Combined immune checkpoint inhibition with durvalumab and tremelimumab with and without radiofrequency ablation in patients with advanced biliary tract carcinoma

BACKGROUND

Current standard of care for advanced biliary tract cancer (BTC) is gemcitabine, cisplatin plus anti-PD1/PD-L1, but response rates are modest. The purpose of this study was to explore the efficacy and safety of durvalumab (anti-PD-L1) and tremelimumab (anti-CTLA-4), with and without an interventional radiology (IR) procedure in advanced BTC.

METHODS

Eligible patients with advanced BTC who had received or refused at least one prior line of systemic therapy were treated with tremelimumab and durvalumab for four combined doses followed by monthly durvalumab alone with and without an IR procedure until the progression of disease or unacceptable toxicity. Objective response was assessed through CT or MRI by Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1) every 8 weeks. Adverse events (AEs) were recorded and managed. The primary endpoint was 6-month progression-free survival (PFS).

RESULTS

Twenty-three patients with advanced BTC were enrolled; 17 patients were assigned to treatment with durvalumab and tremelimumab (Durva/Treme); and 6 patients were treated with the combination of durvalumab, tremelimumab plus IR procedure (Durva/Treme + IR). The best clinical responses in the Durva/Treme arm were partial response (n = 1), stable disease (n = 5), progressive disease (n = 5), and in the Durva/Treme + IR arm: partial response (n = 0), stable disease (n = 3), progressive disease (n = 3). The median PFS was 2.2 months (95% CI: 1.3-3.1 months) in the Durva/Treme arm and 2.9 months (95% CI: 1.9-4.7 months) in the Durva/Treme + IR arm (p = 0.27). The median OS was 5.1 months (95% CI: 2.5-6.9 months) in the Durva/Treme arm and 5.8 months (95% CI: 2.9-40.1 months) in the Durva/Treme + IR arm (p = 0.31). The majority of AEs were grades 1-2.

CONCLUSION

Durva/Treme and Durva/Treme + IR showed similar efficacy. With a manageable safety profile. Larger studies are needed to fully characterize the efficacy of Durva/Treme ± IR in advanced BTC.

A156 OUTCOMES FOLLOWING ENDOSCOPIC RESECTION OF GASTRIC NEUROENDOCRINE TUMOURS FROM A TERTIARY-CARE ACADEMIC CENTRE

Background

Gastric neuroendocrine tumours (G-NET) are rare cancers derived from neuroendocrine cells of the stomach. A steady increase in the incidence of these tumours has been observed. Current treatment and surveillance strategies are guided by various tumour characteristics including size, grade, and depth of invasion. There exists conflicting evidence, however, on the rates of recurrence from positive resection margins following primary endoscopic resection. Thus, it remains uncertain whether complete endoscopic resection (R0) of these indolent tumours is clinically significant and whether follow-up endoscopic or surgical intervention is justified.

Purpose

Our aim is to characterize current management patterns and clinical outcomes in patients undergoing endoscopic resection of G-NETs.

Method

We conducted a retrospective, single-centre cohort study at The Centre for Advanced Therapeutic Endoscopy and Endoscopic Oncology at St. Michael’s Hospital, Toronto, Ontario. Consecutive patients over the age of 18 who underwent endoscopic resection of histologically proven G-NETs between 2011 and 2020 were included. Data on patient, endoscopic, and tumour characteristics were collected through electronic chart review. Descriptive statistics were conducted for data analysis.

Result(s)

A total of 155 foregut neuroendocrine tumours were endoscopically resected during the study period, of which 108 were identified as G-NETs. 95.3% were classified as Type I. Mean tumour size was 8.93 ± 5.27 mm. Cap-assisted EMR was performed most frequently (n=51), followed by conventional EMR (n=35). ESD was performed in eight cases. Seven intra-procedural perforations occurred, of which all were closed endoscopically. One patient experienced post-procedural perforation requiring ICU and surgery. Positive resection margins (R1) were found in 25% of cases (n=27), of which 78% were assessed at surveillance endoscopy 1 (SE1). Six patients with R1 margins were referred for surgical evaluation and four were lost to follow-up. 78% of all resected G-NETs were followed at SE1 with a median interval of 196 days (range, 23 to 3373). SE1 recurrence rate at the primary resection site was 14% (n=12), of which two were from routine scar biopsies in the absence of endoscopically identifiable recurrence. All visible recurrences at these sites (n=10) were managed with repeat endoscopic resection. Patient and tumour characteristics in the evaluation of G-NET recurrence are presented in Table I.

Image

Conclusion(s)

G-NET recurrence occurs in less than 15% of patients at surveillance endoscopy following endoscopic resection in spite of a predictably higher R1 resection rate. Patient, endoscopic, and tumour factors including method of resection and margin status do not appear to impact the development of early recurrence. Given the indolent nature of these tumours, patients with positive resection margins can be followed conservatively. Further investigation is warranted to determine the optimal duration and surveillance strategy for these patients.

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None

Disclosure of Interest

None Declared

A155 OUTCOMES FOLLOWING ENDOSCOPIC RESECTION OF DUODENAL NEUROENDOCRINE TUMOURS FROM A TERTIARY-CARE ACADEMIC CENTRE

Background

Duodenal neuroendocrine tumours (D-NET) are rare cancers derived from neuroendocrine cells of the duodenum. A steady increase in the incidence of these tumours has been observed. Current treatment and surveillance strategies are guided by various tumour characteristics including size, grade, and depth of invasion. There exists conflicting evidence, however, on the rates of recurrence after positive resection margins following endoscopic resection. Thus, it remains uncertain whether complete endoscopic resection (R0) of these indolent tumours is clinically significant and whether follow-up endoscopic or surgical intervention is justified.

Purpose

Our aim is to characterize endoscopic management and clinical outcomes in patients undergoing endoscopic resection of D-NETs.

Method

We conducted a retrospective, single-centre cohort study at The Centre for Advanced Therapeutic Endoscopy and Endoscopic Oncology at St. Michael’s Hospital, Toronto, Ontario. Consecutive patients over the age of 18 who underwent endoscopic resection of histologically proven D-NETs between 2011 and 2020 were included. Data on patient, endoscopic, and tumour characteristics were collected through electronic chart review. Descriptive statistics were conducted for data analysis.

Result(s)

A total of 155 foregut neuroendocrine tumours (NET) were endoscopically resected amongst 96 patients during the study period. 47 of these were histologically identified as D-NETs. Mean tumour size was 9.88 ± 6.86 mm. Conventional endoscopic mucosal resection (EMR) was performed most frequently (55%, n=26/47), followed by cap-assisted EMR (30%, n=14/47). Hybrid endoscopic submucosal dissection (ESD)/EMR was performed in one case. A total of two intra-procedural perforations occurred, both of which were successfully closed endoscopically. One patient with a peri-ampullary D-NET experienced significant intra-procedural bleeding requiring Hemospray® and subsequent endotracheal intubation resulting in a brief hospitalization. 57% of all resected D-NETs were followed at surveillance endoscopy 1 (SE1) at a median interval of 199 days (range, 84 to 830). Positive resection margins (R1) were found in 26 cases (55%), of which 16 were assessed at SE1 while nine were lost to follow-up. One patient with R1 margins was electively treated with APC at SE1. Tumour recurrence at SE1 occurred in only two patients.

Image

Conclusion(s)

D-NET recurrence is found in less than 5% of patients at surveillance endoscopy following endoscopic resection in spite of a high R1 resection rate. Given this indolent nature of these tumours, our study suggests that patients with positive resection margins can be followed conservatively with surveillance endoscopy. Further investigation is warranted to determine the optimal duration and surveillance strategy for these patients.

Please acknowledge all funding agencies by checking the applicable boxes below

CAG

Disclosure of Interest

None Declared

Verteporfin synergizes the efficacy of anti-PD-1 in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is one of the primary hepatobiliary malignant neoplasms with only 10% of 5-year survival rate. Promising immunotherapy with the blockade of immune checkpoints has no clear benefit in CCA. The inhibition of YAP1 signaling by verteporfin has shown encouraging results by inhibiting cell proliferation and inducing apoptosis. This study aimed to evaluate the potential benefit of the combination of verteporfin and anti-programmed cell death 1 (PD-1) in CCA mouse model.

METHODS

We assessed the cytotoxicity of verteporfin in human CCA cell lines in vitro, including both intrahepatic CCA and extrahepatic CCA cells. We examined the in vitro effect of verteporfin on cell proliferation, apoptosis, and stemness. We evaluated the in vivo efficacy of verteporfin, anti-PD-1, and a combination of both in subcutaneous CCA mouse model.

RESULTS

Our study showed that verteporfin reduced tumor cell growth and enhanced apoptosis of human CCA tumor cells in vitro in a dose-dependent fashion. Nevertheless, verteporfin impaired stemness evidenced by reduced spheroid formation and colony formation, decreased numbers of cells with aldehyde dehydrogenase activity and positive cancer stem cell markers (all P < 0.05). The combination of verteporfin and anti-PD-1 reduced tumor burden in CCA subcutaneous SB1 tumor model compared to either agent alone.

CONCLUSIONS

Verteporfin exhibits antitumor effects in both intrahepatic and extrahepatic CCA cell lines and the combination with anti-PD-1 inhibited tumor growth.

222 Robotic Surgery: Public Perceptions and Current Misconceptions

Aim

While surgeons and robotic companies are key stakeholders involved in the adoption of Robotic Surgery (RS), the public's role is often overlooked. However, given that patients hold ultimate power over their healthcare decisions, public acceptance of RS is crucial. This study aims to identify public understanding, opinions and misconceptions on RS and present solutions to facilitate its wider integration.

Method

An online questionnaire distributed via social media platforms between February and May 2021 identified the views of UK adults on RS. The data was evaluated using thematic analysis, descriptive statistics, and statistical analysis. Statistical differences in age, gender, education level, and presence in the medical field were also sought.

Results

263 responses were obtained, with 216 (82.1%) analysed. Demographic differences provided significantly different results. Participants were relatively uninformed about RS, with a median knowledge score of 4.00(2.00–6.00) on a 10-point likert scale. Fears surrounding increased risk, reduced precision and technological failure were identified, alongside misconceptions on what RS entails, including it being autonomous. However, providing factual information in the survey about RS statistically increased participant comfort (p=&lt;0.0001). Most (61.8%) participants believed robot manufacturers were responsible for malfunctions, but doctors were held accountable more by older, less educated, and non-medical participants.

Conclusions

This study highlights the role of negative and inaccurate public perceptions surrounding RS in impeding its widespread adoption. Greater emphasis must be placed on patient education in RS to mitigate misconceptions and ensure greater diffusion of its benefits

219 The Opportunities and Challenges of Robotic Surgery: A Surgeon and Robotic Company Perspective

Introduction

As an increasing number of specialties have begun to adopt robotic surgery (RS), its prevalence within the NHS is continually rising. This study aims to establish stakeholders’ opinions on the opportunities and challenges of the widespread adoption of RS.

Method

Participants were recruited through social media platforms such as LinkedIn or via university affiliations and current RS research. Semi-structured interviews of eight surgeons and five company representatives were conducted online. Transcripts were analysed to formulate themes surrounding the opportunities and challenges of RS.

Results

This study identified six common themes amongst shareholders: Perspective, Ethics, Impact of Robotics, Training, Adoption and Finances. The success rates and quality of results offered by RS make it a recognised future surgical staple amongst interviewees. However, the technology remains a contentious subject amongst surgeons, with many doubting whether the benefits outweigh the costs associated with implementation. Such reservations are further exacerbated by the absence of a formal training pathway. National guidelines are necessary to embed RS within the NHS infrastructure, allowing greater standardisation for patients and surgeons. The importance of patient education to address misconceptions was emphasised. Despite current high costs, robotic technology is forecasted to become cheaper with greater use and increased market competition. Interviewees stressed that responsibility for errors lies with the surgeon, but with the manufacturer for instrument malfunctions.

Conclusions

This study highlights stakeholders’ views on the opportunities and challenges of RS. The identified themes should form the basis of the proposed recommendations to facilitate a more widespread adoption of RS.

Redefining Intermediate-Stage HCC Treatment in the Era of Immune Therapies

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. At diagnosis, most patients are ineligible for curative surgery, and approximately 20% of patients are diagnosed with advanced-stage disease. A significant proportion of patients fall under an unresectable or intermediate-stage disease who have liver-limited disease but are not surgical candidates because of large tumor size, number of lesions, or technically inoperable disease. In this unique intermediate-stage patient population, locoregional therapies have been the de facto mainstay of treatment because of high local response rates and favorable safety profile, especially in the context of minimally effective systemic therapies. However, not all patients who receive locoregional therapy for incurable disease have improved survival, and importantly, some of these patients never receive systemic therapy because of disease progression or further decline in hepatic function. Meanwhile, with the remarkable progress that has been made with systemic therapy in the past few years, revisiting the treatment of intermediate-stage HCC seems prudent. In this review, we will highlight current and emerging strategies for treating patients with unresectable, liver-limited HCC.

Favorable response to second-line atezolizumab and bevacizumab following progression on nivolumab in advanced hepatocellular carcinoma: A case report demonstrating that anti-VEGF therapy overcomes resistance to checkpoint inhibition

RATIONALE

Advanced hepatocellular carcinoma (HCC) remains a deadly disease in part due to decades of limited therapeutic options. With recent advances in our understanding of the tumor biology, several promising treatment strategies involving targeted and immunotherapies have emerged. However, enhancing their modest efficacy in HCC and other gastrointestinal malignancies is essential to improving survival.

PATIENT CONCERNS

A man in his late 50s with a history of type 2 diabetes mellitus and morbid obesity initially presented with progressive abdominal pain and anorexia prompting an abdominal computed tomography scan that revealed a large solitary liver mass with extensive local involvement.

DIAGNOSES

Although there were features consistent with a primary gastric tumor on subsequent endoscopic evaluation leading to early diagnostic uncertainty, his clinical picture, including a dominant liver mass, immunohistochemical staining profile, and significantly elevated alpha fetoprotein ultimately favored HCC.

INTERVENTIONS

The patient received palliative systemic therapy with infusional fluorouracil for a presumed gastric primary, however restaging scans after 3 cycles demonstrated disease progression. The consensus from a multidisciplinary discussion was that his pathology was more consistent with primary HCC. He was subsequently started on nivolumab with a partial response, although after 5 months, he progressed prompting initiation of second-line atezolizumab and bevacizumab with a favorable response.

OUTCOMES

The addition of atezolizumab and bevacizumab led to a sustained biochemical and radiographic response that appeared to overcome the resistance to nivolumab monotherapy. Aside from several mild immune-related adverse effects, his quality of life has greatly improved and he has tolerated treatment well to date.

LESSONS

Our findings suggest that vascular endothelial growth factor inhibition can overcome resistance to checkpoint inhibition in advanced HCC by resulting in a unique synergy that has never before been described in patients. The biological rationale for this response is likely attributable to the immunomodulatory effects of antiangiogenic agents, promoting an immunostimulatory microenvironment that can be exploited by immune checkpoint inhibitors for more effective antitumor activity. Given the considerable benefit patients may derive following progression on first-line treatment, it is important to consider this strategic combination of therapies which can ultimately lead to improved patient outcomes.

Multicenter, randomized phase II study of neoadjuvant pembrolizumab plus chemotherapy and chemoradiotherapy in esophageal adenocarcinoma (EAC)

4005

Background: Recent transformative studies in the treatment of EAC support adjuvant nivolumab for patients with residual disease following neoadjuvant chemoradiotherapy (CRT) (Checkmate 577) and pembrolizumab (P) with chemotherapy in untreated metastatic disease (Keynote 590). We hypothesized that pre-operative P combined with CRT can further improve outcomes in patients with locally advanced EAC. Methods: Patients with cT3-4Nx or T2N1 M0 EAC or gastroesophageal junction (GEJ) adenocarcinoma eligible for curative surgery were randomized (1:1) to receive either full-dose paclitaxel (T)/ carboplatin (C) or T/C + P induction therapy. All patients then received CRT with weekly T/C, RT 41.4Gy in 23 fractions, and P every 3 weeks. Following resection, patients received P for one year. The primary endpoint is rate of major pathologic response (MPR), defined as pathologic complete response or near complete response ( < 10% residual cancer), with 80% power and 0.1 one-sided significance level to detect the difference between a MPR proportion of 30% (historical control) and an alternative hypothesis of 47% (with preoperative P). Tissue was collected for tumor immune microenvironment (TIME) analysis including bulk and single cell RNA(scRNA) expression analysis, DNA sequencing, and flow cytometry. Results: From 8/4/17 to 10/26/20, 40 patients were enrolled: median age 68 [38-81], male 32, esophagus/GEJ type I (n = 16), GEJ II/III (n = 24). CRT was well tolerated, with no grade 3-4 adverse events attributed to P. Notable toxicity included grade 3-4 pneumonitis (13%), anastomotic leak (13%), infection (35%). In 31 evaluable patients to date, the MPR rate was 50.0% (95% CI, 32.7%-67.3%). 1-yr disease free survival was 100% for patients with MPR vs. 31.8% without MPR, p = 0.002. Esophageal/GEJ type I cancers had a significantly higher MPR rate when compared with GEJ type II/III (76.9% vs 37.5%, p = 0.03). scRNA seq on > 100,000 tumor cells revealed EAC/GEJ type I had higher infiltration of activated dendritic cells (p = 0.12), whereas GEJ tumors have significantly higher infiltration of activated B cells (p = 0.02). Conclusions: The addition of P to preoperative CRT for EAC is safe and associated with a significantly higher MPR rate compared to historical data. We found MPR to be significantly enriched in EAC/GEJ type I tumors compared with GEJ II/III, associated with important differences in the baseline tumor immune microenvironment. Clinical trial information: NCT02998268.

Immune Checkpoint Inhibitor Associated Hepatotoxicity in Primary Liver Cancer Versus Other Cancers: A Systematic Review and Meta-Analysis

BACKGROUND

Overall risks of hepatotoxicity with immune checkpoint inhibitors (ICIs) have yet to be compared in primary liver cancers to other solid tumors.

METHODS

We reviewed data from the PubMed, Embase, and Scopus databases, and assessed the risk of hepatotoxicity associated with ICIs.

RESULTS

A total of 117 trials were eligible for the meta-analysis, including 7 trials with primary liver cancers. The most common hepatotoxicity was ALT elevation (incidence of all grade 5.29%, 95% CI 4.52-6.20) and AST elevation (incidence of all grade 5.88%, 95% CI 4.96-6.97). The incidence of all grade ALT and AST elevation was 6.01% and 6.84% for anti-PD-1 (95% CI 5.04-7.18/5.69-8.25) and 3.60% and 3.72% for anti-PD-L1 (95% CI 2.72-4.76/2.82-4.94; p< 0.001/p<0.001). The incidence of ≥ grade 3 ALT and AST elevation was 1.54% and 1.48% for anti-PD-1 (95% CI 1.19-1.58/1.07-2.04) and 1.03% and 1.08% for anti-PD-L1 (95% CI 0.71-1.51/0.80-1.45; p= 0.002/p<0.001). The incidence of all grade ALT and AST elevation was 13.3% and 14.2% in primary liver cancers (95% CI 11.1-16.0 and 9.93-20.36) vs. 4.92% and 5.38% in other solid tumors (95% CI 4.21-5.76 and 4.52-5.76 in other solid tumors; p <0.001/p<0.001).

CONCLUSION

Our study indicates that anti-PD-1 is associated with a higher risk of all- and high-grade hepatotoxicity compared to anti-PD-L1, and primary liver cancers are associated with a higher risk of all- and high-grade hepatotoxicity compared to other solid tumors.

A74 INCREASING RATES OF CT IMAGING IN THE EMERGENCY DEPARTMENT AMONG PATIENTS WITH INFLAMMATORY BOWEL DISEASE

Background

Computed tomography (CT) imaging of the abdomen is often performed in the emergency department (ED) to exclude urgent pathology in patients with Inflammatory Bowel Disease (IBD). However, concerns over excessive radiation exposure from repeated use have led to expert consensus guidelines advising against CT imaging unless there is suspicion of complications (obstruction, perforation, abscess) or a non-IBD cause for symptoms.

Aims

Our study aimed to determine trends in abdominal CT utilization and findings among patients with IBD in the ED.

Methods

We performed a retrospective cohort study between 01/01/2009 and 31/12/2018 at a single academic center. We identified ED encounters for adults (age ≥17 years) with a pre-existing diagnosis of IBD from our institutional database and determined the proportion resulting in an abdominal CT scan within 72 hours of presentation. IBD subtypes were classified based on ICD-10 claims: K50.90* for Crohn’s disease (CD), K51.90* for Ulcerative colitis (UC) and IBD undifferentiated (IBDU) for patients with both claims. A time trend analysis was performed using a generalized linear model that assumed a Poisson distribution. CT scans were classified according to the dominant imaging finding. For this part we excluded studies performed within 1-month of surgery or those re-assessing a known abscess or malignancy.

Results

A total of 14783 encounters were identified. Among these encounters 3000 CT scans were performed: 2000 for patients with CD (21.9%), 652 for UC (16.5%) and 348 for IBDU (20.4%). The rates of CT utilization significantly increased by 2.7% (95% CI, 1.2–4.3; p=0.0004) in patients with CD, by 4.2% (95% CI, 1.7–6.7; p=0.0009) in patients with UC and by 6.3% in patients with IBDU (95% CI, 2.5–10.0; p=0.0011). Among the eligible CT scans performed for CD, the following dominant findings were reported: normal (25%), inflammation (23%), obstruction (23%), penetrating (18%) and unrelated to IBD (8.6%). In contrast, the following findings for patients with UC were reported: normal (20%), inflammation (39%), obstructive (19%), penetrating (8%) and unrelated to IBD (15%).

Conclusions

In this single center study, a steady increase in CT utilization in the ED was observed in patients with IBD. Interestingly, only a small proportion of the CT scans demonstrated urgent findings. Future studies are required to determine the factors that contribute to the ongoing increase in CT utilization in this patient population.

Funding Agencies

None

SARS-CoV-2 Viral Load Predicts Mortality in Patients with and without Cancer Who Are Hospitalized with COVID-19

Patients with cancer may be at increased risk of severe coronavirus disease 2019 (COVID-19), but the role of viral load on this risk is unknown. We measured SARS-CoV-2 viral load using cycle threshold (C_T) values from reverse-transcription polymerase chain reaction assays applied to nasopharyngeal swab specimens in 100 patients with cancer and 2,914 without cancer who were admitted to three New York City hospitals. Overall, the in-hospital mortality rate was 38.8% among patients with a high viral load, 24.1% among patients with a medium viral load, and 15.3% among patients with a low viral load (p < 0.001). Similar findings were observed in patients with cancer (high, 45.2% mortality; medium, 28.0%; low, 12.1%; p = 0.008). Patients with hematologic malignancies had higher median viral loads (C_T = 25.0) than patients without cancer (C_T = 29.2; p = 0.0039). SARS-CoV-2 viral load results may offer vital prognostic information for patients with and without cancer who are hospitalized with COVID-19.

COVID-19 Severity and Outcomes in Patients With Cancer: A Matched Cohort Study

PURPOSE

SARS-CoV-2 (COVID-19) is a systemic infection. Patients with cancer are immunocompromised and may be vulnerable to COVID-related morbidity and mortality. The objectives of this study were to determine if patients with cancer have worse outcomes compared with patients without cancer and to identify demographic and clinical predictors of morbidity and mortality among patients with cancer.

METHODS

We used data from adult patients who tested positive for COVID-19 and were admitted to two New York-Presbyterian hospitals between March 3 and May 15, 2020. Patients with cancer were matched 1:4 to controls without cancer in terms of age, sex, and number of comorbidities. Using Kaplan-Meier curves and the log-rank test, we compared morbidity (intensive care unit admission and intubation) and mortality outcomes between patients with cancer and controls. Among those with cancer, we identified demographic and clinical predictors of worse outcomes using Cox proportional hazard models.

RESULTS

We included 585 patients who were COVID-19 positive, of whom 117 had active malignancy, defined as those receiving cancer-directed therapy or under active surveillance within 6 months of admission. Presenting symptoms and in-hospital complications were similar between the cancer and noncancer groups. Nearly one half of patients with cancer were receiving therapy, and 45% of patients received cytotoxic or immunosuppressive treatment within 90 days of admission. There were no statistically significant differences in morbidity or mortality (P = .894) between patients with and without cancer.

CONCLUSION

We observed that patients with COVID-19 and cancer had similar outcomes compared with matched patients without cancer. This finding suggests that a diagnosis of active cancer alone and recent anticancer therapy do not predict worse COVID-19 outcomes and therefore, recommendations to limit cancer-directed therapy must be considered carefully in relation to cancer-specific outcomes and death.

Abstract S10-01: COVID-19 severity and outcomes in hospitalized patients with cancer at a New York City tertiary medical center: A matched cohort study

Background: New York City has been at the epicenter of the SARS-CoV-2 (COVID-19) pandemic. Immunocompromised cancer patients may be more vulnerable to COVID-related morbidity and mortality. The objectives of this study were to determine if patients with cancer have worse outcomes compared to their noncancer counterparts and to identify potential demographic and clinical predictors of morbidity and mortality among cancer patients.

Methods: We used data from a retrospective observational cohort of adult patients who tested positive for COVID-19 at New York-Presbyterian hospitals between March 3 and April 25, 2020. Patients with active cancer were matched 1:4 to noncancer controls on age, gender, and diabetes status. Using Kaplan-Meier curves and the log-rank test, we compared morbidity (intensive care unit admission and intubation) and mortality outcomes between cancer patients and controls. We identified demographic and clinical predictors of worse outcomes using Cox Proportional Hazard models. Hazard ratios and 95% confidence intervals were calculated for all estimates.

Results: We included 445 COVID-19 positive adult patients of whom 89 had active malignancy. Among cancer patients, the median age was 72 years, 54% were male, and 52% were non-white. Presenting symptoms were similar between cancer and noncancer groups. Nearly half of cancer patients were on active treatment including cytotoxic and immunosuppressive therapy, and 40.9% of patients received cytotoxic treatment within 90 days of admission. Both patients with and without cancer received hydroxychloroquine in similar proportions (64% vs. 65.5%), and more cancer patients received remdesivir (7.9% vs. 3.7%). Overall, age (HR 1.14; 95% CI 1.00-1.29; p=0.049), male sex (HR 1.43; 95% CI 1.04-1.96, p=0.07), dyspnea on presentation (HR 1.81, 95% CI 1.3-2.58; p=0.0005), and bilateral lung infiltrates (HR 1.94; 95% CI 1.30-2.89; p=0.001) were associated with worse outcomes. Observed complications were similar for cancer and noncancer patients, including myocardial infarction (3.4% vs. 4.2%), vasopressor requirements (24.7% vs. 26.2%), bacteremia (9% vs. 10.4%), and venous thromboembolic events (7.9% vs. 7.3%), respectively. There were no statistically significant differences in morbidity or mortality between cancer and noncancer patients (p=0.287).

Conclusion: We demonstrate that COVID-19 hospitalized patients with active malignancies have comparable morbidity and mortality to patients without cancer. In contrast to previous findings, we observed no differences in risk of ICU admission, intubation, or death between cancer and noncancer patients. Our findings suggest that active malignancy may not be a contributive risk factor in comparison to other significant comorbidities that may be more responsible for the unfavorable prognosis of COVID-19 in cancer patients. We should consider the consequences of limiting care for cancer patients on cancer-specific outcomes and mortality in the context of COVID-19.

Citation Format: Gagandeep Brar, Laura C. Pinheiro, Michael Shusterman, Brandon Swed, Evgeniya Reshentnyak, Orysya Soroka, Frank Chen, Samuel Yamshon, John Vaughn, Peter Martin, Doru Paul, Manuel Hidalgo, Manish A. Shah. COVID-19 severity and outcomes in hospitalized patients with cancer at a New York City tertiary medical center: A matched cohort study [abstract]. In: Proceedings of the AACR Virtual Meeting: COVID-19 and Cancer; 2020 Jul 20-22. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(18_Suppl):Abstract nr S10-01.

Hepatocellular Carcinoma Survival by Etiology: A SEER-Medicare Database Analysis

In the United States, hepatocellular carcinoma (HCC) survival varies with tumor characteristics, patient comorbidities, and treatment. The effect of HCC etiology on survival is less clearly defined. The relationship between HCC etiology and mortality was examined using Surveillance, Epidemiology, and End Results-Medicare data. In a cohort of 11,522 HCC cases diagnosed from 2000 through 2014, etiologies were identified from Medicare data, including metabolic disorders (32.9%), hepatitis C virus (8.2%), alcohol (4.7%), hepatitis B virus (HBV, 2.1%), rare etiologies (0.9%), multiple etiologies (26.7%), and unknown etiology (24.4%). After adjusting for demographics, tumor characteristics, comorbidities and treatment, hazard ratios (HRs) and survival curves by HCC etiology were estimated using Cox proportional hazard models. Compared with HBV-related HCC cases, higher mortality was observed for those with alcohol-related HCC (HR 1.49; 95% confidence interval [95% CI] 1.25-1.77), metabolic disorder-related HCC (HR 1.25; 95% CI 1.07-1.47), and multiple etiology-related HCC (HR 1.25; 95% CI 1.07-1.46), but was not statistically significant for hepatitis C virus-related, rare disorder-related, and HCC of unknown etiology. For all HCC etiologies, there was short median survival ranging from 6.1 months for alcohol to 10.3 months for HBV. Conclusion: More favorable survival was seen with HBV-related HCC. To the extent that HCC screening is more common among persons with HBV infection compared to those with other etiologic risk factors, population-based HCC screening, applied evenly to persons across all HCC etiology categories, could shift HCC diagnosis to earlier stages, when cases with good clinical status are more amenable to curative therapy.

AB0626 IMATINIB FOR THE TREATMENT OF SYSTEMIC SCLEROSIS: RATIONALE, CLINICAL EVIDENCE AND FUTURE DEVELOPMENT

Background:

Systemic sclerosis (SSc) is a chronic disorder of connective tissue affecting the skin and internal organs. The molecular mechanisms behind SSc are not entirely understood, but recent advances highlight key signalling pathways1(see Figure 1). Fibrosis disrupts tissue architecture resulting in organ dysfunction. This causes significant morbidity and mortality1, therefore there is a clear need for identifying efficacious antifibrotic treatment.

Imatinib is a tyrosine kinase inhibitor with established use in some malignancies, and existing evidence that it can treat SSc2.

Objectives:

The aim of this literature review is to summarise the current evidence and future developments of imatinib as antifibrotic treatment in SSc.

Methods:

PubMed headings “systemic sclerosis”, “scleroderma”, “imatinib” and synonyms were used. See Figure 2.

Results:

Lead author and yearStudy designPopulationIntervention (imatinib dose given daily)ResultsHinchcliff ME. 2016Case study1 female (F) with an 8-month history of diffuse cutaneous systemic sclerosis (dcSSc)400mgSevere adverse events (AEs)Pope J. 2014Early phase proof of concept trial10 with dcSSc.9 given 400mg, 1 placeboPoor drug tolerabilityPrey S. 2012Double blind RCT28 with SSc15 given 400mg, 13 placeboNo improvementKhanna D. 2011Phase I/IIa pilot trial20 with SScUp to 600mgAEs presentPope J. 2011Double blind RCT10 with SSc.9 given 400mg, 1 placeboNo improvement, AEs presentGordon J. 2014Open label, single arm, extension phase clinical trial17 with average disease duration of 3.5 years100-400mg↓ modified Rodnan skin score (mRSS)Fraticelli P. 2014Phase II pilot trial30 with SSc200mg↑ lung functionGuo L. 2012Case series6 F, Chinese pts with SSc200mg↓ mRSS and ↑ lung functionDivekar AA. 2011Single centre, open-label study15 with SSc100mg up to 600mg/day↑ lung functionSpiera RF. 20111-year, phase IIa, single-arm, open-label clinical trial30 with dcSSc400mg↓ mRSS and ↑ lung functionFreyhaus H. 2009Case report58yo F400mg↑ lung functionChung L. 2009Case report2 with early dcSSc200mg↓ mRSS and ↑ lung functionVan Daele PL. 2008Case report69yo F400mg↓ mRSS and ↑ lung functionP. P. Sfikakis. 2008Case report24yo F400mg↓ mRSS and ↑ lung function

9 studies showed imatinib had positive efficacy in the treatment of SSc. 5 showed no improvement or adverse effects.

Conclusion:

Overall, current evidence suggests that imatinib can be a useful drug to improve manifestations of SSc, for some. Despite inconclusive evidence, a dose-dependent relationship seems to exist for imatinib toxicities, with more research needed to ascertain a safe dose.

Gene expression profiles may distinguish patients that can benefit from imatinib3. Also, Notch signalling could be exploited to increase imatinib uptake into fibroblasts, thereby increasing efficacy4.

References:

[1]Pattanaik D et al. Pathogenesis of Systemic Sclerosis. Frontiers in Immunology. 2015;6: 272

[2]Distler JHW et al. Tyrosine kinase inhibitors for the treatment of fibrotic diseases such as systemic sclerosis: towards molecular targeted therapies. Annals of the Rheumatic Diseases. 2010;69: 48-51

[3]Chung L et al. Molecular framework for response to imatinib mesylate in systemic sclerosis. Arthritis and Rheumatology. 2009 Feb;60(2):584-91

[4]Harrach S et al. Notch Signaling Activity Determines Uptake and Biological Effect of Imatinib in Systemic Sclerosis Dermal Fibroblasts. Journal of Investigative Dermatology. 2019; 139(2):439-4475

Acknowledgments:

Skin Research Institute of Singapore

Disclosure of Interests:

None declared

Phase II randomized controlled trial (RCT) of medical intensive nutrition therapy (MINT) to improve chemotherapy (CT) tolerability in malnourished patients with solid tumor malignancies

12090

Background: Malnutrition is an underrecognized predictor of inferior cancer related outcomes. Subjective global assessment (SGA), a brief validated survey for malnutrition, may predict increased CT toxicity. This phase II RCT was performed to validate SGA as a predictive tool for malnutrition and to evaluate the impact of MINT on CT associated toxicity. Methods: CT naive pts screened by SGA were assigned to well-nourished (SGA A) or malnourished (SGA B/C) cohorts. Both cohorts were followed for CT delivery, toxicity, quality of life (QOL) by FACT-G, biomarkers, radiology, and survival. SGA B/C pts, stratified by regimen/disease, were randomized 1:1 to MINT vs. usual care. The MINT cohort received weekly registered dietician counseling and symptom assessment over the 8-week study period. Percent standard and planned CT doses were calculated. Wilcoxon rank sum tests were used for differences between groups, log-rank tests for survival, and multivariable linear regression for adjusted comparisons. Results: 186 eligible pts were enrolled (94 SGA A, 92 SGA B/C). SGA A were younger (median age [range]; 63 [22, 89] vs. 70 [22, 91], p = 0.011) and more fit (ECOG 0-1; 96.8% vs. 72.8%, p < 0.001). Baseline QOL was higher for SGA A (median [range], 87 [34, 115]) vs SGA B/C (70 [31, 101], p < 0.001). SGA A was associated with higher CT delivery: median proportion of planned CT (1 [Q1 0.87, Q3 1] vs 0.94 [0.70, 1], p = 0.022) and standard CT (0.91 [0.72, 1] vs. 0.74 [0.57, 0.95] p < 0.001). Adjusted for age/ECOG, SGA A remained associated with > 80% of planned (OR 2.32, p = 0.05) and standard (OR 2.33, p = 0.04) CT. SGA B/C pts (n = 92) were randomized to MINT vs usual care: median nutrition encounters MINT 5.5 vs. usual care 0.5; we observed no differences in CT delivery: median proportion of planned CT (0.91 [0.69, 1] vs. 0.94 [0.74, 1], p = 0.84) and standard CT (0.75 [0.58, 0.96] vs 0.71 [0.52, 0.99], p = 0.59). SGA A was associated with a longer 12-month survival (77.8% [95% CI 69.6%, 86.9%]) vs. B/C (53.3% [42.8%, 66.4%], p < 0.0001; 12-month survival was similar for MINT (52.3% [38.1%, 71.9%]) vs usual care (54.4% [40.2%, 73.6%], p = 0.58). Conclusions: SGA is a validated tool to characterize malnutrition in pts receiving CT. Malnourished pts received significantly less CT, experienced worse baseline QOL, and had worse 12-month survival. Intensive medical nutrition therapy was not associated with differences in CT associated toxicity. Novel nutritional interventions are still needed to improve pt outcomes.

Immune Checkpoint Blockade in Combination with Stereotactic Body Radiotherapy in Patients with Metastatic Pancreatic Ductal Adenocarcinoma

PURPOSE

The effectiveness of immune checkpoint inhibitors (ICI) is limited in pancreatic ductal adenocarcinoma (PDAC). We conducted a phase I study to evaluate the safety of ICI with stereotactic body radiation therapy (SBRT) in patients with metastatic PDAC.

PATIENTS AND METHODS

Patients enrolled must have received at least one line of prior systemic chemotherapy for metastatic disease. Cohorts A1 and A2 received durvalumab every 2 weeks plus either 8 Gy in one fraction of SBRT on day 1 or 25 Gy in five fractions on day -3 to +1. Cohorts B1 and B2 received durvalumab plus tremelimumab every 4 weeks and either 8 Gy in one fraction of SBRT on day 1 or 25 Gy in five fractions on day -3 to +1. ICIs were continued until unacceptable toxicity or disease progression. The primary objective was the safety and feasibility of treatment. Objective response was assessed in lesions not subjected to SBRT.

RESULTS

Fifty-nine patients were enrolled and 39 were evaluable for efficacy. No dose-limiting toxicities were seen. The most common adverse event was lymphopenia. Two patients achieved a partial response (one confirmed and the other unconfirmed). The overall response rate was 5.1%. Median PFS and OS was 1.7 months [95% confidence intervals (CI), 0.8-2.0 months] and 3.3 months (95% CI, 1.2-6.6 months) in cohort A1; 2.5 months (95% CI, 0.1-3.7 months) and 9.0 months (95% CI, 0.5-18.4 months) in A2; 0.9 months (95% CI, 0.7-2.1 months) and 2.1 months (95% CI, 1.1-4.3 months) in B1; and 2.3 months (95% CI, 1.9-3.4 months) and 4.2 months (95% CI, 2.9-9.3 months) in B2.

CONCLUSIONS

The combination of ICI and SBRT has an acceptable safety profile and demonstrates a modest treatment benefit in patients with metastatic PDAC.

The role of pembrolizumab in the treatment of PD-L1 expressing gastric and gastroesophageal junction adenocarcinoma

Gastric cancer is a leading cause of cancer-related death worldwide. Recent evidence suggests that gastric cancer is a complex and heterogenous disease with emerging subtypes shown to affect response to treatment and survival. Immunotherapy is an advancing field and immune checkpoint inhibitors have become standard treatment options in numerous tumor types. In this review, we discuss the current and evolving use of checkpoint blockade, focusing on the anti-PD-1 inhibitor, pembrolizumab, for use in advanced gastric and gastroesophageal cancers.

A Pilot Study of the PD-1 Targeting Agent AMP-224 Used With Low-Dose Cyclophosphamide and Stereotactic Body Radiation Therapy in Patients With Metastatic Colorectal Cancer

BACKGROUND

The prognosis of metastatic colorectal cancer (mCRC) is poor. We assessed the feasibility, safety, and efficacy of the anti-programmed cell death 1 fusion protein AMP-224 in combination with low-dose cyclophosphamide and stereotactic body radiation (SBRT) treatment in patients with mCRC refractory to standard chemotherapy.

PATIENTS AND METHODS

Fifteen patients were enrolled. Six received SBRT 8 Gy on day 0 (dose level 1), whereas 9 received 8 Gy on days -2 to day 0. All received cyclophosphamide 200 mg/m² intravenously (I.V.) on day 0. On day 1, both groups received AMP-224 10 mg/kg I.V., repeated every 2 weeks for a total of 6 doses. Primary end points were feasibility and safety.

RESULTS

Ten (67%) patients completed 6 doses of AMP-224; 5 patients (33%) discontinued treatment because of disease progression. No dose-limiting toxicity was observed; 9 patients (60%) experienced treatment-related adverse events, all Grade 1 or 2. No objective response was noted; 3 patients (20%) had stable disease. Median progression-free survival and overall survival were 2.8 months (95% confidence interval [CI], 1.2-2.8 months) and 6.0 months (95% CI, 2.8-9.6 months), respectively. M2 macrophage polarization was present in the pretreatment tumor biopsy samples, but not post-treatment samples.

CONCLUSION

AMP-224 in combination with SBRT and low-dose cyclophosphamide was well tolerated, however, no significant clinical benefit was observed in patients with mCRC.

Tremelimumab in Combination With Microwave Ablation in Patients With Refractory Biliary Tract Cancer

Treatment options for patients with advanced biliary tract cancer are limited. Dysregulation of the immune system plays an important role in the pathogenesis of biliary tract cancer (BTC). This study aimed to investigate whether tremelimumab, an anti-CTLA4 (cytotoxic T-lymphocyte-associated protein 4) inhibitor, could be combined safely with microwave ablation to enhance the effect of anti-CTLA4 treatment in patients with advanced BTC. Patients were enrolled to receive monthly tremelimumab (10 mg/kg, intravenously) for six doses, followed by infusions every 3 months until off-treatment criteria were met. Thirty-six days after the first tremelimumab dose, patients underwent subtotal microwave ablation. Interval imaging studies were performed every 8 weeks. Adverse events (AEs) were noted and managed. Tumor and peripheral blood samples were collected to perform immune monitoring and whole-exome sequencing (WES). Twenty patients with refractory BTC were enrolled (median age, 56.5 years). No dose-limiting toxicities were encountered. The common treatment-related AEs included lymphopenia, diarrhea, and elevated transaminases. Among 16 patients evaluable for efficacy analysis, 2 (12.5%) patients achieved a confirmed partial response (lasting for 8.0 and 18.1 months, respectively) and 5 patients (31.3%) achieved stable disease. Median progression free survival (PFS) and overall survival (OS) were 3.4 months (95% confidence interval [CI], 2.5-5.2) and 6.0 months (95% CI, 3.8-8.8), respectively. Peripheral blood immune cell subset profiling showed increased circulating activated human leukocyte antigen, DR isotype ([HLA-DR] positive) CD8⁺ T cells. T-cell receptor (TCR)β screening showed tremelimumab expanded TCR repertoire, but not reaching statistical significance (P = 0.057). Conclusion: Tremelimumab in combination with tumor ablation is a potential treatment strategy for patients with advanced BTC. Increased circulating activated CD8⁺ T cells and TCR repertoire expansion induced by tremelimumab may contribute to treatment benefit.

The effect of anti-CTLA4 treatment on peripheral and intra-tumoral T cells in patients with hepatocellular carcinoma

BACKGROUND

Checkpoint inhibitors have recently been approved for the treatment of patients with hepatocellular carcinoma (HCC). However, biomarkers, which will help identify patients responding to therapy, are missing. We recently tested the combination of anti-CTLA4 treatment (tremelimumab) with loco-regional therapy in patients with HCC and reported a partial response rate of 26%.

METHODS

Here, we report updated survival analyses and results from our immune monitoring studies on peripheral blood mononuclear cells (PBMCs) and tumors from these patients.

RESULTS

Tremelimumab therapy increased CD4+-HLA-DR+, CD4+PD-1+, CD8+HLA-DR+, CD8+PD-1+, CD4+ICOS+ and CD8+ICOS+ T cells in the peripheral blood of the treated patients. Patients with higher CD4+PD1+ cell frequency at baseline were more likely to respond to tremelimumab therapy. PD-1 expression was increased on alpha fetal protein (AFP) and survivin-specific CD8 T cells upon tremelimumab treatment. An increase of tumor infiltrating CD3+ T cells were also seen in these patients. Immunosequencing of longitudinal PBMC showed that one cycle of tremelimumab significantly decreased peripheral clonality, while no additional effects were seen after loco-regional therapy.

CONCLUSION

In summary, we observed a clear activation of T cell responses in HCC patients treated with tremelimumab and identified potential biomarkers which will help identify patients responding to immunotherapy with anti-CTLA4.

Immunotherapy: Current Status and Future Perspectives

Hepatocellular carcinoma (HCC) has an increasing incidence and dismal prognosis, with few systemic treatments approved, including several small molecule tyrosine kinase inhibitors. The application of immune checkpoint inhibitors (ICIs) to HCC has resulted in durable activity, and further evaluation is ongoing. In this review, we discuss the immunologic principles and the mechanism of action of the ICIs and present the relevant clinical data. Furthermore, we provide an overview of the current and emerging immunotherapeutic approaches for HCC, such as combination treatments, vaccines, and cellular therapies.

Hepatocellular carcinoma (HCC) survival by etiology: A SEER-Medicare database analysis

201

Background: HCC is the 6thmost common occurring cancer worldwide and the 4th leading cause of cancer mortality, with a survival of 6-9 months. While survival varies by stage at diagnosis and treatment, the effect of HCC etiology on survival is unclear. We analyzed the SEER-Medicare database to evaluate whether HCC survival varied by etiology, after adjusting for stage, treatment, and survival. Methods: A total of 11,522 SEER-Medicare HCC cases (ICD-O-3 codes C22 for topography, 8170-8175 for morphology) met criteria for the Cox proportional hazard analyses to assess survival differences among the risk factors for hepatitis C virus (HCV) infection, hepatitis B virus (HBV) infection, alcohol disorders, and metabolic disorders. These analyses were adjusted for covariates for gender, age at diagnosis, race, ethnicity, tumor size and extent of disease, a modified Charlson Index of comorbidities, and treatments that included resection, transplantation, ablation, arterial directed therapy and radiotherapy. Cases with multiple and unknown etiologies were included in analyses, however genetic disorders and primary biliary cirrhosis were excluded due to their rarity. Results: HBV associated cases had the highest proportion of single nodules (40% vs 33% overall), localized stage disease (57% vs 49%), treatment (40% vs 27%), and greatest frequency of resection (18.6% vs 9%). Non-Hispanic Asians/Pacific Islanders accounted for 69% of HBV infection-related HCC cases but only 16% of all cases. HBV associated cases had better survival than did HCC cases with other etiologies. Specifically, after adjusting for demographic and clinical attributes, compared to cases with HBV infection, the risk of death was highest for alcohol-related HCC (HR=1.69; 95%CI:1.42-2.01) followed by multiple etiologies (HR = 1.40; 95% CI: 1.20-1.64), metabolic disorders (HR = 1.32; 95% CI: 1.13-1.55), HCV infection (HR = 1.30; 95% CI: 1.10-1.53), and HCC of unknown etiology (HR = 1.22; 95% CI: 1.04-1.43). Conclusions: Persons with HBV associated HCC had better survival than persons with HCC of other etiologies. Efforts to identify people with any etiologic risk factors for HCC, treat their conditions, and screen for HCC may improve overall survival.

Combined immune checkpoint inhibition (ICI) with tremelimumab and durvalumab in patients with advanced hepatocellular carcinoma (HCC) or biliary tract carcinomas (BTC)

336

Background: Prognosis in advanced HCC and BTC is unfavorable, and 5-year overall survival (OS) rate is less than 20% and 10%, respectively. Single agent ICI in HCC has response rates (RR) of 20%, while early data in BTC reported 17.4% RR. Dual ICI has increased RR in other malignancies. The purpose of this study was to explore the efficacy of the combination of anti-CTLA4 (tremelimumab) with anti-PD-L1 (durvalumab) in advanced HCC and BTC. Methods: Eligible patients with advanced HCC or BTC who had received (or refused) at least one prior therapy, received monthly tremelimumab 75 mg in combination with durvalumab 1500 mg for 4 doses followed by monthly durvalumab 1500 mg monotherapy until progression of disease or unacceptable toxicity. Response was assessed with CT scan every 8 weeks. Adverse events (AEs) were recorded and managed. The primary endpoint is 6-month progression free survival (PFS). Results: Twenty-two patients were enrolled, 10 with advanced HCC and 12 with advanced BTC. Male to female ratio was 14:8, with median age of 62.5 years (range 19-80). Grade 3/4 treatment-related AEs included lymphocytopenia, hyponatremia, bullous dermatitis, maculopapular rash, mucositis, hypophosphatemia, anaphylaxis, dyspnea, pleural effusion, and pain. Twenty patients were evaluable for response analysis. Two patients (2/10, 20%) achieved a confirmed partial response (both with HCC, lasting 6.9 and 17.6 months), while 9 patients (4 [40%] with HCC and 5 [41.7%] with BTC) had stable disease, with the longest duration of 9.3 months (in an HCC patient). Disease control rate is 60% in HCC and 41.7% in BTC, respectively. In this small pilot cohort, median PFS was 3.1 months (95% CI 0.8 to 4.6 months) and median OS was 5.45 months (95% CI 4.60 to 8.3 months) among BTC patients, while HCC patients median PFS was 7.8 months (95% CI 2.6 to 10.6 months) and median OS was 15.9 (95% CI 7.1 to 16.3 months). Conclusions: Combined ICI with tremelimumab and durvalumab is well tolerated and demonstrates promising activity in patients with advanced HCC and BTC. Clinical trial information: NCT02821754.

Immune checkpoint inhibition (ICI) in combination with SBRT in patients with advanced pancreatic adenocarcinoma (aPDAC)

192

Background: Chemotherapy in aPDAC has resulted in only modest improvements in outcome. The effectiveness of ICI monotherapy is also limited in PDAC, suggesting an immunogenic inert tumor microenvironment. SBRT is safe and effective in locally advanced PDAC and exhibits enhanced antitumor immunity. We hypothesize that ICI plus SBRT will improves immunomodulatory effects of ICI in patients with aPDAC resulting in a greater clinical benefit. Methods: Eligible patients with aPDAC were enrolled to four different treatment cohorts. Cohort 1: Durvalumab (Durva) 1500 mg every 4 weeks + SBRT 1 fraction x 8Gy on day 1. Cohort 2: SBRT 5 fractions x 5Gy followed by Durva. Cohort 3: Durva + Tremelimumab (Treme) 75 mg every 4 weeks + SBRT 1 fraction x 8Gy on day 1. Cohort 4: SBRT 5 fractions x 5Gy followed by Durva + Treme. This was continued until unacceptable toxicity or progression of disease. A biopsy was performed at baseline and pre-cycle 2 of treatment for exploratory correlative analysis. The primary objective was to evaluate the safety and feasibility of combining ICI and SBRT to enhance the efficacy of ICI. Results: 51 patients with aPDAC were enrolled and 31 patients were evaluable for the efficacy. The most commonly TRAEs were lymphopenia. Grade 3-4 AEs were lymphopenia and anemia. No dose limiting toxicities were seen. Out of total 31 evaluable patients, 1 patient achieved a confirmed partial response seen in Cohort 1 and 2 patients in Cohort 4, and 7 stable disease across the 4 treatment arms. Median PFS and OS was 1.7 months (95% CI 0.7-2.8 months) and 3.4 months (95% CI 0.9-11.4 months) in cohort 1; 2.6 months (95% CI 2.1-4.7 months) and 9.1 months (95% CI 3.4-18.7 months)in cohort 2; 1.6 months (95% CI 0.5-4.0 months) and 3.0 months (95% CI 0.7-6.6 months) in cohort 3; and 3.2 months (95% CI 1.5-16.5months) and 6.4 months (95% CI 1.5-17.6 months) in cohort 4. Conclusions: The combination of ICI and SBRT is safe and well tolerated in patients with aPDAC. The overall response rate of 9.6% including 2 patients who achieved a durable partial response lasting over 12 months, suggests meaningful clinical activity. This signifies that ICI and SBRT is a potential new treatment for aPDAC. Clinical trial information: NCT02311361.

Current frontline approaches in the management of hepatocellular carcinoma: the evolving role of immunotherapy

Hepatocellular carcinoma (HCC) is a major cause of cancer-associated mortality worldwide and is expected to rise. Patients with early-stage disease may have a good prognosis with a 5-year survival rate of greater than 70%. However, the majority of patients are diagnosed with late-stage disease with a dismal overall survival rate of less than 16%. Therefore, there is a great need for advances in the treatment of advanced HCC, which for approximately the past decade, has been sorafenib. Immunotherapy is an evolving cancer treatment and has shown promise in treating patients with advanced HCC. In this review, we discuss the current standard of care for advanced HCC and then discuss the evolving role of immunotherapies.

Multiomic molecular comparison of primary versus metastatic pancreatic tumors

213

Background: Pancreatic cancer metastasizes very early, as evidenced by the fact that > 70% of patients with operable disease ultimately develop metastases. Thus, it is likely that the molecular characteristics of primary pancreatic tumors are similar to metastatic lesions. We compared the frequency of genetic alterations and protein expression from primary vs. metastatic pancreatic tumors, and from metastases from different sites. By focusing on actionable genetic and proteomic information, we sought to explore whether targeted therapies could be tailored to patients at metastatic progression based on primary surgical material. Methods: Next generation DNA sequencing (NGS) data of 208 genes and a limited set of protein markers were analyzed from pancreatic tumors of 431 patients enrolled in the Know Your Tumor initiative. Of the 208 genes tested, mutations in 70 were considered potentially actionable based on preclinical and clinical evidence. We compared 146 primary pancreatic tumors against 285 metastatic lesions, and examined subgroups for liver vs. lung vs. other metastatic lesions. Molecular alterations were compared between independent groups for each gene/protein using Fisher’s exact test. Significance was assessed using a false discovery rate adjusted q-value threshold of 0.05. Results: No differences in the specific mutation or expression pattern were observed between primary vs. metastatic lesions, nor across the site of metastasis after correcting for multiple hypotheses. Even the proportion of actionable alterations (including mutations in the homologous recombination DNA repair pathway) was similar across subgroups. Conclusions: Comparison of the muli-omic profile of primary vs. metastatic pancreatic adenocarcinoma reveals that the molecular architecture is very similar, and that actionable alterations are identified at the same frequency. This is unlike the data observed from other solid tumors, (e.g. colon and breast cancer), in which substantial molecular discordance and heterogeneity exists between primary tumors and metastatic sites, but is consistent with the belief that primary pancreatic cancers metastasize early and thus are molecularly indistinguishable from metastatic lesions.

Safe and effective use of rivaroxaban for treatment of cancer-associated venous thromboembolic disease: a prospective cohort study

Low-molecular weight heparin (LMWH) has been the standard of care for treatment of venous thromboembolism (VTE) in patients with cancer. Rivaroxaban was approved in 2012 for the treatment of pulmonary embolism (PE) and deep vein thrombosis (DVT), but no prior studies have been reported specifically evaluating the efficacy and safety of rivaroxaban for cancer-associated thrombosis (CAT). Under a Quality Assessment Initiative (QAI), we established a Clinical Pathway to guide rivaroxaban use for CAT and now report a validation analysis of our first 200 patients. A 200 patient cohort with CAT (PE or symptomatic, proximal DVT), whose full course of anticoagulation was with rivaroxaban, were accrued. In competing risk analysis, primary endpoints at 6 months included new or recurrent PE or symptomatic proximal lower extremity DVT, major bleeding, clinically-relevant non-major bleeding leading to discontinuation of rivaroxaban, or death. In competing risk analysis, the 6 months cumulative incidence of new or recurrent VTE was 4.4 % (95 % CI = 1.4–7.4 %), major bleeding was 2.2 % (95 % CI = 0−4.2 %) and all-cause mortality 17.6 % (95 % CI = 11.7–23.0 %). In this cohort of 200 patients with active cancer and CAT the rates of new or recurrent VTE and major bleeding were comparable to the cancer subgroup analysis from the EINSTEIN studies. The results of our Clinical Pathway provide guidance on Rivaroxaban use for treatment of CAT, and suggest that safety and efficacy is preserved, compared with past-published experience with LMWH.

Outcomes of phacoemulsification in patients with dry eye

PURPOSE

To evaluate the outcomes of phacoemulsification in patients with dry eye.

SETTING

Department of Ophthalmology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.

METHODS

This study included 25 eyes of 23 patients with dry eye having phacoemulsification. Dry eye was defined as Schirmer I with lidocaine hydrochloride (Xylocaine) score of 5.0 mm after 5 minutes, a tear-film breakup time (TFBUT) of less than 5 seconds, or both. Data were retrospectively analyzed for preoperative and postoperative tear function, postoperative complications, and final visual outcomes.

RESULTS

Of the 23 patients, 18 had age-related dry eye and 5 had secondary Sjögren's syndrome. Twenty-two eyes had predominant aqueous deficiency (Schirmer I with Xylocaine score of 5.0 mm or less), and 3 had a Schirmer score between 6.0 mm and 9.0 mm. The TFBUT was 5 seconds or less in 17 eyes and between 6 seconds and 9 seconds in 8 eyes. The mean preoperative Schirmer score was 4.80 mm +/- 2.01 (SD) (range 2.0 to 9.0 mm) and the mean postoperative score, 3.80 +/- 2.40 mm (range 0 to 7.0 mm). The mean preoperative TFBUT was 4.00 +/- 1.87 seconds (range 0 to 9 seconds) and the mean score at the last follow-up, 3.40 +/- 1.60 seconds (range 0 to 8 seconds). Postoperatively, 8 eyes had superficial punctate keratopathy and 8 had an epithelial defect. The final visual acuity was 6/6 in 13 eyes, 6/9 to 6/12 in 8 eyes, and 6/18 to 6/60 in 4 eyes.

CONCLUSION

Phacoemulsification was safe and led to minimal complications in patients with age-related dry eye with or without associated systemic disorders.

Respiratory mechanics in very low birth weight infants during continuous versus intermittent gavage feeds

This study was designed to determine whether respiratory mechanics in stable, very low birth weight infants changed after replacing intermittent feeds with continuous feeding. We measured static respiratory system compliance, respiratory system resistance, functional residual capacity (FRC), and tidal volume immediately before feeds and at 20, 60, and 120 min after feeds, and again the next day on continuous feeds. Patients selected for enrollment into the study needed to fulfill the following criteria: 1) birth weight and postnatal weight < 1,500 g, 2) no need for mechanical ventilation, positive airway pressure, or supplemental oxygen, 3) receiving and tolerating at least 100 mL/kg/day of intermittent gavage feeds, and 4) no change in methylxanthine or diuretic dosage for 3 days before the study. Respiratory mechanics were measured using the SensorMedics 2600 Pediatric Pulmonary Cart (Yorba Linda, CA). We studied 16 infants (gestational age 28.3 +/- 3.7 weeks, mean +/- SD) at a postnatal age of 10-82 days. The average interindividual coefficient of variance was 20 +/- 2% for static compliance, 35 +/- 6% for resistance, 18 +/- 3% for FRC, and 19 +/- 3% for tidal volume. Repeated-measures analysis of variance did not reveal any significant difference in respiratory mechanics with intermittent vs. continuous feeding. The data suggest that static respiratory mechanics in stable, very low birth weight infants are not affected by changing enteral feeds from intermittent gavage to a continuous schedule.