A multicentre validation of Metasin: a molecular assay for the intraoperative assessment of sentinel lymph nodes from breast cancer patients

Aims: Treatment strategies for breast cancer continue to evolve. No uniformity exists in the UK for the management of node‐positive breast cancer patients. Most centres continue to use conventional histopathology of sampled sentinel lymph nodes (SLNs), which requires delayed axillary clearance in up to 25% of patients. Some use touch imprint cytology or frozen section for intraoperative testing, although both have inherent sensitivity issues. An intraoperative molecular diagnostic approach helps to overcome some of these limitations. The aim of this study was to assess the clinical effectiveness of Metasin, a molecular method for the intraoperative evaluation of SLNs. Methods and results: RNA from 3296 lymph nodes from 1836 patients undergoing SLN assessment was analysed with Metasin. Alternate slices of tissue were examined in parallel by histology. Cases deemed to be discordant were analysed by protein gel electrophoresis. There was concordance between Metasin and histology in 94.1% of cases, with a sensitivity of 92% [95% confidence interval (CI) 88–94%] and a specificity of 97% (95% CI 95–97%). Positive and negative predictive values were 88% and 98%, respectively. Over half of the discordant cases (4.4%) were ascribed to tissue allocation bias (TAB). Conclusions: Clinical validation of the Metasin assay suggests that it is sufficiently sensitive and specific to make it fit for purpose in the intraoperative setting

Expression of Interest for a Phase-II LHCb Upgrade: Opportunities in flavour physics, and beyond, in the HL-LHC era

https://cds.cern.ch/record/224431

Branching Fraction Measurements of the Rare Bs0→ϕμ+μ−B^0_s\rightarrow\phi\mu^+\mu^- and Bs0→f2′(1525)μ+μ−B^0_s\rightarrow f_2^\prime(1525)\mu^+\mu^- Decays

The branching fraction of the rare $B^0_s\rightarrow\phi\mu^+\mu^-$ decay is measured using data collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to integrated luminosities of 1, 2, and 6 fb$^{-1}$, respectively. The branching fraction is reported in intervals of q$^2$, the square of the dimuon invariant mass. In the q$^2$ region between 1.1 and 6.0 GeV$^2$/c$^4$, the measurement is found to lie 3.6 standard deviations below a standard model prediction based on a combination of light cone sum rule and lattice QCD calculations. In addition, the first observation of the rare $B^0_s\rightarrow f_2^\prime(1525)\mu^+\mu^-$ decay is reported with a statistical significance of 9 standard deviations and its branching fraction is determined

Study of coherent J/ψJ/\psi production in lead-lead collisions at sNN \sqrt{{\mathrm{s}}_{\mathrm{NN}}} = 5 TeV

International audienceCoherent production of J/ψ mesons is studied in ultraperipheral lead-lead collisions at a nucleon-nucleon centre-of-mass energy of 5 TeV, using a data sample collected by the LHCb experiment corresponding to an integrated luminosity of about 10 μb$^{−1}$. The J/ψ mesons are reconstructed in the dimuon final state and are required to have transverse momentum below 1 GeV. The cross-section within the rapidity range of 2.0 < y < 4.5 is measured to be 4.45 ± 0.24 ± 0.18 ± 0.58 mb, where the first uncertainty is statistical, the second systematic and the third originates from the luminosity determination. The cross-section is also measured in J/ψ rapidity intervals. The results are compared to predictions from phenomenological models.[graphic not available: see fulltext

Searches for 25 rare and forbidden decays of D+D^{+} and Ds+ {D}_s^{+} mesons

International audienceA search is performed for rare and forbidden charm decays of the form ${D}_{(s)}^{+}\to {h}^{\pm }{\mathrm{\ell}}^{+}{\mathrm{\ell}}^{\left(\prime \right)\mp }$, where h$^{±}$ is a pion or kaon and ℓ$^{(′)±}$ is an electron or muon. The measurements are performed using proton-proton collision data, corresponding to an integrated luminosity of 1.6 fb$^{−1}$, collected by the LHCb experiment in 2016. No evidence is observed for the 25 decay modes that are investigated and 90 % confidence level limits on the branching fractions are set between 1.4 × 10$^{−8}$ and 6.4 × 10$^{−6}$. In most cases, these results represent an improvement on existing limits by one to two orders of magnitude.[graphic not available: see fulltext

Observation of New Resonances Decaying to J/ψK+J/\psi K^++ and J/ψϕJ/\psi \phi

International audienceThe first observation of exotic states with a new quark content cc¯us¯ decaying to the J/ψK+ final state is reported with high significance from an amplitude analysis of the B+→J/ψϕK+ decay. The analysis is carried out using proton-proton collision data corresponding to a total integrated luminosity of 9  fb-1 collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. The most significant state, Zcs(4000)+, has a mass of 4003±6-14+4  MeV, a width of 131±15±26  MeV, and spin parity JP=1+, where the quoted uncertainties are statistical and systematic, respectively. A new 1+  X(4685) state decaying to the J/ψϕ final state is also observed with high significance. In addition, the four previously reported J/ψϕ states are confirmed and two more exotic states, Zcs(4220)+ and X(4630), are observed with significance exceeding 5 standard deviations

Search for the doubly heavy baryons Ωbc0\Omega^0_{bc} and Ξbc0\Xi^0_{bc} decaying to Λc+π−\Lambda^+_c \pi^- and Ξc+π−\Xi^+_c \pi^-

The first search for the doubly heavy baryon and a search for the baryon are performed using collision data collected via the experiment from 2016 to 2018 at a centre-of-mass energy of , corresponding to an integrated luminosity of 5.2 . The baryons are reconstructed via their decays to and . No significant excess is found for invariant masses between 6700 and 7300 , in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 . Upper limits are set on the ratio of the and production cross-section times the branching fraction to ( ) relative to that of the ( ) baryon, for different lifetime hypotheses, at 95% confidence level. The upper limits range from to for the ( ) decay, and from to for the ( ) decay, depending on the considered mass and lifetime of the ( ) baryon

Search for the radiative Ξb−→Ξ−γ\Xi_b^-\to\Xi^-\gamma decay

International audienceThe first search for the rare radiative decay ${\Xi}_b^{-}$ → Ξ$^{−}$γ is performed using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb$^{−1}$. The ${\Xi}_b^{-}$ → Ξ$^{−}$J/ψ channel is used as normalization. No ${\Xi}_b^{-}$ → Ξ$^{−}$γ signal is found and an upper limit of $\mathcal{B}$(${\Xi}_b^{-}$ → Ξ$^{−}$γ) < 1.3 × 10$^{−4}$ at 95% confidence level is obtained.[graphic not available: see fulltext

Search for CP violation in D(s)+→h+π0 {D}_{(s)}^{+}\to {h}^{+}{\pi}^0 and D(s)+→h+η {D}_{(s)}^{+}\to {h}^{+}\eta decays

International audienceSearches for CP violation in the two-body decays ${D}_{(s)}^{+}\to {h}^{+}{\pi}^0$ and ${D}_{(s)}^{+}\to {h}^{+}\eta$ (where h$^{+}$ denotes a π$^{+}$ or K$^{+}$ meson) are performed using pp collision data collected by the LHCb experiment corresponding to either 9 fb$^{−1}$ or 6 fb$^{−1}$ of integrated luminosity. The π$^{0}$ and η mesons are reconstructed using the e$^{+}$e$^{−}$γ final state, which can proceed as three-body decays π$^{0}$→ e$^{+}$e$^{−}$γ and η → e$^{+}$e$^{−}$γ, or via the two-body decays π$^{0}$→ γγ and η → γγ followed by a photon conversion. The measurements are made relative to the control modes ${D}_{(s)}^{+}\to {K}_{\mathrm{S}}^0{h}^{+}$ to cancel the production and detection asymmetries. The CP asymmetries are measured to be${\displaystyle \begin{array}{c}{\mathcal{A}}_{CP}\left({D}^{+}\to {\pi}^{+}{\pi}^0\right)=\left(-1.3\pm 0.9\pm 0.6\right)\%,\\ {}{\mathcal{A}}_{CP}\left({D}^{+}\to {K}^{+}{\pi}^0\right)=\left(-3.2\pm 4.7\pm 2.1\right)\%,\\ {}\begin{array}{c}{\mathcal{A}}_{CP}\left({D}^{+}\to {\pi}^{+}\eta \right)=\left(-0.2\pm 0.8\pm 0.4\right)\%,\\ {}{\mathcal{A}}_{CP}\left({D}^{+}\to {K}^{+}\eta \right)=\left(-6\pm 10\pm 4\right)\%,\\ {}\begin{array}{c}{\mathcal{A}}_{CP}\left({D}_s^{+}\to {K}^{+}{\pi}^0\right)=\left(-0.8\pm 3.9\pm 1.2\right)\%,\\ {}\begin{array}{c}{\mathcal{A}}_{CP}\left({D}_s^{+}\to {\pi}^{+}\eta \right)=\left(0.8\pm 0.7\pm 0.5\right)\%,\\ {}{\mathcal{A}}_{CP}\left({D}_s^{+}\to {K}^{+}\eta \right)=\left(0.9\pm 3.7\pm 1.1\right)\%,\end{array}\end{array}\end{array}\end{array}}$where the first uncertainties are statistical and the second systematic. These results are consistent with no CP violation and mostly constitute the most precise measurements of ${\mathcal{A}}_{CP}$ in these decay modes to date.[graphic not available: see fulltext