About

Gregory K. Hartig is a professor and the Chief of the Division of Head and Neck Oncologic Surgery at the University of Wisconsin-Madison, where he also serves as the Head and Neck Oncology and Microvascular Reconstructive Surgery Fellowship Program Director. He holds an MD from the University of Michigan and has completed internships, residencies, and a fellowship in Head and Neck Reconstructive Surgery at prominent institutions including the University of Michigan and the University of Pennsylvania Medical Center. Certified by the American Board of Otolaryngology-Head and Neck Surgery, Dr. Hartig's practice combines traditional head and neck surgery with facial plastic and reconstructive surgery, with extensive experience managing head and neck cancer, including tumors of the skull base, and performing microvascular free tissue transfer reconstruction. He directs the head and neck oncology program at UW Hospital and Clinics, providing a wide range of surgical services such as airway reconstruction, laryngeal surgery, laser procedures, maxillofacial trauma repair, and transoral robotic surgery. His research interests include the cytogenetics of head and neck carcinoma, free flap physiology, airway reconstruction, and evaluating risk factors for salivary gland tumors and malignancies. Dr. Hartig is involved with the UW Head and Neck Cancer SPORE, contributing to projects on therapeutic combinations for cancer treatment.

Research topics

• Surgery
• Medicine
• Nuclear medicine
• Oncology
• Internal medicine

Selected publications

• Survival outcomes of locoregionally advanced papillary thyroid carcinoma

  International Journal of Otorhinolaryngology and Head and Neck Surgery · 2025-07-25

  articleOpen access

  Background: PTC carries an overall excellent prognosis. Most patients with PTC have small and asymptomatic disease. This raises the question whether overall rates overestimate the survival of those with advanced disease. We use our institutional data to report disease-free and overall survival of patients with locoregionally advanced PTC. Methods: A retrospective study of 92 patients who underwent a total thyroidectomy from 2002 to 2019 at a single institution. Features of locoregionally advanced disease were defined as extra thyroid extension, primary tumor size ≥4 cm, or cervical nodal involvement. These and additional clinical and histological features were analyzed for association with recurrence and disease-free survival. Results: Twenty-six patients had recurrence of disease. Patients with ETE, nonspecific cervical nodal involvement, or tumor size ≥4 cm had no significant increase in recurrence (p=0.2554, 0.1886, 0.2278, respectively). Patients with nodal metastasis to lateral neck compartment had a significant increase in recurrence (p=0.0434). 5-year overall survival was 95%. Conclusion: PTC has an excellent prognosis even in the presence of advanced locoregional disease. However, lateral neck nodal involvement is associated with higher rates of recurrence and may be an indicator for more aggressive management.

  PublisherOA PDFDOI

• Safety and toxicity of Iopofosine I 131 (CLR 131) with external beam radiation therapy in recurrent or metastatic head and neck cancer: results of a phase 1 single-centre, open-label, single-arm, dose escalation and dose expansion study

  EBioMedicine · 2024-12-12 · 3 citations

  articleOpen access

  BACKGROUND: Re-irradiation of recurrent head and neck cancer (HNC) is often limited by tumour adherence to critical structures and/or radiation tolerance of critical normal tissues. Iopofosine I 131 (CLR 131) is a targeted small molecular phospholipid ether (PLE) drug conjugate that delivers iodine-131 selectively to tumour cells. We conducted a phase 1, single-centre, open-label study to determine whether CLR 131 given with reduced dose of external beam radiation therapy (EBRT) would be tolerable and feasible. METHODS: All participants received previous curative intent treatment with radiotherapy as primary or adjuvant treatment. Eligible participants demonstrated uptake of CLR 131 as indicated via single photon emission CT/CT (SPECT/CT) imaging following CLR 131 test dose. Participants received two therapeutic doses of CLR 131 (days 1 and 8) with SPECT/CT imaging performed to quantitate the biodistribution of CLR 131. Participants subsequently received EBRT to achieve the designated radiation dose (60-70 Gy). The primary endpoint was safety. This trial was registered with ClinicalTrials.gov, NCT04105543, and enrolment and follow-up are complete. FINDINGS: Twelve participants completed treatment with CLR 131 and EBRT. Eight participants experienced grade 4 non-DLT haematologic toxicities (2 anaemia, 8 leukopenia, 5 thrombocytopenia) at least probably attributed to CLR 131, consistent with the expected toxicity profile. Haematologic toxicities occurred during weeks 6-8 from the first dose of CLR 131 and resolved within three weeks without sequelae. There were no treatment-related grade 3-4 non-haematologic toxicities. INTERPRETATION: CLR 131 in combination with EBRT did not confer any safety concerns, and was tolerable in participants with recurrent/metastatic HNC. Myelosuppression was consistent with the known toxicity profile of CLR 131. FUNDING: National Institutes of HealthP50 DE026787, National Cancer InstituteP30 CA014520, National Institutes of Health1UL1TR002373, Cellectar, NCT04105543.

  PublisherDOI

• Imatinib plus Cetuximab as a Window of Opportunity Clinical Trial in Head and Neck Cancer

  International Journal of Radiation Oncology*Biology*Physics · 2024-03-14 · 1 citations

  article
  PublisherDOI

• From Bench to Bedside: A Team’s Approach to Multidisciplinary Strategies to Combat Therapeutic Resistance in Head and Neck Squamous Cell Carcinoma

  Journal of Clinical Medicine · 2024-10-10 · 7 citations

  reviewOpen access

  Head and neck squamous cell carcinoma (HNSCC) is diagnosed in more than 71,000 patients each year in the United States, with nearly 16,000 associated deaths. One significant hurdle in the treatment of HNSCC is acquired and intrinsic resistance to existing therapeutic agents. Over the past several decades, the University of Wisconsin has formed a multidisciplinary team to move basic scientific discovery along the translational spectrum to impact the lives of HNSCC patients. In this review, we outline key discoveries made throughout the years at the University of Wisconsin to deepen our understanding of therapeutic resistance in HNSCC and how a strong, interdisciplinary team can make significant advances toward improving the lives of these patients by combatting resistance to established therapeutic modalities. We are profoundly grateful to the many scientific teams worldwide whose groundbreaking discoveries, alongside evolving clinical paradigms in head and neck oncology, have been instrumental in making our work possible.

  PublisherOA PDFDOI

• Interstitial Brachytherapy for Lip Cancer: Technical Aspects to Individualize Treatment Approach and Optimize Outcomes

  Practical Radiation Oncology · 2023-01-25 · 6 citations

  articleOpen access
  PublisherOA PDFDOI

• Data from Radiosensitization of Adenoid Cystic Carcinoma with MDM2 Inhibition

  2023-03-31

  preprintOpen access

  <div>Abstract<p><b>Purpose:</b> Adenoid cystic carcinoma (ACC) is a rare cancer arising from the major or minor salivary gland tissues of the head and neck. There are currently no approved systemic agents or known radiosensitizers for ACC. Unlike the more common head and neck squamous cell carcinomas that frequently harbor TP53 mutations, ACCs contain TP53 mutations at a rate of <5%, rendering them an attractive target for MDM2 inhibition.</p><p><b>Experimental Design:</b> We report the successful establishment and detailed characterization of a TP53-WT ACC patient-derived xenograft (PDX), which retained the histologic features of the original patient tumor. We evaluated this model for response to the MDM2 inhibitor AMG 232 as monotherapy and in combination with radiotherapy.</p><p><b>Results:</b> AMG 232 monotherapy induced modest tumor growth inhibition, and radiation monotherapy induced a transient tumor growth delay in a dose-dependent fashion. Strikingly, combination treatment of AMG 232 with radiotherapy (including low-dose radiotherapy of 2 Gy/fraction) induced dramatic tumor response and high local tumor control rates 3 months following treatment. Posttreatment analysis revealed that although both AMG 232 and radiotherapy alone induced TP53 tumor-suppressive activities, combination therapy amplified this response with potent induction of apoptosis after combination treatment.</p><p><b>Conclusions:</b> These data identify that MDM2 inhibition can provide potent radiosensitization in TP53-WT ACC. In light of the absence of effective systemic agents for ACC, the powerful response profile observed here suggests that clinical trial evaluation of this drug/radiotherapy combination may be warranted to improve local control in this challenging malignancy. <i>Clin Cancer Res; 23(20); 6044–53. ©2017 AACR</i>.</p></div>

  PublisherDOI

• Supplementary Figure 1 from Development and Characterization of HPV-Positive and HPV-Negative Head and Neck Squamous Cell Carcinoma Tumorgrafts

  2023-03-31

  preprintOpen access

  <p>PDF file - 384K, Detection of multiple HPV subtypes by degenerate PCR of genomic DNA (A) or by HPV-16 specific Southern blot (B).</p>

  PublisherOA PDFDOI

• Supplementary Table 1 from Development and Characterization of HPV-Positive and HPV-Negative Head and Neck Squamous Cell Carcinoma Tumorgrafts

  2023-03-31

  supplementary-materialsOpen access

  <p>XLSX file - 37K, Primer sequences used.</p>

  PublisherDOI

• Supplementary Figure 1 from Development and Characterization of HPV-Positive and HPV-Negative Head and Neck Squamous Cell Carcinoma Tumorgrafts

  2023-03-31

  preprintOpen access

  <p>PDF file - 384K, Detection of multiple HPV subtypes by degenerate PCR of genomic DNA (A) or by HPV-16 specific Southern blot (B).</p>

  PublisherDOI

• Data from Development and Characterization of HPV-Positive and HPV-Negative Head and Neck Squamous Cell Carcinoma Tumorgrafts

  2023-03-31

  preprintOpen access

  <div>Abstract<p><b>Purpose:</b> To develop a clinically relevant model system to study head and neck squamous cell carcinoma (HNSCC), we have established and characterized a direct-from-patient tumorgraft model of human papillomavirus (HPV)–positive and HPV-negative cancers.</p><p><b>Experimental Design:</b> Patients with newly diagnosed or recurrent HNSCC were consented for donation of tumor specimens. Surgically obtained tissue was implanted subcutaneously into immunodeficient mice. During subsequent passages, both formalin-fixed/paraffin-embedded as well as flash-frozen tissues were harvested. Tumors were analyzed for a variety of relevant tumor markers. Tumor growth rates and response to radiation, cisplatin, or cetuximab were assessed and early passage cell strains were developed for rapid testing of drug sensitivity.</p><p><b>Results:</b> Tumorgrafts have been established in 22 of 26 patients to date. Significant diversity in tumorgraft tumor differentiation was observed with good agreement in degree of differentiation between patient tumor and tumorgraft (Kappa 0.72). Six tumorgrafts were HPV-positive on the basis of p16 staining. A strong inverse correlation between tumorgraft p16 and p53 or Rb was identified (Spearman correlations <i>P</i> = 0.085 and <i>P</i> = 0.002, respectively). Significant growth inhibition of representative tumorgrafts was shown with cisplatin, cetuximab, or radiation treatment delivered over a two-week period. Early passage cell strains showed high consistency in response to cancer therapy between tumorgraft and cell strain.</p><p><b>Conclusions:</b> We have established a robust human tumorgraft model system for investigating HPV-positive and HPV-negative HNSCC. These tumorgrafts show strong correlation with the original tumor specimens and provide a powerful resource for investigating mechanisms of therapeutic response as well as preclinical testing. <i>Clin Cancer Res; 19(4); 855–64. ©2012 AACR</i>.</p></div>

  PublisherDOI

Frequent coauthors

• Paul M. Harari

  University of Wisconsin Carbone Cancer Center

  91 shared

• Randall J. Kimple

  45 shared

• Aaron M. Wieland

  44 shared

• Timothy M. McCulloch

  University of Wisconsin–Madison

  42 shared

• Justine Y. Bruce

  University of Wisconsin–Madison

  22 shared

• Nadine P. Connor

  University of Wisconsin–Madison

  20 shared

• Matthew E. Witek

  18 shared

• Irene M. Ong

  University of Wisconsin–Madison

  16 shared

Awards & honors

• Castle Connolly America’s Top Doctors, Otolaryngology
• Best Doctors in America Award, Otolaryngology
• Madison Magazine Top Docs 2016 Award, Otolaryngology