Olaparib in hormone receptor-positive, HER2-negative metastatic breast cancer with a somatic BRCA2 mutation

The oral poly(adenosine diphosphate-ribose) polymerase inhibitor olaparib is approved for the treatment of patients with human epidermal growth factor 2-negative (HER2-) metastatic breast cancer (mBC) and a germline breast cancer susceptibility gene (BRCA) mutation who have been treated with chemotherapy. This case report describes a 63-year-old postmenopausal woman with somatic BRCA2-mutated mBC who responded to olaparib treatment following multiple prior lines of therapy. The patient presented in January 2012 with locally advanced, hormone receptor-positive (HR+), HER2- BC which, despite initial response to neoadjuvant chemotherapy, recurred as bone disease in February 2014, and subsequently skin (June 2016) and liver (October 2016) metastases. A comprehensive 592-gene next-generation sequencing panel (Caris Life Sciences), performed on a skin biopsy, detected a pathogenic frameshift mutation in BRCA2 (H3154fs, c.9460delC), which was not identified in a 28-gene hereditary cancer germline analysis (Myriad Genetics, Inc.), and was therefore considered to be a somatic mutation. In January 2017, cell-free DNA (cfDNA) analysis (Guardant Health, Inc.) confirmed the BRCA2 H3154fs mutation in plasma. After several lines of chemotherapy and endocrine therapy, deriving clinical benefit from eribulin and capecitabine, the disease progressed by October 2017, and olaparib (300 mg orally twice daily) was initiated in January 2018. By April 2018, the liver lesions had shrunk by 80% and a >90% response in multiple skin lesions was noted. Clinical response was maintained for 8 months, followed by progression in the skin in September 2018. Biopsy of recurrent lesions revealed a novel BRCA2 mutation, E3152del (c.9455_9457delAGG), predicted to restore the open reading frame and presumably the mechanism of resistance to olaparib. Further likely resistance mutations were noted in subsequent cfDNA analyses. This case demonstrated a clinical response with olaparib as a later-line therapy for HR+, HER2- mBC with a somatic BRCA2 mutation.

Expert Insights on Triple-Negative Breast Cancer: Preparing for the Next Wave of Treatments

Heather R. Greene, MSN, FNP, AOCNP®, and Lee S. Schwartzberg, MD, FACP, discussed the current and future treatment landscape for triple-negative breast cancer, including recent and emerging data on approved treatments, novel therapeutic options being investigated, and best practices for identifying and monitoring adverse events associated with PARP and immune checkpoint inhibitors at JADPRO Live 2019.

Abstract PS13-42: Locoregional recurrence in patients with early-stage triple-negative breast cancer receiving neoadjuvant systemic therapy: Patient characteristics and clinical outcomes

Background: Recurrence is common among patients with early-stage triple-negative breast cancer (ESTNBC). There is minimal real-world evidence describing the patient characteristics and clinical outcomes following recurrence among patients receiving neoadjuvant chemotherapy for ESTNBC. Methods: This retrospective, observational study aimed to describe the demographic and clinical characteristics and clinical outcomes in ESTNBC patients experiencing locoregional recurrence in the US community oncology setting in the Concerto HealthAI Definitive Oncology Dataset. Eligibility criteria included female sex, age 18+ years, diagnosis of stage II, IIIA or IIIB ESTNBC between 3/2008 and 3/2016, and receipt of definitive surgical resection following neoadjuvant systemic therapy. Descriptive methods were used to evaluate patient characteristics and treatment patterns in this population. Locoregional recurrence was defined as recurrence in the same breast and/or regional nodal recurrence as documented by the provider in the medical record. Results: Of 308 patients who received neoadjuvant treatment for ESTNBC, 27.3% patients (n=84) observed recurrence, within which 25.0% (n=21) were locoregional and 75.0% (n=63) were metastatic. All 21 patients with locoregional recurrence were 65 or younger, with mean age of 50.6 (SD 8.7) at initial diagnosis. They were primarily White (47.6%, n=10) or African American (42.9%, n=9). Over half of patients were stage II at initial diagnosis (61.9%, n=13), while 38.1% (n=8) were stage III. The majority had ductal histology (90.5%, n=19) and had Grade 3 tumors (90.5%, n=19). Of the 21 patients with locoregional recurrence, less than one-tenth (9.5%, n=2) had achieved pathologic complete response (pCR) prior to their recurrence, compared to 41.2% (n=127) of the 308 patients receiving neoadjuvant treatment. In terms of treatment following locoregional recurrence, two-thirds of patients received radiation therapy (66.6%, n=14) with median duration of 47.5 days. Over half of patients (57.1%, n=12) had mastectomy following recurrence, while 14.3% (n=3) had partial mastectomy (breast conserving surgery). Most patients (85.7%, n=18) received systemic chemotherapy after recurrence. Median duration of systemic therapy following locoregional recurrence was 108 days. Nearly one-half (47.6%, n=10) had a subsequent metastatic diagnosis and nearly one-third (28.6%, n=6) had a record of death. Median time from locoregional recurrence to metastatic diagnosis was 36.6 months, but median time from locoregional recurrence to death was not reached. Conclusions: Among patients who received neoadjuvant therapy for ESTNBC in the real-world setting, nearly 7% (n=21) experienced locoregional recurrence. Nearly one-fourth of those patients had a prior pCR which potentially suggests a higher risk of recurrence associated with ESTNBC patients. Chemotherapy was the mainstay of treatment following recurrence. Most patients also received radiation therapy and surgery, but despite those nearly one-half of the patients went on to have a subsequent metastatic diagnosis. This probably reflects the limitations of existing treatment modalities for ESTNBC patients. Future studies with a bigger sample size could confirm our findings. Our study provides some benchmark perspective to such future studies.

Citation Format: Amin Haiderali, Whitney C. Rhodes, Santosh Gautam, Min Huang, Jan Sieluk, Karen E. Skinner, Lee S. Schwartzberg. Locoregional recurrence in patients with early-stage triple-negative breast cancer receiving neoadjuvant systemic therapy: Patient characteristics and clinical outcomes [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS13-42.

Abstract PS9-59: Pooled efficacy analysis from two phase 3 studies in patients receiving eflapegrastim, a novel, long-acting granulocyte-colony stimulating factor, following TC for early-stage breast cancer

Background: Eflapegrastim (Rolontis®, Efla) represents the first novel, long-acting granulocyte-colony stimulating factor (G-CSF) to be introduced in more than 15 years. Efla consists of a recombinant human G-CSF analog conjugated to a human IgG4 Fc fragment via a polyethylene glycol linker. Preclinical, clinical, and pharmacodynamic/pharmacokinetic data have shown increased potency for Efla versus pegfilgrastim (Peg). Both independent, randomized Phase 3 studies comparing Efla and Peg for prophylaxis of chemotherapy-induced neutropenia in patients with early-stage breast cancer (ESBC) met the primary endpoint of non-inferiority in duration of severe neutropenia (SN; ANC<0.5 × 109/L) (p<0.001) for Efla vs Peg in all 4 treatment cycles. Additionally, one of the studies exhibited a statistically significant reduction in the relative risk of SN in Cycle 1 with Efla. Here we provide a pooled analysis across the two pivotal studies comparing Efla vs Peg for SN in various subgroups. Methods: Patients with ESBC, who were candidates for adjuvant or neoadjuvant chemotherapy, were randomized 1:1 in two open-label Phase 3 studies to fixed-dose Efla (3.6 mg G-CSF) or standard Peg (6 mg G-CSF) administered on Day 2 following TC (docetaxel/cyclophosphamide) for a total of 4 cycles. ANCs were collected daily in Cycle 1 and 5 times in Cycles 2-4. SN was evaluated between treatment groups in Cycle 1 using Fisher’s exact test at 5% level of significance and was analyzed using multivariate logistic and Cox proportional hazards regression models. Results: A total of 643 patients who received either Efla (n=314) or Peg (n=329) were included in the analysis. The two treatment groups were well balanced for demographics and baseline characteristics. The mean age was 59 years, 38% were ≥65 years old, and 54% weighed >75kg. The safety profiles, including AEs and discontinuations, for Efla and Peg were comparable, and >99% of all patients received full dose of TC on schedule. The majority (67%) of patients with SN experienced a 1 day duration, occurring between Days 7 and 8 after TC. Mean duration of SN for Efla was statistically lower than for Peg (0.24 vs. 0.36 days; p=0.029). The above statistical significance was maintained for Efla after adjusting for demographic and baseline characteristics, namely age, weight, enrolling geographical region, and treatment setting in a multivariate model. Similarly, the incidence of SN for Efla was statistically lower than Peg in Cycle 1 (17.5% vs 24%; relative risk reduction [RRR]=27%; p=0.043). Univariate analysis of the incidence of SN showed a significant risk reduction in favor of Efla (8.6% vs 14.1%; p=0.034) for patients weighing >75kg (p=0.034). Multivariate analysis of SN showed significant odds ratio of SN for age ≥65 years and baseline ANC >6 × 109/L in favor of Efla (OR=0.42 and 0.39, respectively). The incidence of SN in Cycles 2-4 was comparable between treatment groups. Also, the incidence of febrile neutropenia and neutropenic complications was similar with <5% in each treatment group. No leukocytosis, splenic rupture, or anaphylaxis was reported in any patient receiving Efla or Peg. Conclusion: A pooled analysis of two, randomized Phase 3 studies evaluating Efla vs Peg, administered once-per-cycle for prophylaxis of SN, showed Efla and Peg had similar safety profiles with Efla demonstrating a statistically significant risk reduction in SN overall and in patients weighing >75kg. Eflapegrastim is a novel, long-acting and potent recombinant human G-CSF which may provide an attractive option in supporting patients at risk for SN-related complications.

Citation Format: Lee S Schwartzberg, Gajanan Bhat, Alvaro Restrepo, Osama Hlalah, Inderjit Mehmi, Yong Wha Moon, Seungjae Baek, Shanta Chawla, Francois Lebel, Patrick Wayne Cobb. Pooled efficacy analysis from two phase 3 studies in patients receiving eflapegrastim, a novel, long-acting granulocyte-colony stimulating factor, following TC for early-stage breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS9-59.

Abstract OT-06-01: Open-label, phase 1 study to evaluate duration of severe neutropenia after same-day dosing of eflapegrastim in patients with breast cancer receiving docetaxel and cyclophosphamide (NCT04187898)

Background: Eflapegrastim (Rolontis®, Efla) is a long-acting granulocyte-colony stimulating factor (G-CSF), consisting of a recombinant human G-CSF analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. Efla is not a biosimilar and represents the first myeloid growth factor innovation in more than 15 years. In preclinical studies with chemotherapy-induced neutropenic rats, Efla showed ~3-fold higher exposure in serum and higher exposure in bone marrow at similar doses compared to pegfilgrastim (Peg). The duration of neutropenia (DN) was shown to be significantly shorter with Efla vs Peg when administered on the same day and 24-hours post-chemotherapy. Additionally, the DN after Efla administered on the same day as chemotherapy was similar to the DN 24 hours post-chemotherapy. Moreover, in two Phase 3 studies that randomized a total of 643 patients with early-stage breast cancer (ESBC) to either Efla (3.6 mg G-CSF n=314) or Peg (6 mg G-CSF n=329) given ~ 24 hours after docetaxel and cyclophosphamide (TC) administration, the duration of severe neutropenia (DSN) was statistically noninferior in patients treated with Efla compared to Peg. As a standard of practice, G-CSF products require administration 24 hours after chemotherapy. Since Efla preclinical and clinical results suggest that the increased activity of Efla may provide effective prophylaxis against chemotherapy-induced neutropenia when administered on the same day as chemotherapy, the purpose of this study is to assess the feasibility of Efla same-day (3 different dosing timepoints) in patients receiving TC for treatment of ESBC. Trial Design: This is a randomized, schedule finding, multicenter, Phase 1, open-label study evaluating the same-day administration of 13.2 mg/0.6 mL Efla (3.6 mg G-CSF) following IV infusion of docetaxel (75 mg/m2) and cyclophosphamide (600 mg/m2) in patients with ESBC. Patients will be randomized 1:1:1 to Efla dose schedules of 0.5, 3, and 5 hours after TC. The primary endpoint is DSN (ANC <0.5×109/L) in Cycle 1. The secondary endpoints for Cycle 1 administration include the incidence of SN, time to recovery from SN, incidence of Grade 3 febrile neutropenia, incidence of neutropenic complications, and pharmacokinetics (PK) of Efla. Blood for hematology will be drawn daily for the first 10 days and then on Day 1 of Cycles 2-4. Eligibility Criteria: This study is enrolling histologically confirmed (operable stage I-IIIA) patients with ESBC, who are >18 years of age, are candidates for neoadjuvant or adjuvant TC chemotherapy, have an ECOG of <2, with adequate hematological, renal, and hepatic function. Patients will be excluded if they have a known sensitivity or previous reaction to E. coli derived products, exposure to a G-CSF agent within 3 months, history of bone marrow or hematopoietic stem cell transplant, radiotherapy or surgery within 30 days, are pregnant, or are breast-feeding. Statistical Methods: A sample size of 15 patients per dosing schedule arm was determined to provide adequate precision for the 95% CI of the DSN and secondary endpoints, including PK parameters. The sample size produces a 2-sided 95% CI with a distance from the mean DSN to the limits that is equal to 0.554 using t-distribution when the estimated standard deviation is 1.0 days. A safety evaluation will be performed once the first three patients in each arm have completed Cycle 1. Target Accrual: 45 patients (15 subjects/arm). Enrollment began in April 2020.

Citation Format: Lee S. Schwartzberg, Jawad Francis, Hlalah Osama, Manuel Modiano, Jayaram Bharadwaj, Shanta Chawla, Gajanan Bhat, Francois Lebel, Nishan Tchekmedyian. Open-label, phase 1 study to evaluate duration of severe neutropenia after same-day dosing of eflapegrastim in patients with breast cancer receiving docetaxel and cyclophosphamide (NCT04187898) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-06-01.

Real-world effectiveness outcomes in patients diagnosed with metastatic triple-negative breast cancer

Aim: This study examined treatment patterns and effectiveness outcomes of patients with metastatic triple-negative breast cancer (mTNBC) from US community oncology centers. Materials & methods: Eligible patients were females, aged ≥18 years, diagnosed with mTNBC between 1 January 2010 and 31 January 2016. Kaplan-Meier and Cox regression methods were used. Results: Sample comprised 608 patients with average age of 57.5 years and 505/608 patients (83.1%) received systemic treatment. Overall survival (OS) from first-line treatment found that African-American patients had shorter OS than White (9.3 vs 13.7 months; hazard ratio: 1.35; p = 0.006). Conclusion: More than 15% of women with mTNBC were not treated, indicating a high unmet need. Overall prognosis remains poor, which highlights the opportunity for newer therapies to improve progression-free survival and OS.

Assessing direct costs of treating metastatic triple-negative breast cancer in the USA

Aim: Evaluation of monthly cost during metastatic triple-negative breast cancer (mTNBC) treatment. Patients & methods: Retrospective electronic medical record review of US females aged ≥18 years diagnosed with mTNBC between 1 January 2010 and 31 January 2016. Mean monthly costs per patient were evaluated from start of mTNBC treatment until transfer to hospice, end of record or 3 months prior to death. Results: The mean monthly cost of first line was $21,908 for 505 treated patients; 50.2% of cost was attributable to hospitalization and emergency department visits, and 32.7% to anticancer therapy. Similar patterns were observed for subsequent lines of therapy. Conclusion: The majority of costs were attributable to hospitalization and emergency department services, suggesting a need for effective interventions to reduce utilization of costly services.

Use of antiemetic prophylaxis and oral breakthrough medication for highly emetogenic chemotherapy (HEC) in a large community oncology network

253

Background: Prophylaxis for highly emetogenic chemotherapy (HEC) is well established in clinical guidelines, but real-world treatment patterns are unclear. Today, consistent use of prophylaxis is more easily accomplished due to the incorporation of ordering premeds into the workflow prior to administration of intravenous chemotherapy. However, prescription of oral agents for treatment of breakthrough chemotherapy induced nausea and vomiting (CINV) is less consistent and standardized and has a scant evidence base. In an effort to standardize utilization, we evaluated the use of prophylaxis and oral breakthrough medications in a large national community oncology network. Methods: Data from electronic medical records at five practices comprising over 100 clinic sites was analyzed to examine the frequency of guideline-recommended triplet 5-HT3 receptor antagonist, NK-1 receptor antagonist, and corticosteroid use for prophylaxis prior to the administration of HEC agents. Oral breakthrough medication use and preference was also analyzed. Data was collected and analyzed at the practice level. Results: We identified 2645 patients that received HEC between 1/1/2019 and 5/8/2020. We found consistently high utilization of guideline-concordant triplet prophylaxis regimens for patients receiving HEC, ranging from 90-100% at each of the five practices. In addition, most patients (mean 83%, range 67% - 94%) received a prescription for at least one oral breakthrough medication, but the agent(s) utilized varied widely across practices (Table). Ondansetron was the most commonly prescribed oral breakthrough medication (mean 68%, range 53% - 88%), while olanzapine use for either prophylaxis or breakthrough CINV across practices ranged from 1% - 4%. Conclusions: In this national community oncology network, standard recommended triplet agent prophylaxis for HEC was delivered successfully. However, opportunity exists to increase appropriate use of olanzapine and reduce variation of oral breakthrough antiemetic medications in order to optimize clinical care. [Table: see text]

Real-world patterns of chemotherapy and immunotherapy utilization at end of life in a large community oncology network

22

Background: End-of-life anti-neoplastic treatment does not improve quality of life nor prolong survival of advanced cancer patients. It is also not cost-effective. To-date, there has been little data examining real-world patterns of chemotherapy and immunotherapy treatment at end of life. We investigated use of chemotherapy and/or immunotherapy in the last 14 days of life across a community oncology network of 5 practices, 100 sites of care, and 160 oncology providers. Methods: Using a real-time, network-wide database, we identified patients with solid tumor malignancies who died during an episode of active treatment, defined as having received intravenous (IV) chemotherapy and/or immunotherapy within 90 days of death. We then identified patients in this cohort who received IV chemotherapy and/or IV immunotherapy within 14 days of death (TxEoL). We studied TxEoL patterns by cancer type, treatment type, line of therapy, patient age, patient race, and oncology provider years in practice. Statistical significance was assessed using Pearson’s Chi-squared test. Results: 2,858 qualifying solid tumor cancer patients with dates of death between 1/1/2019 and 5/31/2020 were identified. Observed rates of TxEoL were 16.7% for immunotherapy alone vs. 19.6% for chemotherapy +/- immunotherapy (p = 0.09). We found high variation in TxEoL across 132 oncologists that had 5 or more deceased patients (range: 0% to 50%, mean: 19.2%, median: 19.6%). We found no association of TxEOL with physician years in practice, patient age or race. Rates of TxEoL in the first-line setting were significantly higher than in second-line setting or later (23.3% versus 16.4%, p < 0.01). Patients with head and neck, pancreatic, and hepatobiliary malignancies were the most likely to receive TxEoL, while patients with prostate, brain, and ovarian malignancies were the least likely to receive TxEoL. Conclusions: Our data and method identified wide variation in TxEoL patterns across a large community oncology network, suggesting room for provider-level interventions to improve treatment decisions in patients at high risk of death. Studies within our group, such as examining the impact of palliative care referrals on IV anti-cancer treatment in patients potentially facing end of life, are ongoing.

Feasibility of and associated cost savings from transitioning to therapeutic biosimilar use in a large community oncology network

9

Background: The use of biosimilar drugs in the treatment of cancer offer an opportunity for oncology providers to decrease total cost of care while preserving quality. However, it remains unclear whether providers and patients may resist biosimilar use due to concerns over safety and efficacy. Our national network of 5 practices with over 100 clinics committed to a conversion to therapeutic biosimilars for trastuzumab and bevacizumab after their introduction in July 2019. Methods: Common steps to foster therapeutic biosimilar conversion included frequent communication from medical directors to providers and staff, incorporation of biosimilars into default treatment regimen orders, providing clinical teams lists identifying candidates for conversion, and tracking reasons why biosimilar switch did not occur. Most practices prioritized converting patients initiating new treatments, then later transitioning patients receiving maintenance therapy. This phased approach was taken to ensure that prior authorization and patient consent could be obtained prior to conversion. Rates of biosimilar use were calculated by comparing the number of administrations for which a biosimilar was given to the total number of administrations for which a biosimilar could have been given. Cost savings were calculated by comparing the difference in Medicare allowed rates for each originator and biosimilar drug pair at the time of administration. Results: Biosimilar use increased over time at all practices, from 0% to an average of 67% for trastuzumab and 78% for bevacizumab. The decrease in cost attributed to the use of biosimilars in the study period totaled over $4.4 million. Challenges to biosimilar use included physician preference for the originator drug, difference in preferred agents across payers, and challenges with biosimilar drug storage. Patients rarely had concerns over efficacy and safety. Conclusions: Therapeutic biosimilar adoption in a large oncology network is feasible and can lead to significant cost savings. [Table: see text]

Finding value in social media: A collaborative online communication platform linking providers to education and an online tumor board across a large community of oncology practices

305

Background: Clinical collaboration across fragmented and often small clinic sites can be challenging. As a potential solution, OneOncology, a national community oncology network, launched OneCommunity, a secure, interactive online platform used across our network of six practices and over 130 clinic sites. One feature is a “virtual” tumor board where physicians can post complex cases at any time and obtain input from disease-specific experts from within the network. Members can also post, comment and disseminate information about policy and education updates affecting oncology. Methods: OneCommunity launched on December 15, 2019 and all 442 members of OneOncology were allowed access. We tracked numbers of membership, tumor board cases, policy updates and questions, views and responses per post, and response time for tumor board and policy posts during the study period from launch through June 11, 2020. Results: In the first six months of use, 277 providers signed up and logged into the platform. 71 individual patient cases were presented across 10 specialty tumor boards. The mean time to first response was 35 hours ( < 1 hour, 297 hours), median time was 20 hours, and 73% of postings had a response within 48 hours of original posting. The most robust tumor boards were breast, GI, and lung cancers. There was also a set of general posts that was nonspecific to patients including policy, COVID updates, and educational reviews. The average number of responses for tumor boards was significantly greater than general posts (3.5 vs. 1.8, p < 0.05). The number of views for both types of posts, however, were high (406 vs. 346, p < 0.05). Conclusions: An online communication platform is feasible and allows physicians to receive treatment suggestions for complex cases relatively quickly and across geographies. Tumor board cases received more interaction than policy and education updates. The platform lends itself to rapidly adding other aspects of cancer care such as COVID-19. Future applications include a network wide real-time molecular tumor board.

Prevalence of Phosphatidylinositol-3-Kinase (PI3K) Pathway Alterations and Co-alteration of Other Molecular Markers in Breast Cancer

Background: PI3K/AKT signaling pathway is activated in breast cancer and associated with cell survival. We explored the prevalence of PI3K pathway alterations and co-expression with other markers in breast cancer subtypes. Methods: Samples of non-matched primary and metastatic breast cancer submitted to a CLIA-certified genomics laboratory were molecularly profiled to identify pathogenic or presumed pathogenic mutations in the PIK3CA-AKT1-PTEN pathway using next generation sequencing. Cases with loss of PTEN by IHC were also included. The frequency of co-alterations was examined, including DNA damage response pathways and markers of response to immuno-oncology agents. Results: Of 4,895 tumors profiled, 3,558 (72.7%) had at least one alteration in the PIK3CA-AKT1-PTEN pathway: 1,472 (30.1%) harbored a PIK3CA mutation, 174 (3.6%) an AKT1 mutation, 2,682 (54.8%) had PTEN alterations (PTEN mutation in 7.0% and/or PTEN loss by IHC in 51.4% of cases), 81 (1.7%) harbored a PIK3R1 mutation, and 4 (0.08%) a PIK3R2 mutation. Most of the cohort consisted of metastatic sites (n = 2974, 60.8%), with PIK3CA mutation frequency increased in metastatic (32.1%) compared to primary sites (26.9%), p < 0.001. Other PIK3CA mutations were identified in 388 (7.9%) specimens, classified as "off-label," as they were not included in the FDA-approved companion test for PIK3CA mutations. Notable co-alterations included increased PD-L1 expression and high tumor mutational burden in PIK3CA-AKT1-PTEN mutated cohorts. Novel concurrent mutations were identified including CDH1 mutations. Conclusions: Findings from this cohort support further exploration of the clinical benefit of PI3K inhibitors for "off-label" PIK3CA mutations and combination strategies with potential clinical benefit for patients with breast cancer.

A comparison of eflapegrastim to pegfilgrastim in the management of chemotherapy-induced neutropenia in patients with early-stage breast cancer undergoing cytotoxic chemotherapy (RECOVER): A Phase 3 study

Eflapegrastim (Rolontis^®) is a novel, long‐acting hematopoietic growth factor consisting of a recombinant human granulocyte‐colony stimulating factor (rhG‐CSF) analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. We report results from a second pivotal, randomized, open‐label, Phase 3 study comparing the efficacy and safety of eflapegrastim to pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia. Patients with Stage I to IIIA early‐stage breast cancer (ESBC) were randomized 1:1 to fixed‐dose eflapegrastim 13.2 mg (3.6 mg G‐CSF) or pegfilgrastim (6 mg G‐CSF) administered one day after standard docetaxel/cyclophosphamide (TC) therapy for four cycles. The primary objective was to demonstrate noninferiority (NI) of eflapegrastim compared to pegfilgrastim in mean duration of severe neutropenia (DSN; Grade 4) in Cycle 1. A total of 237 eligible patients were randomized 1:1 to receive either eflapegrastim (n = 118) or pegfilgrastim (n = 119). Cycle 1 severe neutropenia was observed in 20.3% (n = 24) of patients receiving eflapegrastim and 23.5% (n = 28) receiving pegfilgrastim. The DSN of eflapegrastim in Cycle 1 was noninferior to pegfilgrastim with a mean difference of −0.074 days (NI P‐value < .0001). Noninferiority was maintained throughout the four treatment cycles (P < .0001 in all cycles). Other efficacy endpoints results were comparable between treatment arms, and adverse events, irrespective of causality and grade, were comparable between treatment arms. The results demonstrate noninferior efficacy and comparable safety for eflapegrastim, at a lower G‐CSF dose, vs pegfilgrastim. The potential for the increased potency of eflapegrastim to deliver improved clinical benefit warrants further clinical study.

Liquid biopsy mutation panel for non-small cell lung cancer: analytical validation and clinical concordance

Molecular testing for genomic variants is recommended in advanced non-small cell lung cancer (NSCLC). Standard tissue biopsy is sometimes infeasible, procedurally risky, or insufficient in tumor tissue quantity. We present the analytical validation and concordance study of EGFR variants using a new 17-gene liquid biopsy assay (NCT02762877). Of 144 patients enrolled with newly diagnosed or progressive stage IV nonsquamous NSCLC, 140 (97%) had liquid assay results, and 117 (81%) had both EGFR blood and tissue results. Alterations were detected in 58% of liquid samples. Overall tissue-liquid concordance for EGFR alterations was 94.0% (95% CI 88.1%, 97.6%) with positive percent agreement of 76.7% (57.7%, 90.1%) and negative percent agreement of 100% (95.8%, 100%). Concordance for ALK structural variants was 95.7% (90.1%, 98.6%). This assay detected alterations in other therapeutically relevant genes at a rate similar to tissue analysis. These results demonstrate the analytical and clinical validity of this 17-gene assay.

Eflapegrastim, a Long-Acting Granulocyte-Colony Stimulating Factor for the Management of Chemotherapy-Induced Neutropenia: Results of a Phase III Trial

Background

Eflapegrastim, a novel, long‐acting recombinant human granulocyte‐colony stimulating factor (rhG‐CSF), consists of a rhG‐CSF analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. Preclinical and phase I and II pharmacodynamic and pharmacokinetic data showed increased potency for neutrophil counts for eflapegrastim versus pegfilgrastim. This open‐label phase III trial compared the efficacy and safety of eflapegrastim with pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia.

Materials and Methods

Patients with early‐stage breast cancer were randomized 1:1 to fixed‐dose eflapegrastim 13.2 mg (3.6 mg G‐CSF) or standard pegfilgrastim (6 mg G‐CSF) following standard docetaxel plus cyclophosphamide chemotherapy for 4 cycles. The primary objective was to demonstrate the noninferiority of eflapegrastim compared with pegfilgrastim in mean duration of severe neutropenia (DSN; grade 4) in cycle 1.

Results

Eligible patients were randomized 1:1 to study arms (eflapegrastim, n = 196; pegfilgrastim, n = 210). The incidence of cycle 1 severe neutropenia was 16% (n = 31) for eflapegrastim versus 24% (n = 51) for pegfilgrastim, reducing the relative risk by 35% (p = .034). The difference in mean cycle 1 DSN (−0.148 day) met the primary endpoint of noninferiority (p < .0001) and also showed statistical superiority for eflapegrastim (p = .013). Noninferiority was maintained for the duration of treatment (all cycles, p < .0001), and secondary efficacy endpoints and safety results were also comparable for study arms.

Conclusion

These results demonstrate noninferiority and comparable safety for eflapegrastim at a lower G‐CSF dose versus pegfilgrastim. The potential for increased potency of eflapegrastim to deliver improved clinical benefit warrants further clinical study in patients at higher risk for CIN.

Implications for Practice

Chemotherapy‐induced neutropenia (CIN) remains a significant clinical dilemma for oncology patients who are striving to complete their prescribed chemotherapy regimen. In a randomized, phase III trial comparing eflapegrastim to pegfilgrastim in the prevention of CIN, the efficacy of eflapegrastim was noninferior to pegfilgrastim and had comparable safety. Nevertheless, the risk of CIN remains a great concern for patients undergoing chemotherapy, as the condition frequently results in chemotherapy delays, dose reductions, and treatment discontinuations.

Myelosuppression, particularly neutropenia, has presented a major challenge in cancer treatment since the introduction of cytotoxic chemotherapy. This article reports the results of a phase III trial that compared the efficacy and safety of eflapegrastim with pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia.

Real-world evaluation of effectiveness and tolerance of chemotherapy for early-stage breast cancer in older women

PURPOSE

Older patients with early-stage breast cancer (ESBC) tend to receive less aggressive treatment, have higher mortality rates, and are underrepresented in clinical trials. Outcomes, tolerance and toxicity of chemotherapy are underreported. Thus, we assessed the outcomes of chemotherapy in the real-world in a community oncology setting.

METHODS

We retrospectively chart reviewed consecutive older patients (≥ 70 years) with ESBC diagnosed between January 1, 2010, and December 31, 2016, who received chemotherapy at our institution. Study outcomes were survival estimates. Logistic regression determined associations with measures of intolerance.

RESULTS

Of 1296 patients, 229 received chemotherapy. Overall, 24% had early chemotherapy cessation; 18% had dose reductions; and 27% had dose delays. Severe, life threatening and lethal toxicities occurred in 38%, 1.3%, and 2.2%, respectively; constitutional toxicity (37%) was the most common. The 1- and 3-year overall survivals were 94% and 79%; 1- and 3-year breast-specific survivals were 96% and 89%, while 1- and 3-year disease-free survivals were 95% and 82%, respectively. Anthracyclines were the most poorly tolerated regimen having associations with hospital visits (OR 10.97, 95% CI 2.10-57.23) and severe toxicities (OR 5.28, 95% CI 1.27-21.89). Anti-HER2 therapies (OR 3.03, 95% CI 1.18-7.78) and poorer performance status (PS) (OR 7.48, 95% CI 1.75-31.98) were associated with severe toxicities. Older age (> 80 years) was associated with early cessation of therapy (OR 3.64, 95% CI 1.34-9.83).

CONCLUSIONS

Chemotherapy can be effectively delivered to older patients with ESBC and is reasonably well tolerated. The high rate of anthracycline intolerability, poorer PS, and advanced age should be considered when tailoring treatment regimens.

Racial and socioeconomic disparities in overall survival in colorectal cancer (CRC) at West Cancer Center & Research Institute (WCCRI), Memphis, TN

e16122

Background: WCCRI, a comprehensive regional community oncology center in Memphis, Tennessee and the Mid-South region, serves a racially, geographically and socioeconomically diverse patient cohort. We sought to evaluate disparity of outcomes in survival by race and socioeconomic status, in addition to patient and tumor characteristics. Methods: All consecutive patients referred to and treated at WCCRI with colorectal adenocarcinoma from 2007-2013 were included. Individual chart review was performed to verify diagnosis, stage, and date and cause of death. Kaplan-Meier Overall Survival curves were generated for the entire cohort and by race, sex, tumor location and income derived from zip code. WCCRI survival data were compared to SEER data. Results: From 2007-2013, 1,176 patients were included in the analysis: 405 blacks, 757 whites, 14 others. Median age at diagnosis: Blacks 58 yrs, whites 61 yrs. Stage distribution at diagnosis: stage 1: 100, stage 2: 275, stage 3: 425, stage 4: 376. All stages combined, blacks trended towards shorter OS vs whites (5-year OS: 52.8% vs 58.3%; median survival 71.0 mos vs 98.6 mos; p= 0.095). Blacks presented at later stages (71.4% at stage 3 or 4 vs 66.3% for whites) but no statistically significant OS differences were seen when compared by stage. Patients at or below the median income of $39,590 for WCC had worse 5-year OS (51.6% vs. 61.1%; p= 0.006), as did patients without private insurance (5-year OS: uninsured: 48.0%, Medicare/Medicaid: 50.0%, private: 62.0%; p< 0.001). Adjusted for stage, 5-year OS was statistically significant for stage 4 (private: 18.0%, Medicare/Medicaid: 9.4%, uninsured: 8.3%; p= 0.020). A higher proportion of blacks were below the median income (69% vs 39%) but no statistically significant OS differences were seen when adjusted by race. Overall, cancer survival outcomes were similar to SEER results. Conclusions: At WCCRI, black patients with CRC presented at a later stage than whites, however, adjusted for stage, no significant racial difference in OS was found. Income and insurance status influenced survival outcomes. Overall, our results reveal racial and socioeconomic disparities in colorectal cancer in a diverse US population and further detailed multivariate data analyses are underway.

Real-world incidence, duration, and severity of treatment-emergent (TE) neutropenia among patients (pts) with metastatic breast cancer (MBC) treated with ribociclib (RIB) or palbociclib (PAL)

e13048

Background: Neutropenia is the most common adverse event following administration of CDK4/6 inhibitors RIB and PAL for hormone receptor–positive (HR+) MBC. There are limited comparative real-world data on TE neutropenia in pts receiving these agents. Here we report incidence, duration, and severity data on TE neutropenia in such pts from an electronic health record dataset and administrative claims. Methods: This retrospective study comprised 2 mutually exclusive cohorts of pts with MBC receiving RIB or PAL. Pts were matched 1:1 based on age and year of treatment start. Prior baseline activity of ≥6 mo was required. The MarketScan claims databases was used to evaluate incidence rates of TE neutropenia from Jan 1, 2015, to Dec 31, 2018, in pts receiving RIB or PAL. Rate ratio was calculated using a Poisson model. Data on neutropenia severity and duration were obtained from Optum de-identified Electronic Health Record dataset. Neutropenia severity was defined by neutrophil counts from lab tests (grade 1/2, 1000- < 1500/μL; grade 3, 500- < 1000/μL; grade 4 < 500/μL) within the first 180 days of treatment. Neutropenia duration was estimated using Kaplan-Meier analysis and defined as the time between first abnormal neutrophil result and a lab result demonstrating neutropenia resolution. Results: After 1:1 matching, 152 pts from the MarketScan database were included in both the PAL and RIB cohorts; 168 matched pts were included from the Optum dataset. Neutropenia was reported in 38 pts (25%) in the PAL group and 25 pts (17%) in the RIB group. The rate of neutropenia per person–treatment year was 0.5 (95% CI, 0.4-0.7) in PAL pts vs 0.4 (95% CI, 0.3-0.6) in RIB pts. The rate ratio of neutropenia between treatments (PAL vs RIB) was 1.4 (95% CI, 0.8-2.3), which was not statistically significant, likely due to small sample size. Rates of neutropenia by severity with PAL vs RIB were 32% vs 32% for grade 1/2, 35% vs 26% for grade 3, and 4% vs 4% for grade 4, respectively. The rate ratio for grade 3 or grade 4 neutropenia (PAL vs RIB) was 1.3 (95% CI, 0.9-1.8). Median neutropenia duration was 29 vs 20 days ( P< .01) with PAL vs RIB. Conclusions: Treatment of HR+ MBC with RIB and PAL requires optimal management of TE neutropenia. Real-world data showed that pts with MBC receiving PAL had a numerically higher rate of neutropenia than pts receiving RIB. Rates of grade 3 neutropenia were higher with PAL vs RIB, and duration of neutropenia was longer with PAL vs RIB. Economic burden analyses of neutropenia will be presented.

Work loss and activity impairment due to duration of nausea and vomiting in patients with breast cancer receiving CINV prophylaxis

e24133

Background: The impact of chemotherapy-induced nausea and vomiting (CINV) on work loss and activity impairment is important to patients yet not well described in literature. We sought to evaluate CINV-related work loss and activity impairment and their associations with CINV duration. Methods: In a prospective CINV prophylaxis trial of oral or intravenous netupitant/palonestron (NEPA) + dexamethasone (DEX) (12mg day 1 only) for patients with breast cancer receiving anthracycline + cyclophosphamide (AC), we defined CINV as vomiting or use of rescue medication during days 1-5 after AC. Pre-specified endpoints included CINV duration (0-5 days), patient reported CINV-associated work loss (Work Productivity and Activity Impairment survey), and CINV-related impaired activity [0 (none) - (worst) Likert scale] for chemotherapy cycles 1 and 2. CINV-related work loss and activity impairment could involve nausea with or without vomiting or rescue medication use. We categorized CINV duration as 1-2 days (d) or ≥3 d, and compared results using the chi-squared test. We report here on the first 2 cycles. Results: Survey data was captured for 792 cycles in 402 female patients including 132 (32.8%) employed patients. Mean age was 55.4. CINV was observed in 173 (21.8%) of total cycles. CINV-related work loss was reported in 26 (3.3% of all cycles, 15.0% of cycles with CINV, 38.2% of employed patient cycles with CINV) while 142 had related activity impairment. When we categorized cycles by CINV duration, CINV-related work loss was seen in 25.9% of 81 cycles with ≥3 d CINV duration vs. 5.4% for 92 cycles of 1-2 d of CINV (p < 0.001); mean scores of CINV-related impaired activity were 5.0 for ≥3 d CINV vs 3.0 for 1-2 d CINV (p < 0.001). Conclusions: Despite guideline recommended prophylaxis, CINV occurred in > 20% of AC cycles. In cycles with CINV, CINV-related work loss occurred in 38.2% for employed patients while activity impairment occurred in 82.1% for all patient cycles. The majority of CINV lasted 1-2 d. Notably, ≥3 d of CINV was associated with considerably higher levels of work loss and activity impairment suggesting that duration may be a meaningful measure of CINV impact. Clinical trial information: NCT03403712 . [Table: see text]

Using an ePRO tool to help meet quality metric reporting standards: Screening for tobacco usage and falls risk

e19191

Background: ASCO has implemented the Quality Oncology Practice Initiative (QOPI), a certification program established to evaluate oncology practice performance. Also, a growing number of accreditation (JCAHO) and merit-based organizations (MIPS) maintain falls risk assessment standards. Practices often lack the necessary resources to comply with required metric reporting standards. The study purpose was to document the effectiveness of using an electronic Patient Reported Outcome (ePRO) system to facilitate compliance with a core QOPI standard, documentation of smoking status by second office visit, and with JCAHO and MIPS falls risk assessment. Methods: This study used a retrospective, observational design with ePRO collected via the Patient Care Monitor (PCM), a web-based ePRO system linked to electronic medical record data. All study data were collected as part of routine clinical care at a community oncology practice during an 11-month interval (1/2019–11/2019). Patients at an initial clinic visit completed a tobacco usage survey and a brief falls risk survey on the PCM platform via a handheld e-tablet. Results: Overall, 6,613 unique patients completed the PCM survey (mean age 59; 33% male/67% female; 55.4% White, 38% Black). Cancer type was known for a subset of patients (22% breast, 9% hematologic, 4% lung, 5% colorectal, 3% prostate, 11% other types). Across the collected PRO measures, there was an over 98% completion rate with only 1-2% missing data. A relatively significant proportion (51%) indicated they had never used tobacco products and 15% indicated that they were current users. Among patients who ever used tobacco products, 34% indicated they smoked cigarettes, 4% smoked cigars, and 3% used electronic cigarettes. Over a fifth of patients (22%) indicated they had at least one fall over six months; 10% indicated having experienced one fall; 6% indicated two falls; 6% indicated 3 falls or more. 17% indicated they use an ambulatory aid and 12% reported a recent fall within the past 3 months. Conclusions: This study demonstrates that using an ePRO system is an effective way to screen for tobacco usage and falls risk and can be used to: 1) monitor health-related behaviors to enhance physician-patient communication; 2) provide an audit trail for QOPI, JCAHO, MIPS and other quality metric reporting. Automated collection of PRO data allows the healthcare team to focus their clinical time on patients showing increased risk. Overall, an ePRO system contributes to creating a culture of excellence at community oncology practices.

A multi-stakeholder platform to prospectively link longitudinal real-world clinico-genomic, imaging, and outcomes data for patients with metastatic lung cancer

TPS2087

Background: Making personalized diagnostics and treatments a reality for every cancer patient necessitates comprehensively capturing the patient journey. Real-world data has shown promise for the future of clinical research and advancing precision medicine. However, certain limitations exist such as data quality management as well as bias and confounding factors associated with retrospective analyses. We present a multi-stakeholder platform to prospectively collect and link real-world clinico-genomic, imaging, and outcomes data to longitudinal blood genomic profiling for lung cancer. Methods: This study is enrolling approximately 1000 patients with metastatic non-small cell lung cancer or extensive-stage small cell lung cancer who will initiate standard-of-care systemic anti-neoplastic treatment, regardless of line of therapy, at 20 community oncology and academic practices within the Flatiron Health network. Relevant clinical data points from both structured and unstructured fields will be collected through the electronic health records via technology-enabled abstraction, eliminating the need for case report forms. Digital pathology and clinical images at standard-of-care visits will be collected. Blood samples for circulating tumor DNA (ctDNA) profiling using FoundationOne Liquid will be collected at three timepoints: enrollment, first tumor assessment, and end of treatment. Tumor tissue samples may be submitted at baseline for genomic profiling using FoundationOne CDx. Overall survival follow-up will occur until death, withdrawal of consent, loss to follow-up, or end of study. The objectives are to evaluate 1) the feasibility of building a scalable, prospective platform and 2) the associations between ctDNA and real-world clinical outcomes, including overall survival. Enrollment is ongoing. Clinical trial information: NCT04180176.

Use of real-world data to understand barriers to interventional clinical trial enrollment in community oncology clinics (COC)

2061

Background: Increasing enrollment in clinical trials remains a national priority, yet there are limited data from COCs on the degree to which common trial exclusion criteria (EC) and socioeconomic factors play a role in low enrollment rates. Methods: We analyzed data from the nationwide Flatiron Health electronic health record (EHR) derived de-identified database. COC were eligible if they had given a clinical trial study drug to ≥2 patients (pts)/year. We included pts with one of eight advanced or metastatic solid tumors who received ≥1 line of systemic anticancer therapy between 1/1/2014 and 11/30/2019. We defined EC as either: creatinine > 1.5 mg/dl or Ccl < 45 ml/min, Hb < 9 g/dL, ANC < 1500/ul, plts < 100,000/ul, bilirubin > 1.5 upper limit of normal (uln) or AST/ALT > 2.5 uln within 30 days or ECOG performance status (PS) ≥ 2 within 60 days prior to start of therapy. We calculated the percentage of pts with ≥1 EC relative to the group of candidate pts, stratified by therapy line (1L, 2L, 3L+). We used multivariate logistic regression models to evaluate the effect of EC and socioeconomic factors (age, race, Medicaid) on the likelihood of receiving a clinical study drug for each line of therapy. Results: In this sample of 35 COCs, 26,988 pts received ≥1 systemic therapy. Pts with ≥ 1 EC: 28.4% in 1L, 34.2% in 2L, 37.4% in 3L. Percentages of pts with an ECOG PS ≥ 2 were: 15.6% (1L), 18.2% (2L), 19.8% (3L). Pts receiving a clinical study drug: 1.7% of 26,988 in 1L, 2.0% of 12,738 in 2L, 2.9% of 5,333 in 3L+, and 3.1% in any line. Excluding pts with ≥1 EC from the denominator modestly improved overall accrual: 2.0% of 19,729 in 1L, 2.3% of 8,588 in 2L, 3.7% of 3,470 in 3L+. In multivariate logistic regression, ECOG PS ≥ 2 was strongly associated with not receiving a study drug [odds ratio (95% CI); 1L: 0.25 (0.16-0.4); 2L: 0.28 (0.17-0.49); 3L: 0.21 (0.1-0.44)]. The likelihood of receiving a clinical study drug (any line) was lower for pts who are Black [0.63 (0.48-0.82)], Latino [0.49 (0.32-0.75)], and pts older than 70 years [0.63 (0.54-0.72)]. Medicaid pts were not significantly less likely to receive study drug [0.83 (0.64-1.07)]. Conclusions: In COC, common trial EC reduce pt availability for trials by > 25%. Poor PS is highly prevalent and influential. These EC and complex trial requirements challenge COC’s ability to recruit representative pt populations. Future efforts to increase enrollment in trials must consider common EC along with well known barriers to enrollment of unrepresented groups.

CONTESSA TRIO: A multinational, multicenter, phase (P) II study of tesetaxel (T) plus three different PD-(L)1 inhibitors in patients (Pts) with metastatic triple-negative breast cancer (TNBC) and tesetaxel monotherapy in elderly pts with HER2-metastatic breast cancer (MBC)

TPS1111

Background: Chemotherapy treatments with robust efficacy that preserve quality of life are needed. T is a novel, oral taxane that has potential advantages over currently available taxanes, including: oral administration with a low pill burden and once every 3 week (Q3W) dosing; no observed hypersensitivity reactions; preclinical evidence of central nervous system (CNS) penetration; and improved activity against chemotherapy-resistant tumors. More than 600 pts have been treated with T in clinical studies. T had robust monotherapy activity in a P2 study in 38 pts with HER2-, HR+ MBC, with a confirmed objective response rate (ORR) per RECIST 1.1 of 45%. Methods: CONTESSA TRIO is a 2-cohort, multinational, multicenter, P2 study. In Cohort 1, 90 pts (potential expansion to up to 150 pts) with metastatic TNBC who have not received prior chemotherapy for advanced disease will be randomized 1:1:1 to receive T at 27 mg/m2 Q3W plus either: (1) nivolumab at 360 mg Q3W; (2) pembrolizumab at 200 mg Q3W; or (3) atezolizumab at 1,200 mg Q3W. Nivolumab and pembrolizumab (PD-1 inhibitors) and atezolizumab (a PD-L1 inhibitor) are approved for the treatment of multiple types of cancer; atezolizumab, in combination with nab-paclitaxel, was recently approved in the US for the treatment of metastatic TNBC. The dual primary endpoints for Cohort 1 are ORR and progression-free survival (PFS). A sample size of 30 pts in each PD-(L)1 inhibitor treatment group has approximately 70% power to detect an ORR difference of ≥ 35% between the treatment group with the highest ORR and the treatment group with the lowest ORR. Secondary endpoints include duration of response (DoR) and overall survival (OS). Efficacy results for each of the 3 PD-(L)1 inhibitor combinations will be assessed for correlation with the results of each of the 3 approved PD-L1 diagnostic assays. CONTESSA TRIO is the first randomized clinical study to compare 3 approved PD-(L)1 inhibitors. In Cohort 2, 40 elderly pts (potential expansion to up to 60 pts) with HER2- MBC who have not received prior chemotherapy for advanced disease will receive T monotherapy at 27 mg/m2 Q3W. The primary endpoint for Cohort 2 is ORR. A sample size of 40 will allow the ORR to be estimated with a maximum standard error of < 8%. Secondary endpoints include PFS, DoR and OS. Pts with CNS metastases are eligible for both cohorts. The study was initiated in March 2019. Clinical trial information: NCT03952325 .

Treatment Outcomes in Patients with Metastatic Neuroendocrine Tumors: a Retrospective Analysis of a Community Oncology Database

Purpose

Metastatic neuroendocrine tumors (mNETs) are rare, heterogeneous tumors that present diagnostic and treatment challenges, with limited data on the management of mNETs in clinical practice. The present study was designed to identify current diagnostic and treatment patterns in mNET patients treated in the US community oncology setting.

Methods

Patient-level data was collected from medical records of adults with mNETs from the Vector Oncology Data Warehouse, a comprehensive US community oncology network database.

Results

Of the 263 patients included (median follow-up, 22 months; range, 0.1–193.9), 30.4% (80/263) had intestinal tumors, 11.0% (29/263) had pancreatic, and 58.6% (154/263) had tumors of other or unknown location. Progression-free survival (PFS) from the start of first-line therapy differed significantly by tumor grade (log rank P = 0.0016) and location (P = 0.0044), as did overall survival (OS) (grade, P < 0.0001; location, P = 0.0068). Median PFS and OS for patients with undocumented tumor grade were shorter than for patients with G1/G2 tumors and longer than patients with G3 tumors. Median PFS and OS for patients with other or unknown tumors were shorter than for patients with intestinal tumors.

Conclusions

While potentially confounded by the high number of patients with other or unknown tumor locations, this retrospective study of patients in a US community oncology setting identified the importance of awareness of tumor grade and tumor location at diagnosis, as these were direct correlates of PFS and OS.

Targeting PIK3CA Alterations in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor-2-Negative Advanced Breast Cancer: New Therapeutic Approaches and Practical Considerations

The phosphatidylinositol-3-kinase (PI3K) pathway is frequently dysregulated in human breast cancer. Approximately 30% of all patients with breast cancer will carry mutations of the PIK3CA gene, which encodes the PI3K catalytic subunit isoform p110α. Mutations in PIK3CA have been associated with resistance to endocrine therapy, HER2-directed therapy, and cytotoxic therapy. Early trials of pan-PI3K inhibitors showed little treatment benefit as monotherapy owing to disease resistance arising through enhanced estrogen receptor pathway signaling. Combining PI3K inhibition with endocrine therapy can help overcome resistance. Clinical trials of pan-PI3K inhibitors combined with endocrine therapy demonstrated modest clinical benefits but challenging toxicity profiles, facilitating the development of more selective PI3K-targeting agents. More recent trials of isoform-specific PI3K inhibitors in patients with PIK3CA mutations have shown promising clinical efficacy with a predictable, manageable safety profile. In the present review, we discuss the clinical relevance of mutations of PIK3CA and their potential use as a biomarker to guide treatment choices in patients with HR⁺ HER2^- advanced breast cancer.