About

Merrick Anderson is an Assistant Professor of Philosophy at USC Dornsife. His professional role involves teaching and research within the philosophy department, contributing to the academic community through his scholarly activities. Specific details about his research focus, background, or key contributions are not provided in the page text.

Research topics

• Medicine
• Genetics
• Computer Science
• Internal medicine
• Biology
• Bioinformatics
• Surgery
• Data science
• Computational biology
• Cancer research
• Oncology

Selected publications

• A PROSPECTIVE 2 YEAR REVIEW OF LYMPHEDEMA RATES IN BREAST CANCER PATIENTS FOLLOWING MASTECTOMY, AXILLARY CLEARANCE, AND IMMEDIATE FREE FLAP BREAST RECONSTRUCTION

  Lymphology · 2025-04-16

  articleOpen access1st authorCorresponding

  The reported incidence of lymphedema varies greatly among women treated for breast cancer, making counselling for surgery challenging. This study assessed the incidence of lymphedema in patients undergoing mastectomy and free flap reconstruction using robust, quantifiable, and replicable diagnostic criteria. Data on limb circumference, limb volume, and reported symptoms was collected prospectively pre-operatively, post operatively, and at 2 years. All patients undergoing skin sparing mastectomy with axillary node clearance and immediate free tissue breast reconstruction between 2009 and 2018 were included. We followed 113 patients to 2-year follow-up. The prevalence of patients meeting two identifying criteria was highest in the immediate post-operative period at 11%, falling to 4% at 2 years. The proportion of patients meeting three criteria remained static from the post-operative period to two years at 7%, though the incidence declined over that period. All the patients with three identifying criteria post-operatively and at two years had received either chemotherapy or chemotherapy and radiotherapy. Clear diagnostic criteria are important for the accurate assessment and study of post operative lymphedema. It is possible that free tissue transfer could reduce the incidence of or delays the onset of lymphedema in patients undergoing mastectomy and axillary clearance.

  PublisherOA PDFDOI

• P103: Operationalizing structured curated scientific literature (CIViC and Hypothesis) in developing gene-specific recommendations of the ClinGen VHL Variant Curation Expert Panel

  Genetics in Medicine Open · 2024-01-01

  articleOpen access

  Von Hippel-Lindau (VHL) disease is a hereditary tumor predisposition syndrome caused by variants in the VHL gene and has an incidence of ∼1/36,000. The Clinical Genome Resource (ClinGen) VHL Variant Curation Expert Panel (VCEP) recently specified ACMG evidence codes for VHL and aims to be an approved expert panel. The VHL VCEP is unique in that it has two large structured sets of VHL scientific literature curated through other efforts: Clinical Interpretation of Variants in Cancer (CIViC, www.civicdb.org) with >630 VHL variants representing >428 papers, and Hypothesis (web.hypothes.is) with >8700 structured annotations from VHL clinical literature.

  PublisherOA PDFDOI

• Prevalence of disclosed and undisclosed financial conflicts of interest among systematic review authors regarding the management of proximal humerus fractures

  2024-01-30

  preprintOpen access

  Background: A systematic review is an important evidence synthesis technique used to collate results from individual studies, such as treatments for proximal humerus fractures. Therefore it is necessary to minimize bias in systematic reviews, including financial COIs. Financial bias has been shown to result in unreliable assessments of credibility, which is why transparency with COI is essential for accurate assessments of research. Objective: The aim of this study was to characterize the influence of financial bias on the results and conclusions of systematic reviews of proximal humerus fracture treatments and to characterize the nature of disclosed and undisclosed COIs. Methods: Ovid MEDLINE and Ovid Embase databases were searched to locate systematic reviews covering proximal humerus fracture treatments. Following these searches, title and abstract screening was performed in a duplicate, masked fashion. Data from the final reviews were extracted in a triplicate manner. The data included: PubMed ID and/or DOI; journal; publication date; author names; affiliations; interventions; funding source; risk of bias assessment/statement; whether systematic review author(s) on any of the primary studies; the articles primary outcome; whether an overall pooled effect estimate was calculated; pooled effect estimate; type of pooled effect estimate/significance; the primary outcomes favorability of pooled effect estimate; and favorability of narrative results/conclusions. All authors of each systematic review were screened for non-disclosed COIs. Results: We found no relationship between authorial COI and the results and conclusions of the systematic reviews. Among the 17 included systematic reviews, 7 (41.2%) had at least one non-disclosed COI. Of the 7 reviews with a non-disclosed COI, 2 (28.6%) were found to have a high risk of bias. Conclusions: Findings from this study have limited generalizability due to our small sample size. More studies are needed to fully elucidate the effect of financial bias on the results and conclusions of systematic reviews.

  PublisherOA PDFDOI

• Specifications of the ACMG/AMP variant curation guidelines for the analysis of germline ATM sequence variants

  The American Journal of Human Genetics · 2024-09-23 · 14 citations

  articleOpen access

  The ClinGen Hereditary Breast, Ovarian, and Pancreatic Cancer (HBOP) Variant Curation Expert Panel (VCEP) is composed of internationally recognized experts in clinical genetics, molecular biology, and variant interpretation. This VCEP made specifications for the American College of Medical Genetics and Association for Molecular Pathology (ACMG/AMP) guidelines for the ataxia telangiectasia mutated (ATM) gene according to the ClinGen protocol. These gene-specific rules for ATM were modified from the ACMG/AMP guidelines and were tested against 33 ATM variants of various types and classifications in a pilot curation phase. The pilot revealed a majority agreement between the HBOP VCEP classifications and the ClinVar-deposited classifications. Six pilot variants had conflicting interpretations in ClinVar, and re-evaluation with the VCEP's ATM-specific rules resulted in four that were classified as benign, one as likely pathogenic, and one as a variant of uncertain significance (VUS) by the VCEP, improving the certainty of interpretations in the public domain. Overall, 28 of the 33 pilot variants were not VUS, leading to an 85% classification rate. The ClinGen-approved, modified rules demonstrated value for improved interpretation of variants in ATM.

  PublisherOA PDFDOI

• Surface wear of PyroCarbon implant in metacarpophalangeal joint arthroplasty without radiographic abnormality: A case report

  Hand surgery & rehabilitation · 2024-04-05

  article
  PublisherDOI

• Specifications of the ACMG/AMP variant curation guidelines for the analysis of germline <i>ATM</i> sequence variants

  medRxiv · 2024-05-29 · 2 citations

  preprintOpen access

  Abstract The ClinGen Hereditary Breast, Ovarian and Pancreatic Cancer (HBOP) Variant Curation Expert Panel (VCEP) is composed of internationally recognized experts in clinical genetics, molecular biology and variant interpretation. This VCEP made specifications for ACMG/AMP guidelines for the ataxia telangiectasia mutated ( ATM ) gene according to the Food and Drug Administration (FDA)-approved ClinGen protocol. These gene-specific rules for ATM were modified from the American College of Medical Genetics and Association for Molecular Pathology (ACMG/AMP) guidelines and were tested against 33 ATM variants of various types and classifications in a pilot curation phase. The pilot revealed a majority agreement between the HBOP VCEP classifications and the ClinVar-deposited classifications. Six pilot variants had conflicting interpretations in ClinVar and reevaluation with the VCEP’s ATM -specific rules resulted in four that were classified as benign, one as likely pathogenic and one as a variant of uncertain significance (VUS) by the VCEP, improving the certainty of interpretations in the public domain. Overall, 28 the 33 pilot variants were not VUS leading to an 85% classification rate. The ClinGen-approved, modified rules demonstrated value for improved interpretation of variants in ATM .

  PublisherOA PDFDOI

• Supplementary Figure 3 from Mouse Mesenchymal Stem Cells Expressing PAX-FKHR Form Alveolar Rhabdomyosarcomas by Cooperating with Secondary Mutations

  2023-03-30

  preprintOpen accessSenior author

  Supplementary Figure 3 from Mouse Mesenchymal Stem Cells Expressing PAX-FKHR Form Alveolar Rhabdomyosarcomas by Cooperating with Secondary Mutations

  PublisherOA PDFDOI

• Retrospective Cohort Study on the Limitations of Direct-to-Consumer Genetic Screening in Hereditary Breast and Ovarian Cancer

  JCO Precision Oncology · 2023-08-01 · 4 citations

  articleOpen access

  PURPOSE Among cancer predisposition genes, most direct-to-consumer (DTC) genetic tests evaluate three Ashkenazi Jewish (AJ) founder mutations in BRCA1/2, which represent a small proportion of pathogenic or likely pathogenic variants (PLPV) in cancer predisposing genes. In this study, we investigate PLPV in BRCA1/2 and other cancer predisposition genes that are missed by testing only AJ founder BRCA1/2 mutations. METHODS Individuals were referred to genetic testing for personal diagnoses of breast and/or ovarian cancer (clinical cohort) or were self-referred (nonindication-based cohort). There were 348,692 participants in the clinical cohort and 7,636 participants in the nonindication-based cohort. Both cohorts were analyzed for BRCA1/2 AJ founder mutations. Full sequence analysis was done for PLPV in BRCA1/2, CDH1, PALB2, PTEN, STK11, TP53, ATM, BARD1, BRIP1, CHEK2 (truncating variants), EPCAM, MLH1, MSH2/6, NF1, PMS2, RAD51C/D, and 22 other genes. RESULTS BRCA1/2 AJ founder mutations accounted for 10.8% and 29.7% of BRCA1/2 PLPV in the clinical and nonindication-based cohorts, respectively. AJ founder mutations accounted for 89.9% of BRCA1/2 PLPV in those of full AJ descent, but only 69.6% of those of partial AJ descent. In total, 0.5% of all individuals had a BRCA1/2 AJ founder variant, while 7.7% had PLPV in a high-risk breast/ovarian cancer gene. For non-AJ individuals, limiting evaluation to the AJ founder BRCA1/2 mutations missed &gt;90% of mutations in actionable cancer risk genes. Secondary analysis revealed a false-positive rate of 69% for PLPV outside of non-AJ BRCA 1/2 founder mutations. CONCLUSION DTC genetic testing misses &gt;90% of BRCA1/2 PLPV in individuals of non-AJ ancestry and about 10% of BRCA1/2 PLPV among AJ individuals. There is a high false-positivity rate for non-AJ BRCA 1/2 PLPV with DTC genetic testing.

  PublisherOA PDFDOI

• Zone I Revision Finger Amputations Performed in the Emergency Department Compared With Those Performed in the Operating Room

  Orthopedics · 2023-11-03 · 1 citations

  article1st authorCorresponding

  Finger amputations are commonly encountered. These may be revised in the emergency department (ED) or the operating room (OR). Previous studies have demonstrated the cost-effectiveness associated with procedures performed in the ED. Patient outcomes have not been described. We retrospectively reviewed patients who presented to our level 1 trauma center with a traumatic partial or complete finger amputation through flexor tendon zone I. All were treated with revision amputation performed in either the ED or the OR between January 2012 and December 2017. A total of 172 patient charts were included. Ninety-three of the revision amputations were performed in the ED, while 79 were performed in the OR. There was no difference in age, race, sex, having a manual labor job, medical comorbidities, or mechanism of injury between the groups. Compared with procedures performed in the ED, procedures performed in the OR had a higher rate of delayed healing, a longer stay in the hospital, and a higher referral to therapy postoperatively. Length of follow-up and number of follow-up visits were not statistically different based on location of procedure. There was no difference in post-procedural infection rate or need for revision procedure between the groups. Our data support the efficacy of performing revision amputation procedures in the ED. Recorded patient complications and subsequent treatment after revision amputations performed in the ED vs the OR were comparable. Those performed in the ED potentially decrease the burden placed on the patient and the health care system. [ Orthopedics . 2024;47(3):152–156.]

  PublisherDOI

• Data from Mouse Mesenchymal Stem Cells Expressing PAX-FKHR Form Alveolar Rhabdomyosarcomas by Cooperating with Secondary Mutations

  2023-03-30

  preprintOpen accessSenior author

  &lt;div&gt;Abstract&lt;p&gt;Alveolar rhabdomyosarcomas (ARMS) are highly malignant soft-tissue sarcomas that arise in children, adolescents, and young adults. Although formation and expression of the &lt;i&gt;PAX-FKHR&lt;/i&gt; fusion genes is thought to be the initiating event in this cancer, the role of PAX-FKHR in the neoplastic process remains largely unknown in a progenitor cell that is undefined. We hypothesize that PAX-FKHR determine the ARMS progenitor to the skeletal muscle lineage, which when coupled to the inactivation and/or activation of critical cell signaling pathways leads to the formation of ARMS. Because a number of studies have proposed that mesenchymal stem cells (MSC) are the progenitor for several of the sarcomas, we tested this hypothesis in MSCs. We show that PAX-FKHR induce skeletal myogenesis in MSCs by transactivating MyoD and myogenin. Despite exhibiting enhanced growth &lt;i&gt;in vitro&lt;/i&gt;, the PAX-FKHR–expressing populations do not form colonies in soft agar or tumors in mice. Expression of dominant-negative p53, or the SV40 early region, elicits tumor formation in some of the PAX-FKHR–expressing populations. Additional activation of the Ras signaling pathway leads to highly malignant tumor formation for all of the populations. The PAX-FKHR–expressing tumors were shown to have histologic, immunohistochemical, and gene expression profiles similar to human ARMS. Our results show the critical role played by PAX-FKHR in determining the molecular, myogenic, and histologic phenotype of ARMS. More importantly, we identify MSCs as a progenitor that can give rise to ARMS. [Cancer Res 2008;68(16):6587–97]&lt;/p&gt;&lt;/div&gt;

  PublisherDOI

Frequent coauthors

• David W. Denning

  University of Manchester

  47 shared

• Timothy J. Triche

  Children's Hospital of Los Angeles

  22 shared

• Jonathan D. Buckley

  Keele University

  16 shared

• Mike Birch

  15 shared

• Friedrich Graf Finckenstein

  12 shared

• Paul Bowyer

  University of Manchester

  11 shared

• Elai Davicioni

  10 shared

• Karen C. Arden

  Ludwig Cancer Research

  10 shared