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Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resultant clinical presentation, coronavirus disease 2019 (COVID-19), is an emergent cause of mortality worldwide. Cardiac complications secondary to this infection are common; however, the underlying mechanisms of such remain unclear. A detailed cardiac evaluation of a series of individuals with COVID-19 undergoing postmortem evaluation is provided, with 4 aims: (1) describe the pathological spectrum of the myocardium; (2) compare with an alternate viral illness; (3) investigate angiotensin-converting enzyme 2 expression; and (4) provide the first description of the cardiac findings in patients with cleared infection. Methods: Study cases were identified from institutional files and included COVID-19 (n=15: 12 active, 3 cleared), influenza A/B (n=6), and nonvirally mediated deaths (n=6). Salient information was abstracted from the medical record. Light microscopic findings were recorded. An angiotensin-converting enzyme 2 immunohistochemical H-score was compared across cases. Viral detection encompassed SARS-CoV-2 immunohistochemistry, ultrastructural examination, and droplet digital polymerase chain reaction. Results: Male sex was more common in the COVID-19 group ( P =0.05). Nonocclusive fibrin microthrombi (without ischemic injury) were identified in 16 cases (12 COVID-19, 2 influenza, and 2 controls) and were more common in the active COVID-19 cohort ( P =0.006). Four active COVID-19 cases showed focal myocarditis, whereas 1 case of cleared COVID-19 showed extensive disease. Arteriolar angiotensin-converting enzyme 2 endothelial expression was lower in COVID-19 cases than in controls ( P =0.004). Angiotensin-converting enzyme 2 myocardial expression did not differ by disease category, sex, age, or number of patient comorbidities ( P =0.69, P =1.00, P =0.46, P =0.65, respectively). SARS-CoV-2 immunohistochemistry showed nonspecific staining, whereas ultrastructural examination and droplet digital polymerase chain reaction were negative for viral presence. Four patients (26.7%) with COVID-19 had underlying cardiac amyloidosis. Cases with cleared infection had variable presentations. Conclusions: This detailed histopathologic, immunohistochemical, ultrastructural, and molecular cardiac series showed no definitive evidence of direct myocardial infection. COVID-19 cases frequently have cardiac fibrin microthrombi, without universal acute ischemic injury. Moreover, myocarditis is present in 33.3% of patients with active and cleared COVID-19 but is usually limited in extent. Histological features of resolved infection are variable. Cardiac amyloidosis may be an additional risk factor for severe disease.

Context.— Respiratory failure appears to be the ultimate mechanism of death in most patients with severe coronavirus disease 2019 (COVID-19) infection. Studies of postmortem COVID-19 lungs largely report diffuse alveolar damage and capillary fibrin thrombi, but we have also observed other patterns. Objective.— To report demographic and radiographic features along with macroscopic, microscopic, and microbiologic postmortem lung findings in patients with COVID-19 infections. Design.— Patients with confirmed COVID-19 infection and postmortem examination (March 2020–May 2020) were included. Clinical findings were abstracted from medical records. Lungs were microscopically reviewed independently by 4 thoracic pathologists. Imaging studies were reviewed by a thoracic radiologist. Results.— Eight patients (7 men, 87.5%; median age, 79 years; range, 69–96 years) died within a median of 17 days (range, 6–100 days) from onset of symptoms. The median lung weight was 1220 g (range, 960–1760 g); consolidations were found in 5 patients (62.5%) and gross thromboemboli were noted in 1 patient (12.5%). Histologically, all patients had acute bronchopneumonia; 6 patients (75%) also had diffuse alveolar damage. Two patients (25%) had aspiration pneumonia in addition. Thromboemboli, usually scattered and rare, were identified in 5 patients (62.5%) in small vessels and in 2 of these patients also in pulmonary arteries. Four patients (50%) had perivascular chronic inflammation. Postmortem bacterial lung cultures were positive in 4 patients (50%). Imaging studies (available in 4 patients) were typical (n = 2, 50%), indeterminate (n = 1, 25%), or negative (n = 1, 25%) for COVID-19 infection. Conclusions.— Our study shows that patients infected with COVID-19 not only have diffuse alveolar damage but also commonly have acute bronchopneumonia and aspiration pneumonia. These findings are important for management of these patients.

Abstract Aims Coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been associated with cardiovascular features of myocardial involvement including elevated serum troponin levels and acute heart failure with reduced ejection fraction. The cardiac pathological changes in these patients with COVID-19 have yet to be well described. Methods and results In an international multicentre study, cardiac tissue from the autopsies of 21 consecutive COVID-19 patients was assessed by cardiovascular pathologists. The presence of myocarditis, as defined by the presence of multiple foci of inflammation with associated myocyte injury, was determined, and the inflammatory cell composition analysed by immunohistochemistry. Other forms of acute myocyte injury and inflammation were also described, as well as coronary artery, endocardium, and pericardium involvement. Lymphocytic myocarditis was present in 3 (14%) of the cases. In two of these cases, the T lymphocytes were CD4 predominant and in one case the T lymphocytes were CD8 predominant. Increased interstitial macrophage infiltration was present in 18 (86%) of the cases. A mild pericarditis was present in four cases. Acute myocyte injury in the right ventricle, most probably due to strain/overload, was present in four cases. There was a non-significant trend toward higher serum troponin levels in the patients with myocarditis compared with those without myocarditis. Disrupted coronary artery plaques, coronary artery aneurysms, and large pulmonary emboli were not identified. Conclusions In SARS-CoV-2 there are increased interstitial macrophages in a majority of the cases and multifocal lymphocytic myocarditis in a small fraction of the cases. Other forms of myocardial injury are also present in these patients. The macrophage infiltration may reflect underlying diseases rather than COVID-19.

Context.— Distinguishing pulmonary sarcomatoid carcinoma from pleural sarcomatoid mesothelioma is challenging because of overlapping histology, immunophenotype, and clinical features. Reliable immunohistochemical markers to aid in this distinction would be very valuable. Recent studies have proposed that MUC4 expression is common in sarcomatoid carcinoma but not in sarcomatoid mesothelioma, with the converse pattern reported for GATA3. Objective.— To further explore the utility of MUC4 and GATA3 in distinguishing pulmonary sarcomatoid carcinoma from sarcomatoid mesothelioma. Design.— Well-characterized cases of sarcomatoid carcinoma (n = 32) and sarcomatoid mesothelioma (n = 64) were included. Diagnoses were confirmed by thoracic pathologists with incorporation of immunophenotype, clinical, and radiographic features. Whole-tissue sections were stained for GATA3 and MUC4. Results.— Patients with sarcomatoid carcinoma and sarcomatoid mesothelioma had similar mean age and male predominance. GATA3 was positive in 63 of 64 sarcomatoid mesotheliomas (98%; 42 diffuse, 16 patchy, 5 focal), and 15 of 32 sarcomatoid carcinomas (47%; 3 diffuse, 8 patchy, 4 focal). MUC4 was positive in 2 of 64 sarcomatoid mesotheliomas (3%; 1 patchy, 1 focal), and in 12 of 32 sarcomatoid carcinomas (38%; 5 diffuse, 6 patchy, 1 focal). Conclusions.— Diffuse GATA3 expression favors sarcomatoid mesothelioma over sarcomatoid carcinoma, which rarely shows diffuse expression (sensitivity and specificity of diffuse staining 66% and 94%, respectively). Focal and patchy GATA3 expression is observed in both tumor types, and therefore is not helpful in this distinction. Sensitivity of MUC4 for sarcomatoid carcinoma was low in our cohort, positive in only 38% with frequent patchy staining, but it was quite specific.

Context.— Autopsy rates have decreased dramatically despite providing important clinical information to medical practices and social benefits to decedents' families. Objective.— To assess the impact of an institutional Office of Decedent Affairs (ODA), a direct communication link between pathology and decedents' families, on hospital autopsy consent rates, autopsy-related communication, practitioner views, and next-of-kin experiences. Design.— A before and after study involving all hospital decedents whose deaths did not fall within the jurisdiction of the medical examiner's office from 2013 to 2018. A pathology-run ODA launched in May 2016 to guide next-of-kin through the hospital death process (including autopsy-related decisions) and serve as the next-of-kin's contact for any subsequent autopsy-related communication. Critical care and hematology/oncology practitioners were assessed for their autopsy-related views and decedents' next-of-kin were assessed for their autopsy-related experiences. Autopsy consent rates for non–medical examiner hospital deaths, autopsy-related communication rates, practitioner views on the role and value of autopsy, and next-of-kin autopsy experiences and decisions factors were compared prior to and after ODA launch. Results.— Autopsy consent rates significantly increased from 13.2% to 17.3% (480 of 3647 deaths versus 544 of 3148 deaths; P < .001). There were significant increases in the rate of autopsy-related discussions and bereavement counseling provided to decedents' families. Practitioner views on the positive role of autopsy for any hospital death and those with advanced stage cancer also significantly increased. Next-of-kin indicated more consistent autopsy-related discussions with the potential benefits of autopsy discussed becoming key decision factors. Conclusions.— An ODA improves hospital autopsy consent rates, autopsy-related communication, providers' autopsy-related views, and next-of-kins autopsy experiences.

e19013 Background: Mutation profiling to assess for potentially druggable mutations in NSCLC is being offered at an increasing number of cancer centers throughout North America and internationally. Although data continue to accumulate for the potential value of mutation testing in designing chemotherapeutic regimens, the treatment impact of obtaining information beyond assessment of EGFR and ALK status remains unclear. How best to obtain and clinically utilize these data, including information from exome and whole genome sequencing, also remains unclear. Methods: Patients were reviewed electronically in a multidisciplinary conference regarding indications for testing and results of mutation profiling from various methods, including the mass-spec based LungCarta test, targeted NexGen sequencing, exome, and whole genome sequencing. Outcomes of the multidisciplinary review were communicated back to treating physicians. Results: Mutation testing was performed on 200 patients using a variety of approaches. The majority (>150) were surgically resected stage I and II tumors. Mutations in at least 1 major cancer driver gene, including EGFR, KRAS, MET, BRAF and PIK3CA, were found in 47% of all patients tested. EGFR mutations were present in 14.8% of patients tested, KRAS 21.3%, BRAF 2.6%, PIK3CA 3.2%, and MET 4.5%. A total of 8 patients underwent either exome or whole genome sequencing. A limited number of patients (<10) had mutation results that impacted treatment decisions from this cohort. Conclusions: Mutation profiling can influence treatment decisions in NSCLC, but at a low frequency. The role of exome and or whole genome sequencing for patients with NSCLC is evolving and remains undefined.

11119 Background: Evaluation of prognostic factors in carcinoid tumors of the lung is limited due to the rarity of disease. This study assessed Ki-67 expression and other clinical variables as prognostic factors in 262 patients. Methods: A systematic search of Mayo Clinic lung cancer epidemiology and tumor registry databases from 1997 to 2009 identified 449 consecutive patients, with 262 having available tissue blocks [40 atypical carcinoids (AC) and 222 typical carcinoids (TC)]. Clinical data were collected by chart review. Tissue blocks were reviewed by 1/3 pathologists using WHO criteria. Tumors were tested for the Ki-67 index using digital image analysis (tumor tracing) by two operators. The association and predictive value of the factors with recurrence-free and overall survival (RFS and OS) were explored using univariable Cox proportional Hazards model and concordance (c) index. Results: Age, stage, smoking history, lymph node (LN) involvement and Ki-67 index were significant prognostic factors for RFS and OS. Median follow-up on alive-patients is 5 years (range: 0.006-5). Median percentage of Ki-67 index of AC and TC were 1.61% and 0.56% (P<0.0001), respectively. Patients with Ki-67 ≥ 1% had significantly worse RFS (HR=3.69, P<0.0001) and OS (HR=3.69, P=0.0007) compared with Ki-67 < 1% group. The c-index of Ki-67 (0.65) was comparable to the pathologic distinction between AC and TC (0.62 for original diagnosis and 0.63 for central-reviewed diagnosis). Conclusions: Ki-67 index cutoff value of 1% is a valuable prognostic biomarker for pulmonary carcinoids based on this large cohort. Our data also provide strong evidence for clinical variables such as age, stage, smoking history, and LN involvement as clinical prognostic factors in pulmonary carcinoids. A prognostic calculator incorporating Ki-67 and clinical variables is under development. [Table: see text]

7568 Background: The molecular events in the initiation and progression of invasive lung adenocarcinoma remain poorly characterized. These tumors are thought to develop through an adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), invasive adenocarcinoma (AD) sequence. The goal of our study was to assess lineage relationships between in situ and invasive components within adenocarcinomas with prominent lepidic growth patterns. Methods: Frozen tissue from fourteen lung adenocarcinomas with mixtures of AD together with an adjacent in situ component (AIS), varying in ratio between 40 to 80%, were selected from our Lung Specimen Registry. Laser capture microdissection (LCM) of each component was performed separately for each tumor. Genomic DNA was isolated using a direct in situ whole genome amplification (WGA) methodology, and Next Generation Sequencing performed using an Illumina Mate Pair (MP) library protocol. MP sequence reads were mapped to the human genome and primers spanning the fusion junctions were used in validation PCRs. Results: Genomic break points identical and unique to a specific patient were identified between the AIS and AD components in 13 (of 14) cases. The total number of events per case ranged from 4-215, and the number of identical events shared between the AIS and AD components ranged from 30 to 90%. Recurrent genomic breakpoints between cases were also observed, with the 2 most common involving 8q24.3 in 5 cases and FAM19A2 on chromosome 12 in 4 cases. PCR validation of selected genomic alterations confirmed the genomic break points identified from sequencing in both the AIS and AD in all cases. Interestingly, we also observed a limited number of genomic alterations present in a zonal distribution of surrounding normal lung around the tumor mass. Conclusions: Our study demonstrates unique chromosomal alterations present in both the AIS and AD components of individual lung tumors with features of lepidic growth. These data provide evidence for lineage relationship and clonal relatedness between the two components, and provide genomic evidence for a model of stepwise progression from AIS to invasive AD in this subset of lung adenocarcinomas.

7509 Background: NTX-010 is a naturally occurring replication-competent picornavirus with potent and selective tropism for SCLC tumor cells expressing neuroendocrine markers. A phase I study of NTX-010 showed evidence of antitumor activity in patients with SCLC. Methods: ES-SCLC patients (pts) with SD, PR or CR after at least 4 cycles of platinum-based chemotherapy were pre-registered to confirm diagnosis of SCLC with > 1 neuroendocrine marker by a central pathology review. Eligible pts were.randomized 1:1 to placebo (B) or NTX-010 (A). NTX-010 or placebo was administered intravenously as a 1-hour infusion in 100 mL normal saline as a single dose of 1 x1011vp/kg. Viral studies to determine distribution, clearance of the virus and the presence of neutralizing antibodies were done. The primary goal of this trial was to compare the progression-free survival (PFS) of arm A to B based on a sample size of 45 patients per arm to detect an improvement in median PFS from 3 to 5 months (m). A pre-planned interim futility analysis was done after 40 PFS events, and reported here. Results: The trial is permanently closed to accrual. One-hundred and twenty pts were pre-registered, of whom 58 were randomized. Baseline age, gender, ECOG performance status, and histology were balanced between arms. Median age was 63 (range: 44 - 82). 31% of pts had a PS of 0 and 69% of 1. Grade 4 adverse events were seen in 3 (12.5%) patients in arm A and none in arm B. Based on the interim futility analysis, PFS was 1.7 m (95% CI: 1.3-3.1) for arm A and 1.7 m (95% CI: 1.4-4.3) for arm B. Pts with viral RNA at 7 (7 pts) and 14 (6 pts) days had worse PFS compared to those with no detectable levels within arm A (1.0 vs 1.6 m, p=0.02; 0.9 vs. 1.2 m, p=0.06). Median follow-up in pts is 6.1 m. The 3-month OS estimates are 83% (95% CI: 69%-100%) and 85% (70%-100%) for arms A and B respectively. Conclusions: This phase II study showed no benefit in PFS for ES-SCLC patients receiving NTX-010. Pts with detectable virus at 7 and 14 days had worse PFS. Clinical trial information: NCT01017601.

1071 Background: N0234 is a phase II trial of gemcitabine at 1000 mg/m2 days 1 and 8 of a 21 day cycle and erlotinib at 150 mg daily in patients with previous therapy with either an anthracycline or a taxane for MBC. A partial response (PR) rate of 17% has been reported (ASCO 2005). Recent information suggests that over-expression of the EGFR pathway is frequent in patients with TNeg MBC. Methods: Tissue and serum were obtained for translational studies of ER, PR, HER2, and proteins related to EGFR pathway on tissue using immunohistochemistry; CK19, mammoglobin, and TTK on circulating tumor cells (CTCs). Markers were evaluated centrally, blinded to patient outcome. Complete data were available in 57 of 59 eligible patients; 20/57 patients (pts) were TNeg. Results: A PR rate of 25% and clinical benefit rate (PR + stable disease > 6 months)of 25% was observed in TNeg pts as compared to a PR rate of 14% (p = 0.30) and clinical benefit rate 22% (p= 0.75) for non-TNeg pts. Median progression free survival 72 days vs 98 days (p=0.13) and overall survival 227 days vs 738 days (p<0.001) were shorter for TNeg pts. Translational results for the EGFR pathway proteins and CTC analysis is forthcoming. Conclusions: The combination of gemcitabine and erlotinib appears to be as active in the non-TNeg and TNeg subset of patients on this trial. TNeg patients had an inferior clinical result, confirming the poor outcome seen in these patients. Data for the remaining biomarkers potentially predictive of activity will be presented. Supported by CA-25224, CA-37404. [Table: see text]