Citations

9135 Background: Bronchial carcinoid (BC) is often categorized into multifocal (MBC) or solitary (SBC). MBC, excluding tumorlet and diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, is considered a relatively uncommon subgroup of BC, with much of the MBC literature stemming from case reports/small series. Our study analyzes MBC among a large cohort of 569 patients with BC and argues for change to the current clinical understanding of MBC. We suggest using the term bronchial neuroendocrine tumor (bNET) to more accurately represent its cells of origin and move away from “carcinoid” (historically meaning “carcinoma-like”) and the outdated associated connotation that carcinoids all have a similar, benign clinical and biological behavior. Methods: Using the Mayo Clinic Epidemiology and Genetics of Lung Cancer Database with Institutional Review Board approval, we retrospectively reviewed 569 patients with bNET (204 males, 365 females) presenting to Mayo Clinic Rochester between 1/1997-12/2012. We used univariate and multivariate Cox regression analyses to evaluate factors affecting overall survival. Results: 80 patients (of 569, 14.1%) were diagnosed with multifocal (MbNET) and 489 with solitary (SbNET). Two-sided Fisher’s exact tests found that older age, female gender, never having smoked cigarettes, and tumorlets were associated with MbNET diagnosis. Family lung cancer history, histopathologic grading (pathology: typical vs. atypical), Ki67, and presence of syndromes (carcinoid, Cushing, and MEN1 syndromes) were similar between MbNET and SbNET groups. Most MbNET cases were stage III-IV at the time of diagnosis, while the majority of SbNET cases were stage I. 5-year OS (83%) and 5-year PFS (75%) of MbNET patients were higher than those of their SbNET counterparts (74% and 68%, respectively). Metastasis status was an independent prognostic factor of poor OS in SbNET (P<0.001) but not in MbNET (P=0.71)(Table). Conclusions: Clinical, radiologic, and histopathologic characteristics and prognostic factors differed between SbNET and MbNET. MbNET arose as a new entity often with advanced stage disease, but good prognosis, which does not follow the NSCLC TNM staging system as in the 2009 NCCN guidelines (used during this study) or the updated 2021 NCCN guidelines which continue to stage lung carcinoid similarly to NSCLC. It may be beneficial to consider multifocal lung carcinoid instead as multifocal bNET, a new clinical entity, warranting a novel staging approach that more accurately reflects prognosis.[Table: see text]

e19526 Background: Zanubrutinib is an oral, highly selective, next-generation Bruton tyrosine kinase inhibitor. Efficacy of zanubrutinib was compared with bendamustine + rituximab (BR) in adult patients with treatment-naïve (TN) chronic lymphocytic leukemia (CLL) in the phase 3 SEQUOIA trial (NCT03336333). However, efficacy of zanubrutinib compared with other frontline CLL treatments remains unknown. The goal of this network meta-analysis of randomized controlled trials (RCTs) was to estimate the relative efficacy of zanubrutinib compared with standard frontline treatments for CLL. Methods: A total of 4 relevant RCTs were identified by a targeted literature review conducted throughout January 2022, CLL11 (NCT01010061), ALLIANCE (NCT01886872), MABLE (NCT01056510), and SEQUOIA. A feasibility assessment was performed to ensure that RCTs included within each population strata did not differ with respect to effect modifiers including presence of mutation, age, del11, and del17 status. A network was constructed for the composed 4 RCTs to compare the efficacy of zanubrutinib with bendamustine + rituximab, chlorambucil + obinutuzumab, chlorambucil + rituximab, and ibrutinib in patients with previously untreated CLL. Bayesian NMA models were conducted to simultaneously synthesize hazard ratio (HR) and 95% credible intervals (CI) for investigator-assessed progression-free survival (PFS). A constant hazard ratio was assumed in the NMA analysis. Statistical analyses were performed using codes suggested by the National Institute for Health and Care Excellence. Results: The efficacy results of the NMA indicated a statistically significant improvement in PFS for zanubrutinib over bendamustine + rituximab (HR=0.42; [95% CI=0.27, 0.65]), chlorambucil + obinutuzumab (0.45 [0.23, 0.86]), and chlorambucil + rituximab (0.22 [0.12, 0.41]). Zanubrutinib achieved comparable PFS to ibrutinib (1.07 [0.59, 1.94]). Conclusions: This is the first NMA to compare the efficacy of zanubrutinib with all commonly utilized first-line treatment for TN CLL. Results from this indirect treatment comparison suggested that the PFS for zanubrutinib may be statistically significantly better than immunochemotherapy. Findings from this study require validation with further large scale RCTs with longer follow up time.[Table: see text]

e19514 Background: Zanubrutinib, a next-generation Bruton’s tyrosine kinase inhibitor (BTKi), demonstrated superior overall response rate and a trend toward improved progression-free survival (PFS) as compared to ibrutinib in patients with relapsed or refractory (R/R) chronic lymphocytic leukemia (CLL) in the phase 3 ALPINE trial (NCT03734016) based on interim analysis. However, its comparative efficacy with other treatments is not known. The goal of this study was to estimate the relative efficacy of zanubrutinib compared with standard treatments for R/R CLL through a network meta-analysis (NMA). Methods: The efficacy of zanubrutinib from ALPINE (study of zanubrutinib and ibrutinib in patients with R/R CLL was compared to ibrutinib, acalabrutinib, bendamustine and rituximab (BR), and venetoclax + rituximab (V+R) using data from 4 RCTs. Relevant RCTs were identified using a systematic literature review. A network was constructed that composed RCTs (ALPINE, ELEVATE-RR [NCT02477696], ASCEND [NCT02970318], and MURANO [NCT02005471]). Bayesian network meta-analysis (NMA) models were used to simultaneously synthesize hazard ratios (HRs) and 95% credible intervals (CrIs) for investigator-assessed PFS and overall survival (OS) to estimate the relative efficacy of zanubrutinib versus comparators of interest. An assumption of constant hazard ratio was applied in the NMA analysis. Analyses were performed using well-established codes published by the National Institute for Health and Care Excellence (NICE) Decision Support Unit and were implemented with OpenBUGS (version 3.2.3). Results: The NMA suggested a significant improvement in PFS for zanubrutinib over acalabrutinib (HR=0.52, 95% CrI [0.30, 0.90]), ibrutinib (0.47, [0.29, 0.76]), and BR (0.13, [0.06, 0.26]). Zanubrutinib had a numerically better PFS than V+R (0.69, [0.32, 1.46]) while not reaching statistical significance. For OS, NMA results showed a trend favoring zanubrutinib over acalabrutinib (0.75, [0.35, 1.59]), ibrutinib (0.62, [0.31, 1.22]), and BR (0.52, [0.21, 1.24]). The difference was not statistically significant with wide CrIs, suggesting a high uncertainty as inherent limitation of the analysis. Conclusions: This NMA reports the first summary of comparative PFS of available treatments for R/R CLL. Indirect treatment comparisons suggest PFS on zanubrutinib may be superior to other BTKis and immunochemotherapies in R/R CLL patients.[Table: see text]

e18790 Background: Patients with SARS-CoV-2 with a diagnosis of cancer have increased risk of severe COVID-19 outcomes compared to patients without cancer. However, little is known regarding outcomes of patients with COVID-19 and cancer in the setting of human immunodeficiency virus (HIV). Given the unique risks of this population, we sought to understand COVID-19 outcomes using registry data. Methods: This is a descriptive research study utilizing the CCC19 registry, an international multi-institutional registry with healthcare provider-reported cases of patients with cancer and COVID-19. Between March 2020-December 2021, 116 persons with HIV (PWH) and 10,642 persons without HIV (PWOH) with laboratory-confirmed SARS-CoV-2 infection were identified as eligible for the analysis. Results: Median follow-up time for both groups was 90 days, with interquartile range (IQR) 30-180 days. Most PWH were actively receiving antiretroviral therapy (ART) at the time of COVID-19 diagnosis, with 71% (n = 82) having named drug information available; bictegravir/emtricitabine/tenofovir was the most common ART (n = 25). PWH were of younger age (median 57.5 yrs [IQR 46.5-63.25] vs 65 yrs [IQR 55-74]), male (81% vs 47%), and either non-Hispanic Black or Hispanic (71% vs 34%) compared to PWOH. 12% of PWH (n = 14) were current smokers compared to 6% of PWOH (n = 638), and more than half in each group were never smokers (51% of PWH and 53% of PWOH). The following comorbidities were identified in PWH vs PWOH: cardiovascular (16% vs 20%), pulmonary (16% vs 20%), renal (15% vs 14%), and diabetes mellitus (18% vs 27%). A higher proportion of PWH had hematologic malignancy compared to PWOH (33% vs 19%). More PWH had active cancer which was progressing at the time of SARS-CoV-2 infection compared to PWOH (24% vs 14%). 44% of PWH (n = 51) had received active systemic anticancer therapy within the 3 months preceding SARS-CoV-2 infection (including cytotoxic, targeted, endocrine therapies, and immunotherapy) compared to 51% of PWOH (n = 5,420). PWH had an increased rate of hospitalization (58% vs 55%) compared to PWOH. Although a lower proportion of PWH required supplemental oxygen during hospitalization compared to PWOH (34% vs 38%) and ICU admission rates were identical between the two groups (16% vs 16%), PWH had an increased rate of mechanical ventilation (14% vs 10%) and death (24% vs 18%) compared to PWOH. Conclusions: This is the first known study describing outcomes of patients with cancer and COVID-19 in the PWH population from a large multinational dataset. PWH have characteristics associated with adverse outcomes in prior analyses (male sex, non-Hispanic Black or Hispanic, hematologic malignancy, progressing cancer) but are notably younger and have fewer comorbidities. HIV infection may portend increased risk of severe COVID-19 and death; however, additional analyses, including multivariable regression, are warranted.

e18729 Background: While the incidence of AF in CLL has been increasing, the implications of AF in real-world CLL patients remain understudied. This study aimed to assess the impact of AF on clinical and economic outcomes in CLL patients. Methods: This retrospective observational study used the US IBM MarketScan® commercial claims/Medicare supplement database (2017-2020) to identify newly diagnosed CLL patients (≥18 years) and incidence of AF after index date, defined as the first CLL diagnosis date. Patients were followed for ≥3-months pre-index, and from index to last follow-up or death. In addition to patient characteristics, clinical outcomes (incidence of heart failure [HF], bleeding and stroke) and economic outcomes (costs and healthcare resource utilization [HRU]) were compared between CLL patients with AF (CLL+AF) and CLL patients without AF (CLL-AF). HRU was evaluated by inpatient, outpatient, ER, and pharmacy visits. Multivariable regression analyses were conducted to examine the association between AF and clinical outcomes. Results: Among a total of 16,800 newly diagnosed CLL patients included in the study, 20% developed AF. CLL+AF were significantly older than CLL-AF (median: 77 vs 62 years; P < .001). Compared to CLL-AF, CLL+AF also had significantly more comorbidities at baseline, as shown by higher Charlson comorbidity index (CCI) (median: 1.0 vs 3.0; P < .001) and more patients with previous AF history (0.3% vs 8.4%; P < .001). Further assessing clinical outcomes in CLL+AF vs CLL-AF, significantly higher incidence of HF (26.3% vs 3.0%; P < .001), bleeding (12.2% vs 4.8%; P < .001) and stroke (6.6% vs 1.2%; P < .001) were observed. For HRU, CLL+AF were reported to have significantly higher rates of ER visits (29.4% vs 12.9%; P < .001) and hospitalizations (42.2% vs 14.5%; P < .001) than CLL-AF. In CLL+AF, the average total AF-related costs were $13,520.21 within 30 days after AF diagnosis, and $22,304.82 within 60 days after AF diagnosis. Controlling for demographics and comorbidities, multivariable regressions reported statistically significant associations between AF and HF, as well as AF and stroke (Table). Conclusions: This real-world study reported significantly higher incidence of HF, bleeding and stroke incurred by CLL patients who developed AF compared with those who did not. The presence of HF, bleeding and stroke further increased HRU and costs. These findings highlight the importance of better disease management and treatment selection to prevent AF in CLL patients.[Table: see text]

3590 Background: Co-occurring alterations (COAs) in the HER2 and MAPK pathway are rare in mCRC. RAS, HER2 and BRAF alterations have been associated with resistance to EGFR inhibitor therapy (EGFR-mab). Typical co-occurring mutually exclusive gene mutations such as in KRAS and BRAF have been reported. This study aims to evaluate the prevalence of co-occurring alterations in the MAPK pathway or across MAPK/ HER2 and correlate to outcomes in patients with mCRC treated with EGFR-mab. Methods: This is a retrospective study of patients with mCRC within the Mayo Clinic database who have available blood-based NGS Guardant 360 data (September 2017-November 2021) and contained co-alterations in the MAPK pathway or across MAPK/ HER2. MSI-high cases were excluded. Typical-RAS was defined as alterations in codons 12, 13, 59, 61, 117, and 146 of KRAS, HRAS, and NRAS. Atypical-RAS alterations were considered mutations at other codons of these genes. Patient characteristics, specific mutations, and outcome data were assessed. Results: 692 patients (pts) with mCRC were identified and 66 (9.5%) of those had COAs detected. 59/66 pts had clinical data available. Median age was 52 years, 55.9% were male, and 61.0% had left-sided tumors. The frequency of detected alterations was: BRAF-V600E (7.3%), BRAF-non-V600E (7%), BRAF-amplification (3.04%), RAS-typical (39.5%), RAS-atypical (2.1%), HER2 amp (0.5%), HER2-mutation (1.2%) and PIK3CA (13%). COAs are described in the table. Twenty-three pts received EGFR-mab; COAs developed in 19 of them after progression on EGFR-mab. Four pts received EGFR-mab with documented COAs at baseline with none of them responding to treatment. Conclusions: COAs in MAPK and MAPK/ HER2 pathway are not uncommon in pts with mCRC emphasizing on the importance and feasibility of blood based NGS vs. selected gene testing. In pts with prior EGFR-mab treatment, COAs were detected after progression on treatment in the majority of pts, suggesting a mechanism of secondary treatment resistance. Further data including prospective validation is warranted. [Table: see text]

3586 Background: HSP90 mediated chaperoning is a well-conserved biological mechanism for stabilization and activation of kinases. More than 60% of human kinases including VEGFR, CRAF, CSF1R, and FGFR are target of HSP90 (client kinases), whereas EGFR is non-client. CDC37 is a specific co-chaperone determining selectivity of client kinases recognized by HSP90. We hypothesized that gene expression levels of CDC37 have predictive values for anti-angiogenic therapies in mCRC. Methods: The subjects of this study were mCRC patients treated with regorafenib (REGO, Japanese retrospective cohort) and those treated with bevacizumab (BEV) or cetuximab (CET) in combination with first-line chemotherapy (CALGB/SWOG 80405 trial cohort). CDC37 expression levels were measured using RNA isolated from FFPE samples by nCounter gene expression profiling (Nanostring) and HiSeq 2500 (Illumina) in the Japanese and CALGB/SWOG 80405 cohorts, respectively. Overall survival (OS) and progression-free survival (PFS) were compared between patients with high CDC37 expression ( CDC37-H) and those with low expression ( CDC37-L), grouped by median cutoff value in each cohort. Results: In total, 484 patients were included (50 treated with REGO, 227 treated with BEV, and 207 treated with CET). In REGO-treated patients, CDC37-H showed significantly better OS (median 11.3 vs 6.0 months, adjusted hazard ratio [HR] 0.24, 95% confidence interval [CI] 0.11-0.54, p <0.01) and PFS (median 3.5 vs 1.9 months, adjusted HR 0.51, 95% CI 0.28-0.94, p = 0.03) compared to CDC37-L. Similarly, in BEV-treated patients, CDC37-H showed significantly better PFS (median 13.5 vs 9.6 months, adjusted HR 0.59, 95% CI 0.43-0.79, p <0.01) and numerically better OS (median 34.1 vs 29.4 months, adjusted HR 0.81, 95% CI 0.60-1.11, p = 0.20) compared to CDC37-L. However, in CET-treated patients, CDC37-H and CDC37-L patients showed similar OS (median 33.7 vs 26.1 months, adjusted HR 1.00, 95% CI 0.73-1.38, p = 0.98) and PFS (median 11.3 vs 11.0 months, adjusted HR 1.08, 95% CI 0.81-1.45, p = 0.60). Significant interaction was observed between CDC37 expression and treatment in terms of PFS in the CALGB/SWOG 80405 cohort ( p = 0.01). Conclusions: Our results suggest patients with CDC37-dependent ( CDC37-H) tumors may derive more benefit from REGO and BEV both of which target HSP90 client kinases or signaling pathways, but not from CET which target HSP90 non-client kinase. Further validation studies are warranted to develop a novel personalized approach for targeted therapies based on CDC37 expression in mCRC patients. Support: U10CA180821, U10CA180888; Pfizer, Genentech; https://acknowledgments.alliancefound.org. ClinicalTrials.gov Identifier: NCT00265850.

3580 Background: Monoamine oxidases (MAOs), including MAOA and MAOB, are mitochondrial enzymes responsible for catalyzing monoamine oxidation. Increased expression of MAOs were found in several cancer types and high MAOB was associated with worse disease stage and poorer survival in CRC. Positive and negative correlations of MAOB expression with mesenchymal type and epithelial type gene expressions, respectively, have been reported. Hence, we investigated whether MAOB expression is predictive for targeted therapies in mCRC. Methods: 430 mCRC pts treated with either bevacizumab (BEV, n = 224) or cetuximab (CET, n = 206) in combination with first-line chemotherapy within the CALGB/SWOG 80405 trial were included in the analysis. MAOB RNA was isolated from FFPE tumor samples and sequenced on the HiSeq 2500 (Illumina). Overall survival (OS) and progression-free survival (PFS) were compared between groups of pts categorized by tertiles of MAOB expression into high (H), medium (M) and low (L). Hazard ratios (HR) and 95% confidence intervals (CI) were computed from multivariable Cox proportional hazards model, adjusting for age, sex, location, number of metastases, KRAS, MSI status, and treatment with FOLFOX or FOLFIRI. Sensitivity analyses were conducted after stratifying by sex. Logrank P-values describe differences without adjustment for patient characteristics. Results: In CET-treated pts, MAOB-L showed significantly longer OS (median 39.2 vs 30.9 vs 15.9 months, logrank P = 4.7E-05, L vs H (as reference) adjusted HR 0.42, 95% CI [0.27, 0.65]) and PFS (median 13.2 vs 11.8 vs 7.6 months, logrank P = 0.006, L vs H adjusted HR 0.59 [0.40, 0.88]) compared to MAOB-M and MAOB-H, respectively. Similar results were observed when evaluating MAOB expression as a continuous variable. In BEV-treated pts, no significant differences were observed when comparing MAOB expression tertiles; however, pts with lower MAOB expression had significantly better OS, but not PFS, when evaluating MAOB as a continuous variable (Cox LRT P = 0.015, covariate adjusted). In CET-treated pts, the effect of MAOB expression was observed in male but not female pts (OS: median 40.3 vs 30.9 vs 16.1 months by MAOB-L, M, H, respectively, logrank P = 6.8E-05, L vs H adjusted HR 0.33 [0.19, 0.59]; PFS: median 13.8 vs 12.6 vs 7.9 months, logrank P = 0.001, L vs H adjusted HR 0.46 [0.28, 0.79]). A significant interaction was observed between MAOB expression and treatment for OS ( P = 0.010) in males and females combined, but only in males ( P = 0.018) when stratified by sex. Conclusions: Our results suggest that pts with MAOB-L tumors may have greater benefit from CET-based treatment and that targeting MAOB may be a promising strategy to improve patient outcomes. Further validation studies are warranted to develop a novel personalized approach based on MAOB expression in mCRC pts. Clinical trial information: NCT00265850.

TPS1108 Background: The current first-line (1L) standard of care (SOC) for human epidermal growth factor receptor 2-positive (HER2+) metastatic breast cancer (MBC) is trastuzumab (T) plus pertuzumab (P) and a taxane. Despite advances in 1L SOC, most patients (pts) progress during maintenance therapy with T+P. Tucatinib is a tyrosine kinase inhibitor (TKI) approved in combination with T and capecitabine for adults with HER2+ MBC, with and without brain metastases (BM). In HER2CLIMB, the addition of tucatinib significantly prolonged progression-free survival (PFS) and overall survival (OS) in pts with HER2+ MBC and was well tolerated. Adding tucatinib also reduced the risk of disease progression or death in pts with untreated and/or active BM (Murthy et al. 2020, Curigliano et al. 2021). HER2CLIMB-05 investigates whether adding tucatinib to 1L SOC as maintenance therapy will extend PFS while maintaining quality of life (QOL). Methods: HER2CLIMB-05 (NCT05132582) is a phase 3, randomized, double-blind study evaluating tucatinib plus T+P as maintenance therapy for HER2+ MBC. Approximately 650 pts will be enrolled. Eligible pts will have advanced HER2+ disease, no progression on 4–8 cycles of prior 1L SOC, ECOG Performance Status of 0 or 1, and no or asymptomatic BM. Exclusion criteria include prior treatment with anti-HER2 and/or anti-epidermal growth factor receptor TKI (prior SOC for early BC is permitted) or inability to undergo contrast magnetic resonance imaging of the brain. Pts will be randomized 1:1 to receive either tucatinib or placebo twice daily, with T+P once every 21 days. Pts with HR+ disease may receive endocrine therapy. The primary endpoint is investigator-assessed PFS. Secondary endpoints include OS (key endpoint), time to deterioration of health-related QOL, central nervous system PFS, safety, and pharmacokinetic (PK) parameters. PFS and OS will be compared using a 2-sided stratified log-rank test between treatment groups. Time-to-event endpoints will be summarized using the Kaplan–Meier method. PK and safety data will be summarized using descriptive statistics. Enrollment is ongoing in the US, with additional sites planned. Clinical trial information: NCT05132582.

AbstractSeizure is one of the manifestations of central nervous system inflammatory demyelinating diseases, which mainly include multiple sclerosis (MS), aquaporin 4 antibody‐positive neuromyelitis optica spectrum disorder (AQP4‐NMOSD), and myelin oligodendrocyte glycoprotein antibody‐associated disease (MOGAD). Acute symptomatic seizures secondary to MS/AQP4‐NMOSD/MOGAD occur in the acute phase of the diseases, and are more frequent in MOGAD. In contrast, recurrent nonprovoked seizures, mainly attributed to autoimmune‐associated epilepsy, occur in the nonacute phase of the diseases. Seizures in MS/AQP4‐NMOSD/MOGAD mostly have a focal onset. MS patients with concomitant systemic infections, earlier onset, and greater disease activity are more likely to have seizures, whereas factors such as greater MS severity, the presence of status epilepticus, and cortical damage indicate a greater risk of developing epilepsy. In MOGAD, cerebral cortical encephalitis and acute disseminated encephalomyelitis (ADEM)‐like phenotypes (predominately ADEM and multiphasic disseminated encephalomyelitis) indicate a greater seizure risk. Multiple relapses with ADEM‐like phenotypes predict epilepsy in pediatrics with MOGAD. Pathophysiologically, acute symptomatic seizures in MS are associated with neuronal hyperexcitability secondary to inflammation and demyelination. Chronic epilepsy in MS is largely due to gliosis, neuronal dysfunction, and synaptic abnormalities. The mainstay of treatment for seizures secondary to MS/AQP4‐NMOSD/MOGAD consists of immunotherapy along with antiseizure medications. This critical review discusses the most‐updated evidence on epidemiology, clinical correlates, and inflammatory mechanisms underlying seizures and epilepsy in MS/AQP4‐NMOSD/MOGAD. Treatment cautions including drug‐drug interactions and the impact of treatments on the diseases are outlined. We also highlight pitfalls and challenges in managing such patients and future research perspectives to address unsolved questions.