Zhao, Yujie

e20540 Background: Mesothelioma is an aggressive malignancy with few approved treatment options. Rare malignancies are often seen in higher volume at academic centers which are considered equipped with better expertise. Outcomes of mesothelioma in the novel therapeutic era and impact of initial treatment at academic versus community centers have not been reported. Methods: Mesothelioma cases from 2004-2019 were collected from The National Cancer Database (NCDB). Epidemiologic factors including sex, age, income, education, insurance status and location were assessed as well as overall survival across academic and community centers. Overall survival (OS) was plotted by type of treatment facility, accounting for several factors available in NCDB. Results: A total of 30136 mesothelioma patients were included in the analysis. 13482 (44.7%) were treated in academic centers and 16654 (55.3%) were treated in community practice locations. A higher proportion of patients with comorbidity scores of 2 or higher were seen in the community setting as compared to the academic setting (12.2% vs 7.6%). The distribution of diagnostic stages was similar between academic and community settings (14.1% vs 14.5% Stage I; 28.5% vs 30.7% Stage IV). A higher number of patients received surgery (39.6% vs 21.3%), chemotherapy (59% vs 45.3%), and immunotherapy (5.2% vs 3.5%) when presenting to academic rather than community settings, respectively (p value < 0.001). OS for all patients was 1.093 years (range: 0-16.47 years) for those treated in an academic center and 0.66 years (95% CI: 0-16.690; p < 0.001) for those treated in the community. Conclusions: Data from NCDB database shows that treatment of mesothelioma at academic centers was associated with improved overall survival when compared to receiving treatment in the community despite seeing similar proportions of early and late-stage disease at presentation. Patients were more likely to receive treatment of any kind if presenting to academic centers.

e20535 Background: Malignant peritoneal mesothelioma (MPM) is a rare disease with about 600 new cases per million people diagnosed annually in the U.S. High incidence of germline mutations has been reported in MPM patients (pts) without asbestos exposure. However, the incidence rate of developing multiple primary cancers in this population is unknown. The aim of this study is to investigate the frequency of additional malignancies in MPM pts. Methods: Using the Mayo Clinic Cancer Registry, we identified 64 pts who were treated for MPM from January 2002-December 2022 with updated follow-up data until 01/15/2023. Electronic medical records were reviewed. Results: Among the patient cohort, 25 pts were male, and 39 pts were female. 14/64 (22%) pts were found to have at least one additional malignancy, including breast cancer (4/14, 29%), colon cancer (3/14, 21%), lymphoma (3/14, 21%), ovarian cancer (2/14, 14%), melanoma (2/14, 14%), anal squamous cell carcinoma (1/14, 7%), papillary thyroid cancer (1/14, 7%), Chronic lymphocytic leukemia (1/14, 7%), renal cell carcinoma (1/14, 7%), squamous cell carcinoma of tongue (1/14, 7%), hepatocellular carcinoma (1/14, 7%) and pituitary macroadenoma (1/14, 7%). 4/14 (29%) pts had more than one (2-4) non-MPM malignancies. The median age at diagnosis of MPM was 65 years (44-82). The median age at diagnosis of non-MPM malignancies was 66 years (18-81). Most of the patients (11/14) were diagnosed with non-MPM malignancy within 12 months of diagnosis of MPM. Most pts (11/14, 78%) were diagnosed with non-MPM malignancy first, among which 5 pts (45%) were found to have MPM on surveillance scans. Germline mutation information was not available except for 2 pts with known family history (FH) of Lynch syndrome and Li-Fraumeni syndrome. FH was available in 29 pts, out of which 28 pts had FH of cancer identified in first-degree relatives. Among the 14 pts with additional malignancies, 9 pts had FH of cancer in first-degree relatives. Among all pts, 15 (18%) pts had a history of asbestos exposure. Among pts who also had non-MPM malignancies, 3/14 (21%) pts had a history of asbestos exposure. Among the 21 non-MPM cancers, 1/21 (5%), 11/21(52%), 1/21(5%), 3/21(14%), and 5/21(24%) non-MPM malignancies were stage 0, stage I, II, and III, or unknown at the diagnosis respectively. All except 1 pt underwent curative treatment for their non-MPM malignancies, and 12 pts had no evidence of disease at death or the time of last follow-up. Conclusions: The rate of multiple primary malignancies in pts with MPM is high, indicating possible genetic predisposition associated with this disease. Early genetic consultation and evaluation for germline mutations may need to be considered for these pts to improve long-term outcomes.

2529 Background: Tumor expression of the antiphagocytic protein CD47 (integrin associated protein) may lead to immunotherapy resistance (IO-R). PF-07257876 is a novel, IgG1, Fc-active, bispecific antibody targeting CD47 and PD-L1 designed to reverse IO-R, decrease anemia risk, and eliminate a priming dose. We report a Phase 1 dose escalation study (NCT04881045) in patients (pts) with advanced solid tumors, both IO-refractory and IO-naïve. Methods: The study enrolled pts ≥18 yrs with advanced non–small-cell lung carcinoma (NSCLC) and squamous cell carcinoma of the head and neck (SCCHN) with PD-L1 expression >1% post anti-PD-1/PD-L1 therapy. Pts with other PD-L1+ tumors known to express CD47 were included (prior IO not required). Pts received PF-07257876 at escalating dose levels in 28-day cycles. Primary objectives were safety (dose-limiting toxicity [DLT] rate), tolerability, and determination of Recommended Phase 2 Dose (RP2D). Secondary and exploratory objectives included pharmacokinetics (PK), blood receptor occupancy (RO), CD47 levels by immunohistochemistry (IHC), tissue biopsy findings, and objective response rate (ORR) per RECIST v.1.1. Results: As of 20OCT2022, 18 pts were enrolled (NSCLC: n = 6; SCCHN: n = 4; other: n = 8). Median (range) age 68 (46–79) yrs. PF-07257876 was given at ascending doses, 150-2400 mg by subcutaneous (SC) injection or SC infusion every 2 weeks. 16 (89%) pts had treatment-related adverse events (TRAEs): Grades 1/2: n = 12 (67%); Grade 3: n = 1 (6%); Grade 4: n = 3 (17%); no Grade 5. Most common TRAEs: injection site reaction/erythema (n = 13, 72%), thrombocytopenia (n = 6, 33%), anemia (n = 5, 28%), and nausea (n = 4, 22%). DLTs occurred in 2 of 3 pts at the highest tested dose (Grade 4 neutropenia and thrombocytopenia, n = 1; Grade 4 thrombocytopenia, n = 1; both pts recovered). One pt with IO-R SCCHN had a confirmed partial response (duration of response 16 wks). ORR was 5.6% (1/18). Drug exposure increase after 1st dose was not dose proportional. Blood RO was > 95% for PD-L1 and > 70% for CD47 with drug exposure. All pts’ baseline CD47 IHC levels were moderate to high. Pharmacodynamics cytokine profiling showed notable dose-response increases of IFNg, TNFa, CXCL9/10, CCL3/4, without IL-6 increase. Conclusions: PF-07257876 was well tolerated with manageable toxicity. Incidence and grade of anemia or thrombocytopenia were manageable. Target engagement of CD47 and PD-L1 in peripheral blood was high. Innate and adaptive cytokine modulation was observed. Antitumor activity was modest. Expansion is ongoing at 1800 mg. Clinical trial information: NCT04881045 .

Lung cancer remains the leading cause of cancer-related mortality worldwide. Non-small-cell lung cancer (NSCLC) is the most common type and is still incurable for most patients at the advanced stage. Targeted therapy is an effective treatment that has significantly improved survival in NSCLC patients with actionable mutations. However, therapy resistance occurs widely among patients leading to disease progression. In addition, many oncogenic driver mutations in NSCLC still lack targeted agents. New drugs are being developed and tested in clinical trials to overcome these challenges. This review aims to summarize emerging targeted therapy that have been conducted or initiated through first-in-human clinical trials in the past year.

Abstract Non‐small cell lung cancer patients with anaplastic lymphoma kinase or c‐ros oncogene 1 mutations who are treated with the tyrosine kinase inhibitor crizotinib rarely develop crizotinib‐associated renal cysts (CARCs). Here, we present a case report and review of the literature supporting the hypothesis that CARCs may correlate positively with progression‐free survival.

With the advent of targeted therapy for non-small-cell lung cancer, there are many new available treatment options for patients whose cancer harbors an actionable mutation or alteration. These new medications come with numerous side effects, for some of which, the management is not well defined. Alectinib is a second-generation tyrosine kinase inhibitor approved for stage-IV lung adenocarcinoma with anaplastic lymphoma kinase gene rearrangement. Severe (⩾Grade 3) skin rash is a rare side effect of alectinib. Reintroducing alectinib in patients with severe skin rash is not well defined in the medical literature. While other case reports have outlined their approach and desensitization protocol, the maximum dose that patients were titrated up to in a desensitization protocol was 300 mg twice daily. Here, we report a case of Grade 3 skin rash secondary to alectinib, and our experience in managing the rash and reintroducing alectinib with a unique desensitization protocol to a max of 600 mg twice daily (full dose). This case could provide further guidance to oncologists managing patients with this adverse event and may aid in reducing concerns to both patients and physicians about recurrence of skin rash at the maximum dose.

9543 Background: Lung cancer is the leading cause of cancer related death in the United States in all racial groups. However, the overall death rate from lung cancer is different among white, black and Asian. Although differences in socioeconomic status and treatments received might be the contributing factors, the biology, particularly genomic alteration of cancer might also have an important impact. To date, the differences of genomic alterations among all racial patients are poorly understood. Methods: The American Association for Cancer Research (AACR) Project Genomics Evidence Neoplasia Information Exchange (GENIE, version 7.0) database was analyzed. A total of 8908 patients with lung adenocarcinoma (LUAD) were identified. Among them, 5652 patients who had comprehensive sequencing results (gene panel ≥ 275) were selected for further analysis. Patients with unknown race, undefined and Pacific Island (only 3 patients) were excluded. Finally, 5360 patients were included in the study. The prevalence and distribution of genomic alteration cross all racial groups were analyzed. Results: Overall 5951 samples from 5360 patients were collected (85.7% white, 7.9% Asian, 4.7% black, 0.2% Native American and 1.4% other). Most patients have only one sample. The median mutation counts in white, black, Asian, Native American and others are 7, 6, 5, 5, 7 respectively (Kruskal–Wallis test, P< 0.001). Asian have significantly higher rates of insertion and deletions than other races (14.8% of Asian versus 9.8% of white, 10.7% of black, 10.4% of Native American, 11.1% of other; Pearson’s chi-square test, < 0.001). TP53, EGFR, KRAS and STK11 are the most frequent alterations in white, black and other. EGFR, TP53, KRAS and APC are the most frequent alterations in Asian. STK11 mutations are rare in both Asian and Native American. Native Americans have more alterations of LRP1B, ARID2 and ATM, although the patients’ number remains small. ATM and KEAP1 mutations are also common in white and black. EGFR is the highest discrepancy gene in racial distribution. 78.9% Asian, 47.7% black, 36.4% of native American had EGFR alteration in comparison to 29.6% in white (Fisher's exact test, P < 0.001). KRAS is the second highest discrepancy gene in racial distribution. 11.6% Asian, 26.3% black, 27.3% of Native American had KRAS alteration in comparison to 36.1% in white (Fisher's exact test, P< 0.001). Conclusions: Our study demonstrated the potential diversity of genomic alterations across all racial groups with potential impact on therapeutic decisions.