Abstract P3-18-02: Breast conservation plus radiotherapy provides superior survival benefit than mastectomy in triple negative breast cancer: A propensity matched national cancer database analysis

Background: Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with a higher risk of locoregional and distance recurrence. Consequently, this population was considered poor candidate for breast conservation (BCT). Our study aim was to determine whether BCT plus radiotherapy (RT) was equivalent to mastectomy for TNBC after adjustment of selection bias of demographic and clinical characteristics. Methods: The National Cancer Database was queried for women diagnosed as primary unilateral invasive clinical T1-2N0-2 TNBC from 2004-2016. Patients who underwent mastectomy or breast conservation (partial mastectomy plus radiation) were included. A 1:1 propensity match with replacement was performed to compare breast conservation vs. mastectomy. Overall survival was analyzed using stratified multivariable Cox proportional hazard regression analysis.Results: Of 59,599 clinical T1-2N0-2 TNBC patients, 26,325 (44.2%) underwent mastectomy and 33,274 (55.8%) were treated with BCT. BCT patients were older (median age 59 vs. 54, p<0.001), had smaller tumors (cT1 61.7% vs. 42.9%, p<0.001) and node negative (cN0 85.8% vs. 73.7%, p<0.001). Propensity matching reduced the bias between mastectomy and breast conservation groups and generated 30,980 pairs for analysis. Median follow-up times were 41 months (range 6.97-95.8) and 39 months (range, 0.62 -94.06) for BCT and mastectomy groups, respectively. After matching, BCT+RT was associated with significantly higher OS compared to mastectomy ( 86.8% vs. 79.7%, p<0.001). The survival advantage was also present in multivariate cox regression after controlling age, race, insurance, facility type, clinical T and clinical N stage.Conclusions: Using both propensity matching and multivariate cox regression controlling for potential confounders, BCT+RT survival was superior to mastectomy in a retrospective analysis of a large cancer database.

Citation Format: Lifen Cao, Christopher W Towe, Megan E Miller, Alberto J Montero, Robert Shenk. Breast conservation plus radiotherapy provides superior survival benefit than mastectomy in triple negative breast cancer: A propensity matched national cancer database analysis [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 P3-18-02.

Abstract PD7-08: Less is not necessarily more: A propensity matched national analysis on effect and outcome of sentinel lymph node biopsy omission

Background: Routine sentinel lymph node biopsy (SLNB) has been recommended against by Choosing Wisely© Foundation due to its low value in clinical node negative, hormone receptor positive breast cancer patients age≥70 years old. We used the National Cancer Database (NCDB) to examine the effect of SLNB omission and outcomes in this population. We hypothesized that SLNB would be beneficial in this population.Methods: The National Cancer Database was queried for women diagnosed with primary unilateral invasive clinical stage T1N0M0 hormone receptor positive, HER-2 negative breast cancer from 2012-2017. Patients age ≥ 70 years old with Charlson Score ≥1 who underwent partial mastectomy and received hormonal therapy were included in the study cohort. Patients received neoadjuvant therapy or underwent upfront axillary lymph node dissection (ALND) were excluded. A 1:3 propensity match with replacement was performed to compare SLNB omission vs. SLNB group controlling age, race, comorbidities, insurance and facility. Overall survival was analyzed using stratified multivariable Cox proportional hazard regression analysis.Results: Of 14,150 patients, 1,928 (13.6%) omitted SLNB and 12,222 (86.4%) underwent SLNB, including 1,545/12,222 (12.6%) who proceeded to ALND. Central portion tumor location (OR=1.77, P=0.001), clinical T1c (OR= 2.49, P<0.001) and lymph-vascular invasion (OR=7.46, P<0.001) were significant associated with positive pathological lymph node involvement in SLNB group. Among the 1,397 patients of positive nodal status with SLNB, 87.7% received radiation therapy and 19.3% received chemotherapy. Propensity matching reduced bias between the groups, generating 1,903 SLNB omission and 5,703 SLNB patients for analysis. After match, the SLNB omission group was less likely to receive chemotherapy (1.1% vs. 3.0%, p<0.001) or radiation therapy (28.9% vs. 60.8%, p<0.001). Omitting SLNB was associated with inferior overall survival (3-year 83.7% vs. 90.6%, 5-year 66.4% vs. 76.1%, p<0.001). Omitting SLNB was also associated with inferior survival in multivariate cox regression (HR=1.64, p<0.001). Chemotherapy (OR=0.51, p=0.020) and radiation therapy (OR=0.85, P=0.007) were associated with superior overall survival.Conclusions: SLNB remains to be of importance in cT1N0M0 HR+HER2- patients of age 70 years. Pathologic staging affects decisions on adjuvant treatment and SLNB omission is associated with inferior survival. In this population, SLNB might need to be re-implemented, especially in patients with high likelihood of nodal involvement.

Citation Format: Lifen Cao, Megan E Miller, Luke D Rothermel, Alberto J Montero, Christopher W Towe, Robert Shenk. Less is not necessarily more: A propensity matched national analysis on effect and outcome of sentinel lymph node biopsy omission [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 PD7-08.

[Utility of GPR68 and TIL in TPF-induced chemotherapy and prognosis evaluation in middle-advanced hypopharyngeal squamous cell carcinoma]

Objective: To evaluate the roles of G Protein-Coupled Receptor 68 (GPR68) and tumor infiltrating lymphocytes (TIL) in TPF-(paclitaxel, cisplatin and 5-fluorouracil) induced chemotherapy for middle-advanced hypopharyngeal squamous cell carcinomas. Methods: A total of 31 patients with middle-advanced hypopharyngeal squamous cell carcinoma before TPF-inducted chemotherapy were enrolled from September 2012 to November 2017 in Beijing Tongren Hospital, Capital Medical University, including 28 males and 3 females, aged 43 to 71 years old. The expression of GPR68 and tumor infiltrating CD4⁺and CD8⁺T cells before chemotherapy was detected by immunohistochemical staining, and the relationships between GPR68 expression and clinical features, chemotherapy efficacy and overall survival (OS) were analyzed using t-test. Results: After 3 cycles of chemotherapy, there were 4, 14, 10 and 3 patients respectively with complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). The positive rates of GPR68 and CD8 were 25% and 40% respectively in the effective group (CR+PR), while 50% and 15% in the ineffective group (SD+PD), with statistically significant differences between two groups (t=5.17 and 12.86,P<0.001). Linear regression analysis showed that GPR68 was negatively correlated with CD8⁺T cells (r=-0.64,P<0.001). There was no significant correlation between the CD4 expression and TPF efficacy (P>0.05). The mean OS was 12.5 months in patients with high-expressed GPR68 and 25.0 months in patients with low-expressed GPR68, with a statistically significant difference (P=0.005). And mean OS was 25.0 months in patients with high-expressed CD8 and 14.5 months in low-expressed CD8, with a statistically significant difference (HR=2.58, P=0.019). Cox regression analysis showed that GPR68 and CD8⁺T cells were significant prognostic factors (OR(95%CI)=3.27(2.46-5.97) and 1.53(0.78-1.82), all P<0.05), while CD4 had no significant effect on prognosis (P>0.05). Conclusion: GPR68 and CD8⁺T cells are expected to be biomarkers for evaluating the efficacy and prognosis of TPF-induced chemotherapy in patients with middle-advanced hypopharyngeal squamous cell carcinoma.

[Clinical characteristics of human adenovirus infection in hospitalized children with acute respiratory infection in Beijing]

Objective: To compare the clinical characteristics of different types of human adenovirus (HAdV) infection in hospitalized children with acute respiratory infection in Beijing, and to clarify the clinical necessity of adenovirus typing. Methods: In a cross-sectional study, 9 022 respiratory tract specimens collected from hospitalized children with acute respiratory infection from November 2017 to October 2019 in Affiliated Children's Hospital, Capital Institute of Pediatrics were screened for HAdV by direct immunofluorescence (DFA) and (or) nucleic acid detection. Then the Penton base, Hexon and Fiber gene of HAdV were amplified from HAdV positive specimens to confirm their HAdV types by phylogenetic tree construction. Clinical data such as laboratory results and imaging data were analyzed for children with predominate type HAdV infection using t, U, or χ² test. Results: There were 392 cases (4.34%) positive for HAdV among 9 022 specimens from hospitalized children with acute respiratory infection. Among those 205 cases who were successfully typed, 131 were male and 74 were female, age of 22.6 (6.7, 52.5) months,102 cases (49.76%) were positive for HAdV-3 and 86 cases (41.95%), HAdV-7, respectively, while 17 cases were confirmed as HAdV-1, 2, 4, 6, 14 or 21. In comparison of clinical characteristics between the predominate HAdV type 7 and 3 infection, significant differences were shown in proportions of children with wheezing (10 cases (11.63%) vs. 25 cases (24.51%)), white blood cell count >15 ×10⁹/L (4 cases (4.65%) vs.14 cases (13.73%)), white blood cell count <5×10⁹/L (26 cases (30.23%) vs.11 cases (10.78%)), procalcitonin level>0.5 mg/L (43 cases (50.00%) vs. 29 cases (28.43%)), multilobar infiltration (45 cases (52.33%) vs.38 cases (37.25%)), pleural effusion (23 cases (26.74%) vs. 10 cases (9.80%)), and severe adenovirus pneumonia (7 cases (8.14%) vs. 2 cases (1.96%)) with χ²=5.11, 4.44, 11.16, 9.19, 4.30, 9.25, 3.91 and P=0.024, 0.035, 0.001, 0.002, 0.038, 0.002, 0.048, respectively, and also in length of hospital stay (11 (8, 15) vs. 7 (5, 13) d, Z=3.73, P<0.001). Conclusions: HAdV-3 and 7 were the predominate types of HAdV infection in hospitalized children with acute respiratory tract infection in Beijing. Compared with HAdV-3 infection, HAdV-7 infection caused more obvious inflammatory reaction, more severe pulmonary symptoms, longer length of hospital stay, suggesting the clinical necessity of further typing of HAdVs.

Measurement of Differential Branching Fractions of Inclusive B→X_{u}ℓ^{+}ν_{ℓ} Decays

The first measurements of differential branching fractions of inclusive semileptonic B→X_{u}ℓ^{+}ν_{ℓ} decays are performed using the full Belle data set of 711  fb^{-1} of integrated luminosity at the ϒ(4S) resonance and for ℓ=e, μ. With the availability of these measurements, new avenues for future shape-function model-independent determinations of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| can be pursued to gain new insights in the existing tension with respect to exclusive determinations. The differential branching fractions are reported as a function of the lepton energy, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic B→X_{c}ℓ^{+}ν_{ℓ} decays and other processes, and corrected for resolution and acceptance effects.

Precise Measurement of the D^{0} and D^{+} Lifetimes at Belle II

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72  fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst)  fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst)  fs, are the most precise to date and are consistent with previous determinations.

The miR-1906 mimic attenuates bone loss in osteoporosis by down-regulating the TLR4/MyD88/NF-κB pathway

In this study, the ability of microRNA-1906 (miR-1906) to attenuate bone loss in osteoporosis was evaluated by measuring the effects of a miR-1906 mimic and inhibitor on the cellular toxicity and cell viability of MC3T3-E1 cells. Bone marrow-derived macrophage (BMM) cells were isolated from female mice, and tartrate-resistant acid phosphatase signalling was performed in miR-1906 mimic-treated, receptor-activated nuclear factor kappa-B (NF-κB) ligand (RANKL)-induced osteoclasts. In-vivo, osteoporosis was induced by ovariectomy (OVX). Rats were treated with 500 nmol/kg of the miR-1906 mimic via intrathecal administration for 10 consecutive days following surgery. The effect of the miR-1906 mimic on bone mineral density (BMD) in OVX rats was observed in the whole body, lumbar vertebrae and femur. Levels of biochemical parameters and cytokines in the serum of miR-1906 mimic-treated OVX rats were analysed. The mRNA expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), p-38 and NF-κB in tibias of osteoporotic rats (induced by ovariectomy) was observed using quantitative reverse-transcription polymerase chain reaction. Treatment with the miR-1906 mimic reduced cellular toxicity and enhanced the cell viability of MC3T3-E1 cells. Furthermore, osteoclastogenesis in miR-1906 mimic-treated, RANKL-induced osteoclast cells was reduced, whereas the BMD in the miR-1906 mimic-treated group was higher than in the OVX group of rats. Treatment with the miR-1906 mimic also increased levels of biochemical parameters and cytokines in the serum of ovariectomised rats. Finally, mRNA expression levels of TLR4, MyD88, p-38 and NF-κB were lower in the tibias of miR-1906 mimic-treated rats than in those of OVX rats. In conclusion, the miR-1906 mimic reduces bone loss in rats with ovariectomy-induced osteoporosis by regulating the TLR4/MyD88/NF-κB pathway.

[Clinical analysis of two brothers with Imerslund-Gräsbeck syndrome]

The clinical data of two children with Imerslund-Gräsbeck syndrome (IGS) who were admitted to the First Affiliated Hospital of Zhengzhou University in August 2019 was analyzed retrospectively. The two cases were siblings, aged 8 years and 8 months and 6 years and 2 months, respectively. These two boys had megaloblastic anemia, low level of vitamin B₁₂, hyperhomocysteinemia, accompanied by proteinuria and renal tubular injury, while they showed normal folate level and renal function. Blood tandem mass spectrometry and urine organic acid analysis suggested methylmalonic acidemia (MMA). The initial diagnosis was MMA with homocysteinemia. No known pathogenic gene mutation related to MMA was found by gene sequencing. Compound heterozygous variants of amnionless (AMN) gene were detected: c.43+5G>A and c.C717G. The corrected diagnosis was IGS. Both brothers were treated with long-term intramuscular injection of vitamin B₁₂. After follow-up for one year, these two cases had no clinical symptoms, and their blood indicators remained normal, but proteinuria and renal tubular injury persisted. Blood tandem mass spectrometry and urine organic acid analysis alone may easily lead to misdiagnosis, but combined with genetic testing can improve the accuracy of diagnosis of IGS. Lifelong parenteral vitamin B₁₂ replacement therapy can effectively reverse the clinical and biochemical results, but is uncertain in alleviating albuminuria and renal tubule injury. It's necessary to monitor the renal function regularly.

Search for B^{+}→K^{+}νν[over ¯] Decays Using an Inclusive Tagging Method at Belle II

A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63  fb^{-1} collected at the ϒ(4S) resonance and a sample of 9  fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B^{+}→K^{+}νν[over ¯] of 4.1×10^{-5} is set at the 90% confidence level.

Analytical and Clinical Performance Evaluation of ARK Fentanyl II Assay on Beckman Coulter AU System

Introduction/Objective

Drugs of abuse, specifically opioids, have been in recent years an important focus in both medicine and media due to the ‘opioid epidemic’ and large numbers of overdose deaths. Synthetic opioids such as fentanyl have contributed to this epidemic. The CDC reports that of roughly 50,000 opioid overdose deaths in 2019, nearly 73% were due to synthetic opioids. The objective of this study is to assess the analytical and clinical performance of the Fentanyl II Assay by ARK Diagnostics, Inc.

Methods/Case Report

Fentanyl was qualitatively determined by the ARK Fentanyl II Assay, a homogenous enzyme immunoassay based on competition between drug in the specimen and drug labeled with recombinant glucose-6- phosphate dehydrogenase (rG6PDH) for antibody binding sites. The presence of drug in urine increases enzyme activity, which converts nicotinamide adenine dinucleotide (NAD) to NADH in the presence of glucose-6-phosphate, resulting in an absorbance change measured by spectrophotometry. The evaluation was performed following CLSI guidelines. The analytical performance was evaluated for accuracy and precision.

Results (if a Case Study enter NA)

To evaluate the accuracy, twelve positive and eight negative specimens were tested by the ARK immunoassay performed on two Beckman Coulter instruments (AU480 and AU680) and by LC- MS/MS. The results from both instruments showed 100% agreement with the results from LC-MS/MS. On instrument AU480, the within-run CVs were 18.0% at the level of 22.510 ng/mL and 0.8% at the level of 552.628 ng/mL. The between-run CVs were 8.8% at the level of 68.928 ng/mL and 3.7% at the level of 158.947 ng/mL. On instrument AU680, the within-run CVs were 273.4% at the level of 1.052 ng/mL and 0.8% at the level of 523.788 ng/mL. The between-run CVs were 7.8% at the level of 53.779 ng/mL and 3.1% at the level of 145.263 ng/mL. In May 2021, 2,075 fentanyl assays were run at UAB. Of those, 476 returned a positive result with a positive rate of 22.9%, and 1,599 were negative with a negative rate of 77.1%. One positive result was confirmed by LC-MS/MS as negative for fentanyl but positive for norfentanyl, a metabolite of fentanyl. The clinical specificity was 99.9% and sensitivity was 100%.

Conclusion

In Conclusion, the ARK fentanyl Assay II on Beckman Coulter AU system has good accuracy, sensitivity and specificity. The precision at medium and high levels are good. However, the precision at low level needs to be improved.

Adjuvant trastuzumab with or without chemotherapy in stage 1 pT1N0 HER2+ breast cancer: a National Cancer Database analysis

PURPOSE

Approximately 20% of all breast cancers (BC) are HER2 amplified. In the APT trial, weekly paclitaxel/trastuzumab in node negative HER2+ BC with tumors < 3 cm was associated with a 7-year invasive disease-free survival of 93%. However, this was in the context of a non-randomized trial, and for pT1N0 HER2+ BC it remains unclear whether HER2 monotherapy would provide similar clinical outcomes to chemo-HER2 therapy. We hypothesized that adjuvant chemo-HER2 therapy would be associated with a modestly improved overall survival compared to HER2 monotherapy in patients with tumors < 2 cm.

METHODS

In the National Cancer Database (2004-2017), patients with a primary diagnosis of pT1N0M0 HER2+ BC, were separated into two groups: (i) HER2 monotherapy, i.e., trastuzumab, and (ii) chemo-HER2 therapy. A 3:1 propensity match was performed to balance patient selection bias between the two different cohorts. Long-term overall survival (OS) was compared between both groups.

RESULTS

A total of 23,281 patients met the criteria. 22,268 (96.7%) received chemo-HER2 therapy and 1013 (4.4%) received HER2 monotherapy. Propensity match identified 1995 patients who received chemo-HER2 therapy, and 666 who received HER2 monotherapy. After matching, adjuvant chemo-HER2 therapy was associated with a modest survival advantage over HER2 monotherapy (5-year OS 94.1% vs. 90.6%, P = 0.041).

CONCLUSIONS

Even though there is a modest OS advantage favoring adjuvant chemo-HER2 therapy in patients with pT1N0 HER2+ BC, HER2 monotherapy was associated with 5-year OS > 90%. Therefore, in select patients who have contraindications for cytotoxic chemotherapy, or decline adjuvant chemotherapy altogether, adjuvant trastuzumab monotherapy appears to be a reasonable alternative.

Macrophage M1/M2 ratio as a predictor of pleural thickening in patients with tuberculous pleurisy

We evaluated the association between macrophage polarization and the development of pleural thickening in patients with tuberculous pleurisy. Patients with tuberculous pleurisy admitted to our hospital between October 2018 and March 2019 were prospectively recruited. Pleural fluid samples were obtained before treatment for detection of adenosine deaminase (ADA) and macrophage phenotype (M1: CD14+ CD86+; M2: CD14+ CD163+). Peripheral blood samples were subjected to interferon gamma release assay (IGRA). All subjects were administered standard anti-tuberculosis regimen (2HREZ/4HR); high-resolution CT was performed to determine pleural thickening (thickness>2mm) after completion of treatment. Pleural effusion in patients with thickened pleura had significantly more M1 but fewer M2 macrophages, and higher ADA level, as compared to those with normal pleura (P<0.05). No significant between-group difference was observed with respect to IGRA. In receiver operating characteristic (ROC) curve analysis, the optimal cut-off level of M1/M2 ratio for predicting pleural thickening was 1.149 (area under the curve: 0.842; sensitivity: 88.6%; specificity: 69.2%; positive predictive value: 86.3%; negative predictive value: 81.7%). M1/M2 ratio in the pleural fluid is a promising marker for predicting the development of pleural thickening in patients with tuberculous pleurisy. Macrophage-mediated immune response may play an important role in the pathogenesis of tuberculous pleurisy.

[Clinical characteristics of children infected with different subtypes/genotypes of human respiratory syncytial virus in Beijing from 2009 to 2017]

Objective: To explore the different clinical characteristics of children infected with different subtype/genotype of human respiratory syncytial virus (HRSV) in Beijing. Methods: Respiratory specimens for positive HRSV were randomly collected from children with acute respiratory tract infection (ARTI) in the epidemic season of HRSV from November of each year to January of the next year during 2009 and 2017. G genes of HRSV were amplified and sequenced for subtyping and genotyping by bioinformatics analysis. Clinical data were collected and analyzed. Results: Out of 590 children, 376 (63.7%) with subtype A, and 214 (36.3) with subtype B. The annual dominant subtypes of HRSV from 2009 to 2017 were B-A-A-B-AB-A-A-B-A, respectively, whilst a total of 10 genotypes were detected with 95.8% assigned to genotype ON1 and NA1 of subtype A, and genotype BA9 of subtype B. Children infected with subtype B (96 cases, 44.9%) were more likely aged 0-3 month old than those with subtype A (118 cases, 31.4%) (P=0.001), and more likely to be admitted to Intensive Care Unit(ICU) ((124 cases, 57.9%) than those with subtype A (172 cases, 45.7%)) (P=0.005). Statistical significance were shown among children infected with genotype ON1, NA1 or BA9, in the possibility of infection in children aged 0-3 month (P=0.003), proportion of admission into ICU (P=0.007), length of stay in hospital (P=0.001), and clinical outcome (P=0.001), respectively. Conclusion: Children infected with different subtype or genotype of HRSV have different clinical characteristics, which stresses the important role of the monitoring HRSV subtypes and genotypes among children.

[Da Vinci robot-assisted pylorus and vagus nerve-preserving partial gastrectomy for gastric cancer]

Objective: To investigate the safety and feasibility of Da Vinci robot-assisted pylorus and vagus nerve-preserving partial gastrectomy for gastric cancer. Methods: In this study, descriptive case series method was used to retrospectively analyze the data of 3 patients with gastric cancer who underwent Da Vinci robot-assisted pylorus and vagus nerve-preserving partial gastrectomy in the First Affiliated Hospital of Dalian Medical University from December 2020 to February 2021. The linear layout was adopted for the setting of trocar, and the co-axial direction was the line connecting the umbilicus and splenic hilum. The inferior pyloric arteries and veins need to be preserved. The center was the bifurcation of the right gastroepiploic vessel and the inferior pyloric vessel. Dissection and exposure were performed from the upper, lower, right and left sides, and ventral and dorsal sides to complete the dissection of the inferior pyloric lymph nodes. The superior border of the pancreas was treated by the right diaphragmatic crus approach, the left retroperitoneal approach and the esophageal approach to determine the distribution of the posterior vagal trunk and its branches, and to determine the anatomical relationship with the left gastric artery. The left gastric artery was cut off while the celiac branch of vagus nerve and cardia branch of left gastric artery were preserved. Lymph node dissection was performed on the lateral side of nerve fibers around the blood vessels. Result: All the 3 patients successfully completed the robotic surgery without conversion to laparoscopy or laparotomy. The operation time was (340.0±26.4) (300-390) minutes, the intraoperative blood loss was (13.3±3.3) (10-20) ml, the number of dissected lymph nodes was 26.7±3.9 (19-32), the length of pylorus canal preserved was (3.3±0.3) (3-4) cm, the distal margin was (2.3±0.3) (2-3) cm, and the proximal margin was (3.0±0.6) (2-4) cm. No postoperative complications occurred in all the 3 patients. The first flatus time was 2-3 days after operation, and the postoperative hospital stay was 6-7 days. The operation cost of the 3 patients was (40±7) (33-53) thousand yuan. Conclusion: Da Vinci robot-assisted pylorus and vagus nerve-preserving partial gastrectomy is safe and feasible.

Automatic detection of adult cardiomyocyte for high throughput measurements of calcium and contractility

Simultaneous calcium and contractility measurements on isolated adult cardiomyocytes have been the gold standard for the last decades to study cardiac (patho)physiology. However, the throughput of this system is low which limits the number of compounds that can be tested per animal. We developed instrumentation and software that can automatically find adult cardiomyocytes. Cells are detected based on the cell boundary using a Sobel-filter to find the edge information in the field of view. Separately, we detected motion by calculating the variance of intensity for each pixel in the frame through time. Additionally, it detects the best region for calcium and contractility measurements. A sensitivity of 0.66 ± 0.08 and a precision of 0.82 ± 0.03 was reached using our cell finding algorithm. The percentage of cells that were found and had good contractility measurements was 90 ± 10%. In addition, the average time between 2 cardiomyocyte calcium and contractility measurements decreased from 93.5 ± 80.2 to 15.6 ± 8.0 seconds using our software and microscope. This drastically increases throughput and provides a higher statistical reliability when performing adult cardiomyocyte functional experiments.