PD-L1 Inhibitors Combined with Thoracic Radiotherapy in First-Line Treatment of Extensive Stage Small Cell Lung Cancer: A Propensity Score-Matched, Real-World Study

PURPOSE/OBJECTIVE(S)

The CREST study showed that the addition of thoracic radiotherapy (TRT) could improve the survival of extensive stage small cell lung cancer (ES-SCLC), but whether TRT can bring survival benefit in the era of immunotherapy is controversial. This study aims to explore the efficacy and safety of adding TRT to the combination of PD-L1 inhibitors and chemotherapy.

MATERIALS/METHODS

Thepatients who received PD-L1 inhibitors combined with platinum-based chemotherapy as the first-line treatment of ES-SCLC from January 2019 to December 2021 were retrospectively collected. According to whether they received TRT, they were divided into two groups, and the follow-up analysis was performed. Propensity score matching (PSM) in with a 1:1 ratio was performed to balance the baseline characteristics of the two cohorts. The endpoints were progression-free survival (PFS) and OS.

RESULTS

A total of 211 patients with ES-SCLC were enrolled, of whom 70 (33.2%) patients received standard therapy plus TRT as first-line treatment, and 141 (66.8%) patients in the control group received PD-L1 inhibitors plus chemotherapy. After PSM, a total of 65 pairs of patients were enrolled in the analysis. There were no significant differences in baseline characteristics between the two groups of patients who received TRT and those who did not. In all patients, the median PFS (mPFS) in the TRT group and the non-TRT groupwere 9.5 months and 7.2 months, respectively, with HR = 0.60 (95% CI 0.41-0.87, p = 0.007). The median OS (mOS) in the TRT group was also significantly longer than that in the non-TRT group (24.1 months vs. 18.5 months, HR = 0.53, 95% CI 0.32-0.85, p = 0.009). Multivariable analysis showed that baseline liver metastasis and bone metastasis were independent prognostic factors for OS. In terms of safety, immunotherapy combined with thoracic radiotherapy increased the incidence of treatment-related pneumonia (p<0.001), most of which were grade 1-2.

CONCLUSION

This real-world study shows that adding TRT to durvalumab or atezolizumab plus chemotherapy significantly improves survival in ES-SCLC. It leads to more treatment-related pneumonia, but most of them can be relieved after symptomatic treatment. This treatment model deserves to be explored in prospective clinical trials.

[Clinical and pathological characteristics of immune-mediated liver injury caused by immune checkpoint inhibitors]

Objective: Cancer immunotherapy can lead to various side effects, termed immune-related adverse events (irAE). This study summarized and analyzed the clinical and pathological characteristics of immune-mediated liver injury caused by immune checkpoint inhibitors (ILICI). Methods: This is a retrospective case series study involving 11 patients diagnosed with ILICI at the Peking Union Medical College Hospital from November 2019 to November 2021. Patient demographic information and clinical data, including gender, age, ILICI onset, clinical and radiological manifestations, pathological features, treatment, and resumption of ICI were retrospectively collected and analyzed. Results: The patients were primarily males (9/11) with a median age of 65 (range: 32-73) years. ICI mainly resulted in either partial remission (4/11) or stable disease (3/11). ILICI occurred after a median of two cycles of anti-programmed cell death-1 (PD-1) therapy, with a median time from the initial and last anti-PD-1 therapy to ILICI onset of 57 days and 17 days, respectively. ILICI was mostly severe (3/11) or very severe (6/11). While the clinical and radiological manifestations were non-specific, the pathological features were active lobular hepatitis and portal inflammation, with prominent CD8⁺T lymphocyte infiltration. The basic treatment was hepatoprotective drugs (10/11). Glucocorticoids were used as the primary therapy (9/11) but were ineffective in 4 of 9 cases. Of these, 3 of 9 cases received combined treatment with mycophenolate mofetil (MMF), only one of whom achieved remission. By the end of the study, 2 of 11 cases had resumed ICI and neither had experienced an ILICI relapse. Conclusion: The ILICI patients in this study had a corresponding history of ICI treatment and pathological features. The main treatment included hepatoprotective drugs and glucocorticoids. Immunosuppressive drugs were added for some cases but had poor efficacy.

[Diagnostic value of different serological markers and correlation analysis with disease phenotype in inflammatory bowel disease]

Objective: To explore the diagnostic value of different serological markers and the correlation with disease phenotype in inflammatory bowel disease (IBD). Methods: The clinical data of 445 IBD patients in Peking Union Medical College Hospital from June 2010 to December 2020 were retrospectively collected, including 223 cases of ulcerative colitis (UC) [111 males, 112 females, with a median age of 46(20,79) years] and 222 cases of Crohn's disease (CD) [147 males, 75 females, with a median age of 39 (19, 72) years]. The positive rates of serum anti-neutrophil cytoplasmic antibodies (ANCA), anti-Saccharomyces cerevisiae antibodies (ASCA), goblet cell autoantibodies (GAB) and pancreatic autoantibodies (PAB) in the two groups were analyzed. The sensitivity, specificity, positive predictive value and negative predictive value of UC and CD were calculated. Logistic regression was performed to analyze the relationship between different combinations of antibodies and disease phenotype. Results: The positive rates of ASCA and PAB in CD patients were 34.7% (77/222) and 38.3% (85/222), respectively, which were higher than those in UC patients [10.3% (23/223) and 4.5% (10/223), P<0.001]. The positive rate of ANCA in UC patients was 50.2% (112/223), which was higher than that in CD patients [5.4% (12/222), P<0.001]. The positive rates of serum GAB in CD and UC patients were 21.6% (48/222) and 28.3% (63/223), respectively, with no significant difference (P=0.760). In patients with CD, the sensitivity of mono-marker ASCA (+), dual-marker ASCA (+) ANCA (-), quadruple-marker ASCA (+) ANCA (-) PAB (+) GAB (-) in diagnosing CD was 34.7%, 32.9%, 20.7%, the specificity was 89.7%, 95.5%, 100.0%, the positive predictive value was 77.0%, 90.1%, 100.0%, and the negative predictive value was 58.0%, 58.7%, 55.9%, respectively. In patients with UC, the sensitivity of mono-marker ANCA (+), dual-marker ANCA (+) ASCA (-), quadruple-marker ANCA (+) ASCA (-) PAB (-) GAB (+) in diagnosing UC was 50.2%, 40.4%, 24.2%, the specificity was 94.6%, 95.5%, 100.0%, the positive predictive value was 90.3%, 90.0%, 100.0%, and the negative predictive value was 65.4%, 61.4%, 56.8%, respectively. Mono-marker ASCA (+) (OR=3.39, 95%CI: 1.59-7.21), dual-marker ASCA (+) ANCA (-) (OR=2.87, 95%CI: 1.34-6.14), triple-marker ASCA (+) ANCA (-) GAB (-) (OR=3.09, 95%CI: 1.31-7.31) and quadruple-marker ASCA (+) ANCA (-) PAB (+) GAB (-) (OR=3.15, 95%CI: 1.56-8.03) were associated with stenosis and/or penetrating type CD. The mono-marker ANCA (+) (OR=2.69, 95%CI: 1.42-5.12) and dual-marker ANCA (+) ASCA (-) (OR=2.11, 95%CI: 1.03-4.16) were associated with extensive colonic lesions in UC. Conclusion: Based on ASCA or ANCA, the combination with PAB or GAB, is conducive to IBD diagnosis, and is associated with stenosis and/or penetrating type of CD and extensive type of UC.

[Risk factors and characteristics of gut microbiota and metabolites in inflammatory bowel diseases patients with urolithiasis]

Objective: To identify the related factors and characteristics of gut microbiota and metabolites in inflammatory bowel disease (IBD) patients with urolithiasis. Methods: A total of 68 IBD patients with urolithiasis and 136 gender-and age-matched IBD patients without urolithiasis in the Department of Gastroenterology, Peking Union Medical College Hospital from January 2014 to December 2019 were recruited. The diagnosis of urolithiasis was confirmed by plain films, ultrasonography, abdominal computed tomography or intravenous urography. The clinical data of patients were collected, and the association between the clinical characteristics and urolithiasis was further analyzed. The fecal samples were collected from 10 patients with urolithiasis and 18 patients without urolithiasis, and the gut microbiota and metabolites composition were analyzed. Results: There were 49 male and 19 female IBD patients with urolithiasis, with a mean age of (36.0±12.4) years, and 98 male and 38 female patients without urolithiasis, with a mean age of (36.1±12.5) years. Univariate analysis revealed that the rate of ileostomy and the resection of small intestine in Crohn's disease (CD) patients with urolithiasis (n=34) was significantly higher than CD patients without urolithiasis (n=68) (26.5% vs 7.4%, P=0.019). And the erythrocyte sedimentation rate was also higher [26.5 (12.0, 40.8) vs 13.0 (7.2, 32.5) mm/1 h, P=0.022] in CD patients with urolithiasis. There were no significant differences in clinical characteristics and biochemical parameters between the ulcerative colitis (UC) patients with urolithiasis (n=34) and without urolithiasis (n=68) (all P>0.05). The multivariate logistic regression analysis indicated that ileostomy and the resection of small intestine were the independent related factors for urolithiasis in CD patients (OR=4.619, 95%CI: 1.178-18.111, P=0.028). There was no significant difference in α and β diversity between the two groups (all P>0.05). At the phylum level, there was no significant difference in the abundance of microbiota (all P>0.05). At the genus level, the abundance of Enterococcus (P=0.049), Eubacterium_eligens (P=0.036) was significantly decreased. At the species level, the abundance of Bacteroides_coprocola was increased in urolithiasis group (P=0.035), while the abundance of Blautia_caecimuris was significantly decreased (P=0.042). No significant difference was found in fecal metabolites between the two groups (all P>0.05). According to LDA effect size (Lefse) analysis, taxa including Sphingomonadales, Fenollaria, Bacteroides_coprocola contributed greatly to the difference between the two groups. Conclusions: Ileostomy and the resection of small intestine are related factors for urolithiasis in patients with CD. Gut microbiota may be involved in the occurrence of urolithiasis in patients with IBD.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

Thrombotischer Verschluss der extrakorporalen Zirkulation während hepatischer Chemosaturation trotz zielgerechter Antikoagulation

Die perkutane hepatische Chemosaturation ist eine Behandlungsoption bei nichtresektablen primären oder sekundären Lebertumoren. Dabei wird der Bereich der Lebervenenmündung der Vena cava inferior (VCI) mittels 2 Ballons von der Zirkulation isoliert, sodass die systemische Verteilung des über die Leberarterie applizierten Chemotherapeutikums Melphalan verhindert wird. Nach Passage der Leber und venöser Drainage aus der retrohepatischen VCI durchläuft das chemosaturierte Blut 2 parallel geschaltete extrakorporale Filter. Anschließend wird das gereinigte Blut jugulär rückgeführt. Das Verfahren geht oft mit einer ausgeprägten hämodynamischen Instabilität einher, deren Ursache nicht abschließend geklärt ist. Zusätzlich stellt das Gerinnungsmanagement eine Herausforderung dar. Die Autoren berichten von einem Fall, bei dem sich trotz ausreichender „activated clotting time“ (ACT) ein Thrombus im rückführenden Schenkel der extrakorporalen Zirkulation bildete. Gezielte Problemsuche und -lösung waren parallel zur hämodynamischen Stabilisierung und interdisziplinären Zusammenarbeit notwendig, um die Intervention erfolgreich durchzuführen und der Patientin eine sichere Therapie zukommen zu lassen.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Genetic and epigenetic determinants of reactivation of Mecp2 and the inactive X chromosome in neural stem cells

Rett syndrome may be treated by reactivating the silent copy of Mecp2 from the inactive X chromosome in female cells. Most studies that model Mecp2 reactivation have used mouse fibroblasts rather than neural cells, which would be critical for phenotypic reversal, and rely on fluorescent reporters that lack adequate sensitivity. Here, we present a mouse model based on a dual bioluminescent and fluorescent reporter to assess the level of reactivation of Mecp2 and the inactive X chromosome by treating neural stem cells with 5-azacytidine and Xist knockdown. We show that reactivation of Mecp2 and other X-linked genes correlates with CpG density, with distance from escapees, and, very strongly, with the presence of short interspersed nuclear elements. In addition, X-linked genes reactivated in neural stem cells overlap substantially with early reactivating genes by induced pluripotent stem cell reprogramming of fibroblasts or neuronal progenitors, indicating that X chromosome reactivation follows similar paths regardless of the technique or cell type used.

193 ARE OLDER PATIENTS IN IRELAND BEING ADEQUATELY SCREENED FOR DELIRIUM? RESULTS FROM AN IRISH PERIPHERAL HOSPITAL

Background

Delirium is associated with increased morbidity and mortality in the older person and still remains poorly detected. The Health Service Executive (HSE) has clear algorithms and guidelines which suggest that any person over the age of 65, especially so for patients with pre-existing dementia, presenting to the Emergency Department (ED) or Acute Medical Assessment Unit (AMAU) should be screened for delirium using the 4AT test. An earlier retrospective audit carried out by the authors in the same hospital showed that only 9% of patients with diagnosed delirium had a 4AT test at any point during inpatient stay and 0% had one on admission. We designed a prospective audit to assess what proportion of patients over 65 coming through the Acute Medical Assessment Unit (AMAU) had a delirium screening test performed on admission.

Methods

We reviewed the admission notes of all patients over 65 admitted through the AMAU over a continuous 14 day period from 10/11/20 to 24/11/2020. The admission notes were reviewed within 24 hours of admission. Exclusion criteria included patients presenting delirium tremens and patients presenting with a stroke.

Results

119 patients were identified. The mean age was 78.1 years. 20 (16.8%) had previously diagnosed dementia. 0 patients had a delirium screening test conducted by AMAU/ED staff on admission. 2 (1.7%) had 4AT tests done by members of the Geriatric Emergency Medical Services (GEMS) team within 24 hours. The GEMS team only sees patients who fulfill certain criteria on admission. 10 (8.4%) had ‘delirium’ listed on their differential diagnoses.

Conclusion

Our results show that the older patient being admitted through the AMAU in this hospital in Ireland is not being adequately screened for delirium. Additionally, even when delirium was suspected, delirium screening tools were not being implemented for further assessment. More needs to be done to ensure patients over 65 are assessed as per guidelines.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

N95 respirator decontamination: a study in reusability

The coronavirus disease 2019 (COVID-19) pandemic had caused a severe depletion of the worldwide supply of N95 respirators. The development of methods to effectively decontaminate N95 respirators while maintaining their integrity is crucial for respirator regeneration and reuse. In this study, we systematically evaluated five respirator decontamination methods using vaporized hydrogen peroxide (VHP) or ultraviolet (254 nm wavelength, UVC) radiation. Through testing the bioburden, filtration, fluid resistance, and fit (shape) of the decontaminated respirators, we found that the decontamination methods using BioQuell VHP, custom VHP container, Steris VHP, and Sterrad VHP effectively inactivated Cardiovirus (3-log10 reduction) and bacteria (6-log10 reduction) without compromising the respirator integrity after 2-15 cycles. Hope UVC system was capable of inactivating Cardiovirus (3-log10 reduction) but exhibited relatively poorer bactericidal activity. These methods are capable of decontaminating 10-1000 respirators per batch with varied decontamination times (10-200 min). Our findings show that N95 respirators treated by the previously mentioned decontamination methods are safe and effective for reuse by industry, laboratories, and hospitals.

Combining tumor deposits with the number of lymph node metastases to improve the prognostic accuracy in stage III colon cancer: a post hoc analysis of the CALGB/SWOG 80702 phase III study (Alliance)☆

BACKGROUND

In colon cancer, tumor deposits (TD) are considered in assigning prognosis and staging only in the absence of lymph node metastasis (i.e. stage III pN1c tumors). We aimed to evaluate the prognostic value of the presence and the number of TD in patients with stage III, node-positive colon cancer.

PATIENTS AND METHODS

All participants from the CALGB/SWOG 80702 phase III trial were included in this post hoc analysis. Pathology reports were reviewed for the presence and the number of TD, lymphovascular and perineural invasion. Associations with disease-free survival (DFS) and overall survival (OS) were evaluated by multivariable Cox models adjusting for sex, treatment arm, T-stage, N-stage, lymphovascular invasion, perineural invasion and lymph node ratio.

RESULTS

Overall, 2028 patients were included with 524 (26%) TD-positive and 1504 (74%) TD-negative tumors. Of the TD-positive patients, 80 (15.4%) were node negative (i.e. pN1c), 239 (46.1%) were pN1a/b (<4 positive lymph nodes) and 200 (38.5%) were pN2 (≥4 positive lymph nodes). The presence of TD was associated with poorer DFS [adjusted hazard ratio (aHR) = 1.63, 95% CI 1.33-1.98] and OS (aHR = 1.59, 95% CI 1.24-2.04). The negative effect of TD was observed for both pN1a/b and pN2 groups. Among TD-positive patients, the number of TD had a linear negative effect on DFS and OS. Combining TD and the number of lymph node metastases, 104 of 1470 (7.1%) pN1 patients were re-staged as pN2, with worse outcomes than patients confirmed as pN1 (3-year DFS rate: 65.4% versus 80.5%, P = 0.0003; 5-year OS rate: 87.9% versus 69.1%, P = <0.0001). DFS was not different between patients re-staged as pN2 and those initially staged as pN2 (3-year DFS rate: 65.4% versus 62.3%, P = 0.4895).

CONCLUSION

Combining the number of TD and the number of lymph node metastases improved the prognostication accuracy of tumor-node-metastasis (TNM) staging.

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

[Clinical characteristics and microbiome analysis in patients with anti-programmed cell death protein 1 related colitis]

Objective: To analyze clinical characteristics and monitor microbiome changes in patients with anti-PD-1 associated colitis. Methods: Two patients with non-small cell lung cancer who developed colitis after treated with anti-PD-1 antibodies were retrospectively analyzed in Peking Union Medical College Hospital from January 2019 to January 2020. The clinical symptoms, endoscopic and pathological manifestations, as well microbiome changes were analyzed and compared during pre-treatment, post-treatment and relapse. Results: The main clinical manifestations included diarrhea, elevated inflammatory indicators, colonic mucosal diffuse hyperemic edema with erosion by endoscopy. Changes in the structure of crypts were common pathological characteristics. Glucocorticoids were effective agents, which achieved clinical remission and mucosal healing. The microbiome composition of OTUs was different. After glucocorticoid treatment, the alpha diversity Observed species, Shannon, Simpson, Chao1, ACE indexes all decreased. The Firmicutes decreased with Bacteroidetes increasing in phylum level; while the Bacteroides increased with Ruminococcaceae decreasing in genus level. Lactobacillus was the potentially beneficial genus. Conclusion: Patients developing anti-PD-1 associated colitis have characteristic clinical and pathological manifestations. Glucocorticoids are effective treatment. The fecal microbiome diversity, relative abundance of major phylum and genus have changed after treatment.

[Protective effect and mechanism of Lactobacillus rhamnosus on immune checkpoint inhibitors related colitis in mice]

Objective: Modeling the immune-related adverse events (irAE) colitis in mice, and explore the protective effect and related mechanism of Lactobacillus rhamnosus GG (LGG) on irAE colitis. Methods: C57BL/6 mice were divided into dextran sodium sulfate (DSS) group (n=3), DSS+anti-programmed death receptor 1 (PD-1) group (n=4), DSS+anti-PD-1+anti-cytotoxic T lymphocyte associated protein 4 (CTLA-4) Group (n=4), DSS+anti-PD-1+anti-CTLA-4+LGG group (n=4), all were given corresponding drugs and probiotics intervention. The severity of colitis were assessed by weight loss, disease activity index (DAI), colon length, colon histopathological score. The inflammatory cytokines and T cell immunity of CD4⁺, CD8⁺, FoxP3⁺regulatory T cells (Treg), were detected by real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemical staining respectively. Results: Compared to DSS group, the Day 9 weight [(87.40±1.79)% vs (94.57±0.53)%, P<0.05], colon length [(5.33±0.27)cm vs (6.63±0.12)cm, P<0.05] were lower, and DAI score(2.66±0.24 vs 0.89±0.48), colon histopathological score (12.50±1.04 vs 5.67±0.33), tumor necrosis factor-α (TNF-α) (6.73±1.68 vs 0.91±0.40) (P<0.05), as well CD8⁺T cells (156.80±8.84 vs 89.00±6.66) and FoxP3⁺Treg cells (103.80±2.66 vs 48.33±3.18) (P<0.05) were higher in DSS+anti-PD-1+anti-CTLA-4 group. Compared to DSS+anti-PD-1+anti-CTLA-4 group, the DAI score(1.83±0.17 vs 2.66±0.24), colonic histopathology score (8.75±0.63 vs 12.50±1.04), TNF-α level (1.32±0.18 vs 6.73±1.68) (P<0.05) were lower; and CD8⁺T cells(97.75±3.75 vs 156.80±8.84, P<0.01) level was lower with higher FoxP3⁺Treg cells (126.00±8.33 vs 103.80±2.66, P=0.046) in DSS+anti-PD-1+anti-CTLA-4+LGG group. Conclusion: DSS combined with anti-PD-1 and anti-CTLA-4 can successfully modeling the irAE colitis in mice, LGG can reduce irAE colitis severity by regulating Treg cells.

Diagnostic value of the combined detection of CEA, NSE and IL-18 for lung cancer and their relationship with apoptosis gene Bcl-2

This study aims to investigate the value of the combined detection of carcinoembryonic antigen (CEA), Neuron-specific enolase (NSE) and the level of Interleukin-18 (IL-18) in the serum in the diagnosis of lung cancer. The correlation between these parameters and the expression levels of B-cell lymphoma-2 (Bcl-2) protein were also studied. Eighty patients with lung cancer were included in the lung cancer group. These patients underwent surgery in the Department of Oncology of Huai'an Second People's Hospital between February 2016 and February 2018. During the same period, another 80 patients with benign lung lesions were registered in the benign lesion group and 80 healthy people were enrolled in the control group. Enzyme-linked immunosorbent assay (ELISA) was used to detect the expression levels of CEA, NSE and IL-18. The diagnostic critical value of these factors was used as positive indicator. When CEA, NSE and IL-18 levels were positive at the same time, the combined detection was considered to be positive. WB was used to detect Bcl-2 expression level. We also analyzed the possible correlation between CEA, NSE, IL-18 levels and the Bcl-2 expression levels. The CEA, NSE and IL-18 expression levels in the serum of the lung cancer group were significantly higher than those in the benign lesion and the control groups (p<0.05). The area under ROC curve for CEA, NSE and IL-18 respectively was 0.770 (0.697-0.843), 0.829 (0.767-0.890), 0.721 (0.642-0.800) (p<0.001). IL-18 level was negatively correlated with the level of Bcl-2 mRNA in the tissue (r=-0.380, p<0.001). In conclusion, CEA, NSE and IL-18 have a good auxiliary diagnostic value in patients with lung cancer. The combined detection could improve the sensitivity and specificity of lung can¬cer diagnosis. There was a negative correlation between IL-18 and Bcl-2 levels which suggested a potential inhibitory role of IL-18 on the lung cancer cells apoptosis pathway.

Progress and current status of molecule-targeted therapy and drug resistance in gastric cancer

Gastric cancer is one of the most common malignant tumors in the world. In China, its morbidity and mortality are second only to lung cancer. Chemotherapy combined with targeted therapy brings survival benefits to patients with advanced gastric cancer. Targets for targeted therapy of gastric cancer include human epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), vascular endothelial growth factor (VEGF), mammalian target of rapamycin (mTOR) and Claudin 18.2 (CLDN 18.2). The main challenge of tumor molecule-targeted drugs is resistance. The main mechanisms of drug resistance include tumor establishment of compensatory signaling pathways, target protein changes, tumor microenvironment changes, tumor heterogeneity and tumor adaptation to targeted drugs. The combined action of multiple drug resistance mechanisms promotes the development of targeted drug resistance. In order to attract the attention of researchers, this paper reviews the mechanisms of drug resistance in gastric cancer-targeted therapy. In addition, the research status of drug resistance in molecule-targeted therapy of gastric cancer is summarized. It is of great clinical significance to explore the drug resistance mechanisms of targeted drugs and reverse drug resistance in gastric cancer. Last, the future development of molecule-targeted therapy is prospected.

Silencing of TPD52 inhibits proliferation, migration, invasion but induces apoptosis of pancreatic cancer cells by deactivating Akt pathway

Pancreatic cancer (PC) is a complex and multifactorial human malignancy with a low survival rate. Tumor protein D52 (TPD52) was abnormally expressed in several cancers and participated in tumorigenesis. However, the oncogenic effect of TPD52 on PC remains unknown. In the present study, after transfecting AsPC-1 and PANC-1 cells with NC or sh-TPD52, the CCK-8 assay, Hoechst staining, western blot, transwell assay, flow cytometry were used to examine the cell proliferation, migration, invasion and apoptosis. qRT-PCR results confirmed that the expression of TPD52 was significantly increased in PC cells, especially AsPC-1 and PANC-1 cells. The present study revealed that silencing of TPD52 significantly suppressed the proliferation, migration and invasion, but induced apoptosis of AsPC-1 and PANC-1 cells in vitro by dephosphorylating Akt at Ser473. Conversely, SC79, an Akt activator, could partially reverse the anti-metastatic effects of sh-TPD52, accompanied by the reactivating of Akt pathway. Additional in vivo studies are warranted to elucidate that knockdown of TPD52 could inhibit tumor growth in PC mice models. These findings suggested that TPD52 might be a novel therapeutic target for PC treatment.

Relationship between extralaryngeal endoscopic findings, proton pump inhibitor (PPI) response, and pH measures in suspected laryngopharyngeal reflux

Laryngopharyngeal reflux (LPR) is a clinical entity diagnosed by history laryngoscopic findings that has a variable response to empiric proton-pump inhibitor (PPI) therapy. While the reflux finding score (RFS), an endoscopic scoring scheme, has been advanced as a measure of LPR, it has not been externally validated against symptom severity in practice. Extralaryngeal pharyngeal endoscopic findings may have diagnostic utility but remain underexplored. This study assesses the correlation between extralaryngeal findings and (1) 24-hour oropharyngeal pH & (2) PPI response in patients with suspected LPR. Subjects presented to a tertiary care center with laryngeal symptoms ≥1 month and reflux symptom index (RSI) ≥13. Following baseline questionnaires, laryngoscopy, and a 24-hour oropharyngeal pH probe study, subjects were prescribed 8-12 week omeprazole trials. Baseline endoscopic findings were scored in a blinded fashion using the RFS and extralaryngeal score criteria, summatively the 'ELS.' PPI response was defined as ≥50% improvement in RSI. Thirty-three subjects with flexible endoscopic recordings completed baseline and follow-up questionnaires. The cohort's baseline mean RSI was 23.0 ± 7.2 with a ΔRSI = 9.8 after PPI therapy. The baseline RFS score averaged 5.3 ± 2.7. 45% of our subjects was found to be PPI responsive. The Cohen's kappa for the ELS but not the RFS was significant. There were no significant differences between the RFS (P = 0.10) or ELS (P = 0.07) for PPI responders & nonresponders. Oropharyngeal pH measures did not correlate with the RFS or ELS. In conclusion, endoscopic scores of laryngeal and extralaryngeal findings did not predict PPI response or oropharyngeal acid exposure in suspected LPR.

Abstract P6-17-39: BAT8001, a potent anti-HER2 antibody-drug conjugate with a novel stable linker for the treatment of HER2-positive breast cancer

Overexpression of HER2 occurs in approximately 20% of breast cancers and is associated with shortened survival. Trastuzumab emtansine (T-DM1), an anti-HER2 ADC, has shown efficacy in HER2-positive breast cancer patients and was approved by the FDA and EMA for advanced HER2-positive breast cancer. However T-DM1 causes grade 3 and 4 thrombocytopenia in up to 14.5% of patients as its major toxicity. The thrombocytopenia is likely caused by one of T-DM1's catabolites and payload, DM1, indicating T-DM1's linker can be cleaved. Here we adopted a novel noncleavable linker and created an anti-HER2 ADC, BAT8001, which is expected be efficacious in HER2-positive breast cancer and have a better side effect profile relative to T-DM1 due to the stability of BAT8001's noncleavable linker. BAT8001 is internalized in HER2-positive cancer cells. It inhibits proliferation of HER2-positive tumor cells with IC50s of ˜0.1 nM, similar to the potency of T-DM1. BAT8001 also induces apoptosis in HER2-positive cancer cells. In both cell-line and patient-derived mouse xenograft (PDX) models, BAT8001 demonstrates strong inhibition activity on tumor growth. For example, in a cell-line model of breast cancer (BT474), BAT8001 demonstrates potent activity with complete responses in all animals tested at the 15mg/kg dose level. Pharmacokinetics studies in monkey reveals BAT8001 has similar Cmax, AUC, and t1/2 as T-DM1. The major catabolite of BAT8001 is the Cys-linker-payload containing product. No free payload is observed. This compares favorably with T-DM1 where free DM1, T-DM1's payload, is one of the major catabolites. In a multiple dose toxicity study, BAT8001 had a NOAEL of 15 mg/kg versus 10 mg/kg for T-DM1. BAT8001 exhibits similar potency to T-DM1 on inhibiting HER2-positive cell proliferation and tumor growth, yet demonstrates better multiple dose toxicity than T-DM1. The improved toxicity profile of BAT8001 suggests that the novel noncleavable linker utilized in BAT8001 is more stable than the linker utilized in T-DM1. BAT8001 is very efficacious in cell-line xenograft models of breast cancer. The preclinical profile of BAT8001 warrants further development for the treatment of breast cancer and other HER2-positive cancers.

Citation Format: Tang W, Deng X, Ou Z, Gan J, Dong Q, Tan B, Lu L, Chen B, Bao C, Li S, Thomas B, Yu J-C. BAT8001, a potent anti-HER2 antibody-drug conjugate with a novel stable linker for the treatment of HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-39.

Contemporary global perspectives of medical students on research during undergraduate medical education: a systematic literature review

BACKGROUND

The need for increased expertise in evidence-based medicine and concerns about the decreasing numbers of physician-scientists have underscored the need for promoting and encouraging research in medical education. The critical shortage of physician-scientists has assumed a dimension demanding a coordinated global response. This systematic review examined the perceptions of medical students regarding research during undergraduate medical school from a global perspective.

METHODS

Articles for this review were searched using PubMed, SCOPUS and Cochrane. Studies published within the last 10 years of the start date of the study that met specified criteria were included. Identified articles were initially screened by title as well as keywords and their abstracts were further screened to determine relevance. Full-text of screened articles were read for validation prior to inclusion.

RESULTS

A total of 26 articles from the literature met the set criteria for final inclusion. Contents of the abstracts and corresponding full-text articles were analyzed for themes on the research perspectives of medical students. The themes derived comprised: research interest, physician-scientist decline and shortage, responses to physician-scientist shortage, curriculum issues, skills (motivation and self-efficacy), research needs, socioeconomic and cultural issues, and barriers.

CONCLUSION

Despite the wide variations in medical education systems worldwide, the perspectives of medical students on research in undergraduate medical education shared many common themes. Globally, medical students underscored the necessity and importance of research in medical education as reflected by many students reporting positive attitudes and interest in research endeavors. Moreover, a worldwide consensus emerged regarding the decline in the numbers of physician-scientists and the necessity for a reversal of that trend. Various barriers to research engagement and participation were highlighted.

Adherence to Continuous Positive Airway Pressure therapy in Singaporean patients with Obstructive Sleep Apnea

PURPOSE

To investigate the rates of Continuous Positive Airway Pressure (CPAP) uptake and adherence amongst Singaporean patients diagnosed with Obstructive Sleep Apnea (OSA), and to evaluate factors correlated with CPAP uptake and adherence.

STUDY DESIGN

Retrospective review of medical records.

METHODS

Medical records were reviewed for baseline demographics, daytime sleepiness, presence of nasal symptoms and OSA severity, initial treatment choice, the rate of CPAP treatment uptake and CPAP adherence at 1 and 12 months.

RESULTS

2160 patients were diagnosed with OSA within the 5-year period (2011-2015). 463 (21.4%) had mild OSA, 583 (27.0%) had moderate OSA and 1114 (51.6%) had severe OSA. For initial therapy, 751 (34.8%) patients opted for a 1-month CPAP trial, 288 (13.3%) patients chose surgery upfront, 291 (13.5%) patients chose adjunctive treatments (weight loss, positional therapy, dental appliance, intranasal steroid spray for allergic rhinitis) and 830 (38.4%) patients rejected all forms of treatment. 337 out of 751 patients (44.9%) were adherent to CPAP therapy during the 1 month trial. 381 out of 751 (50.7%) patients took up CPAP therapy following the trial period, of which 299 out of 381 (78.5%) patients were adherent to CPAP therapy at 1 year. CPAP adherence during the 1-month trial was a predictor for eventual CPAP treatment uptake and CPAP adherence at 1 year (p < 0.001). Age (p < 0.001), BMI (p < 0.001) and normal ESS (p = 0.01) were predictors of treatment rejection. 24 patients underwent upper airway surgery during their first year of using CPAP. 21 out of the 24 patients (87.5%) were adherent to CPAP at 1 year after undergoing surgery. These patients had a higher rate of CPAP adherence compared to the overall cohort (87.5% versus 78.5%), but this was not statistically significant (p > 0.05).

CONCLUSION

Singaporean patients who accept CPAP therapy after an initial 1-month CPAP trial will generally be adherent to CPAP therapy. Initial patterns of CPAP usage are predictive of long term CPAP adherence. However, there is a high rate of CPAP treatment rejection both at the time of diagnosis and after the CPAP trial. Upper airway surgery in selected patients may improve CPAP adherence.