Mark S Walker

Mark S Walker
Vector Oncology

PhD

About

152
Publications
9,422
Reads
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2,211
Citations
Citations since 2017
44 Research Items
988 Citations
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2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
Additional affiliations
January 2007 - present
Vector Oncology
Position
  • VP Scientific Affairs
Description
  • Design, conduct and supervise HEOR studies with real world oncology EMR data.
January 1999 - December 2006
Washington University in St. Louis
Position
  • Professor (Assistant)

Publications

Publications (152)
Article
Background: Symptom burden differences may contribute to racial disparities in breast cancer survival. We compared symptom changes from before to during chemotherapy among women with breast cancer. Methods: This observational study followed a cohort of Black and White women diagnosed with Stage I-III, hormone-receptor positive breast cancer from...
Article
Importance: Adjuvant endocrine therapy (AET) reduces breast cancer recurrence, but symptom burden is a key barrier to adherence. Black women have lower AET adherence and worse health outcomes than White women. Objective: To investigate the association between symptom burden and AET adherence differences by race. Design, setting, and participant...
Article
6528 Background: Symptom burden may contribute to racial differences in cancer treatment adherence and survival. Evidence on changes in symptom burden during chemotherapy and whether these differ by race is scarce. We used patient reported outcomes data collected before and after breast cancer chemotherapy initiation to compare symptom burden by ra...
Article
e21172 Background: Analysis of Real World Data (RWD) from Electronic Health Records (EHR) for applications such as Health Economics and Outcomes Research (HEOR) or regulatory submissions requires identification of the lines of therapy (LoT) patients have received. LoTs are typically not captured in EHR and must be manually abstracted. As the use of...
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Background: Limited studies have evaluated palbociclib-based therapy use in patients with advanced/metastatic breast cancer in the real world. This retrospective study used medical records from US community oncology practices to address the gap. Materials & methods: Eligible patients receiving palbociclib-based therapy per label indication from 3 F...
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Background: To compare quality of life of patients treated with cetuximab with or without radiation therapy (±RT) vs. cisplatin±RT for locoregionally advanced squamous cell carcinoma of the head and neck (SCCHN) in the real-world setting. Methods: In this retrospective observational study, electronic medical records and Patient Care Monitor (PCM...
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e19135 Background: Real-world data sources have historically provided limited information about the occurrence of disease progression. As a result, progression-free survival (PFS), a standard effectiveness outcome measure in oncology, has been estimated using proxies such as time-to-discontinuation (TTD) or time-to-next-treatment (TTNT). Curation o...
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The aim of this retrospective study was to assess the efficacy of topical hormonal therapy (THT) to relieve vaginal symptoms resulting from antihormonal therapy in women with hormone receptor–positive breast cancer. A total of 74 breast cancer patients who received THT for vaginal complaints were retrospectively identified and statistically matched...
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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. Meth...
Article
Fulvestrant monotherapy is approved for postmenopausal women with hormone receptor‐positive, metastatic breast cancer (MBC) who progressed following antiendocrine therapy, or those with hormone receptor‐positive, human epidermal receptor 2‐negative advanced breast cancer (BC) not previously treated with endocrine therapy (ET). However, real‐world d...
Article
2566 Background: ICI’s have demonstrated significant clinical benefit since the first FDA approval in 2011 of ipilimumab for metastatic melanoma. Five additional ICI therapies have since been approved across several indications. The objectives of this study were to describe the clinical and demographic features of patients receiving ICI treatment a...
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110 Background: Anecdotal and early evidence suggest ICIs are being used in patients with advanced malignancies and history of AD, despite such patients being typically excluded from traditional clinical trials. We compared the outcomes of patients with or without AD, all of whom had ICI treatment for aNSCLC. Methods: We conducted a retrospective,...
Article
6583 Background: Although pts with AD are routinely excluded from ICI clinical trials, evidence suggests they may be receiving ICI therapy once approved. We sought to understand the prevalence of AD among all pts receiving ICIs in real world clinical care, as well as in advanced non-small cell lung cancer (aNSCLC) alone, and to describe the charact...
Article
9110 Background: Immune Checkpoint Inhibitors (ICIs) were first approved for the treatment of aNSCLC in 2014, and since this time have seen rapid adoption in the marketplace. We sought to describe the characteristics of patients with aNSCLC receiving ICIs in the real-world, as well as to examine treatment patterns and outcomes in the time since ini...
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Aim: Little is known about recent treatment patterns among patients with unresected stage III NSCLC in the real world. This retrospective study used medical records from USA community oncology practices to address this knowledge gap. Materials & methods: Eligible patients were stage III NSCLC adults diagnosed between 1 January 2011 and 1 March 2016...
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Purpose: Bevacizumab is a standard first-line (L1) treatment for metastatic colorectal cancer (mCRC) patients regardless of RAS status. This retrospective study examined treatment patterns and outcomes in a community oncology sample of KRAS mutant mCRC patients treated with chemotherapy (C) or C plus bevacizumab (CB) in L1. Methods: This study u...
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Purpose: Patients with Kirsten rat sarcoma viral oncogene wild-type (KRAS WT) metastatic colorectal cancer (mCRC) treated in first line with bevacizumab (B) or cetuximab (C) plus standard chemo backbones had comparable outcomes in phase III Cancer and Leukemia Group B (CALGB) 80405. We examined comparative effectiveness of B and C regimens in real...
Article
Background: The treatment landscape for women with HR+/HER2- advanced and metastatic breast cancer (A/MBC) is changing as new agents are being combined with more established treatments to achieve greater efficacy in combating resistant and unresponsive disease. The present study is designed to describe patient characteristics, treatment patterns, a...
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Purpose This retrospective study of community oncology patients with breast cancer gene (BRCA)-mutated metastatic breast cancer (MBC) examined treatment outcomes and health resource utilization (HRU) and costs for a sample of patients with human epidermal growth factor receptor 2 (HER2)-negative disease who were either hormone receptor positive (HR...
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This study examined real-world clinical outcomes such as progression-free survival (PFS), time to metastasis (TTM), overall survival (OS), and health-related quality of life (HRQOL) in patients with unresected stage III non-small cell lung cancer (NSCLC) treated in the community setting. A retrospective review of medical records extracted from 10 U...
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189 Background: Despite curative treatment intent, most patients (pts) with unresected Stage III NSCLC progress to metastatic disease. Prior research has shown significant benefits on clinical outcomes when HRQoL is assessed in clinical care, but understanding is limited in Stage III NSCLC. Methods: A retrospective review of community oncology medi...
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Introduction: Current real-world data regarding treatment patterns in advanced bladder cancer in the community setting are limited. This study describes patient characteristics, treatment patterns, and effectiveness outcomes for stage IV bladder cancer in the community setting. Methods: Medical records data of adults diagnosed with stage IV blad...
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Purpose: The purpose of this study was to provide an understanding of the effectiveness of existing therapies in patients with advanced head and neck cancer (HNC), particularly in clinical practice. Methods: Data from the electronic medical records of adult patients diagnosed with locally advanced or metastatic (Stage III-IVc) HNC between Januar...
Article
Aim: Time to treatment and pretreatment costs may be affected by unknown primary tumor site. Methods: This retrospective study used electronic medical record data from patients in ten US community oncology practices. Eligible patients were ≥18 years, diagnosed with cancer of unknown primary (CUP) or known metastatic solid tumor, and presented be...
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Purpose: The goal of this study was to describe patient characteristics, health resource utilization (HRU), and costs associated with treating recurrent or refractory head and neck cancer (HNC) among patients with disease progression in the community oncology setting. Methods: This retrospective observational study was conducted by using data fr...
Article
Background: BRCA-mutated breast cancer remains a heterogeneous disease, with variations in histology, response to treatment, and survival outcomes. These cancers are more likely to be negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) or triple negative (TN). However, some are hormone receptor...
Article
Aims: To assess healthcare costs during treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and following disease progression in patients with advanced non-small cell lung cancer (NSCLC). Methods: A retrospective analysis of medical records of US community oncology practices was conducted. Eligible patients had...
Article
Introduction: Health-related quality of life (HRQOL) in advanced non-small-cell lung cancer (NSCLC) might be affected by the presence of brain metastasis (BM). We report findings from a prospective observational study that examined HRQOL in patients newly diagnosed with advanced NSCLC, with or without baseline BM, through 1 year of follow-up. Pat...
Article
Background: This phase 2, single-arm, multicenter study was designed to determine the treatment activity and safety of single-agent pazopanib in patients with unresectable or metastatic liposarcoma. Methods: Eligible patients had high-grade or intermediate-grade liposarcoma with measurable tumors that were unresectable or metastatic, documented...
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Background Treatment options for advanced nonsquamous non-small cell lung cancer (NSCLC) in the first line include platinum-based doublet therapy with or without bevacizumab. This study examined efficacy outcomes and patient reported outcomes (PROs) in a community oncology patient sample. Methods Advanced nonsquamous NSCLC patients from 34 U.S. co...
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e16032 Background: Current real-world data on patients with metastatic bladder cancer in the community setting are limited. This study describes patient characteristics, health resource utilization (HRU), and costs for this population. Methods: Medical records data from adults diagnosed with stage IV bladder cancer (T4b, node-positive, or distant m...
Article
e17512 Background:Tobacco and heavy alcohol use are important risk factors for head and neck (H&N) cancer. H&N cancer may affect activities of daily life (eg, eating, drinking, swallowing), and can be debilitating to health-related quality of life (HRQOL). This study reports HRQOL findings for patients (pts) with advanced H&N cancer eligible for sy...
Article
e12537 Background: Fulvestrant is a selective estrogen receptor degrader approved as monotherapy for postmenopausal women with estrogen-receptor-positive metastatic breast cancer (MBC) who progress following anti-estrogen therapy. The recent Phase 3 FALCON study for hormone therapy (HT) naïve women showed increased median progression-free survival...
Article
e20590 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are recommended for patients with EGFR mutation-positive advanced non-small cell lung cancer (NSCLC). Limited data are available regarding patient-reported outcomes (PROs) in patients who experience progression on 1st-/2nd-generation TKI treatment, which wa...
Article
e20589 Background: Epidermal growth factor receptor (EGFR)tyrosine kinase inhibitors (TKIs) are recommended for patients (pts) with EGFR mutation ( EGFRm) positive non-small cell lung cancer (NSCLC). Limited data are available for real-world outcomes in pts who experience progression on 1st-/2nd-generation EGFR TKIs, which was the focus of this stu...
Article
396Background: Current real-world data on treatment patterns in metastatic bladder cancer in the community setting are limited. This study describes patient characteristics, treatment patterns, and efficacy outcomes for these patients in the community setting. Methods: Medical records data from adults diagnosed with stage IV or metastatic bladder c...
Article
INTRODUCTION Despite recent advances in CINV prophylaxis, many questions remain unanswered including optimal treatment for hematologic malignancy (HM) patients receiving multi-day chemotherapy regimens. As preparation for stem cell transplant (SCT) and for high grade HM, highly emetogenic chemotherapy (HEC) containing regimens are often utilized. I...
Article
77 Background: THR is sometimes used for treatment of VC in BC patients previously treated with HT. The safety of this practice remains a question but the effectiveness of this strategy has not been reported. Methods: We conducted a retrospective analysis of patient reported symptoms at the West Cancer Center (WCC) between 2002 and 2014. Early stag...
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Purpose Women with breast cancer frequently develop painful bone metastases. This retrospective study was designed to longitudinally characterize patterns of patient-reported symptoms among patients with breast cancer relative to the diagnosis of bone metastases. Methods Patient records were identified from the Oncology Services Comprehensive Elec...
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Background Telephone quitlines can help employees quit smoking. Quitlines typically use directive coaching, but nondirective, flexible coaching is an alternative. Call-2-Quit used a worksite-sponsored quitline to compare directive and nondirective coaching modes, and evaluated employee race and income as potential moderators. Methods An unblinded...
Article
Background: Extended endocrine therapy (> 5 years; EET) is recommended for many ESBC patients following the results of the MA.17, ATLAS, and aTTom clinical trials. Clinical practice guidelines recommend consideration of 10 years of endocrine therapy; however, they note the challenging risk vs benefit profile given the modest benefit of EET in terms...
Article
550 Background: Patients with KRAS WT mCRC treated with B or C plus standard chemotherapy backbones had comparable outcomes in the Phase III CALGB 80405 trial; comparative effectiveness in a real-world community setting remains unknown. Methods: This retrospective study examined PFS and OS in a US community sample of adult, KRAS WT, mCRC patients t...
Article
Background: Patients with non-small cell lung cancer (NSCLC) experience adverse physical symptoms because of cancer, cancer treatment, and comorbidities. The relations among Cancer-Related Symptoms, Functional Impairment, and Psychological Symptoms in patients with NSCLC is not well understood. Methods: Retrospective analysis of patient-reported...
Article
Although narrow eligibility criteria improve the internal validity of clinical trials, they may result in differences between study populations and real-world patients, threatening generalizability. Therefore, we evaluated whether patients treated for metastatic renal cell cancer (mRCC) in routine clinical practice are similar to those enrolled ont...
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Background: Platin-based adjuvant chemotherapy has extended survival in clinical trials in patients with completely resected non-small cell lung cancer (NSCLC). There are few data on the use of adjuvant therapy in community-based clinical practice in the United States. Materials and methods: This was a retrospective observational study using ele...
Article
Insights into the experience of metastatic renal cell carcinoma (mRCC) patients are needed to optimize patient care. A retrospective, multicenter registry of mRCC patients treated at academic (Duke) and community (ACORN) practices was developed to fill this need. Treatment data were collected on 466 patients who received first-line therapy from 200...
Article
Treatment for metastatic castrate-resistant prostate cancer in community settings is not well understood. To examine treatment patterns, sequencing, and outcomes in patients receiving second- and third-line treatment after first-line docetaxel. We used a community oncology database to identify patients who progressed after line 1 docetaxel (D) and...
Article
Background: The association of race with clinical outcomes has been increasingly investigated in non-small cell lung cancer (NSCLC). This prospective observational study evaluated the impact of race on disease control rate (DCR) in patients with NSCLC treated with second-line pemetrexed. Our previous report of this study showed the DCR of African-A...
Article
Full-text available
Purpose: Women with breast cancer frequently develop painful bone metastases. This retrospective study was designed to longitudinally characterize patterns of patient-reported symptoms among patients with breast cancer relative to the diagnosis of bone metastases. Methods: Patient records were identified from the Oncology Services Comprehensive...
Article
Background: Second-line treatment with pemetrexed (Pem) has demonstrated safety and efficacy in NSCLC patients. A prospective observational study was conducted to evaluate the impact of race on disease control rate (DCR) in NSCLC patients treated with 2nd line Pem. This analysis focuses on the association of race with tolerability of treatment and...
Article
Treatment options for metastatic breast cancer (MBC) are complex, and some patients experience early discontinuation or switching of treatment (ETDS). We examined the relationship between ETDS and patient-reported symptom burden among patients receiving first-line treatment of MBC in community oncology settings. This retrospective observational stu...
Article
Background The primary systemic treatments for advanced melanoma have been chemotherapy and immunotherapy. New agents are currently in development. Objectives This study aimed to characterize treatment patterns and outcomes across several lines of therapy and to illustrate the treatment landscape prior to the approval of new therapies. The study en...
Article
R1507 is a human IgG1 Mab that binds to the insulin-like growth factor-1 receptor (IGF-1R) and inhibits IGF-1- or IGF-2-mediated anchorage-independent growth of malignant cells. A phase 1b study evaluated the safety, tolerability and efficacy of R1507 in combination with multiple standard oncology regimens. R1507 (3, 5, 9, 10 and 16 mg/kg IV, Q2 W...
Article
As new therapeutics for metastatic renal cell carcinoma (mRCC) are quickly introduced to market, comparative randomized trial evidence guiding treatment decisions is lacking, especially in the second treatment exposure and beyond. As a demonstration case, we studied mRCC in real-world clinical settings by creating a joint community-academic retrosp...
Article
Background Peripheral neuropathy (PN) is associated with multiple myeloma (MM) and often exacerbated by anti-MM treatments. TIPN poses significant morbidity and may result in therapy modifications. The impact of TIPN on treatment patterns and outcomes is not well studied in “real world” settings. We examined the association between TIPN in NDMM wit...
Article
118 Background: Cabazitaxel (C) and abiraterone (A) improve survival in mCRPC after progression on docetaxel (D). We examined whether mCRPC patients progressing on D received C and/or A, in which sequence, and how they compared with patients not receiving C or A. Methods: This retrospective study used medical records from the ACORN Data Warehouse....
Article
Lack of trust and rapport with health care providers has been identified in the under-representation of racial/ethnic minorities within clinical trials. Our study used a coach to promote trust among minority patients with advanced cancer. Minority patients with advanced breast, colorectal, lung, or prostate carcinoma were randomly assigned to recei...
Article
In this phase II study, we explored efficacy and toxicity of combined endocrine and low-dose metronomic chemotherapy therapy consisting of fulvestrant and capecitabine in estrogen and/or progesterone receptor-positive, HER2-negative MBC. Patients with ≤ 1 previous hormonal treatment in the metastatic setting received an injection fulvestrant loadin...
Article
Objective: Understanding the value patients place on avoiding various aspects of chemotherapy induced nausea and vomiting (CINV) can help medical professionals assess whether current and emerging treatments are acceptable based on their costs and expected effects. Little is known, however, about the value patients place on avoiding various aspects...