About

Lillias H. Maguire, MD, is an Assistant Professor of Surgery at the University of Pennsylvania's Perelman School of Medicine. She is an active surgeon affiliated with Pennsylvania Hospital, Penn Presbyterian Medical Center, and the Cpl. Michael J. Crescenz Veterans Affairs Medical Center in Philadelphia, PA. Dr. Maguire specializes in minimally invasive colorectal surgery, rectal cancer surgery, inflammatory bowel disease, robotic surgery, colonoscopy, and anorectal surgery. Her research focuses on translational genomics in colorectal diseases, including clinical trials, genome-wide association studies, and surgical grantsmanship. She has contributed to studies on diverticulitis, pilonidal disease, and the genetic factors associated with diverticular disease. Dr. Maguire has authored multiple publications in her field, emphasizing her active engagement in advancing colorectal surgery and genomics research.

Research topics

• Medicine
• Surgery
• Internal medicine
• General surgery
• Biology

Selected publications

• Mature Tertiary Lymphoid Structures in Pilonidal Sinus Disease

  JID Innovations · 2026-04-01

  articleOpen access
  PublisherDOI

• Grantsmanship Refined: Evaluation and Training of Efficacy in Residents (Greater Study)

  Journal of surgical education · 2026-02-25

  articleSenior author
  PublisherDOI

• Genome-wide association meta-analysis identifies 126 novel loci for diverticular disease and implicates connective tissue and colonic motility

  medRxiv · 2025-03-28 · 2 citations

  preprintOpen accessSenior author

  Diverticular disease is a common and morbid complex phenotype influenced by both innate and environmental risk factors. We performed the largest genome-wide association study meta-analysis for diverticular disease, identifying 126 novel loci. Employing multiple downstream analytic strategies, including tissue and pathway enrichment, statistical fine-mapping, allele-specific expression, protein quantitative trait loci and drug-target investigations, and linkage disequilibrium score regression, we prioritized causal genes and produced several lines of evidence linking diverticular disease to connective tissue biology and colonic motility. We substantiated these findings by integrating single-cell RNA sequencing data, showing that prioritized diverticular disease-associated genes are enriched for expression in colonic smooth muscle, fibroblasts, and interstitial cells of Cajal. In quantitative analysis of surgical specimens, we found a substantial reduction in the density of elastin present in the sigmoid colon in severe diverticulitis.

  PublisherDOI

• Novel polygenic risk score associates with diverticulitis in a multi-institutional, ancestrally diverse cohort

  Scientific Reports · 2025-11-27 · 1 citations

  articleOpen accessSenior author

  Diverticulitis is a common and morbid colorectal disease that recurs after an initial attack in up to 30% of patients. Elective surgery to remove the affected portion of the colon is an effective intervention to prevent disease recurrence, but appropriate patient selection is challenging given the limited ability to predict which patients are likely to recur, or the severity with which they may do so. Genetics influence diverticulitis and can be used for risk stratification, but this has only been studied in European ancestry populations. Using state-of-the-art techniques, we created a polygenic risk score that associates with diverticulitis prevalence and severity and is externally validated on meta-analysis in a diverse patient population across three different biobanks. This work represents the first published diverticulitis polygenic score to demonstrate utility in associating specifically with diverticulitis in non-European populations, and may provide the basis for clinical implementation in elective surgical decision-making.

  PublisherOA PDFDOI

• Lifestyle factors, genetic susceptibility and risk of incident diverticulitis: an integrated analysis of four prospective cohort studies and electronic health records-linked biobank

  Gut · 2025-07-01 · 5 citations

  articleOpen access

  BACKGROUND: Both lifestyle factors and genetic predisposition contribute to the development of diverticulitis. OBJECTIVE: To examine whether lifestyle modification can reduce the genetic risk of diverticulitis. DESIGN: We derived an overall healthy lifestyle score for diverticulitis based on smoking, body mass index (BMI), physical activity, fibre and red meat among 179 564 participants in three prospective cohorts-the Nurses' Health Study (NHS), NHSII and the Health Professionals Follow-Up Study. The association between the healthy lifestyle score and incident diverticulitis was confirmed among 30 750 participants in the Southern Community Cohort Study (SCCS). We assessed genetic risk using a polygenic risk score among 36 077 individuals with genotype data available. We further validated our findings in the Mass General Brigham Biobank (MGBB). RESULTS: A healthy lifestyle score was associated with a decreased risk of diverticulitis. Compared with a score of 0, the multivariable-adjusted HR for a score of 5 was 0.50 (95% CI, 0.44 to 0.57; p trend<0.0001). This association was consistent across the SCCS in both non-Hispanic black and white populations. Each unit increase in the healthy lifestyle score was associated with a reduced diverticulitis risk similarly across genetic risk categories, with HRs of 0.89 (95% CI, 0.83 to 0.95) for low, 0.86 (0.81 to 0.92) for mid and 0.87 (0.83 to 0.91) for high genetic risk. In the MGBB cohort, a higher BMI was associated with an increased diverticulitis risk across genetic risk categories. CONCLUSION: Maintaining a healthy lifestyle was associated with a reduced risk of developing diverticulitis, regardless of population differences and genetic susceptibilities.

  PublisherOA PDFDOI

• Appraising a CREATEive Surgeon-Scientist Initiative: Impact and Future Directions

  Diseases of the Colon & Rectum · 2025-03-04

  articleCorresponding
  PublisherDOI

• Plasma Proteomic Signatures for Diverticulitis Risk Stratification

  Journal of Surgical Research · 2025-08-23

  articleOpen access

  INTRODUCTION: Approaches for risk stratification in diverticulitis have emphasized lifestyle factors, with a possible emerging role for molecular signatures. We aimed to evaluate whether plasma proteomic profiles complement dietary and genetic factors in diverticulitis risk stratification. MATERIALS AND METHODS: This UK Biobank study derived a plasma proteomic risk score for severe diverticulitis (operative or recurrent inpatient disease). The cohort was split into a training set for derivation and an independent testing set for evaluation. Differential expression and gene set enrichment analysis identified pathway-level differences, while least absolute shrinkage and selector operator models calculated the score. To evaluate utility in stratification, the proteomic risk score was included in Cox regression models with demographics, lifestyle factors, and genetic risk. A phenome-wide association study explored for conditions associated with diverticulitis proteomic signatures. RESULTS: Among 43,539 patients and 1459 plasma proteins measured at enrollment, there were 551 cases of severe diverticulitis throughout follow-up. Differential expression analysis implicated extracellular matrix and neuronal pathways, while least absolute shrinkage and selector operator regression retained 151 proteins. This proteomic risk score was associated with greater risk of severe diverticulitis (hazard ratio [95% confidence interval], 1.48 [1.18-1.87]), and a full model with proteomic and genetic factors improved upon a base model with demographic and lifestyle factors (maximum at 5-y area under the receiver operating characteristics curve [95% confidence interval], training set: 0.83 [0.79-0.86] versus 0.69 [0.64-0.73]; testing set 0.75 versus 0.70; P < 0.01) In the phenome-wide association study, elevated proteomic risk for diverticulitis was associated with renal dysfunction and cardiometabolic traits. CONCLUSIONS: Plasma proteomic profiles complemented genetic and lifestyle factors in diverticulitis risk stratification.

  PublisherOA PDFDOI

• Genetic and biologic risk factors associated with hernia formation: A review

  The American Journal of Surgery · 2024-02-27 · 9 citations

  review
  PublisherDOI

• Structural Alterations in Diverticular Disease

  Clinics in Colon and Rectal Surgery · 2024-10-10

  reviewOpen accessSenior author

  Clinicians appreciate the structural alterations of diverticular disease when navigating narrow, angulated colons with a colonoscope or removing stiff, fixed sigmoid colons at surgery. Investigation of these tissues reveals increased thickness of smooth muscle, alterations in the amount and structure of the extracellular matrix, and changes to the motility of the colon. More sophisticated technologies now allow scientists to unravel the connections between these alterations and the individual genetic background. This article explores the structural alterations of diverticular disease including collagen, smooth muscle, the enteric nervous system, and the interstitial cells of Cajal.

  PublisherOA PDFDOI

• Resident Self-Efficacy in Grantsmanship Lags Behind Key Funding Deadlines

  Journal of surgical education · 2024-10-07 · 1 citations

  articleSenior author
  PublisherDOI

Recent grants

• Genetic Determinants of Outcomes in Diverticular Disease

  NIH · $671k · 2020–2026

• Genetic Determinants of Outcomes in Diverticular Disease

  NIH · $170k · 2020–2025

Frequent coauthors

• Jeffrey L. Roberson

  Hospital of the University of Pennsylvania

  11 shared

• Scott E. Regenbogen

  University of Michigan–Ann Arbor

  10 shared

• Alexander T. Hawkins

  Vanderbilt University

  8 shared

• Yash Hegde

  Shamnur Shivashankarappa Institute of Medical Sciences & Research Centre

  8 shared

• Elizabeth K. Speliotes

  Michigan Medicine

  7 shared

• Scott M. Damrauer

  7 shared

• Andrew T. Chan

  Brigham and Women's Hospital

  7 shared

• Samantha Hendren

  University of Michigan–Ann Arbor

  6 shared

Labs

• Maguire LabPI

Education

• MD

  University of Pennsylvania

  2008