Neoadjuvant Chemotherapy Versus Upfront Surgery for Resectable Pancreatic Adenocarcinoma: An Updated Nationwide Study.

OBJECTIVE: The objective of this study was to assess the association of survival with neoadjuvant chemotherapy (NAC) in resectable pancreatic adenocarcinoma (PDAC). BACKGROUND: The early control of potential micrometastases and patient selection using NAC has been advocated for patients with PDAC. However, the role of NAC for resectable PDAC remains unclear. METHODS: Patients with clinical T1 and T2 PDAC were identified in the National Cancer Database from 2010 to 2017. Kaplan-Meier estimates, and Cox regression models were used to compare survival. To address immortal time bias, landmark analysis was performed. Interactions between preoperative factors and NAC were investigated in subgroup analyses. A propensity score analysis was performed to compare survival between multiagent NAC and upfront surgery. RESULTS: In total, 4041 patients were treated with upfront surgery and 1,175 patients were treated with NAC (79.4% multiagent NAC, 20.6% single-agent NAC). Using a landmark time of 6 months after diagnosis, patients treated with multiagent NAC had longer median overall survival compared with upfront surgery and single-agent NAC. (35.8 vs 27.1 vs 27.4 mo). Multiagent NAC was associated with lower mortality rates compared with upfront surgery (adjusted hazard ratio, 0.77; 95% CI, 0.70-0.85), whereas single-agent NAC was not. The association of survival with multiagent NAC were consistent in analyses using the matched data sets. Interaction analysis revealed that the association between multiagent NAC and a lower mortality rate did not significantly differ across age, facility type, tumor location, CA 19-9 levels, and clinical T/N stages. CONCLUSIONS: The findings suggest that multiagent NAC followed by resection is associated with improved survival compared with upfront surgery.

Long distance multiplexed quantum teleportation from a telecom photon to a solid-state qubit.

Quantum teleportation is an essential capability for quantum networks, allowing the transmission of quantum bits (qubits) without a direct exchange of quantum information. Its implementation between distant parties requires teleportation of the quantum information to matter qubits that store it for long enough to allow users to perform further processing. Here we demonstrate long distance quantum teleportation from a photonic qubit at telecom wavelength to a matter qubit, stored as a collective excitation in a solid-state quantum memory. Our system encompasses an active feed-forward scheme, implementing a conditional phase shift on the qubit retrieved from the memory, as required by the protocol. Moreover, our approach is time-multiplexed, allowing for an increase in the teleportation rate, and is directly compatible with the deployed telecommunication networks, two key features for its scalability and practical implementation, that will play a pivotal role in the development of long-distance quantum communication.

Evaluation of Survival Following Surgical Resection for Small Nonfunctional Pancreatic Neuroendocrine Tumors.

Importance: The number of patients with small nonfunctional pancreatic neuroendocrine tumors (NF-PanNETs) is increasing. However, the role of surgery for small NF-PanNETs remains unclear. Objective: To evaluate the association between surgical resection for NF-PanNETs measuring 2 cm or smaller and survival. Design, Setting, and Participants: This cohort study used data from the National Cancer Database and included patients with NF-pancreatic neuroendocrine neoplasms who were diagnosed between January 1, 2004, and December 31, 2017. Patients with small NF-PanNETs were divided into 2 groups: group 1a (tumor size, ≤1 cm) and group 1b (tumor size, 1.1-2.0 cm). Patients without information on tumor size, overall survival, and surgical resection were excluded. Data analysis was performed in June 2022. Exposures: Patients with vs without surgical resection. Main Outcomes and Measures: The primary outcome was overall survival of patients in group 1a or group 1b who underwent surgical resection compared with those who did not, which was evaluated using Kaplan-Meier estimates and multivariable Cox proportional hazards regression models. Interactions between preoperative factors and surgical resection were analyzed with a multivariable Cox proportional hazards regression model. Results: Of the 10 504 patients with localized NF-PanNETs identified, 4641 were analyzed. These patients had a mean (SD) age of 60.5 (12.7) years and included 2338 males (50.4%). The median (IQR) follow-up time was 47.1 (28.2-71.6) months. In total, 1278 patients were in group 1a and 3363 patients were in group 1b. The surgical resection rates were 82.0% in group 1a and 87.0% in group 1b. After adjustment for preoperative factors, surgical resection was associated with longer survival for patients in group 1b (hazard ratio [HR], 0.58; 95% CI, 0.42-0.80; P < .001) but not for patients in group 1a (HR, 0.68; 95% CI, 0.41-1.11; P = .12). In group 1b, interaction analysis found that age of 64 years or younger, absence of comorbidities, treatment at academic institutions, and distal pancreatic tumors were factors associated with increased survival after surgical resection. Conclusions and Relevance: Findings of this study support an association between surgical resection and increased survival in select patients with NF-PanNETs measuring 1.1 to 2.0 cm who were younger than 65 years, had no comorbidities, received treatment at academic institutions, and had tumors of the distal pancreas. Future investigations of surgical resection for small NF-PanNETs that include the Ki-67 index are warranted to validate these findings.

Association of Adjuvant Chemotherapy in Patients With Resected Pancreatic Adenocarcinoma After Multiagent Neoadjuvant Chemotherapy.

Importance: The total number of patients with pancreatic ductal adenocarcinoma (PDAC) who receive neoadjuvant chemotherapy (NAC) is increasing. However, the added role of adjuvant chemotherapy (AC) in these patients remains unknown. Objective: To evaluate the association of AC with overall survival (OS) in patients with PDAC who received multiagent NAC followed by curative-intent surgery. Design, Setting, and Participants: This retrospective, matched-cohort study used data from the National Cancer Database and included patients with PDAC diagnosed between 2010 and 2018. The study included patients at least 18 years of age who received multiagent NAC followed by surgical resection and had available records of the pathological findings. Patients were excluded if they had clinical or pathological stage IV disease or died within 90 days of their operation. Exposures: All included patients received NAC and underwent resection for primary PDAC. Some patients received adjuvant chemotherapy. Main Outcomes and Measures: The main outcome was the OS of patients who received AC (AC group) vs those who did not (non-AC group). Interactions between pathological findings and AC were investigated in separate multivariable Cox regression models. Results: In total, 1132 patients (mean [SD] age, 63.5 [9.4] years; 577 [50.1%] male; 970 [85.7%] White) were included, 640 patients in the non-AC group and 492 patients in the AC group. After being matched by propensity score according to demographic and pathological characteristics, 444 patients remained in each group. The multivariable Cox regression model adjusted for all covariates revealed an association between AC and improved survival (hazard ratio, 0.71; 95% CI, 0.59-0.85; P < .001). Subgroup interaction analysis revealed that AC was significantly associated with better OS (26.6 vs 21.2 months; P = .002), but the benefit varied by age, pathological T category, and tumor differentiation. Of note, AC was associated with better survival in patients with any pathological N category and positive margin status. Conclusions and Relevance: In this cohort study, AC following multiagent NAC and resection in patients with PDAC was associated with significant survival benefit compared with that in patients who did not receive AC. These findings suggest that patients with aggressive tumors may benefit from AC to achieve prolonged survival, even after multiagent NAC and curative-intent resection.

Storage and analysis of light-matter entanglement in a fiber-integrated system.

The deployment of a full-fledged quantum internet poses the challenge of finding adequate building blocks for entanglement distribution between remote quantum nodes. A practical system would combine propagation in optical fibers with quantum memories for light, leveraging on the existing communication network while featuring the scalability required to extend to network sizes. Here, we demonstrate a fiber-integrated quantum memory entangled with a photon at telecommunication wavelength. The storage device is based on a fiber-pigtailed laser-written waveguide in a rare earth-doped solid and allows an all-fiber stable addressing of the memory. The analysis of the entanglement is performed using fiber-based interferometers. Our results feature orders-of-magnitude advances in terms of storage time and efficiency for integrated storage of light-matter entanglement and constitute a substantial step forward toward quantum networks using integrated devices.

Entanglement between a Telecom Photon and an On-Demand Multimode Solid-State Quantum Memory.

Entanglement between photons at telecommunication wavelengths and long-lived quantum memories is one of the fundamental requirements of long-distance quantum communication. Quantum memories featuring on-demand readout and multimode operation are additional precious assets that will benefit the communication rate. In this Letter, we report the first demonstration of entanglement between a telecom photon and a collective spin excitation in a multimode solid-state quantum memory. Photon pairs are generated through widely nondegenerate parametric down-conversion, featuring energy-time entanglement between the telecom-wavelength idler and a visible signal photon. The latter is stored in a Pr^{3+}:Y_{2}SiO_{5} crystal as a spin wave using the full atomic frequency comb scheme. We then recall the stored signal photon and analyze the entanglement using the Franson scheme. We measure conditional fidelities of 92(2)% for excited-state storage, enough to violate a Clauser-Horne-Shimony-Holt inequality, and 77(2)% for spin-wave storage. Taking advantage of the on-demand readout from the spin state, we extend the entanglement storage in the quantum memory for up to 47.7 µs, which could allow for the distribution of entanglement between quantum nodes separated by distances of up to 10 km.

Long-term complete response in metastatic poorly-differentiated neuroendocrine rectal carcinoma with a multimodal approach: A case report.

BACKGROUND: Neuroendocrine gastrointestinal tumors (NETs) are rare and have different natural behaviors. Surgery is the gold standard treatment for local disease while radiotherapy has been demonstrated to be ineffective. Poorly differentiated neuroendocrine carcinomas (NECs) represent only 5%-10% of digestive NETS. Due to aggressive growth and rapid metastatic diffusion, early diagnosis and a multidisciplinary approach are mandatory. The role of surgery and radiotherapy in this setting is still debated, and chemotherapy remains the treatment of choice. CASE SUMMARY: A 42-year-old male with an ulcerated bleeding rectal lesion was diagnosed with a NEC G3 (Ki67 index > 90%) on May 2015 and initially treated with 3 cycles of first-line chemotherapy, but showed early local progressive disease at 3 mo and underwent sphincter-sparing open anterior low rectal resection. In September 2015, the first post-surgery total-body computed tomography (CT) scan showed an early pelvic disease relapse. Therefore, systemic chemotherapy with FOLFIRI was started and the patient obtained only a partial response. This was followed by pelvic radiotherapy (50 Gy). On April 2016, a CT scan and 18F-fluorodeoxyglucose positron emission tomography imaging showed a complete response (CR) of the pelvic lesion, but pathological abdominal inter-aortocaval lymph nodes were observed. Due to disease progression of abdominal malignant nodes, the patient received radiotherapy at 45 Gy, and finally obtained a CR. As of January 2021, the patient has no symptoms of relapse and no late toxicity after chemotherapy or radiotherapy. CONCLUSION: This case demonstrates how a multimodal approach can be successful in obtaining long-term CR in metastatic sites in patients with high grade digestive NECs.

Telecom-heralded entanglement between multimode solid-state quantum memories.

Future quantum networks will enable the distribution of entanglement between distant locations and allow applications in quantum communication, quantum sensing and distributed quantum computation1. At the core of this network lies the ability to generate and store entanglement at remote, interconnected quantum nodes2. Although various remote physical systems have been successfully entangled3-12, none of these realizations encompassed all of the requirements for network operation, such as compatibility with telecommunication (telecom) wavelengths and multimode operation. Here we report the demonstration of heralded entanglement between two spatially separated quantum nodes, where the entanglement is stored in multimode solid-state quantum memories. At each node a praseodymium-doped crystal13,14 stores a photon of a correlated pair15, with the second photon at telecom wavelengths. Entanglement between quantum memories placed in different laboratories is heralded by the detection of a telecom photon at a rate up to 1.4 kilohertz, and the entanglement is stored in the crystals for a pre-determined storage time up to 25 microseconds. We also show that the generated entanglement is robust against loss in the heralding path, and demonstrate temporally multiplexed operation, with 62 temporal modes. Our realization is extendable to entanglement over longer distances and provides a viable route towards field-deployed, multiplexed quantum repeaters based on solid-state resources.

Enhancing safety of laparoscopic surgery in COVID-19 era: clinical experience with low-cost filtration devices.

BACKGROUND: Surgery in the era of the current COVID-19 pandemic has been curtailed and restricted to emergency and certain oncological indications, and requires special attention concerning the safety of patients and health care personnel. Desufflation during or after laparoscopic surgery has been reported to entail a potential risk of contamination from 2019-nCoV through the aerosol generated during dissection and/or use of energy-driven devices. In order to protect the operating room staff, it is vital to filter the released aerosol. METHODS: The assemblage of two easily available and low-cost filter systems to prevent potential dissemination of Coronavirus via the aerosol is described. RESULTS: Forty-nine patients underwent laparoscopic surgeries with the use of one of the two described tools, both of which proved to be effective in smoke evacuation, without affecting laparoscopic visualization. CONCLUSION: The proposed systems are cost-effective, easily assembled and reproducible, and provide complete viral filtration during intra- and postoperative release of CO2.

Stable, single-photon emitter in a thin organic crystal for application to quantum-photonic devices.

Single dibenzoterrylene (DBT) molecules offer great promise as bright, reliable sources of single photons on demand, capable of integration into solid-state devices. It has been proposed that DBT in anthracene might be placed close to an optical waveguide for this purpose, but so far there have been no demonstrations of sufficiently thin crystals, with a controlled concentration of the dopant molecules. Here we present a method for growing very thin anthracene crystals from super-saturated vapour, which produces crystals of extreme flatness and controlled thickness. We show how this crystal can be doped with an adjustable concentration of dibenzoterrylene (DBT) molecules and we examine the optical properties of these molecules to demonstrate their suitability as quantum emitters in nanophotonic devices. Our measurements show that the molecules are available in the crystal as single quantum emitters, with a well-defined polarisation relative to the crystal axes, making them amenable to alignment with optical nanostructures. We find that the radiative lifetime and saturation intensity vary little within the crystal and are not in any way compromised by the unusual matrix environment. We show that a large fraction of these emitters can be excited more than 1012 times without photo-bleaching, making them suitable for real applications.

Growth of optical-quality anthracene crystals doped with dibenzoterrylene for controlled single photon production.

Dibenzoterrylene (DBT) molecules within a crystalline anthracene matrix show promise as quantum emitters for controlled, single photon production. We present the design and construction of a chamber in which we reproducibly grow doped anthracene crystals of optical quality that are several mm across and a few µm thick. We demonstrate control of the DBT concentration over the range 6-300 parts per trillion and show that these DBT molecules are stable single-photon emitters. We interpret our data with a simple model that provides some information on the vapour pressure of DBT.

Quantum process nonclassicality.

We propose a definition of nonclassicality for a single-mode quantum-optical process based on its action on coherent states. If a quantum process transforms a coherent state to a nonclassical state, it is verified to be nonclassical. To identify nonclassical processes, we introduce a representation for quantum processes, called the process-nonclassicality quasiprobability distribution, whose negativities indicate nonclassicality of the process. Using this distribution, we derive a relation for predicting nonclassicality of the output states for a given input state. We experimentally demonstrate our method by considering the single-photon addition as a nonclassical process and predicting nonclassicality of the output state for an input thermal state.