be associated with lower clinical stage, lower histologic grade, and better outcome. We summarized our prospective experience testing MEC for the MAML2 translocation. Prospective cohort study. One hundred eighteen head and neck tumors (55 MECs and 63 mimics) were prospectively tested for MAML2 translocation by fluorescence in situ hybridization as part of clinical care during a 36-month period. MAML2 translocation was identified in 41 of 55 (75%) cases diagnosed as MEC. Translocation status did not correlate significantly with histologic grade, age, gender, tumor site, or T stage. Routine testing for MAML2 translocation by fluorescence in situ hybridization is feasible and useful in confirming the diagnosis of MEC. The lack of significant correlation with histologic grade or pathologic stage implies that the previously reported prognostic value of the MAML2 translocation may be an artifact of misclassification of MEC as other tumors.

Relation of Routine, Periodic Fasting to Risk of Diabetes Mellitus, and Coronary Artery Disease in Patients Undergoing Coronary Angiography

Previously we discovered that routine periodic fasting was associated with a lower prevalence of coronary artery disease (CAD). Other studies have shown that fasting increases longevity in animals. A hypothesis-generating analysis suggested that fasting may also associate with diabetes. This study prospectively tested whether routine periodic fasting is associated with diabetes mellitus (DM). Patients (n = 200) undergoing coronary angiography were surveyed for routine fasting behavior before their procedure. DM diagnosis was based on physician reports of current and historical clinical and medication data. Secondary end points included CAD (physician reported for ≥ 1 lesion of ≥ 70% stenosis), glucose, and body mass index (BMI). Meta-analyses were performed by evaluation of these patients and 448 patients from a previous study. DM was present in 10.3% of patients who fasted routinely and 22.0% of those who do not fast (odds ratio [OR] 0.41, 95% confidence interval [CI] 0.17 to 0.99, p = 0.042). CAD was found in 63.2% of fasting and 75.0% of nonfasting patients (OR 0.42, CI 0.21 to 0.84, p = 0.014), and in nondiabetics this CAD association was similar (OR 0.38, CI 0.16 to 0.89, p = 0.025). Meta-analysis showed modest differences for fasters versus nonfasters in glucose concentrations (108 ± 36 vs 115 ± 46 mg/dl, p = 0.047) and BMI (27.9 ± 5.3 vs 29.0 ± 5.8 kg/m(2), p = 0.044). In conclusion, prospective hypothesis testing showed that routine periodic fasting was associated with a lower prevalence of DM in patients undergoing coronary angiography. A reported fasting association with a lower CAD risk was also validated and fasting associations with lower glucose and BMI were found.

Prediction of Response and Prognosis by a Score Including Only Pretherapeutic Parameters in 410 Neoadjuvant Treated Gastric Cancer Patients

Response to neoadjuvant chemotherapy is an independent prognostic factor in locally advanced gastric cancer. However, no prospectively tested pretherapeutic parameters predicting response and/or survival in gastric cancer are available in clinical routine. We evaluated the prognostic significance of various clinical pathologic parameters in 410 patients who were treated with neoadjuvant chemotherapy followed by gastrectomy. Clinical and histopathologic response evaluation was performed by using standardized criteria. A prognostic score was created on the basis of the variables identified in the multivariate analysis. Three pretherapeutic parameters were identified as positive predictive factors for response and prognosis: tumor localization in the middle third of the stomach (P=0.001), well-differentiated tumors (P=0.001), and intestinal tumor type according to Laurén classification (P=0.03). A prognostic index was constructed, dividing the patients into three risk groups: low (n=73), intermediate (n=274), and high (n=63). The three groups had significantly different clinical (P=0.007) and histopathologic response rates (P=0.001) and survival times, with a median survival time that was not reached in the low-risk group, 39.2 months in the intermediate-risk group, and 20.5 months in the high-risk group. The corresponding 5-year survival rates were 65.3, 41.2, and 21.2% (P<0.001), respectively. A simple scoring system based on three clinicopathologic parameters accurately predicts response and prognosis in neoadjuvant treated gastric cancer. This system provides additional useful information that could be applied to select gastric cancer patients pretherapeutically for different treatment approaches. Prospective testing of the score in an independent patient cohort is warranted.

Prediction of response and prognosis by a score including only pretherapeutic parameters in 410 neoadjuvant treated gastric cancer patients.

4037 Background: Response to neoadjuvant chemotherapy is an independent prognostic factor in locally advanced gastric cancer. However, no prospectively tested pretherapeutic parameters predicting response and/or survival in gastric cancer are available in clinical routine so far. Methods: We evaluated the prognostic significance of various clinicopathologic parameters in 410 patients who were treated with neoadjuvant chemotherapy followed by gastrectomy. Clinical and histopathological response evaluation was performed using standardized criteria. A prognostic score was created on the basis of the variables identified in the multivariate analysis. Results: Three pretherapeutic parameters were identified as positive predictive factors for response and prognosis by multivariate analysis: tumor localization in the middle (p=0.001), well differentiated tumors (p=0.001) and intestinal tumor type according to Laurén’s classification (p=0.03). A prognostic index was constructed, dividing the patients into three risk groups: low (n=73), intermediate (n=274) and poor (n=63). The three groups had significantly different clinical (p=0.007) and histopathological response rates (p=0.001) and survival times, with a median survival for the low, intermediate and poor risk groups being not reached, 39.3 and 20.5 months, and the corresponding 5 year survival rates being 65.3%, 41.2%, 21.2% (p<0.001), respectively. Conclusions: A simple scoring system based on three clinicopathologic parameters accurately predicts response and prognosis in neoadjuvant treated gastric cancer. This system provides additional useful information that could be applied to select gastric cancer patients pretherapeutically for different treatment approaches. Prospective testing of the score in an independent patient cohort is warranted.

Detection of novel genetic aberrations in salivary duct carcinoma (SDC) by SNaPshot analysis.

5579 Background: Salivary gland cancers (SGCs) are rare and heterogeneous malignancies, with SDC being one of the more aggressive subtypes. Establishing effective therapy for SGCs is challenging given their rarity and heterogeneity. Cytotoxic chemotherapy has limited efficacy, and of the targeted therapies that have been studied, few objective responses have been seen. It is clear that disease management with targeted agents is most effective when directed by tumor genotype. To address this need, we utilized a clinical test, SNaPshot, designed to detect tumor-specific mutations to help direct treatment of SDC with targeted therapies. Methods: 24 SDC specimens were genotyped. These included 7 patients seen at the Massachusetts General Hospital Cancer Center who were prospectively tested. The SNaPshot assay uses DNA extracted from FFPE tissue and was designed to detect sequence variants in a panel of 14 clinically-relevant cancer genes. FISH was used to detect HER2 gene amplification. Retrospective review of clinical charts and of tumor pathological features was performed. Results: Mutually exclusive genetic aberrations were detected in 13 of 24 (54%) tumors, including 2 mutations in BRAF(8%), 4 mutations in PIK3CA (16%), and 7 cases of HER2 amplification (29%). Prospective clinical testing of 7 SDC identified mutations in 4 tumors, and influenced therapeutic decisions for 3 patients: 1 patient with a BRAF mutation enrolled on a phase I study of GSK1120212 + GSK118436, and experienced a near complete response lasting > 6 months; 1 with a PIK3CA mutation was enrolled on a phase I study of a PI3 kinase inhibitor; and 1 with HER2 amplification received trastuzumab with adjuvant chemoradiotherapy. Given the cohort size, statistical analysis was limited, with no significant correlations being found between genotype and pathologic features or survival. Conclusions: SNaPshot genetic profiling identified novel genetic changes in SDCs, expanded the therapeutic options for patients with this rare tumor, and is changing SDC management at our institution. These findings highlight the importance of using broad genetic profiling to expedite the identification of effective targeted therapies for patients with rare malignancies.

Abstract P6-14-06: Prospective Testing of Three Different Gene-Signatures for Patient Selection for Dasatinib Therapy in Metastatic Breast Cancer

Abstract Background: Several gene signature-based predictors of response to targeted drugs have been proposed in the literature but none has been prospectively tested as patient selection tools in the clinic. The goal of this trial is to assess the positive predictive value of 3 conceptually different multi-gene signatures as predictors of response to the multitargeted kinase inhibitor dasatinib. Methods: This clinical trial requires biopsy of a metastatic lesion for gene expression profiling and employs a parallel, multi-arm, two-step, phase II design. Three markers are assessed including a (i) cell-line derived dasatinib-sensitivity signature, (ii) a src-pathway activity signature and (iii) a dasatinib target index calculated as the weighted average expression of all known dasatinib targets. Only markerpositive patients are treated with dasatinib 100 mg po daily and each marker arm is considered as a separate study with early stopping rules for futility (minimum sample size 9, maximum sample size 40/marker arm). A predictor is considered worthy of further study if the clinical benefit rate (i.e. positive predictive value) is ≥25%. Results: Forty seven patients were accrued from July 2009 through June, 2010, 49 biopsies were performed (soft tissues n=31, liver n=8, bone n=3, lung n=1, adrenal gland n=1), 6 samples had poor cellularity and 3 failed array QC. There was no patient recall, hospitalization or emergency room visit due to biopsy procedure. The median time from biopsy to genomic prediction result was 5 days (range 3-7). Twenty three (57%) patients had positive result for at least 1 predictor (5 were positive for 2) and 20 are receiving therapy (3 withdraw or progressed before therapy began). Responses as of June 2010; Target index arm (n=9): 5 PD (progressive disease), 4 SD (3 stable disease at 8 weeks 1 SD at 16 weeks); SRC Pathway arm (n=5): 3 PD, 2 SD at 8 weeks; Cell line predictor arm (n=6): 2 PD, 1 SD at 8 weeks, 3 not yet reached response evaluation. None of the 3 predictive marker arms have met early stopping yet and accrual is ongoing. Conclusion: Gene-expression signature based patient selection for targeted therapy is feasible and FNA biopsies of metastatic lesions for genomic testing are safe. Updated efficacy results will be reported. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-14-06.

Derivation and Prospective Testing of a Two-step Sevoflurane-O2-N2O Low Fresh Gas Flow Sequence

Simple vaporiser setting (F(D)) and fresh gas flow (FGF) sequences make the practice of low-flow anaesthesia not only possible but also easy to achieve. We sought to derive a sevoflurane F(D) sequence that maintains the end-expired sevoflurane concentration (F(A)sevo) at 1.3% using the fewest possible number of F(D) adjustments with a previously described O2-N2O FGF sequence that allows early FGF reduction to 0.7 l min(-1). In 18 ASA physical status I to IH patients, F(D) was determined to maintain F(A)sevo at 1.3% with 2 l min(-1) O2 and 4 l min(-1) N2O FGF for three minutes, and with 0.3 and 0.4 l min(-1) thereafter. Using the same FGF sequence, the F(D) schedule that approached the 1.3% F(A)sevo pattern with the fewest possible adjustments was prospectively tested in another 18 patients. The following F(D) sequence approximated the F(D) course well: 2% from zero to three minutes, 2.6% from three to 15 minutes and 2.0% after 15 minutes. When prospectively tested, median (25th; 75th percentile) performance error was 0.8 (-2.9; 5.9)%, absolute performance error 6.7 (3.3; 10.6)%, divergence 18.2 (-5.6; 27.4)%.h(-1) and wobble 4.4 (1.7; 8.1) %. In one patient, FGF had to be temporarily increased for four minutes. One O2/N2O rotameter FGF setting change from 6 to 0.7 l min(-1) at three minutes and two sevoflurane F(D) changes at three and 15 minutes maintained predictable anaesthetic gas concentrations during the first 45 minutes in all but one patient in our study.

Prospective tests on biological models of acupuncture.

The biological effects of acupuncture include the regulation of a variety of neurohumoral factors and growth control factors. In science, models or hypotheses with confirmed predictions are considered more convincing than models solely based on retrospective explanations. Literature review showed that two biological models of acupuncture have been prospectively tested with independently confirmed predictions: The neurophysiology model on the long-term effects of acupuncture emphasizes the trophic and anti-inflammatory effects of acupuncture. Its prediction on the peripheral effect of endorphin in acupuncture has been confirmed. The growth control model encompasses the neurophysiology model and suggests that a macroscopic growth control system originates from a network of organizers in embryogenesis. The activity of the growth control system is important in the formation, maintenance and regulation of all the physiological systems. Several phenomena of acupuncture such as the distribution of auricular acupuncture points, the long-term effects of acupuncture and the effect of multimodal non-specific stimulation at acupuncture points are consistent with the growth control model. The following predictions of the growth control model have been independently confirmed by research results in both acupuncture and conventional biomedical sciences: (i) Acupuncture has extensive growth control effects. (ii) Singular point and separatrix exist in morphogenesis. (iii) Organizers have high electric conductance, high current density and high density of gap junctions. (iv) A high density of gap junctions is distributed as separatrices or boundaries at body surface after early embryogenesis. (v) Many acupuncture points are located at transition points or boundaries between different body domains or muscles, coinciding with the connective tissue planes. (vi) Some morphogens and organizers continue to function after embryogenesis. Current acupuncture research suggests a convergence of the neurophysiology model, the connective tissue model and the growth control model. The growth control model of acupuncture set the first example of a biological model in integrative medicine with significant prediction power.

A prospective test of the dual-pathway model of bulimic pathology: mediating effects of dieting and negative affect.

Because there have been few longitudinal investigations of integrative etiological theories of bulimia nervosa, this study prospectively tested the dual-pathway model using random regression growth curve models and data from a 3-wave community sample of adolescent girls (N = 231). Initial pressure to be thin and thin-ideal internalization predicted subsequent growth in body dissatisfaction, initial body dissatisfaction predicted growth in dieting and negative affect, and initial dieting and negative affect predicted growth in bulimic symptoms. There was prospective evidence for most of the hypothesized mediational effects. Results are consistent with the assertion that pressure to be thin, thin-ideal internalization, body dissatisfaction, dieting, and negative affect are risk factors for bulimic pathology and provide support for the dual-pathway model.

Prospective evaluation of a microprocessor-assisted cardiac rhythm algorithm: Results from one clinical center

A new microprocessor-assisted cardiac rhythm algorithm (MAC-RHYTHM), based on median QRST subtraction from 10-second electrocardiographic (ECG) data, was prospectively tested on 10,761 ECGs acquired at one of three clinical centers. Atrial waves (P waves, atrial fibrillatory waves, and flutter waves) were detected from the median QRST-subtracted residual signals. Rhythm criteria were applied to the detected atrial waves and their temporal relation to QRS complexes for generating rhythm interpretations. Rhythm statements generated by MAC-RHYTHM were compared against the true rhythm of the ECGs as read by an experienced cardiologist. The results of prospective testing were compared with the results of an earlier retrospective testing using MAC-RHYTHM and a released commercial ECG analysis program on stored ECGs. The prospective results were very similar to the results of MAC-RHYTHM on retrospective data for all the rhythms examined (sinus rhythms, atrial fibrillation, atrial flutter, junctional rhythms, second degree atrioventricular blocks). For three of the abnormal rhythms, namely, atrial fibrillation, junctional rhythms, and second degree atrioventricular blocks, MAC-RHYTHM gave significantly higher sensitivity in both prospective (87.5%, 92.2%, and 80.8%, respectively) and retrospective (82.0%, 81.2%, and 79.6% respectively) testing than the released commercial ECG analysis program (65.0%, 39.6%, and 12.0% respectively). Similarly, for sinus rhythms, MAC-RHYTHM had significantly higher specificity (prospective, 91.0% and retrospective, 91.7%) than the released commercial program (86.5%). The specificity for the abnormal rhythms remained very high with MAC-RHYTHM (prospective, 99.4% to 99.7% and retrospective, 99.1% to 99.7%) compared to the released commercial program (99.0% to 99.9%). This prospective study also indicated that further work is needed to improve the detection of pacemaker spikes and the interpretation of paced rhythms in 10-second resting ECGs.