BACKGROUND:The landscape of small cell lung cancer (SCLC) has changed since the 2019 and 2020 approvals of anti-PD-L1 atezolizumab and durvalumab for first-line (1L) treatment in combination with chemotherapy. We studied treatment patterns and real-world overall survival (rwOS) following 1L-3L therapy. PATIENTS AND METHODS:A nationwide electronic health record (EHR)-derived de-identified database was used to describe treatment patterns, characteristics, and survival of patients with extensive-stage (ES)-SCLC by 1L anti-PD-L1 treatment. Patients with ES-SCLC who initiated ≥1 line of systemic therapy from 2013 to 2021, with potential follow-up through 2022, were included. RESULTS:Among 9952 patients with SCLC, there were 4308 patients with ES-SCLC treated during the study period who met eligibility criteria. Etoposide + platinum (EP) chemotherapy was most common in the 1L, with addition of anti-PD-L1 therapy to most regimens by 2019. Second-line regimens varied by platinum sensitivity status and shifted from topotecan to lurbinectedin over time. Median rwOS following 1L therapy was 8.3 months (95% CI, 7.9-8.8) in those treated with 1L anti-PD-L1 and 8.0 months (95% CI, 7.8-8.2) in those who were not. Following 2L and 3L, median rwOS was 5.6 (95% CI, 4.9-6.3) and 4.9 months (95% CI, 3.4-6.0), respectively, among 1L anti-PD-L1-treated, and 4.5 (95% CI, 4.2-4.9) and 4.0 months (95% CI, 3.7-4.5), respectively, among those who were not. CONCLUSION:Despite the introduction of frontline anti-PD-L1 therapy, survival remains dismal among patients with ES-SCLC treated in the real-world setting.

Objective To describe standard of care and inform the evolving unmet need among extensive stage small-cell lung cancer (ES-SCLC) patients in Japan since approval of first-line anti-PD-L1 therapies, we describe treatment patterns and overall survival by line of therapy. Methods We conducted a descriptive analysis of adult ES-SCLC patients in Japan using de-identified patient data within the MDV database (hospital-based claims) to describe treatment patterns and DeSC database (payer-based claims linked to mortality of municipality records) to describe both treatment patterns and real-world overall survival (rwOS). Results The study population of MDV and DeSC cohorts included 6302 and 903 patients, respectively. First-line anti-PD-L1 therapy-based regimens grew since their approval in 2019 and were used in similar to 35% and similar to 59% of patients in 2022, in the MDV and DeSC cohorts, respectively. Amrubicin monotherapy was the most common second-line (2 L) regimen before and after 1 L anti-PD-L1 approvals. No clear standard of care was identified in third-line (3 L) and fourth-line (4 L). Median rwOS following 1 L therapy was 10.6 months (95% CI: 9.0, 11.8) and 9.3 months (95% CI: 8.3, 10.3) in patients who did and did not receive anti-PD-L1 therapy, respectively. Following 2 L, 3 L, and 4 L therapy, median rwOS was 6.7 months (95% CI: 5.9, 7.4), 5.5 months (95% CI: 4.4, 6.4), and 4.7 months (95% CI: 3.4, 6.9), respectively. Conclusions Anti-PD-L1 therapies have become part of first-line standard of care but survival in treated Japanese ES-SCLC patients remains poor, highlighting the unmet medical need in the post anti-PD-L1 era.

Patients diagnosed with cancer have an increased risk both for myelodysplastic syndromes (MDS) and for acute myeloid leukemia (AML) following treatment. Using SEER-Medicare data, we selected patients aged 66 years and older who completed systemic therapy between 2002 and 2014 for breast (stage I–III), lung (stage I–III), or prostate (stage I–IV) cancer. For each cancer, we estimated the risk of a composite endpoint of MDS or AML in patients receiving granulocyte colony-stimulating factor (G-CSF) vs. not. The 10-year cumulative risk difference (granulocyte colony-stimulating factor [G-CSF] − no G-CSF) for MDS-AML was 0.45% (95% CI 0.13–0.77%) in breast cancer and 0.39% (95% CI 0.15–0.62%) in lung cancer. G-CSF use was associated with a hazard ratio of 1.60 (95% CI 1.07–2.40) in breast cancer and 1.50 (95% CI 0.99–2.29) in lung cancer. Filgrastim use was associated with a hazard ratio of 1.01 (95% CI 1.00–1.03) per administration in breast cancer and 1.02 (95% CI 0.99–1.05) per administration in lung cancer. Pegfilgrastim was associated with a hazard ratio of 1.08 (95% CI 1.01–1.15) per administration in breast cancer and 1.12 (95% CI 1.00–1.25) per administration in lung cancer. Analyses in prostate cancer were limited because of the low number of events. The use of G-CSF in patients diagnosed with breast and lung cancer is associated with an increased risk of MDS-AML. However, the MDS-AML absolute risk difference is very low.

314 Background: FN is a primary driver of chemotherapy modification and reduced RDI. Breast cancer patients often receive regimens with high risk ( > 20%) for FN. PP G-CSF use is recommended to decrease incidence of infection, as manifested by FN. Real-world evidence describing the association of G-CSF with reduced RDI in breast cancer patients is lacking. Methods: We retrospectively analyzed Flatiron Health Electronic Health Record data from 2011 to 2019 of adult female breast cancer patients initiating high-risk for FN chemotherapy regimens. PP G-CSF (pegfilgrastim, filgrastim, or biosimilars) use was assessed in the first and subsequent cycles of chemotherapy overall and by modality (on-body injector [OBI] vs. pre-filled syringe [PFS]). Standard dose was defined by NCCN guidelines. RDI was defined with respect to dose and timing of delivery: (delivered dose intensity/standard dose intensity)*100 and categorized as < 85% vs ≥85%. Characteristics were described by G-CSF use and adjusted relative risks (ARRs) were estimated for the association between G-CSF use and RDI, adjusting for age, serum hemoglobin, ECOG, HER2 status, and HR status. Results: There were 27,812 breast cancer patients included with a median age of 57 years. Most (90%) received PP-G-CSF. Four cycles of TC (docetaxel + cyclophosphamide) was the most common regimen prescribed (36%) and 82% of these patients received PP-G-CSF support in the first cycle, with OBI given more often than PFS (62% vs 38%). Second most common was dd AC-T Q1W (doxorubicin + cyclophosphamide followed by paclitaxel) and 98% of these patients received PP G-CSF (59% OBI vs 41% PFS). 80% of G-CSF users (vs 48% of those with no G-CSF) completed 4 or more cycles of chemotherapy (all regimens had ≥4 planned cycles). G-CSF users had a significant reduction in risk of RDI < 85% in Cycle 1 (ARR: 0.60; 95% confidence interval [CI]: 0.43 – 0.85) and Cycle 2 (ARR: 0.76; 95% CI: 0.59 – 0.97). At the overall chemotherapy course level, the risk of RDI < 85% was not significantly different by G-CSF use (ARR: 0.83; 95% CI: 0.63 - 1.08). There was no significant difference in risk of reduced RDI between OBI and PFS (ARR: 1.13; 95% CI: 0.94 - 1.35). Conclusions: This study revealed that 90% of breast cancer patients receiving high-risk for FN chemotherapy received PP-G-CSF support and completed more cycles than those who did not receive G-CSF. G-CSF users had lower risk of a reduced RDI in Cycles 1 and 2.

INTRODUCTION:Chemotherapy-induced thrombocytopenia (CIT) contributes to treatment dose delay and/or modification, often resulting in poorer survival and disease progression. We explored the incidence and clinical consequences of CIT among metastatic colorectal cancer (mCRC) patients.MATERIALS AND METHODS:Data from two prospective randomized phase 3 trials of mCRC patients receiving either first-line FOLFOX4 (fluorouracil, leucovorin, oxaliplatin) or second-line FOLFIRI (fluorouracil, leucovorin, irinotecan) were analyzed. Thrombocytopenia was defined by platelet count < 100 × 109/L (further categorized by grade) and by recorded adverse events (AEs). Co-occurrence of anemia (hemoglobin < 12 g/dL) and neutropenia (neutrophil count < 2 × 109/L) and clinical consequences of CIT were also evaluated.RESULTS:Among 1078 mCRC patients in the FOLFOX4 study, cumulative incidence of CIT based on platelet count was 37% (grade 3, 2%; grade 4, 1%) during an average 8 months' follow-up. Neutropenia or anemia were absent in 44% of CIT episodes; 62% of CIT AEs led to chemotherapy dose delay, change, and/or discontinuation. Among 1067 mCRC patients in the FOLFIRI study, cumulative incidence of CIT based on platelet count was 4% (grade 3, < 1%; grade 4, 0) during an average 4 months' follow-up. Neutropenia or anemia were absent in 22% of CIT episodes; 32% of CIT AEs led to chemotherapy dose delay, change, and/or discontinuation. With both regimens, transfusions and hospitalizations after CIT AEs were rare (< 3%).CONCLUSION:CIT was common among mCRC patients receiving the FOLFOX4 regimen. The most frequent consequence of CIT was a delay in chemotherapy, highlighting the unmet need in CIT management.

To estimate the risk of thrombocytopenia in various cancers and chemotherapy regimens.

Immune thrombocytopenia (ITP) is the most common bleeding disorder diagnosed in children. Characterized by low platelet counts, it leads to reduced clotting abilities and an increased tendency to bleed. The disorder in children is often self-limiting. However, approximately 25% of children develop persistent or chronic ITP, and bleeding associated with thrombocytopenia can be life-threatening. The current incidence of ITP in the US and the characterization of the illness among children being managed in routine clinical practice are sparsely reported. This retrospective cohort study leveraged a large US-based commercial claims database to estimate the current incidence of pediatric ITP, the uptake of ITP treatments, and the occurrence of clinical outcomes of interest. Overall, the incidence of ITP in patients <18 years was 8.8 (95% confidence interval; 8.5-9.1) per 100,000 person-years from 2011 to 2016. Within two years of ITP onset, >31% of patients received IVIg and/or oral corticosteroids. Other ITP therapies were less common. During this same time period, 50% had at least one bleeding event (ecchymosis, epistaxis, gastrointestinal hemorrhage, etc.), 24% were hospitalized for a bleeding event, and 62% had at least one ITP-related hospitalization. The majority of patients experiencing these events did so within the first month following ITP onset. Our findings confirm the rarity of ITP and relatively low likelihood of chronic disease in young patients, but reveal that for a significant proportion of patients in the newly diagnosed phase, clinical consequences can be serious. Further study of improved treatment methods throughout the disease course is warranted.

To describe temporal trends in treatment among older adult (>= 66 years) patients diagnosed with diffuse large B-cell lymphoma (DLBCL), we analyzed 18,058 DLBCL patients from the Surveillance, Epidemiology, and End Results linked Medicare (SEER-Medicare) database diagnosed between 2001 and 2013. Among 65% of patients receiving treatment after diagnosis, R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisone) was the most common frontline therapy, increasing with more recent treatment year: 51% (2001-2003) vs. 69% (2010-2014). Autologous and allogeneic hematopoietic stem cell transplantation (HSCT) was uncommon in these Medicare patients. As the addition of rituximab increased over time, we also observed an improved survival rate over time. It is possible there is an association, but we cannot make this inference as effectiveness was not measured in this study. Overall survival estimates indicated that survival probabilities steadily improved in more recent years; however, 5-year survival was <40%, indicating the need for improved treatment options for older adult DLBCL patients.

1555 Background: Thrombocytopenia is a common toxicity of chemotherapy, yet there are limited data on its occurrence in routine clinical practice. Methods: Using structured patient-level data from the Flatiron Health EHR-derived database, we assessed risk (3-month cumulative incidence) of chemotherapy-induced thrombocytopenia (CIT) in adult patients (2012-2017) based on platelet counts, overall and by each grade of CIT, cancer type, and chemotherapy regimen (Table); and the co-occurrence of other hematologic abnormalities. Results: Of 15,521 solid tumor patients who initiated chemotherapy, 13% had evidence of CIT within 3 months (platelet count <100x109/L), 4% had grade 3 (25 to <50x109/L) and 2% had grade 4 (<25x109/L) CIT. Of the solid tumors examined, incidence was highest in melanoma patients. In hematologic malignancies (N = 2,537), 3-month risk was even higher with nearly 30%, 16%, and 12% having any grade, grade 3 and 4 CIT, respectively; and the greatest risk being in multiple myeloma patients. Anthracycline-based regimens were associated with the highest risk of CIT (7% grade 3; 4% grade 4), followed by gemcitabine- and platinum-based regimens. Anemia often accompanied first evidence of CIT (49%); isolated thrombocytopenia occurred in 15%. Conclusions: This study provides a current snapshot of CIT risk in a large sample of adult patients undergoing chemotherapy in routine clinical practice, highlighting patients at highest risk for CIT and underscoring the complexity of managing cancer treatment. [Table: see text]

Introduction: Diffuse large B-cell lymphoma (DLBCL) is an aggressive, sometimes fatal hematologic malignancy and is the most common subtype of Non-Hodgkin's Lymphoma. DLBCL has been readily treated with long, durable remissions with the introduction of rituximab to standard chemotherapy in 1997. The most common front line therapy used to treat DLBCL patients is R-CHOP (Rituximab + Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone). Since DLBCL is primarily a disease of the elderly, the Surveillance, Epidemiology, and End Results program linked with Medicare (SEER-Medicare) database was queried for adult patients (66 years and older) to describe the characteristics of elderly DLBCL patients, current treatment patterns and regimen changes over time, receipt of any type of hematopoietic stem cell transplantation (HSCT), and overall survival.