Citations

80 Background: Several previous systematic reviews and meta-analyses have attempted to summarize toxicity of Immune Checkpoint inhibitors (ICIs). However, very soon after each one of these reviews has been published, it became outdated. ICIs are currently used in 14 different cancers and data is rapidly evolving from new clinical trials. A living Systematic review, which is defined as a systematic review that is continually updated to incorporate relevant new evidence as it becomes available, is necessary in this situations. Methods: In order to dynamically display content -- including textual data, tables, charts, and graphs – standard data formats and protocols were designed for various components of the systematic reviews carried out by researchers. Given these standardized formats, software was written to interpret this data and output the information in the appropriate format, such as a forest plot or data table. Finally, a dynamic interface that enables user inputs (such as which aspect of the meta-analysis to view) and displays the associated output was designed. The overall living Systematic Review infrastructure includes monthly literature searches, cumulative meta-analysis, and an online reporting platform. Results: We have developed a Living Systematic Review engine that can take in standardized data and reflect this data in an interactive, intuitive manner in the form of text, tables, and plots. This interface can also be manipulated via user input to organize and sort data tables or omit/highlight specific pieces of data. Conclusions: We have initiated the first living systematic review in immune-oncology that will be continuously updated, incorporating relevant new evidence as it becomes available, and will provide accurate and up to date toxicity estimates to support clinical decision making. The Living Systematic Review interface allows users to easily and intuitively access the most recent available clinical evidence on toxicity of ICIs.

Abstract Background: The incidence and types of hematologic complications from immune check point inhibitors are not well known. We conducted this review to describe immune-mediated hematologic complications reported in clinical trials, case series, and case reports. Methods: A pre-defined comprehensive search strategy was used to identify case reports, case series, and clinical trials using PubMed. Any study that reported hematologic complications was included. Data were extracted for demographic characteristics and occurrence of immune-mediated hematologic complications. We pooled the data to calculate the frequency of immune-mediated hematologic adverse effects. Results: A total of 689 of studies were retrieved using the search criteria and 75 were included in the analysis (31 case reports and case series and 44 clinical trials). There were 44 patients reported having immune-mediated hematologic complications, 4 of them in clinical trials. The complications included aplastic anemia, autoimmune hemolytic anemia, cryoglobulinemia, graft versus host disease, hemophilia A (acquired), immune neutropenia, immune thrombocytopenia, macrophage activation syndrome, myelodysplastic syndrome, pure red cell aplasia, and thrombotic thrombocytopenic purpura. However, the overall rates were very low, ranging from 1-2.2% in clinical trials. Immune thrombocytopenia was the most common (29.5%), followed by autoimmune hemolytic anemia (15.9%), and immune neutropenia (13.6%). Immune-mediated hematologic complications were reported in all classes of checkpoint inhibitors including anti-programmed cell death protein 1 (nivolumab and pembrolizumab), anti-programmed death ligand 1 (avelumab and durvalumab), and anti-cytotoxic T-lymphocyte-associated protein 4 inhibitors (ipilimumab and tremelimumab). Among patients reported in case reports and case series, the median age was 57 years (range, 29-85) and most were males (52.9%). The majority of the complications occurred in patients treated with ipilimumab (38.8%), nivolumab (27.7%) and pembrolizumab (16.0%). The onset was usually within the first week of receiving the first dose but could occur up to 17 months after drug initiation. Indefinite discontinuation of the immunotherapy was the mainstay of treatment resulting in resolution of complications in the majority (74.5%) of the patients. Two patients were re-challenged with the same checkpoint inhibitor and one experienced a relapse of immune cytopenia (autoimmune hemolytic anemia). Conclusion: Immune-mediated hematologic complications associated with checkpoint inhibitors are rare. They are usually reversible after discontinuation of such treatment. Relapses may occur with re-challenge. Disclosures No relevant conflicts of interest to declare.

Background Male breast cancer (MBC) is a rare disease for which there is limited understanding of treatment patterns and prognostic factors. Methods Men with TNM stage I to stage III breast cancer diagnosed between 2004 and 2014 in the National Cancer Data Base were included. Trends in treatment modalities were described using the average annual percentage change (AAPC) and estimated using Joinpoint software for the analysis of trends. Kaplan‐Meier curves and the multivariate Cox proportional hazards regression model were used to compare survival between subgroups and to identify prognostic factors. Results A total of 10,873 MBC cases were included, with a median age at diagnosis of 64 years. Breast‐conserving surgery was performed in 24% of patients, and 70% of patients undergoing breast conservation received radiotherapy. Approximately 44% of patients received chemotherapy, and 62% of patients with estrogen receptor–positive disease received endocrine therapy. Oncotype DX was ordered in 35% of patients with lymph node–negative, estrogen receptor–positive/human epidermal growth factor receptor 2 (HER2)‐negative tumors. During the study period, there was a significant increase in the rates of total mastectomy, contralateral prophylactic mastectomy, radiotherapy after breast conservation, ordering of Oncotype DX, and the use of endocrine therapy ( P < .05). On multivariate analysis, factors found to be associated with worse overall survival were older age, black race, higher Charlson Comorbidity Index, high tumor grade and stage of disease, and undergoing total mastectomy. Residing in a higher income area; having progesterone receptor–positive tumors; and receipt of chemotherapy, radiotherapy, and endocrine therapy were associated with better overall survival. Conclusions Despite the lack of prospective randomized trials in patients with MBC, the results of the current study demonstrated that the treatment of this disease has evolved over the years. These findings further the understanding of the modern treatment and prognosis of MBC, and identify several areas for further research.

e23156 Background: A direct meta-analysis was performed to explore the efficacy and safety of direct oral factor Xa inhibitors with dalteparin in patients with cancer associated acute venous thromboembolism (VTE). Also, the comparative efficacy and safety of apixaban, rivaroxaban, and edoxaban was assessed with a network meta-analysis. Methods: MEDLINE, CENTRAL, and EMBASE were searched for trials comparing direct oral anticoagulants (DOACs) to dalteparin for the management of cancer associated acute VTE. A network meta-analysis using both frequentist and Bayesian methods was performed to analyze VTE recurrence, major and clinically relevant non-major bleeding (CRNMB). Results: Three randomized control trials, at low risk of bias, enrolled 1,739 patients with cancer associated VTE. Direct comparison showed a lower rate of VTE recurrence in DOAC compared to dalteparin groups (odds Ratio [OR]:0.48, 95% Confidence interval [CI]:0.24-0.96; I2:46%). Indirect comparison suggested that apixaban had greater reduction in VTE recurrence compared to dalteparin (OR: 0.10; 95% CI: 0.01–0.82), but not rivaroxaban or edoxaban. Apixaban also had the highest probability of being ranked most effective. By direct comparisons, there was an increased likelihood of major bleeding in the DOAC group compared to dalteparin (OR: 1.70; 95% CI: 1.04–2.78). CRNMB did not differ. Indirect estimates were imprecise. Subgroup analyses in gastrointestinal cancers suggested that dalteparin may have the lowest risk of bleeding whereas estimates in urothelial cancer were imprecise. Conclusions: DOACs appear to lower the risk of VTE recurrence compared to daltaparin while increasing major bleeding. Apixaban may be associated with the lowest risk of VTE recurrence compared to the other DOACs.

6596 Background: Several previous systematic reviews and meta-analyses have attempted to summarize toxicity of Immune checkpoint inhibitors (ICIs). However, very soon after each one of these reviews has been published, it became outdated. ICIs are currently used in 14 different cancers and data is rapidly evolving from new clinical trials. A living Systematic review, which is defined as a systematic review that is continually updated to incorporate relevant new evidence as it becomes available, is necessary in this situations. Therefore, we performed an updated systematic review and a meta-analysis which will serve as a foundation of a living Systematic review. Methods: MEDLINE, EMBASE and Cochrane were searched to identify phase 2 and 3 RCTs of PD-1/PD-L1 ICIs. Included studies compared either immunotherapy alone or combination with existing standard of care treatment and reported data for AE’s of interest. DerSimonian-Laird random effects Meta-Analysis was performed to derive pooled odds Ratio (OR) estimates for AE’s of interest. An infrastructure of a living systematic review is being developed and it includes monthly literature searches, cumulative meta-analysis and an online reporting platform. Results: We screened 6746 studies and 31 phase 3 and 2 phase 2 RCTs (n = 21,421) were included in the analysis. 22 RCTs used PD-1/PD-L1 ICIs as a single agent and 11 as a combination therapy. Selected toxicity estimates are summarized in a table. Conclusions: The meta-analysis updates previously published toxicity estimates and provides additional information about the risk of toxicities in single versus combination regimens. We have initiated the first living systematic review in oncology that will be continuously updated, incorporating relevant new evidence as it becomes available, and will provide accurate and up to date toxicity estimates to support clinical decision making. [Table: see text]

e13119 Background: Tyrosine kinase inhibitors (TKIs) are routinely used in the treatment of metastatic RCC and Sunitinib is approved for the use in adjuvant setting. Arterial thromboembolic events (ATEs) have been described with these agents, although the overall risk remains unclear. We did a systematic review and meta-analysis to determine the incidence associated with the use of FDA approved TKIs used in treatment of RCC. Methods: PubMed, EMBASE, Cochrane Central and Scopus databases were searched to identify phase 2 and 3 RCTs of TKI therapy in RCC. Trials were included if they reported ATEs defined as arterial thrombosis, cerebral ischemia or infarction, myocardial ischemia and myocardial infarction. The DerSimonian-Laird random effects meta-analysis was performed using CMAv3 software to derive pooled estimates of incidence rates of ATEs with its 95% confidence interval (CI). I2 statistic was computed to express the percentage of the total observed variability due to study heterogeneity. Risk for bias was assessed using the Cochrane Collaboration’s tool. Results: 1755 studies retrieved in the initial search, and 13 phase 2 and 3 clinical trials (n = 4983) were included in the quantitative analysis. The trials had open label design which can potentially result in bias. Risk of bias was low in all other domains. TKIs used for the treatment of RCC included sunitinib (n = 2632), sorafenib (n = 981), cabozantinib (n = 78), pazopanib (n = 844), axitinib (n = 189) and tivozanib (n = 259). The incidence of ATEs with the use of TKIs was 2.9% (95% CI: 2-3%). Cabozantinib was associated with the highest rate of ATEs (11.5%, 95% CI: 6-21%), followed by sunitinib (2.6%, 95% CI:2-3%) pazopanib (2.6%, 95% CI:2-4%) and axitinib (2.1%, 95% CI: 1-6%). The TKI with lowest event rate of ATE was tivozanib (0.8%, 95% CI:0.2-3%). Conclusions: The use of TKIs is associated with increased risk of developing ATEs. Clinicians should be aware of the possibility of increased ATEs and counsel the patients about this increased risk to enhance the process of informed decision making.

e13096 Background: Several studies have reported the association between atrial fibrillation (AF) and malignant cancer. Recently, results from a large cohort within the Women’s Health Study showed increased incident risk of breast, colon and lung cancer in patients with AF. Therefore, we performed a systematic review to assess the available evidence and a meta-analysis to define the strength of this association. Methods: MEDLINE, Cochrane and Scopus databases were searched for all prospective studies that reported the association between AF and presence of cancer. The HR for incident risk of common cancers was recorded (Breast, Lung, Colorectal) in patients with and without AF. Lung cancer was excluded because the data required for the analysis was not consistently reported. The DerSimonian-Laird random effects meta-analysis was performed to derive pooled Hazard Ratio (HR) estimates for incident risk of colorectal and breast cancer in patients with AF. Q-test was used to assess between-study heterogeneity; I2 statistic was computed to expresses the percentage of the total observed variability due to study heterogeneity. Results: A total of 390,479 participants in 3 prospective studies were included in the analysis. Mean age of participants was 66.3 ± 6.5 with mean follow up for 12.6 years. Patients with atrial fibrillation had 27% more risk of developing colorectal cancer [HR 1.27 (1.07-1.51) p < 0.005, I2= 73%] and 14% more risk of developing breast cancer [HR 1.14 (1.03-1.26) p = 0.01, I2= 37%] as compared to those without atrial fibrillation. Applying these hazard ratios to age adjusted yearly incidence ratios from 2000-2015, one in 5824 new onset AF cases will develop CRC and one in 7474 new onset AF cases will develop breast cancer. Conclusions: There is small but statistically significant increase in risk of subsequent diagnosis of colorectal or breast cancer diagnosis in patients with AF. Shared risk factors such as old age or systemic disease processes may explain this association. While the results of this analysis raise interesting questions for future search, these results should not be used as basis to initiate cancer screening for an occult cancer in a patient with AF.

e12545 Background: Palbociclib(P), Ribociclib(R) and Abemaciclib(A) in combination with Endocrine therapy (ET) have demonstrated progression free survival (PFS) in patients with metastatic hormone receptor positive, HER2-negative breast cancer as compared to ET alone. In the absence of head to head clinical trials and to provide clinical guidance, we performed an indirect comparison for P, R and A using network Meta-Analysis (NMA). Methods: MEDLINE, EMBASE and the Cochrane Library were searched to identify RCTs comparing P+ET, R+ET, A+ ET vs ET alone. NMA for PFS and toxicity endpoints was conducted using a multivariate random-effects meta-regression, using a consistency model, as described by White and colleagues. We used a frequentist approach and provided a point estimate from the network and a 95% CI from the frequency distribution of the estimate. We also estimated the relative ranking of the different treatments for each outcome using the distribution of the ranking probabilities and the surface under the cumulative ranking curves (SUCRA). Risk of bias was assessed using Cochrane Collaboration tool. Results: 8 RCTs were identified including 4580 patients. Risk of bias was low. 5 RCTs tested CDK 4/6 inhibitors in endocrine naive and 2 in the refractory setting, while MONALESSA-3 included patients both with endocrine naive and endocrine resistant disease. In the endocrine naïve patients, PFS for P was similar when compared indirectly with R (HR, 0.95, 95% CI 0.67-1.35) or A (HR, 1.00, 95% CI 0.62-1.61). Similarly, indirect comparison between R vs A did not show any statistical significant (HR, 0.95, 95% CI 0.62-1.45). In endocrine refractory patients, P showed no difference when compared indirectly to A (HR 1.12, 95% CI 0.67-1.87) or R (HR 0.98, 95% CI 0.52-1.86). R vs A did not show any statistically significant PFS either (HR, 1.14, 95% CI 1.61-4.51). P was ranked first in terms of PFS in frontline setting (SUCRA of 70.5) while R ranked first in the refractory setting (SUCRA of 39.5). QT prolongation was reported for R only. P caused more neutropenia while A caused more fatigue, anemia and diarrhea, although the results were not statistically significant. Conclusions: The efficacy of using either palbociclib, ribociclib or abemaciclib in combination with ET was similar in terms of PFS in either endocrine naïve or resistant disease. Palbociclib causes more neutropenia, abemaciclib causes more fatigue, anemia and diarrhea while ribociclib causes QT prolongation.

e12057 Background: Several RCTs have evaluated a shorter duration of T ( < 12 months) with hopes of similar efficacy, reduced cardiotoxicity, cost and burden of treatment. Of the 5 major studies, PERSPHONE showed that 6 months was non-inferior compared to 12 months. However, four additional studies of shorter duration failed to demonstrate non-inferiority. Therefore, we performed an updated systematic review and a meta-analysis to assess the optimal duration of adjuvant T. Methods: MEDLINE, EMBASE, Cochrane, Scopus and conference proceedings were searched to identify RCTs comparing one year of adjuvant T with a shorter duration in early-stage HER2+ breast cancer. The DerSimonian-Laird random-effects Meta-Analysis was performed using CMAv3 software to derive pooled Hazard Ratio (HR) estimates for overall survival (OS, Disease-Free Survival (DFS) and Odds Ratio(OR) estimates of cardiac toxicity. Q-test was used to assess between-study heterogeneity; I2 statistic was computed to express the percentage of the total observed variability due to study heterogeneity. The risk for bias was assessed using the Cochrane Collaboration’s tool. Results: We screened 1772 citations and identified 5 studies(n = 11,377) for analysis. 5691 patients were randomized to 12 months of adjuvant T while 5686 were randomized to a shorter duration (3 studies evaluated 6 vs 12 months, 2 studies evaluated 9 weeks vs 12 months). OS (HR, 1.16, 95% CI 1.03-1.31, P= 0.015,I2 0.00, p= 0.837) and DFS (HR, 1.14, 95% CI 1.02-1.26 , P = 0.016,I2 14.90, p= 0.319) were significantly worse in patients receiving shorter duration T as compared to 12 months. Cardiotoxicity was significantly higher in the 12 month group vs shorter duration (OR, 2.10, 95% CI 1.58-2.80, p = 0.000 ,I2 51.182, p= 0.085). Grade 3/4 cardiac events and cardiac events leading to discontinuation of therapy were significantly higher in patients receiving 12 months (HR 2.06, 95% CI 1.60-2.63, P = 0.000, I2 3.967, p= 0.384). There was no significant heterogeneity among studies. Risk of bias was low. Conclusions: Twelve months of adjuvant T is associated with significantly better DFS and OS compared to a shorter duration. As such, 12 months should remain the standard of care for most patients. There is an unmet need to identify lower risk groups which might do well with from shorter duration of HER2-directed therapy.