William Joseph Chapin, MD, MSCE
Assistant Professor of Medicine (Hematology-Oncology) at the Hospital of the University of Pennsylvania
Department: Medicine
Contact information
Perelman Center for Advanced Medicine
10 South Pavilion
3400 Civic Center Blvd
Philadelphia, PA 19104
10 South Pavilion
3400 Civic Center Blvd
Philadelphia, PA 19104
Education:
BS (Molecular Biology, Spanish, Honors in the Liberal Arts)
University of Wisconsin-Madison , 2012.
MD (Medicine )
The University of Chicago Pritzeker School of Medicine , 2016.
MSCE (Clinical Epidemiology)
University of Pennsylvania Perelman School of Medicine , 2022.
Permanent linkBS (Molecular Biology, Spanish, Honors in the Liberal Arts)
University of Wisconsin-Madison , 2012.
MD (Medicine )
The University of Chicago Pritzeker School of Medicine , 2016.
MSCE (Clinical Epidemiology)
University of Pennsylvania Perelman School of Medicine , 2022.
Selected Publications
Lin JK, Niu J, Giordano SH, Li P, Snyder RA, Liao K, Li M, Aparicio A, Chapin W, Zhang J, Xiang J, Perera N, Pain D, Guerra CE, Doshi JA.: Racial and Ethnic Disparities Along the Treatment Cascade Among Medicare Fee-for-Service Beneficiaries With Metastatic Breast, Colorectal, Lung, and Prostate Cancers. J Clin Oncol Aug 2025.Swami N, Hwang WT, Mamtani R, O'Hara MH, Chapin WJ.: Second-Line Treatment Strategies for Right-Sided, RAS/RAF Wild-Type Colorectal Cancer. JAMA Netw Open 8: e2515087, Jun 2025.
Swami N, Hwang WT, O’Hara MH, Chapin WJ. : Real-world evaluation of a “hyperselection” predictive biomarker for anti-EGFR therapy benefit in patients with RAS/RAF wild-type, MMRp/MSS mCRC. J Clin Oncol 43(16), May 2025 Notes: Swami N, Hwang WT, O’Hara MH, Chapin WJ. Real-world evaluation of a “hyperselection” predictive biomarker for anti-EGFR therapy benefit in patients with RAS/RAF wild-type, MMRp/MSS mCRC. J Clin Oncol. 2025;43(16_suppl):e15591-e15591. doi:10.1200/JCO.2025.43.16_suppl.e15591.
Nishwant Swami , Wei-Ting Hwang , Ronac Mamtani , Mark O'Hara , William Chapin: Real-world survival comparison of second-line treatment strategies for patients with RAS/RAF wild-type, right-sided metastatic colorectal cancer. Journal of Clinical Oncology 43(4_suppl): 73, Jan 2025.
Margalit O, Stemmer A, Chapin WJ, Schacham-Shmueli E, Kopetz S, Andre T, Overman MJ, Pietrantonio F, Boursi B: Duration of Immunotherapy in dMMR/MSI-H Metastatic Colorectal Cancer Patients. European Journal of Cancer 212: 114336, Nov 2024 Notes: doi: 10.1016/j.ejca.2024.114336.
Chapin WJ, Hwang W, Mamtani R, O’Hara MH: Real-world uptake and effectiveness of triplet versus doublet chemotherapy with bevacizumab in patients with metastatic colorectal cancer in the United States. ESMO Gastrointestinal Oncology 5: 100087, Sep 2024.
Chapin WJ, Hwang W, Mamtani R, O’Hara MH: Low- vs High-Dose 5-FU in Triplet Chemotherapy Plus Bevacizumab for Patients With Colorectal Cancer. JAMA Netw Open 7(7): e2424855, July 2024.
Rathore S, Reiss KA, Teitelbaum UR, Chapin WJ: Exploring the association of smoking status with clinical outcomes in patients with mPDAC treated on a clinical trial of maintenance niraparib plus immune checkpoint blockade. American Society of Clinical Oncology Annual Meeting, Chicago, IL. 42(suppl 16): Abstract e16302, May 2024 Notes: "Poster Presentation"
William Joseph Chapin, Wei-Ting Hwang, Ronac Mamtani, and Mark H. O'Hara: Real-world comparison of low- versus high-dose continuous 5FU infusion in patients receiving triplet chemotherapy plus bevacizumab for newly diagnosed metastatic colorectal cancer (mCRC). Journal of Clinical Oncology 42(3_suppl): 62-62, Jan 2024.
William Joseph Chapin, Wei-Ting Hwang, Ronac Mamtani, Mark H O'Hara: Real-world comparison of triplet-versus doublet-chemotherapy with bevacizumab in patients with newly diagnosed metastatic colorectal cancer (mCRC). The American Society of Clinical Oncology Annual meeting, Chicago, IL. American Society of Clinical Oncology, 41(16_suppl): 3574-3574, Jun 2023 Notes: "Oral Presentation"