Abstract P4-09-12: Baseline and End-of-Treatment Biomarkers in Patients With PIK3CA-Mutated, Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer From BYLieve Study Cohorts A and B

Introduction: Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) is mutated in ~40% of patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) advanced breast cancer (ABC). PIK3CA mutations are associated with resistance to endocrine therapy (ET) and worse overall survival. Alpelisib (ALP), an α-selective PI3K inhibitor and degrader, is indicated in combination with fulvestrant (FUL) for pts with PIK3CA-mutated (mut) HR+, HER2− ABC following progression on/after ET-based treatments. In the Phase 2, open-label, 3-cohort, noncomparative BYLieve study, clinical benefit of ALP in combination with ET was observed in the post-cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) setting in pts with PIK3CA-mut, HR+, HER2− ABC. Here we report the results of a biomarker analysis using paired baseline (Cycle 1 Day 1) and end-of-treatment (EOT) circulating tumor DNA (ctDNA) samples from pts in BYLieve Cohorts A and B.

Methods: In the BYLieve study, pts with PIK3CA-mut, HR+, HER2− ABC had CDK4/6i + aromatase inhibitor (Cohort A; N=127) or CDK4/6i + FUL (Cohort B; N=126) as treatment immediately prior to receiving ALP + FUL and ALP + letrozole, respectively. In this biomarker analysis, gene alterations were detected in ctDNA at baseline and EOT using next-generation sequencing (PanCancer V2 panel). Pts included in this interim analysis had confirmed PIK3CA mutations and matched baseline/EOT samples with enough sequencing coverage and ctDNA fraction to detect mutations at both time points. ctDNA fractions, tumor mutation burden (TMB) distributions, genomic landscapes, gain/loss of PIK3CA and estrogen receptor 1 (ESR1), chromosome 8/11 amplification profiles, and alterations in PI3K pathway and potential CDK4/6i resistance markers were assessed across time points. Sample sizes were small; results should thus be interpreted with caution.

Results: Forty-three pts were included in the Cohort A biomarker population and 40 pts were included in Cohort B. ctDNA fraction was numerically higher at EOT compared with baseline in both cohorts; further analyses will be presented. In Cohort A, no significant differences were observed in TMB at EOT compared with baseline (P=0.21). In Cohort B, TMB was higher at EOT compared with baseline (P=0.053). Chromosome 8/11 amplifications were consistent between baseline and EOT for both cohorts. Small variations were observed in ESR1/PIK3CA mutations between baseline and EOT on both cohorts (Table). The status of potential CDK4/6i resistance markers was relatively unchanged at EOT (Table). Loss-of-function mutations in PTEN, a known PI3K inhibitor resistance marker, increased from 9% at baseline to 14% at EOT in Cohort A and from 12% at baseline to 22% at EOT in Cohort B.

Conclusions: Between baseline and EOT, only small variations in gene alterations in PIK3CA-mutated HR+, HER2– ABC were observed in the post-CDK4/6i setting. As the disease progressed, increases in loss-of-function mutations in PTEN at EOT in both Cohorts A and B suggested loss of PTEN in PI3K pathway may drive resistance to ALP. Early intervention with ALP, when the tumor is particularly driven by PIK3CA oncogenic mutations and before it develops more genomic complexity, may potentially provide better clinical outcomes.

Table. Gene Alteration Gain/Loss at Baseline/EOT Across Cohorts A and B

Citation Format: Dejan Juric, Nicholas Turner, Sherene Loi, Fabrice Andre, Stephen K. Chia, Komal Jhaveri, Patrick Neven, Rebecca Dent, Eva Ciruelos, Mukta Joshi, Estelle Roux, Heather Patino, Murat Akdere, Hope Rugo. Baseline and End-of-Treatment Biomarkers in Patients With PIK3CA-Mutated, Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer From BYLieve Study Cohorts A and B [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-09-12.

Alpelisib (ALP) + endocrine therapy (ET) in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–), PIK3CA-mutated (mut) advanced breast cancer (ABC): Baseline biomarker analysis and progression-free survival (PFS) by duration of prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) therapy in the BYLieve study

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Background: ALP (PI3K-α selective inhibitor and degrader) + fulvestrant (FUL) is approved for pts with HR+, HER2– ABC and a tumor mutation in PIK3CA (̃ 40% of these pts). Primary analyses from the Phase 2 BYLieve study demonstrated efficacy and safety of ALP + ET in pts with PIK3CA-mut, HR+, HER2– ABC in the post-CDK4/6i setting. Post hoc analyses, including pts with disease progression within 6 mo of CDK4/6i + ET treatment (Tx), confirmed ALP benefit regardless of duration of prior CDK4/6i. Here we assess baseline biomarkers in circulating tumor DNA (ctDNA) by duration of prior CDK4/6i Tx and PFS in pts from BYLieve Cohorts A and B. Methods: In the BYLieve study, pts with PIK3CA-mut, HR+, HER2– ABC had CDK4/6i + aromatase inhibitor (Cohort A) or + FUL (Cohort B) as immediate prior Tx to receiving ALP + FUL and ALP + letrozole (LET), respectively. At data cutoff dates, pts had ≥ 18-mo follow-up in Cohort A and ≥ 6-mo in Cohort B. In each cohort, pts were grouped based on duration of prior CDK4/6i Tx (≤ 6 mo or >6 mo). Alterations were detected on ctDNA using next-generation sequencing (PanCancer V2 Panel). PFS was assessed in each cohort and by duration of prior CDK4/6i Tx. Results: Of 127 and 126 pts enrolled in Cohorts A and B, respectively, 98 (≤ 6-mo: 24; >6-mo: 74) and 94 (≤ 6-mo: 28; >6-mo: 66) were included in this analysis based on availability of ctDNA samples, data on duration of prior CDK4/6i, and centrally confirmed PIK3CA-mut disease. In this population, median (m) PFS (95% CI) was 8.2 mo (5.6 - 9.5) and 5.6 mo (3.7 - 7.1) in Cohorts A and B, respectively. In Cohort A, mPFS (95% CI) was 12.0 mo (5.5-non estimable) and 6.2 mo (5.4 - 8.5) in the ≤ 6-mo and >6-mo groups, respectively. The OncoPrint genomic profiles showed that pts in the ≤ 6-mo vs >6-mo group had a lower median ctDNA fraction and fewer detected gene alterations, including in genes associated with ET and/or CDK4/6i resistance, and fewer chromosomes 8/11 amplifications (linked to early relapse). In Cohort B, mPFS was 5.9 mo (3.5 - 11.0) and 5.6 mo (3.7 - 7.1) in the ≤ 6-mo and >6-mo groups, respectively. Both groups had high median ctDNA fractions and complex tumor mutation profiles reflecting more extensive treatment history. Conclusions: Lower median ctDNA fraction and lower mutational complexity observed in Cohort A ≤ 6-mo vs >6-mo group was associated with numerically longer mPFS, potentially indicating increased dependence on the mutant PI3K-α. In Cohort B, both ≤ 6-mo and >6-mo groups had high median ctDNA fractions and similar tumor mutation profiles. Additional ctDNA and tissue analyses are needed to elucidate the correlation between ALP + ET efficacy and treatment timing and baseline genomic complexity.

Abstract P5-13-03: Alpelisib + endocrine therapy (ET) in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), PIK3CA-mutated advanced breast cancer (ABC) previously treated with cyclin-dependent kinase 4/6 inhibitor (CDK4/6i): Biomarker analyses from the Phase II BYLieve study

Introduction: Alpelisib (ALP, a PI3Kα inhibitor and degrader) + ET has demonstrated efficacy in patients (pts) with HR+, HER2-, PIK3CA-mutated ABC progressing on/after CDK4/6i + ET in the ongoing Phase II BYLieve study (NCT03056755). The primary endpoint, in pts with centrally confirmed PIK3CA mutation in tumor tissue (modified full analysis set [mFAS]), was met in Cohorts A (ALP + fulvestrant [FUL]) and B (ALP + letrozole [LET]) with 50.4% (95% CI, 41.2%-59.6%) of 121 pts and 46.1% (36.8%-55.6%) of 115 pts alive and without disease progression at 6 mo, respectively. Activating PIK3CA mutations, occurring in ~40% of tumors, confer worse prognosis in the advanced setting. Here, we assess the correlation between progression-free survival (PFS) and other baseline biomarkers among pts in BYLieve Cohorts A and B. Methods: Enrolled pre-/postmenopausal women with HR+, HER2-, PIK3CA-mutated ABC received CDK4/6i + aromatase inhibitor (Cohort A) or FUL (Cohort B), as immediate prior treatment (Tx). Pts received ALP 300 mg PO QD + FUL 500 mg IM Q28D and C1D15 (Cohort A) or ALP 300 mg PO QD + LET 2.5 mg PO QD (Cohort B) as study Tx. This exploratory analysis of baseline biomarkers identified gene alterations using an error-connected sequencing ctDNA assay (Novartis PanCancer gene-panel) in plasma samples from pts with a centrally confirmed PIK3CA mutation in tumor tissue from Cohorts A and B. PFS was estimated using the Kaplan-Meier method in subgroups of pts based on high (≥10%) or low (<10%) ctDNA fraction, high (≥10) or low (<10) tumor mutation burden (TMB), and amplification (amp) status of chromosomes (chr) 8 or 11 amplicons (frequently observed in breast cancer and usually associated with early relapse). Results: In Cohorts A and B, 102 of 127 enrolled pts and 97 of the 126 enrolled pts were included in this analysis, respectively. In this analysis, median PFS (mPFS) was 7.3 mo in Cohort A and 5.7 mo in Cohort B, consistent with observations in the mFAS (Table 1). Pts with a low ctDNA fraction or TMB at baseline had longer mPFS than pts with high ctDNA fraction or TMB (Table 1). In addition to PIK3CA alterations observed in 73% of tumors from pts in Cohorts A and B, the most frequently altered genes in the studied population were ESR1 (27% and 28%) and TP53 (25% and 26%) in Cohorts A and B, respectively. Across both cohorts, pts whose tumors had loss of function alterations in genes known to mediate resistance to CDK4/6i (PTEN, RB1, CHD4, FAT1, NF1, ATM, CDKN2A-C) derived clinical benefit (partial response or stable disease) from ALP + ET. Amp of known amplicons on chr 8 (eg, FGFR1, TACC1) or 11 (eg, CCND1, FGF3, FGF4) were observed in 5%-8% of pts in Cohort A and 8%-11% of pts in Cohort B. Pts whose tumors had no gene amp on chr 8 and/or 11 had longer mPFS than pts whose tumors had an amp (Table 1). Similar results were observed when analyzing chr 8 (6.33 mo vs 4.92 mo) and chr 11 (6.33 mo vs 4.63 mo) separately in pts from Cohorts A plus B. Conclusion: In pts with HR+, HER2-, PIK3CA-mutated ABC, ALP was effective in the post-CDK4/6i setting regardless of ET partner and tumor genomic profile (including in presence of alterations in genes associated with CDK4/6i resistance). The absence of cross-resistance may allow pts with PIK3CA-mutated disease to benefit from ALP after disease progression on/after CDK4/6i.

Table 1.mPFS in pts from BYLieve Cohorts A and B based on baseline biomarker statusCohort A (ALP + FUL)Cohort B (ALP + LET)nmPFS, mo (95% CI) nmPFS, mo (95% CI)Overall (mFASa)1,21217.3 (5.6-8.3)1155.7 (4.5-7.2)Patients with available plasma sample for the biomarker analysisb1027.37 (5.60-8.67)975.70 (3.77-7.33)ctDNA fractionHigh (≥10%)655.60 (4.00-7.37)685.43 (3.70-7.20)Low (<10%)37NE297.33 (5.83-11.00)TMBHigh (≥10)103.85 (0.47-8.33)154.60 (1.67-5.73)Low (<10)716.13 (5.43-9.60)645.63 (3.73-7.50)Chr 8 or 11 amplificationWith174.23 (1.70-6.13)213.77 (1.93-7.37)Without858.40 (5.70-9.60)766.00 (5.20-7.53)Chr, chromosome; ctDNA, circulating tumor DNA; NE, not estimable; mPFS, median progression-free survival; TMB, tumor mutation burden. aPatients who received at least 1 dose of study treatment and had centrally confirmed PIK3CA mutation by a Novartis-designated laboratory were included in the mFAS. bOnly includes patients with centrally confirmed PIK3CA mutation in tumor tissue. 1. Rugo HS, et al. Lancet Oncol. 2021;22(4):489-498; 2. Rugo HS, et al. SABCS 2020. Poster PD2-07.

Citation Format: Dejan Juric, Nicholas Turner, Aleix Prat, Stephen Chia, Eva M Ciruelos, Manuel Ruiz-Borrego, Pamela Drullinsky, Florence Lerebours, Thomas Bachelot, O. Alejandro Balbin, Mukta Joshi, Estelle Roux, Christina H Arce, Murat Akdere, Hope S Rugo. Alpelisib + endocrine therapy (ET) in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), PIK3CA-mutated advanced breast cancer (ABC) previously treated with cyclin-dependent kinase 4/6 inhibitor (CDK4/6i): Biomarker analyses from the Phase II BYLieve study [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-03.

Abstract PD15-01: Impact of ESR1 mutations on endocrine therapy (ET) plus alpelisib benefit in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), PIK3CA-mutated, advanced breast cancer (ABC) who progressed on or after prior cyclin-dependent kinase inhibitor (CDK4/6i) therapy in the BYLieve trial

Introduction: Endocrine-based therapy is the standard of care for patients (pts) with HR+ ABC. Acquired ESR1 mutations (mut) have been reported in up to 56% of pts with HR+ ABC progressing after prior treatment with ET, and aromatase inhibitors (AIs) in particular. Alpelisib (ALP) is an α-selective PI3K inhibitor and degrader approved in combination with fulvestrant (FUL) for the treatment of HR+, HER2-, PIK3CA-mut ABC. The primary analysis of Cohorts A and B of the Phase II BYLieve trial demonstrated the safety and efficacy of ALP + ET in the post-CDK4/6i setting. We assessed the association between progression-free survival (PFS) and baseline ESR1 mut among pts in Cohorts A and B of the BYLieve trial. Methods: Cohorts A and B of the BYLieve trial included pre-/postmenopausal women with HR+, HER2-, PIK3CA-mut ABC who received CDK4/6i + AI (Cohort A) or CDK4/6i + FUL (Cohort B) as immediate prior therapy. Pts in Cohort B may have also received prior AI therapy. Pts received ALP 300 mg PO QD + FUL 500 mg IM Q28D and C1D15 (Cohort A) or ALP 300 mg PO QD + LET 2.5 mg PO QD (Cohort B). ESR1 mut was analyzed as an exploratory endpoint, using an error-corrected sequencing ctDNA assay (Novartis PanCancer gene-panel), in baseline plasma samples from pts with centrally confirmed PIK3CA mut in tumor tissue from Cohorts A and B. PFS by mut status was estimated using the Kaplan-Meier method. P values provided are nominal. No multiplicity adjustments were made, therefore, statistical interpretation should be made with caution. Results: 127 pts with ≥6 mo follow-up (median follow-up: 11.7 mo) were enrolled in Cohort A as of the 17 December 2019 data cut-off and 126 pts with ≥6 mo follow-up (median follow-up: 15.0 mo) were enrolled in Cohort B as of the 14 August 2020 data cut-off. 103 (81.7%) pts in Cohort B progressed on prior AI therapy (adjuvant/metastatic setting). 102 pts from Cohort A and 97 pts from Cohort B had available plasma samples and were included in this analysis. Similar outcomes were observed in this analysis and in the overall population (Table 1). At baseline, 26% (27/102) of pts in Cohort A and 26% (25/97) of pts in Cohort B had ESR1 mut detected. In Cohort A (ALP + FUL), a numerically lower PFS was observed in pts with ESR1-mut disease, but the wide confidence interval (CI) suggests no difference in risk of progression between those with and without ESR1 mut. In Cohort B (ALP + LET), pts with ESR1-mut disease had a shorter PFS compared with those without ESR1-mut disease. A possible limitation is that baseline characteristics of these subgroups may not be balanced.

Conclusion: Similar proportion of pts had ESR1-mut disease at baseline in both cohorts. All pts in Cohort A progressed on prior CDK4/6i + AI and most pts enrolled in Cohort B also progressed on prior AI therapy. This analysis suggests that pts with ESR1 mut tend to have lower PFS than those without a mut, and that ALP + LET might be less effective in pts with ESR1 mut. This adds to prior data that ESR1 mut reduce the efficacy of AI-based combination therapy. In pts with ESR1 mut detected after prior CDK4/6i therapy, ALP + FUL (the approved combination for PIK3CA-mut ABC) warrants consideration as an alternative treatment option. Studies of ALP in combination with new oral, selective estrogen-receptor degraders are also ongoing.

Table 1.Median PFS in BYLieve Cohorts A and B.Cohort A (ALP + FUL)Cohort B (ALP + LET)Overall (mFASa), N1,2121115mPFS, months (95% CI)7.3 (5.6-8.3)5.7 (4.5, 7.2)Patients with available plasma samples for ESR1-mutation testing,b N10297mPFS, months (95% CI)7.37 (5.60-8.67)5.70 (3.77-7.33)With ESR1 mutation (n=27)With ESR1 mutation (n=25) Without ESR1 mutation (n=72)mPFS, months (95% CI)5.55 (3.75-8.54)8.28 (5.45-9.46)4.57 (3.06-5.65)7.03 (4.50-8.31)Hazard ratio (95% CI)0.76 (0.44-1.33)0.55 (0.32-0.92)P value (nominal)0.30.02ALP, alpelisib; FUL, fulvestrant; LET, letrozole; mFAS, modified full analysis set; mPFS, median progression-free survival. . aPatients who received at least 1 dose of study treatment and had centrally confirmed PIK3CA mutation by a Novartis-designated laboratory were included in the mFAS. bOnly includes patients with centrally confirmed PIK3CA mutation in tumor tissue.1. Rugo HS, et al. Lancet Oncol. 2021;22(4):489-498; 2. Rugo HS, et al. SABCS 2020. Poster PD2-07.

Citation Format: Nick Turner, Hope S Rugo, Eva M Ciruelos, Manuel Ruiz-Borrego, Pamela Drullinsky, Florence Lerebours, Aleix Prat, Thomas Bachelot, Stephen Chia, Alejandro Balbin, Mukta Joshi, Estelle Roux, Christina H Arce, Murat Akdere, Dejan Juric. Impact of ESR1 mutations on endocrine therapy (ET) plus alpelisib benefit in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), PIK3CA-mutated, advanced breast cancer (ABC) who progressed on or after prior cyclin-dependent kinase inhibitor (CDK4/6i) therapy in the BYLieve trial [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD15-01.

Abstract PD13-05: Alpelisib + fulvestrant in patients with PIK3CA-mutated, HR+, HER2— advanced breast cancer (ABC) who received chemotherapy or endocrine therapy (ET) as immediate prior treatment: BYLieve Cohort C primary results and exploratory biomarker analyses

Introduction: Alpelisib (ALP), an inhibitor and degrader of phosphatidylinositol-3-kinase α (PI3Kα), + fulvestrant (FUL) demonstrated efficacy in PIK3CA-mutated, HR+, HER2- ABC in the phase 3 SOLAR-1 trial, which included only 20 patients (pts) with prior CDK4/6 inhibitor (CDKi) in the PIK3CA-mutated cohort. BYLieve (NCT03056755), a phase 2, open-label, 3-cohort noncomparative study, evaluates ALP + endocrine therapy (ET; FUL or letrozole [LET]) in pts with PIK3CA-mutated, HR+, HER2- ABC, progressing on/after prior therapies, including CDKi + ET. Cohorts A and B were restricted to pts receiving CDKi + (aromatase inhibitor [AI] or FUL), respectively, as immediate prior therapy, but Cohort C included pts whose cancer progressed on/after AI (in adjuvant or metastatic setting), and who received chemotherapy (CT; any line), or ET (FUL or LET monotherapy or with targeted therapy, including CDKi + FUL, but not CDKi + AI) as immediate prior treatment. Cohorts A and B demonstrated efficacy and safety of ALP + ET after prior CDKi. Here, we report primary results and biomarker analyses from Cohort C.. Methods: Pts in Cohort C received ALP 300 mg orally QD + FUL 500 mg intramuscular Q28D + C1D15. The primary endpoint was assessed in each cohort separately and is the proportion of pts with centrally confirmed PIK3CA mutation alive and without disease progression at 6 mo per local assessment; 95% CIs are calculated using Clopper and Pearson (1934) exact method. The 95% CI lower bound of the primary endpoint >30% is clinically meaningful evidence of treatment effect. In an exploratory analysis of baseline biomarkers using ctDNA, progression-free survival (PFS) was estimated in pt subgroups per high (≥10%) or low (<10%) ctDNA fraction and ESR1 mutational status via Kaplan-Meier estimation.. Results: 127 pts were enrolled in Cohort C (1 pt discontinued prior to treatment start) with ≥6 mo follow-up by the cutoff date (14 Jun 2021); 115 had a centrally confirmed PIK3CA mutation. Median follow-up was 11.4 mo (range, 0-23 mo); 79 (62.7%) pts had ≥2 prior lines of therapy in the metastatic setting, 58 (46.0%) pts had prior CT exposure in the metastatic setting, and 41 (32.5%) pts had prior FUL exposure in the metastatic setting. The primary endpoint was met, with 48.7% (95% CI, 39.3%-58.2%) of pts alive and without disease progression at 6 mo. Median PFS (mPFS) was 5.6 mo (95% CI, 5.4-8.1 mo). The most common all-grade adverse events (AEs) by preferred term were hyperglycemia (n=82, 65.1%), diarrhea (n=66, 52.4%), nausea (n=51, 40.5%), and rash (n=49, 38.9%). Grade ≥3 AEs (≥10%) included hyperglycemia (n=30, 23.8%) and rash (n=17, 13.5%). AEs leading to discontinuation occurred in 15.1% (n=19) of pts; most frequent AEs leading to discontinuation were rash (n=5, 4.0%) and hyperglycemia (n=4, 3.2%). Exploratory biomarker analyses in 74 pts who had available baseline biomarker samples at data cutoff showed that pts with a low ctDNA fraction (n=23) had longer mPFS than pts with high ctDNA fraction (n=51; 16.7 [95% CI, 10.4-19.5] vs 5.4 [95% CI, 2.9-7.2] mo; p<0.001, HR=0.31 [95% CI, 0.2-0.6]). Efficacy was similar in pts with (n=20) and without (n=54) ESR1-mutated tumors (6.3 [95% CI, 2.8-8.3] vs 8.3 [95% CI, 5.5-16.7] mo; p=0.095, HR=0.59 [95% CI, 0.3-1.1]).. Conclusion: In Cohort A of BYLieve, efficacy of ALP + FUL suggests clinical benefit immediately after CDKi + AI; Cohort C confirms clinically relevant activity of ALP + FUL in a heterogeneous population, primarily treated in the third line or later, and potentially regardless of ESR1 status or ctDNA fraction, with no new safety signals detected. Together, these data confirm that ALP targets the effects of the PIK3CA-driver oncogene in HR+, HER2- ABC.

Citation Format: Hope S Rugo, Patrick Neven, Isabel Saffie, Yeon Hee Park, Michelino De Laurentiis, Florence Lerebours, Eva Maria Ciruelos, Nicholas Turner, Dejan Juric, Ennan Gu, Christina H Arce, Mukta Joshi, Estelle Roux, Murat Akdere, Stephen Chia. Alpelisib + fulvestrant in patients with PIK3CA-mutated, HR+, HER2— advanced breast cancer (ABC) who received chemotherapy or endocrine therapy (ET) as immediate prior treatment: BYLieve Cohort C primary results and exploratory biomarker analyses [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD13-05.

Confirmation of the systematic presence of tin particles in fallopian tubes or uterine horns of Essure implant explanted patients: A study of 18 cases with the same pathological process

OBJECTIVE

To examine associations between local and systemic symptoms and the wear of the tin weld of Essure implants.

DESIGN

study of a series of cases.

SETTINGS

Two French hospitals.

PARTICIPANTS

Eighteen patients explanted by hysterectomy and salpingectomy for removal of their Essure implants between September 2019 and July 2020, have had a common anatomopathological process.

MAIN OUTCOME MEASURES

anatomopathological examination by optical microscopy and mineralogical analysis of the fallopian tube or uterine horn with scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX). Evaluation of local and systemic symptoms with a questionnaire. Examination of blood metal assays (nickel, chromium, and tin).

RESULTS

anatomopathological examination highlights foreign body granulomas, fibrosis, adenomyosis, nonspecific inflammation, cysts and myomas in the Fallopian tubes, uterine horns, or both and mentions the presence of foreign bodies in seven cases. SEM-EDX analyses showed, systematically, the presence of tin particles integrated in the wall near the weld, generally in clusters, and with a size ranging from about one micron to several dozen microns. The questionnaire shows that the most frequent local symptoms were pelvic pain, urinary disorders, bleeding, and pains during intercourse. The most common systemic symptoms were: asthenia, visual disturbances, amnesia, giddiness, dorsal pains, headaches, and joint pains. The majority of local and systemic symptoms decreased after explantation, but sometimes incompletely. Before explantation, high levels of nickel, tin and chromium were observed in 11/17, 1/7 and 2/17 patients. After explantation, tin levels were high in 3/11 patients.

CONCLUSIONS

our new anatomopathological process systematically demonstrates the presence of tin particles in tissue near the weld. These particles could be responsible for granulomatous inflammations as well as local symptoms. Many of the systemic symptoms are consistent with chronic organotin poisoning but further studies are needed to find out whether tin from the solder can be converted to organotin in the patients' bodies.

Accuracy of peak mitral e-wave velocity in the diagnosis of heart failure with preserved ejection fraction in older patients with acute dyspnea

BACKGROUND

The diagnosis of heart failure with preserved ejection fraction is characterized by its complexity, especially for physicians without great experience in comprehensive transthoracic Doppler echocardiography. Peak mitral E-wave (E) velocity has been successfully correlated to invasive left ventricular diastolic pressures in patients with structural heart disease. The aim of the study was to address the accuracy of E in the diagnosis of heart failure with preserved ejection fraction in elderly patients with acute dyspnea.

METHODS

This prospective study included 29 consecutive patients ≥70 years of age with heart failure with preserved ejection fraction and acute dyspnea and 29 controls ≥70 years of age. The final diagnosis was supported by the 2016 ASE/EACVI recommendations.

RESULTS

Mean age of the overall population was 85±7 years. E was strongly correlated with left atrial volume index (r=0.72, P<0.001) and with peak velocity of tricuspid regurgitation (r=0.77, P<0.001). E >85cm/s was 90% sensitive and 93% specific in the diagnosis of heart failure with preserved ejection fraction (AUC, 0.95). E/e' (0.95) and E/(e'xs') (0.92) did not perform better.

CONCLUSION

E/e' and E/(e'xs') provide essential diagnostic and prognostic information in heart failure with preserved ejection fraction and deserve to be included in every report of comprehensive transthoracic Doppler echocardiography. E velocity is a very simple and user-friendly parameter that can be used for the sole diagnostic purpose in elderly patients with acute dyspnea by operators without great deal of experience, such as cardiologists without formal training, emergency physicians, intensive care anesthetists, internists and geriatricians.

Clinical relevance of spectral tissue Doppler-derived E/e' in older patients with preserved ejection fraction

BACKGROUND

The E/e' index measured in spectral tissue Doppler is included in the recommendations for the diagnosis by transthoracic Doppler echocardiography of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction. While E/e' is influenced by age in healthy individuals, no studies have evaluated this index in elderly patients. This study addressed the clinical relevance of E/e' in assessment of left ventricular diastolic function in elderly patients with preserved ejection fraction and its relevance from both a diagnostic and prognostic perspective based on the existing literature.

METHODS

A total of 76 patients≥70years of age were prospectively included. The analysis of left ventricular diastolic function was adapted from the 2016 ASE/EACVI recommendations without consideration of E/e'.

RESULTS

The mean age was 85years. In all, 42 patients had moderate-to-severe diastolic dysfunction (elevated left atrial pressure). Mean E/e' was significantly correlated with diastolic function (r=0.58, P<0.001). Mean E/e'>13.3 had a sensitivity of 86% and a specificity of 91% in the diagnosis of moderate-to-severe diastolic dysfunction (AUC: 0.92). E/(e'xs') (AUC: 0.89) and NT pro-BNP (AUC: 0.80) did not perform better than E/e'. The existing literature offers large body of evidence that E/e' provides essential diagnostic and prognostic information in older patients with cardiovascular disease.

CONCLUSION

E/e' is accurate in the diagnosis of significant diastolic dysfunction, in the diagnosis of heart failure with preserved ejection fraction and in risk stratification in older patients with cardiovascular disease.

[Does hypoalbuminemia contribute to the worsening of heart failure?]

BACKGROUND

Hypoalbuminemia has now emerged as a powerful prognosticator in heart failure regardless of age, clinical presentation, left ventricular ejection fraction and usual prognostic markers. Growing evidence is that this prognostic value persists after adjusting for causative factors for hypoalbuminemia such as malnutrition, inflammation and liver dysfunction.

OBJECTIVE

To address the prognostic relevance of hypoalbuminemia in frail elderly patients with well-characterized cardiogenic pulmonary edema at high risk for adverse outcome, beyond causative factors for low serum albumin levels. Serum albumin was measured after clinical stabilization to avoid hypervolemia.

RESULTS

In all, 67 patients with a mean age of 86 years were included. Hospital mortality was 30%. Patients who died and who survived were similar in age, ejection fraction, BNP concentration, serum creatinine, serum hemoglobin, total bilirubin and prealbumin. Patients who died had lower serum albumin levels (P<0.001), higher blood urea nitrogen (P=0.03) and higher C-reactive protein (P=0.02). In multivariate analysis, serum albumin was the sole independent predictor of hospital death (P<0.01), after adjusting for malnutrition (prealbumin P=ns), inflammation (C-reactive protein P=ns) and liver dysfunction (total bilirubin P=ns).

CONCLUSION

Serum albumin is a powerful prognosticator in frail elderly patients with acute cardiogenic pulmonary edema even after adjusting for main causative factors. These results suggest that hypoalbuminemia may contribute to the worsening of heart failure given the physiological properties of serum albumin that includes antioxidant activity and plasma colloid osmotic pressure action. Further studies are critically needed to address the relevance of prevention and correction of hypoalbuminemia in heart failure.

Lack of Association Between Antiphospholipid Antibodies and Migraine

We prospectively studied the prevalence of lupus anticoagulant, anticardiolipin antibodies (aCL) and various haemostatic parameters in 71 patients with migraine and compared the results with a control group of 32 subjects with back pain never having experienced migraine. The patients with migraine were divided into two groups: group I with migraine without (n = 18) and with aura lasting less than 60 min (n = 24) and group II with migraine with prolonged aura or migrainous infarction (complicated migraine, n = 29). The following results were obtained: a) no difference in aCL positivity was noted between migrainous patients and controls and between common migraine and complicated migraine patients and b) no statistically significant difference in haemostatic parameters (except for thrombin-antithrombin III complexes) was found between the two groups of migraine and between aCL positive and negative migrainous patients. These data suggest that anticardiolipin antibodies are not involved in the pathogenesis of migraine complications.

Understanding urban water performance at the city-region scale using an urban water metabolism evaluation framework

Water sensitive interventions are being promoted to reduce the adverse impacts of urban development on natural water cycles. However it is currently difficult to know the best strategy for their implementation because current and desired urban water performance is not well quantified. This is particularly at the city-region scale, which is important for strategic urban planning. This work aimed to fill this gap by quantifying the water performance of urban systems within city-regions using 'urban water metabolism' evaluation, to inform decisions about water sensitive interventions. To do this we adapted an existing evaluation framework with new methods. In particular, we used land use data for defining system boundaries, and for estimating natural hydrological flows. The criteria for gauging the water performance were water efficiency (in terms of water extracted externally) and hydrological performance (how much natural hydrological flows have changed relative to a nominated pre-urbanised state). We compared these performance criteria for urban systems within three Australian city-regions (South East Queensland, Melbourne and Perth metropolitan areas), under current conditions, and after implementation of example water sensitive interventions (demand management, rainwater/stormwater harvesting, wastewater recycling and increasing perviousness). The respective water efficiencies were found to be 79, 90 and 133 kL/capita/yr. In relation to hydrological performance, stormwater runoff relative to pre-urbanised flows was of most note, estimated to be 2-, 6- and 3- fold, respectively. The estimated performance benefits from water sensitive interventions suggested different priorities for each region, and that combined implementation of a range of interventions may be necessary to make substantive gains in performance. We concluded that the framework is suited to initial screening of the type and scale of water sensitive interventions needed to achieve desired water performance objectives.

[Usefulness of spectral tissue Doppler (E/e' ratio) in the management of patients with atrial fibrillation]

Atrial fibrillation is the most common cardiac rhythm disorder encountered in daily clinical practice. It carries high morbidity and mortality rates, mainly related to sudden death, heart failure and stroke. Validation of noninvasive markers in the diagnosis of heart failure with preserved ejection fraction and risk stratification is therefore attractive in this clinical setting. The spectral tissue Doppler-derived E/e' ratio is a simple and user-friendly index which has been validated in the assessment of left ventricular diastolic pressures, regardless of rhythm. A septal E/e' >11 is associated with invasive left ventricular diastolic pressures >15mmHg in patients with atrial fibrillation. Several studies have reported the clinical relevance of abnormal values of E/e' at rest and during exercise in the diagnosis and risk stratification of heart failure with preserved ejection fraction in patients with atrial fibrillation. There is now convincing evidence that increased E/e' is associated with adverse outcome in patients with atrial fibrillation and predicts the recurrence of arrhythmia after cardioversion or catheter ablation. In conclusion, we recommend the measurement of E/e' in each patient with atrial fibrillation referred for clinically indicated transthoracic Doppler echocardiography.

[Usefulness of natriuretic peptide testing and Doppler echocardiography at bedside in the diagnosis of acute heart failure]

Acute heart failure is a common condition that leads to hospital admission, with important mortality and readmission rates. A prompt and accurate diagnosis of this condition by hospitalists is essential for an early and tailored medical management. The use of natriuretic peptide testing (BNP and NT-proBNP) through a two cut-point strategy is currently recommended as the first-line diagnostic complement to the initial clinical evaluation in the acute care setting. Transthoracic Doppler echocardiography is an other noninvasive method that can be used at bedside, especially in patients with intermediate, inconclusive natriuretic peptides levels. In this regard, left ventricular ejection fraction and several simple Doppler indexes (restrictive mitral filling pattern, spectral tissue Doppler E/e' ratio), have been validated in the emergency diagnosis of acute heart failure. The aim of the present review is to overview the respective contribution of natriuretic peptides and Doppler echocardiography at bedside to the diagnosis of acute heart failure in the acute care setting.

Polishing surgical metal pieces, granulomatosis and mineralogical analysis

This report describes the case of a 44-year-old man with pulmonary nodules whose histological analysis initially suggested tuberculosis. The Mycobacterium tuberculosis (MT) culture was negative and a questionnaire revealed a professional activity of brushing and polishing surgical instruments without any protection for 7 years.  A mineralogical analysis by optical and electron microscopy was performed on both a healthy lung tissue biopsy and a lung nodule in a paraffin block. Electron microscopy analysis revealed the presence of metal particles (iron oxide, titanium oxide, aluminum oxide and steel) in both samples. This study suggests that mineralogical analysis combined with a questionnaire on dust exposure could help redirect the diagnosis of a dust-related disease.

The chloroplast genome of Euglena gracilis: the mosaic structure of a DNA segment linking the extra 16S rRNA gene with the rrn operon A

We have completed the analysis of a DNA segment of the chloroplast genome of Euglena gracilis Klebs, Z-strain, which links the 3' end of the extra 16S rRNA gene with the 5' end of the 16S rRNA gene of the rrn operon A. This region is a mosaic of several structural elements and contains an intact rrn interoperon spacer of 1,080 bp, an extra 5S rRNA gene, an open reading frame for 406 codons (ORF 406) which is flanked by short inverted repeats and a short direct repeat originating from the rrn interoperon spacer. It seems that a once complete rrn operon underwent in the past an insertion/deletion event leaving intact the 16S and 5S rRNA but totally excising the 16S-23S intergenic spacer and the 23S rRNA gene. Instead a protein coding gene of yet unknown function was inserted along with other structural elements.

Unravelling the relationships between Anopheles darlingi (Diptera: Culicidae) densities, environmental factors and malaria incidence: understanding the variable patterns of malarial transmission in French Guiana (South America)

Anopheles darlingi, one of the main malaria vectors in the Neotropics, is widely distributed in French Guiana, where malaria remains a major public-health problem. Elucidation of the relationships between the population dynamics of An. darlingi and local environmental factors would appear to be an essential factor in the epidemiology of human malaria in French Guiana and the design of effective vector-control strategies. In a recent investigation, longitudinal entomological surveys were carried out for 2-4 years in one village in each of three distinct endemic areas of French Guiana. Anopheles darlingi was always the anopheline mosquito that was most frequently caught on human bait, although its relative abundance (as a proportion of all the anophelines collected) and human biting rate (in bites/person-year) differed with the study site. Seasonality in the abundance of human-landing An. darlingi (with peaks at the end of the rainy season) was observed in only two of the three study sites. Just three An. darlingi were found positive for Plasmodium (either P. falciparum or P. vivax) circumsporozoite protein, giving entomological inoculation rates of 0·0-8·7 infectious bites/person-year. Curiously, no infected An. darlingi were collected in the village with the highest incidence of human malaria. Relationships between malaria incidence, An. darlingi densities, rainfall and water levels in the nearest rivers were found to be variable and apparently dependent on land-cover specificities that reflected the diversity and availability of habitats suitable for the development and reproduction of An. darlingi.

[Analysis of asbestos bodies and nude fibres in the lung parenchyma of operated lung cancers. A retrospective monocentric study of 73 cases]

We report on a study concerning a retrospective monocentric series of 73 lung cancers operated on between July 2004 and December 2009. All patients had a mineralogical analysis of a sample of lung tissue combined with an occupational questionnaire. This combination enables us to suggest a declaration of occupational exposure in almost one third of cases. We suggest that a healthy parenchymal fragment is to be obtained by biopsy routinely in cases of lung cancer surgery. The analysis should be carried out if the occupational survey does not demonstrate any evident exposure and if the patient is not known to be presenting a pleuropulmonary disease following asbestos exposure (pleural plaques and asbestosis).

[Comparative value of B-type natriuretic peptide and serum albumin concentration in the prediction of in-hospital mortality in elderly patients admitted for acute severe heart failure]

OBJECTIVE

To address the clinical relevance of serum albumin and B-type natriuretic peptide (BNP) concentration in the prediction of in-hospital death in elderly patients with acute severe heart failure.

PATIENTS AND METHODS

Seventy-four consecutive patients >70 years of age admitted for acute heart failure in NYHA class IV were prospectively included. BNP concentration was measured on admission and serum albumin concentration after clinical stabilization.

RESULTS

Mean age was 86.6+/-5.7 years. Sixty-five percent of patients had a normal left ventricular ejection fraction. Eighteen patients died during the in-hospital stay. Those patients who died were older, had higher blood urea nitrogen and BNP concentration, had lower systolic blood pressure and serum albumin concentration than patients who survived. Heart rate, rhythm, left ventricular ejection fraction, serum creatinine and hemoglobin did not differ according to outcome. By multivariate analysis, albumin (p=0.0017), BNP (p=0.016) and age (p=0.03) were independent predictors of in-hospital death. Serum troponin I measured on admission in 71 patients was predictive of in-hospital death (p=0.01), as well as serum total cholesterol measured after stabilization in 66 patients (p=0.004). However, these two variables no longer predicted outcome in multivariate models, unlike serum albumin and BNP.

CONCLUSION

Serum albumin and BNP offer independent, additional information for the prediction of in-hospital death in elderly patient with acute severe heart failure regardless of left ventricular ejection fraction.

Clustering follow-up time-series recorded by cardiac implantable devices

Follow-up of patients treated by cardiac resynchronization therapy (CRT) is of great interest to prevent health deterioration in the postoperative period. In this purpose, data recorded in implantable devices (ID) can be informative. They are large, multivariate, evolutive with time, and then difficult to interpret. This study proposes a methodology, based on Multiple Correspondence Analysis (MCA) and fuzzy coding, to i) reduce the dimensionality of these data, ii) characterize the factorial axes by the variables recorded in the ID, iii) identify evolutions of patients in the factorial plane which are related to health deterioration. The results show that the first three axes of the MCA contain more than 90% of the total variance and are linked to the functional state of the patients. A simple clustering of the patients is performed and defines an area of the factorial plane, correlated with a degradation of patients' clinical state.

[Usefulness of B-type natriuretic peptide (BNP) for the diagnosis of new-onset heart failure with a preserved left ventricular systolic function in longstanding hypertensive patients with acute dyspnea]

BACKGROUND

B-type natriuretic peptide (BNP) has been largely validated in the etiologic diagnosis of acute dyspnea. Nevertheless, its reliability in the setting of a preserved left ventricular systolic function (ejection fraction >50%) has not been adequately established.

OBJECTIVE

the study addressed the usefulness of BNP in the diagnosis of new-onset heart failure with a preserved systolic function in hypertensive patients hospitalized for acute dyspnea.

METHODS

59 consecutive hypertensive patients without history of heart failure and coronary disease were included. BNP was measured at presentation with the Triage system. Noninvasive estimation of left ventricular filling pressures by bedside tissue Doppler echocardiography at presentation was incorporated in the diagnostic criteria.

RESULTS

the 30 patients with heart failure were not significantly different from the 29 patients with noncardiac cause of acute dyspnea regarding age, gender, body mass index and ejection fraction. Median levels of BNP were significantly higher in heart failure (447 [245-644] versus 87 [43-139] pg/mL). By multivariate logistic regression analysis, BNP (odds ratio of 44, [3.6-531], p=0.003) provided independent and incremental diagnostic information over the clinical score of Boston criteria (2.25, [1.3-3.9], p=0.0037). A BNP value of >142 pg/mL (area under the ROC curve of 0.89, p<0.0001) was 93 sensitive and 79% specific for the diagnosis of heart failure in this setting.

CONCLUSION

BNP is a reliable biomarker of new-onset heart failure with a preserved systolic function in hypertensive patients, in particular older, hospitalized for acute dyspnea and can be safely integrated in the diagnostic strategy.

[Prognostic value of BNP for hospital mortality in elderly subjects hospitalised for acute diastolic cardiac failure]

The aim of this study was to evaluate the prognostic value of BNP in elderly patients hospitalised for acute diastolic cardiac failure. 108 consecutive subjects were included, aged at least 70 years old, hospitalised for isolated acute diastolic cardiac failure. All of them had a left ventricular ejection fraction > or = 50% and evidence of diastolic dysfunction on echocardiography performed shortly after admission. The plasma BNP concentration measured in the emergency department on admission was >100 pg/ml in all of the patients except five. It was positively correlated with age (R = 0.29, p = 0.002), with the plasma creatinine level (R = 0.37, p < 0.0001) and the plasma urea level (R = 0.41, p < 0.0001). On univariate analysis, compared to the patients who survived, the 20 patients who died before discharge were significantly older (88.6 versus 84.4 years, p = 0.01), and were more often residents of a care home (60 versus 31%. p = 0.02), had a lower systolic blood pressure on admission (127 +/- 33 versus 154 +/- 30 mm Hg), a higher plasma urea level (16.8 +/- 12 versus 8.9 +/- 5 mmol/l, p = 0.002) and a higher BNP (median = 1290 pg/ml, interquartile range: 721, 3026 pg/ml versus 430 pg/ml, interquartile range: 243, 886 pg/ml). On multivariate analysis, the only factors that remained significantly associated with mortality were the BNP levels (p = 0.005) and the systolic blood pressure (p = 0.01). The negative predictive value of a BNP level < 631 pg/ml (median) for death was 94% (95% confidence interval: 91 to 97%). We conclude that BNP does have an independent prognostic value for in-hospital death in elderly subjects with acute diastolic cardiac failure.

[Novel Doppler indexes of estimation of pulmonary capillary pressure: influence of age, feasibility in the acute setting and reproducibility]

BACKGROUND

The Doppler indexes E/Vp, E/Ea, 1000/(2 x IRT + Vp), 1000/(2 x IRT + Ea) and DTd (E: peak E mitral velocity; Vp: flow propagation velocity by color M-mode; Ea: peak early diastolic velocity at lateral mitral annulus by tissue Doppler; IRT: isovolumic relaxation time; DTd: deceleration time of the pulmonary venous diastolic wave) have been proposed for the non-invasive prediction of left ventricular filling pressures. However, the influence of age, the feasibility in acute setting and the reproducibility of these Doppler indexes have never been simultaneously investigated.

OBJECTIVE

The present study was conducted to evaluate the influence of age in 56 healthy subjects (57 +/- 20 years of age), the feasibility in 40 critically ill patients (72 +/- 13 years of age; 21 with decompensated heart failure) and the reproducibility in 15 patients.

RESULTS

Only the indexes E/Vp (R = 0.37, P = 0.005) and E/Ea (R = 0.72, P < 0.001) were correlated with age. The feasibility was 92, 90, 72, 72 and 45% for E/Ea, 1000/(2 x IRT + Ea), E/Vp, 1000/(2 x IRT +Vp) and DTd, respectively. The best reproducibility was observed for the Doppler parameters E and Ea.

CONCLUSION

Despite it is influenced by age, E/Ea appears to be the most useful index for predicting left ventricular filling pressures routinely.

[A new area for radiotherapy with favourable features]

Radiotherapy is a complex medical speciality involving technology research, biology research and clinical research. All these basic researches are performed in order to optimise the management of cancer treatment patients. The aim of the present review is to present radiotherapy as a moving speciality whatever the concerned section. It will be particularly described the new approaches in terms of technology but also clinical developments.

[Precipitating factors associated with diastolic heart failure in the elderly]

BACKGROUND

Beside basal myocardial dysfunction, acute heart failure involves associated factors, which increase pulmonary capillary pressure or decrease colloid osmotic pressure. The aim of this study was to evaluate the prevalence of these precipitating factors in a population presenting with acute heart failure with preserved left ventricular systolic function.

METHODS

Forty-eight patients (25 men, 78 +/- 10 years) presenting pulmonary edema with a left ventricular ejection fraction > 45% were included. All had a Doppler echocardiography at the time of intravenous loop diuretics initiation. Patients with severe valve disease or symptomatic coronary disease were excluded.

RESULTS

A history of heart failure, coronary disease, hypertension and diabetes was present in 62%, 42%, 64% and 33% of patients, respectively. On admission, mean left ventricular ejection fraction was 61 +/- 9% and 79% of patients had critical elevation in Doppler filling pressures. Associated factors were renal failure (creatinine clearance < 30 ml/min) in 33% patients, silent myocardial ischemia (troponin I > 0.5 ng/ml) in 31%, atrial fibrillation in 29%, high systolic blood pressure (> or = 160 mmHg) in 27%, major sepsis in 25%, severe hypoalbuminemia (< or = 2.5 g/dl) in 23%, and severe anemia (< 10 g/dl) in 17%, respectively. Four patients had no aggravating factor, whereas 34 and 10 patients had 1-2 and 3-4 associated factors, respectively.

CONCLUSION

Besides diastolic dysfunction, factors leading to a critical decrease in the oncotic pressure such as pulmonary capillary pressure gradient are found in most of the elderly patients presenting acute diastolic heart failure and must be checked systematically.

INK4a-ARF mutations in skin carcinomas from UV irradiated hairless mice

To characterize further the role of the INK4a-ARF locus in the multistep process of skin carcinogenesis, we performed a mutational analysis of this locus in skin lesions from hairless mice either irradiated with UVB alone or with a solar simulator delivering UVA + B. INK4a-ARF mutations were present in five of 57 squamous cell carcinomas (9%), but no mutation was detected in precancerous lesions. All mutations were C:G > T:A transitions located at dipyrimidic sites, the hallmark of UVB mutagenesis. Three mutations affected only the p19(ARF) reading frame, whereas two mutations affected only the p16(INK4a) transcript. This study demonstrates for the first time UV-induced mutations of INK4a-ARF that occur in a small percentage in late stages skin tumors.

[Silent ischemia and acute cardiac insufficiency with normal systolic function: diagnostic value of troponin I measurement]

The physiopathological mechanisms resulting in increased left ventricular pressures in acute cardiac failure with normal systolic function are not well understood. Although coronary artery disease is commonly associated with acute episodes, the diagnostic value of troponin I measurement and the prevalence of ischaemia as the predisposing factor are not known. Twenty coronary patients (mean age 77 +/- 9 years) in acute cardiac failure with left ventricular ejection fractions of 50% or over and without angina, were studied retrospectively. The diagnostic value of troponin I (cTnI, AxSYM, method) was assessed by comparing with a control group of 16 acute cardiac failure patients without coronary disease. The frequency of hypertension and diabetes in the coronary group was 50 and 45% respectively. At the time of investigation, the pulmonary capillary and systemic arterial pressures were comparable in the coronary patients irrespective of the cTnl value. At threshold levels of 0.5 microgram/l, cTnl had a specificity of 100% and confirmed ischaemia in 60% of the coronary patients. Ischaemia was the commonest predisposing factor for increased cardiac pressures. Over a 268 +/- 101 days follow-up period, half the coronary patients were readmitted for acute cardiac failure and a third of them died. The authors conclude that silent ischaemia is a common predisposing factor for acute cardiac failure in coronary patients with normal systolic function and troponin I measurement is a useful diagnostic help.

[Value of Doppler indices of diastolic left ventricular dysfunction in acute cardiac insufficiency]

OBJECTIVE

To examine the prevalence of diastolic dysfunction by Doppler study in acute cardiac failure.

CONTEXT

A recent study showed that diastolic dysfunction is constant in stable cardiac failure with preserved systolic function and suggested that its measurement was not necessary for the diagnosis of diastolic cardiac failure, but the prevalence of diastolic dysfunction in acute cardiac failure is not known.

METHOD

The mitral and pulmonary venous profiles, the propagation velocity Vp of colour filling flow, and the lateral velocity Ea of the mitral ring in DTI were studied at the time of treatment initiation in 28 patients in sinus rhythm and in acute cardiac failure (11 NYHA IV and 17 with pulmonary oedema), of whom 18 had an ejection fraction greater than 50%.

RESULTS

Diastolic dysfunction was present in the combined study of mitral and pulmonary profiles in 95% and 100% respectively of patients in cardiac failure with preserved systolic function and altered systolic function, and Vp < 45 and/or Ea < 8 cm/s was observed in 55% and 100% respectively of these patients. At respective pathological threshold values of 1.5 and 10, the combined indices E/Vp and E/Ea were concordant with the evaluation of filling pressures in 83% of patients with preserved systolic function and 100% of the systolic cardiac failure cases.

CONCLUSION

Diastolic dysfunction is almost constant in acute cardiac failure independently of the ejection fraction value. However, normal values of Ea and Vp do not exclude the diagnosis of diastolic cardiac insufficiency in the acute situation.

In vitro effect of air pollutants on human bronchi

A useful approach for constructing dose-response relationships and for studying the underlying mechanisms by which a xenobiotic agent enhances airway reactivity is to measure the response of an isolated airway following ex vivo exposure to a pollutant. We have in this way determined the dose-response relationship between ex vivo exposure to pollutants such as nitrogen dioxide (NO2), the aldehyde acrolein, and ozone (O3) and the reactivity to agonists in human isolated bronchial smooth muscle. We have also investigated the underlying alteration in the cellular mechanisms of airway smooth-muscle contraction induced by such exposure and found that it is related to alteration in calcium signaling at the site of the airway smooth-muscle cell. Finally, although there is epidemiological evidence that an increase in allergic diseases such as asthma may be linked to air pollution, there are few experimental data to address this issue. The final aim of this study was therefore to investigate the interaction between passive sensitization and exposure to pollutants in human isolated airways. We have examined (i) the effect of a pre-exposure to pollutants on the contraction of sensitized bronchi in response to a specific antigen and (ii) the effect of passive sensitization on the contraction in response to nonspecific agonists in bronchi pre-exposed to pollutants. The results indicate a combined effect of immunological sensitization and exposure to pollutants; that is, passive sensitization and exposure to pollutants act in a synergistic manner on human bronchial smooth-muscle reactivity in response to both specific antigens and nonspecific agonists.

[Origin and evolution of the respiratory tract in vertebrates]

The description of the evolution of Vertebrate lung is based on comparative anatomy and physiology, combined with phylogenetics. An air-breathing organ (ABO), in addition to gill respiration, appeared in fishes about 400 M years ago. It consisted of a single primitive lung ventilated by a buccal pump. This breathing system was adopted by the first terrestrial tetrapods, and is largely preserved in current amphibians. In the Amniotes, the buccal pulsing pump has been replaced with a costal aspiration pump. In mammals, this ABO evolved into a bronchoalveolar lung. In "Reptiles", the ABO is a partitioned lung with one or several cavities. It serves as a gas exchanger but also as an O(2) reserve, which allows for long periods of apnoea. In birds, the ABO is a tubular structure ventilated by unidirectional airflow. Such a breathing system allows for high rates of O(2) consumption. The diversity of structure and function of the Vertebrate lung should not be analysed as a progression of increasing complexity towards mammal lungs, but rather as diverse responses to varying environmental conditions and phylogenic constraints, and to the challenge of acquiring oxygen necessary for aerobic metabolism.

Evaluation of the global optimisation method within the upper limb kinematics analysis

The aim of this study is to assess the performances of the global optimisation (GO) method (Bone position estimation from skin marker co-ordinates using GO with joint constraints. Journal of Biomechanics 32, 129-134) within the upper limb kinematics analysis. First the model of the upper limb is presented. Then we apply GO method in order to reduce skin movement artefacts that imply relative movement between markers and bones. The performances of the method are then evaluated with the help of simulated movements of the upper limb. Results show a significant reduction of the errors and of the variability due to skin movement.

Modelling of Ca2+-activated chloride current in tracheal smooth muscle cells

Stimulation of airway myocytes by contractile agents such as acetylcholine (ACh) activates a Ca2+-activated Cl- current (I(ClCa)) which may play a key role in calcium homeostasis of airway myocytes and hence in airway reactivity. The aim of the present study was to model I(ClCa) in airway smooth muscle cells using a computerised model previously designed for simulation of cardiac myocyte functioning. Modelling was based on a simple resistor-battery permeation model combined with multiple binding site activation by calcium. In order to validate the model, a combination of equations, used to mimic [Ca2+]i response to ACh stimulation, were incorporated into the model. The results indicate that the model developed in this article accounts for experimental recordings and electrophysiological characteristics of this current in airway smooth muscle cells, with parameter values consistent with those calculated from experimental data. Such a model may thus be used to predict I(ClCa) functioning, though additional experimental data from airway myocytes would be useful to more accurately determine some parameter values of the model.