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Simple Summary: Currently, it is unclear which kind of axillary staging surgery breast cancer patients with lymph node metastasis should receive after neoadjuvant chemotherapy. For decades, these patients have been treated with a full axillary lymph node dissection, even if they converted to clinical node negativity. However, the removal of a large number of lymph nodes during the procedure can increase arm morbidity and impact quality of life. Therefore, several studies investigated less radical surgical strategies in this setting, such as sentinel lymph node biopsy or targeted axillary dissection, i.e., removal of a previously marked node combined with sentinel node removal. In this review, we summarize current evidence on the different surgical techniques and compare national and international recommendations. We show that many questions regarding oncological safety of different surgery types and the optimal marking technique remain unanswered and present the multinational prospective cohort study AXSANA that will address these open issues.
Abstract: In the last two decades, surgical methods for axillary staging in breast cancer patients have become less extensive, and full axillary lymph node dissection (ALND) is confined to selected patients. In initially node-positive patients undergoing neoadjuvant chemotherapy, however, the optimal management remains unclear. Current guidelines vary widely, endorsing different strategies. We performed a literature review on axillary staging strategies and their place in international recommendations. This overview defines knowledge gaps associated with specific procedures, summarizes currently ongoing clinical trials that address these unsolved issues, and provides the rationale for further research. While some guidelines have already implemented surgical de-escalation, replacing ALND with, e.g., sentinel lymph node biopsy (SLNB) or targeted axillary dissection (TAD) in cN+ patients converting to clinical node negativity, others recommend ALND. Numerous techniques are in use for tagging lymph node metastasis, but many questions regarding the marking technique, i.e., the optimal time for marker placement and the number of marked nodes, remain unanswered. The optimal number of SLNs to be excised also remains a matter of debate. Data on oncological safety and quality of life following different staging procedures are lacking. These results provide the rationale for the multinational prospective cohort study AXSANA initiated by EUBREAST, which started enrollment in June 2020 and aims at recruiting 3000 patients in 20 countries (NCT04373655; Funded by AGO-B, Claudia von Schilling Foundation for Breast Cancer Research, AWOgyn, EndoMag, Mammotome, and MeritMedical).
In dieser Arbeit wurde zunächst schrittweise das Vorgehen beim Bau der TRD Prototypkammern , sowie die Maßnahmen zur Verbesserung der Kammerstabilität erklärt, um sicherzustellen, dass die erhobenen Messdaten zuverlässig sind. Es ist an dieser Stelle nochmals hervorzuheben, dass bereits kleine Veränderungen in der Bauweise einen großen Einfluss auf die Kammerstabilität haben.
Es wurde mit der Kammer 3 der Anodenstrom, die deponierte Photonenenergie und die Clusterrate gemessen. Anschließend wurden diese Daten ausgewertet und aus den Ergebnissen die Gasverstärkung berechnet. Die Auswertung bestätigt, dass die Kammer im Proportionalbereich betrieben wurde. Nach dem Vergleich der Gasverstärkungsfaktoren der Messung mit den simulierten Werten, zeigt sich dass die Messungen stärker als erwartet von den simulierten Werten abweichen.
Für weitere, genauere Aussagen wäre es interessant die Ergebnisse dieser Arbeit durch modifizierte Messungen zu uberprüfen. Dabei könnte der Einfluss verschiedener Gasdrucke innerhalb und außerhalb der Kammer sowie die Variation der Raumtemperatur auf die Gasverstärkung explizit untersucht werden. Außerdem wäre es von großem Interesse, Messungen mit verschiedenen Ar und CO2 und Xe und CO2 Mischverhältnissen durchzuführen, da der TRD im CBM Experiment mit Xe und CO2 betrieben werden soll, und der Gasverstärkungsfaktor ausschlaggebend für die angelegte Anodenspannung im laufenden Betrieb sein wird.
The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at sqrt{s}=7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L_int = 5.6nb-1. The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p_t>1.3 GeV/c and rapidity |y|<0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the Psi(2S) and Csi_c resonances, is sigma_prompt-J/psi(pt > 1.3 GeV/c, |y| < 0.9) = 8.3 +- 0.8(stat.) +- 1.1(syst.) + 1.5 - 1.4(syst. pol.) micro barn. The cross section for the production of b-hadrons decaying to J/psi with p_t>1.3 GeV/c and |y|<0.9 is sigma_{J/psi<-h_B} = 1.46 +- 0.38(stat.) + 0.26 -0.32(syst.) micro barn. The results are compared to QCD model predictions. The shape of the p_t and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b-bbar pair total cross section and dsigma/dy at mid-rapidity.