Cancer Biomarkers and Pharmacogenomics

Last updated on Oct 3, 2025 Collaborations
Figure 1 reproduced from Till, et al. (2025).

Biomarkers are an important tool in cancer detection, treatment, and prognosis. In these collaborations, I provide statistical expertise related to the design of experiments and the analysis of data from both prospective and retrospective studies. I highlight two particular projects of interest below.

In collaborative projects with Erica L. Carpenter, MBA, PhD, we investigate the use of non-solid biological tissue (“liquid biopsy”) – including and especially circulating tumor cells and cell-free DNA – for its capacity to provide early detection of disease or to estimate prognosis, with the aim of developing druggable targets to improve survival.

Additional collaborations with Angela M. DeMichele, MD, MSCE aim to develop and validate novel assays for dormant tumor cells (DTCs) in breast cancer patients, which are believed to be a primary vector of cancer recurrence.

Applied Cancer
Nicholas J. Seewald
Nicholas J. Seewald
Assistant Professor of Biostatistics

Assistant Professor of Biostatistics at the University of Pennsyvlania Perelman School of Medicine

Publications

LODESTAR: A single arm phase II study of rucaparib in solid tumors with pathogenic germline or somatic variants in homologous recombination repair genes

Purpose: To explore PARP inhibitor (PARPi) utility across solid tumors and identify biomarkers that predict sensitivity.

Patients and …

Sriram Anbil, Nicholas J. Seewald, E. Gabriela Chiorean, Maen Hussein, Pashtoon Murtaza Kasi, Doug E. Laux, Gary K. Schwartz, Geoffrey Shapiro, Kevin K. Lin, Marcia Craib, Lara Maloney, Karen McLachlan, Hanna Tukachinsky, Alexa B. Schrock, Shuoguo Wang, Ethan S. Sokol, Brennan Decker, Katherine L. Nathanson, Susan M. Domchek, Kim A. Reiss
Cite DOI PubMed Project
[Abstract] Circulating tumor DNA (ctDNA), dormant disseminated tumor cells (DTCs) and recurrence outcomes in breast cancer survivors on the SURMOUNT Study

Background: Recurrence after early-stage breast cancer (BC) is a challenge, occurring in ∼30% of patients (pts). Recurrences may arise …

Eleanor Taranto, Nicholas J. Seewald, Lauren J. Bayne, Emma Walinsky, Shannon Deluca, Natalie NC. Shih, Pauleen Sanchez, Isoris Nivar, Bana Ambasager, Clodagh Murray, Amber Chevalier, Christopher G. Smith, Igor Makhlin, Killian Rohn, Brooke L. Goodspeed, Jessica Savage, Paul Wileyto, Jianping Wang, George Belka, Elizabeth Chislock, Lindsay R Berry, Don Berry, Anupma Nayak, Michael Feldman, Amy S. Clark, Lewis A. Chodosh, Angela DeMichele
Cite DOI Project
Corticosteroid-dependent association between prognostic peripheral blood cell-free DNA levels and neutrophil-mediated NETosis in patients with glioblastoma

Purpose: Non-invasive prognostic biomarkers to inform clinical decision-making are an urgent unmet need for the management of patients …

Jacob E. Till, Nicholas J. Seewald, Zachariya Yazdani, Zhuoyang Wang, Dominique Ballinger, Heather Samberg, Siri Dandu, Camilla Macia, Melinda Yin, Aseel Abdalla, Timothy Prior, Shivani Shah, Thara Patel, Emily McCoy, Maikel Monsour, Carson A. Wills, Veronica Bochenek, Jonathan Serrano, Matija Snuderl, Richard E. Phillips, Donald M. O’Rourke, Nduka M. Amankulor, Ali Nabavizadeh, Arati S. Desai, Kandace Gollomp, Zev A. Binder, Wanding Zhou, Stephen J. Bagley, Erica L. Carpenter
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[Abstract] Does liver tumor morphology predict outcomes after LDT, PRRT or captem?

Background: Patients with metastatic neuroendocrine tumor (NET) have multiple options for liver-directed therapy (LDT) and systemic …

Cathal O'Leary, David Tischfield, Rony Avritscher, Ghassan El-Haddad, Nicholas Fidelman, Ricardo Garcia-Monaco, Nimrata Vijayvergia, Pamela Kunz, Nicholas J. Seewald, Michael C. Soulen
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[Abstract] Association of BRCA1/2 pathogenic variants with primary tumor location and metastatic organotropism in pancreatic adenocarcinoma

Background: Pancreatic cancers (PDACs) with BRCA1/2 pathogenic variants (PVs) are prognostically favorable and predict response to …

Ryan Hood, Srishti Rathore, Nicholas J. Seewald, Kim Anna Reiss
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[Abstract] Interaction of BRCA1 vs BRCA2 pathogenic variants with primary tumor location in pancreatic cancer

Background: BRCA1/2 germline or somatic pathogenic variants (PVs) are found in 5-10% of pancreatic adenocarcinoma (PDAC) patients. …

Ryan Hood, Nicholas J. Seewald, Srishti Rathore, Kim Anna Reiss
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Evidence for Association of SNPs in ABCB1 and CBR3, but Not RAC2, NCF4, SLC28A3 or TOP2B, with Chronic Cardiotoxicity in a Cohort of Breast Cancer Patients Treated with Anthracyclines
AIMS: Validation of associations for SNPs in RAC2, NCF4 and SLC28A3, identification of a novel association with a TOP2B SNP and …
Daniel L. Hertz, Megan v. Caram, Kelley M. Kidwell, Jacklyn N. Thibert, Christina Gersch, Nicholas J. Seewald, Jeffrey Smerage, Melvyn Rubenfire, N. Lynn Henry, Kathleen A. Cooney, Monika Leja, Jennifer J. Griggs, James M. Rae
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Polymorphisms in Drug-Metabolizing Enzymes and Steady-State Exemestane Concentration in Postmenopausal Patients with Breast Cancer
Discovery of clinical and genetic predictors of exemestane pharmacokinetics was attempted in 246 postmenopausal patients with breast …
Daniel L. Hertz, Kelley M. Kidwell, Nicholas J. Seewald, Christina L. Gersch, Zeruesenay Desta, David A. Flockhart, Ana-Maria Storniolo, Vered Stearns, Todd C. Skaar, Daniel F. Hayes, N. Lynn Henry, James M. Rae
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