Samuel Klempner, MD
Enriched profileAssociate Professor, Massachusetts General Hospital and Harvard Medical School; Medical Oncologist, Mass General Brigham Cancer Institute, Tucker Gosnell Center for Gastrointestinal Cancer · Massachusetts General Hospital
Samuel Klempner is Associate Professor, Massachusetts General Hospital and Harvard Medical School; Medical Oncologist, Mass General Brigham Cancer Institute, Tucker Gosnell Center for Gastrointestinal Cancer at Massachusetts General Hospital. OpenAlex indexes 888 publications with 12,737 citations (h-index 53); ClinicalTrials.gov lists 2 registered studies with this person as an investigator.
Data verified 17 Oct 2026
Overview
Updated 18 Oct 2026
Samuel Klempner, M.D, is Associate Professor, Massachusetts General Hospital and Harvard Medical School. The public record shows 888 publications with 12,737 citations (h-index 53), centered on Gastric Cancer Management and Outcomes, Cancer Immunotherapy and Biomarkers, Cancer Genomics and Diagnostics. It also documents an investigator role on 2 registered clinical trials, industry payments reported by 26 companies.
- Most recent indexed publication: 2026 · Science immunology
- Top research focus: Gastric Cancer Management and Outcomes
- 2 registered trials on ClinicalTrials.gov
- Open Payments reporting from 26 companies
Generated from the cited public record · current as of 18 Oct 2026. Every fact links its source below.
Indications focus
from trials led + research topicsResearch focus
OpenAlex concept fingerprintDrugs & molecules
across trials, industry payments and publicationsWorks with
trial sponsors and companies reporting paymentsScholarship
indexed output and impact (OpenAlex)Distinct works indexed by OpenAlex, matched via ORCID; 71 in PubMed.
Total citations across indexed works.
Hirsch index (OpenAlex). i10-index 153.
Clinical & industry
trials, payments and federal fundingFederally funded research awards.
Contact
The practice address and phone this provider lists in the federal NPPES (CMS) registry.
Practice address
Telephone
Practice address and telephone from the federal NPPES registry.
Sign in to view contact details →Clinical trials
Updated 18 Oct 2026
Listed as an investigator on 2 registered studies on ClinicalTrials.gov. The most recent:
- Zimberelimab + Domvanalimab in Gastroesophageal Adenocarcinoma
Sponsor: Massachusetts General Hospital
- Ivonescimab in Comb. With FOLFOX in Advanced HER2 Neg. GEA
Sponsor: Massachusetts General Hospital
Industry payments
Updated 18 Oct 2026
26 companies reported payments to CMS in program years 2021–2025. These are public disclosures, not judgments. The latest:
- AstraZeneca UK LimitedProgram year20256 payments$13,198openpaymentsdata.cms.gov ↗
- AstraZeneca Pharmaceuticals LPProgram year20257 payments$10,930openpaymentsdata.cms.gov ↗
- Astellas Pharma Europe LtdProgram year20255 payments
Medicare prescribing footprint (2024)
The drugs this prescriber writes for Medicare patients, grouped by drug class and therapeutic area. Every percentage is a share of their total prescribing, so you can see what they prescribe most. These are proportions, not patient counts or dollar amounts. No condition is inferred: the claims record what was prescribed, never why.
Metabolism & gastrointestinal
46.5%Proton pump inhibitor20.2%Omeprazole100%Part D≥11 patientsCorticosteroid15.2%Prednisone100%Part D<11 patients+ 1 more class in this area
Nervous system
24.2%Opioid Agonist12.1%Oxycodone Hcl100%Part D<11 patientsPhenothiazine12.1%Prochlorperazine Maleate100%Part D≥11 patientsBlood & clotting
16.2%Factor Xa inhibitor16.2%Eliquis100%Part D<11 patients
Drug classes come from the WHO ATC and U.S. National Library of Medicine (RxClass) classifications; prescribing counts come from the CMS Medicare Part D Prescribers file. Each drug is counted once, under its primary class. Medicare fee-for-service only, so no Medicare Advantage, commercial, or pediatric prescribing is included. CMS publishes this data about 17 months after the fact.
NIH funding
We didn't find any NIH-funded research awards for this person in NIH RePORTER. Why? →
Congress activity
Updated 18 Oct 2026
114 congress contributions (2012–2026) across AACR, ASCO, ASTRO, ESMO per OpenAlex. The most recent:
- Abstract 6134: Immunomodulatory PIGR + RORC + dendritic cells (PRDCs) are enriched in malignant ascites
AACR Annual Meeting
AACR2026Co-author - Abstract CT223: AACR Adaptive Biomarker-Driven Organ Preservation Trial in GE Adenocarcinomas (AACR-ADOPT-GEA)
AACR Annual Meeting
AACR2026Co-author - AMIGO: A phase 2 trial of amivantamab in EGFR or MET- amplified gastroesophageal adenocarcinoma (GEA).
ASCO Annual Meeting
ASCO2026Co-author
Published abstracts are attributed via the same ORCID-disambiguated authorship as publications, so each is DOI-verified. Podium roles (invited talks, session chairs) and oral/poster type are added as program data is confirmed.
Publications
Updated 18 Oct 2026
Their five most recent publications, matched to their ORCID record and linked to PubMed.
- Multiomic analysis of malignant ascites defines RORC-expressing dendritic cells at sites of metastasis.
Science immunology
Article2026 - A Phase II Study of Nivolumab and Ipilimumab with Radiation Therapy in Patients with Metastatic, Microsatellite Stable Colorectal Cancer.
Clinical cancer research
Article2026 - Author Correction: Evolution of claudin18.2 therapies in gastroesophageal cancers.
Nature medicine
Erratum2026 - Spatial organisation of tumor-infiltrating B-cells informs immune checkpoint inhibitor response in Claudin 18.2-expressing gastric cancer.
Clinical cancer research
Article2026
Most-cited works
by citation count (OpenAlex)- 01Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in OncologyArticle1,687 citations2022
- 02
- 03
- 04
- 05Adagrasib with or without Cetuximab in Colorectal Cancer with Mutated KRAS G12CArticle517 citations2022
Network
Updated 18 Oct 2026
The people this person publishes with most, by number of co-authored papers. Names link to their own profile when we have one.
Online presence
Updated 18 Oct 2026
This person's own public accounts first, then places where others mention them. Two different things, listed separately.
Owned accounts
public accounts run by this person- Doximity
doximity.com/pub/samuel-klempner-md
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →doximity.com ↗
Mentions by others
where others cite or feature them- Other
massgeneralbrigham.org/en/doctors/k/samuel-klempner-3008144
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗
We list an account only when the public record ties it to this person. verified means we've confirmed the match in more than one place; provisional means it looks right but we're still confirming.
Background & recognition
Updated 18 Oct 2026
Credentials, appointments and honors, newest first, each linked to the public source it came from.
Education
degrees and training on record- provisionalFound in a cited public source but not yet independently corroborated. Published as a labeled candidate and queued for verification.How we verify →massgeneralbrigham.org ↗
Editorial & leadership roles
journal and society appointments- Member
American Society of Clinical Oncology (ASCO)
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗ - Member
European Society of Medical Oncology (ESMO)
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗ - Member
American Association for Cancer Research (AACR)
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗ - Committee Member
NRG Non-Colorectal Committee
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →esmo.org ↗ - Co-Chair
NCI Esophagogastric Task Force
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →esmo.org ↗ - Member
NCCN Guideline Committees for Gastric and Esophageal Cancers
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →esmo.org ↗ - Editorial Board Member
JCO Precision Oncology
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗ - Advisory Board Member
Debbie's Dream Foundation
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗ - Advisory Board Member
Hope for Stomach Cancer
verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →massgeneralbrigham.org ↗
Awards & honors
honors on the public record- verifiedCorroborated by findmyKOL. We matched this record across two or more independent public sources (or a verified ORCID / NPI identifier bridge) before attributing it to this person.How we verify →esmo.org ↗
Every item links to where we found it. verified means we've confirmed it in more than one place; provisional means we found it and are still confirming.
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