Largest Oncology Physician Groups in the US: 2026 List for Healthcare Marketers

Last updated on August 5th, 2026

Quick Answer: What Are the Largest Oncology Physician Groups in the US?

The Oncology physician groups in the US market includes thousands of physician practices, community oncology groups, hospital-affiliated cancer programs, academic cancer centers, and multi-state oncology networks. For healthcare marketers, the most valuable targets are often not individual oncologists alone but the organizations, physician groups, practice networks, and decision-making teams that influence technology adoption, clinical services, diagnostics, pharmaceuticals, medical devices, staffing, and healthcare partnerships.

Among the largest and most recognizable oncology organizations and networks are The US Oncology Network, Texas Oncology, Florida Cancer Specialists & Research Institute, New York Cancer & Blood Specialists, Tennessee Oncology, Rocky Mountain Cancer Centers, Arizona Oncology, Illinois Cancer Specialists, and other regional oncology practices.

However, “largest” can mean different things. A group may be considered large based on its number of oncologists, practice locations, geographic footprint, patient volume, affiliations, or influence within community oncology.

This guide provides a healthcare-marketer-focused view of the US oncology physician group landscape, including major organizations, market structure, buyer roles, targeting strategies, and the data points marketers should consider when building an oncology prospecting strategy.

2026 Market Snapshot: Ampliz currently tracks 3,500+ list of oncology physician groups in the US. The actual market is broader when hospital-owned oncology departments, academic cancer centers, multispecialty groups, and independent oncology practices are included.

What Is an Oncology Physician Group?

An oncology physician group is a healthcare organization in which physicians specializing in cancer diagnosis, treatment, and management practice together under a shared organizational structure.

These organizations may include:

• Medical oncologists
• Hematologists
• Hematology-oncologists
• Surgical oncologists
• Radiation oncologists
• Gynecologic oncologists
• Pediatric oncologists
• Advanced practice providers
• Oncology pharmacists
• Genetic counselors
• Clinical research teams

The structure of an oncology organization can vary significantly.

Some practices are independent community oncology groups. Others operate as part of a national oncology network, health system, academic medical center, or hospital system.

For healthcare marketers, this distinction is important.

The physician who treats a patient may not be the same person who makes decisions about:

• Diagnostic technology
• EHR and healthcare IT
• Infusion equipment
• Laboratory services
• Genomic testing
• Clinical trial partnerships
• Specialty pharmacy
• Medical devices
• Practice management
• Revenue cycle services
• Staffing
• Patient engagement technology

Therefore, an effective oncology marketing strategy requires more than a list of oncologists.

It requires an understanding of the organization, its locations, specialties, affiliations, technology environment, and decision-making structure.

How Many Oncology Physician Groups Are in the US?

There are 3,500+ oncology physician groups in the US tracked in the Ampliz healthcare data ecosystem.

The broader oncology provider market includes several types of organizations:

The number of organizations can change over time because of:

• Mergers and acquisitions
• New practice formation
• Health system affiliations
• Network expansion
• Physician group consolidation
• Practice closures
• Changes in ownership

For marketers building account lists, this means a static directory may become outdated quickly.

A more useful oncology prospecting dataset should ideally identify current organizations, locations, physicians, executives, affiliations, specialties, and organizational relationships.

List of Largest Oncology Physician Groups and Networks in the US

The following organizations represent some of the most recognizable large oncology physician groups and networks in the United States.

Important methodology note: Ranking oncology groups purely by “number of oncologists” can be misleading because organizations report physician counts differently. Some count affiliated physicians, while others report employed physicians, participating practices, or network members.

Data source: Ampliz healthcare intelligence data. Accessed in August 2026. Access Now.

Community Oncology vs. Academic Cancer Centers

One of the most important decisions for healthcare marketers is determining whether they should target community oncology practices, academic cancer centers, or both.

If your product is designed for community oncology, targeting a large academic cancer center may produce lower conversion rates than focusing on regional physician groups.

Conversely, companies selling enterprise technology may need to prioritize health systems and academic institutions.

The lesson:

Your ideal customer profile should determine your oncology target list not the other way around.

Why Oncology Physician Groups Are a Prime Marketing Target

1. High Prescribing Authority

Oncologists often control formularies for cancer drugs, biosimilars, and specialty therapies making them decision-makers worth targeting.

2. Specialized Equipment Needs

From infusion pumps to imaging, oncology groups purchase high-cost diagnostic and therapeutic equipment regularly.

3. Central to Patient Navigation

These groups guide patients through all aspects of cancer care making them central touchpoints for products related to care coordination, EMRs, and diagnostic testing.

4. Influence on Guidelines and Research

Many oncology groups participate in or lead clinical trials, giving them influence in shaping future treatment protocols.

5. Long-Term Patient Relationships

Oncology patients typically require ongoing care over months or years. That translates into longer-term relationships between physician groups and the products they use or recommend.

Conclusion: How to Engage Top Oncology Physician Groups with Precision

Finding an oncology physician is relatively easy.

Finding the right oncology organization, the right location, and the right decision-maker at the right time is much harder.

Healthcare companies targeting oncology need more than a basic physician directory.

They need an intelligence layer that connects:

Physicians → Organizations → Locations → Affiliations → Decision-Makers → Market Segments

With Ampliz Healthcare Intelligence, healthcare marketers can build more targeted oncology audiences for prospecting, account-based marketing, market research, and sales planning.

Instead of asking:

“How do I find oncology physicians?”

Ask:

“Which oncology organizations are the best fit for my product, who makes the buying decision, and how can I reach them?”

That shift from contact lists to account intelligence can make oncology marketing more precise, scalable, and relevant.

Ready to build a targeted oncology audience? Explore Ampliz healthcare intelligence to identify oncology physician groups, healthcare organizations, and decision-makers aligned with your ideal customer profile.

FAQs

What are oncology physician groups?

Oncology physician groups are healthcare organizations where oncologists, hematologists, and other cancer specialists work together to diagnose, treat, and manage cancer patients. These groups may operate independently, as community oncology practices, or as part of hospital systems and cancer networks.

How many oncology physician groups are there in the US?

Ampliz tracks more than 3,500+ oncology physician groups in the United States. The market includes independent oncology practices, community cancer centers, multispecialty physician groups, hospital-owned oncology clinics, and academic cancer centers.

What are the largest oncology physician groups in the US?

Some of the largest oncology physician groups include The US Oncology Network, Texas Oncology, Florida Cancer Specialists & Research Institute, New York Cancer & Blood Specialists, Tennessee Oncology, Rocky Mountain Cancer Centers, and Arizona Oncology.

What information is included in an oncology physician groups database?

A comprehensive oncology physician groups database may include organization names, physician specialties, business email addresses, phone numbers, practice locations, NPIs, executive contacts, hospital affiliations, and organization details for healthcare marketing and sales.

What is the difference between an oncology physician group and a cancer center?

An oncology physician group is a physician-led practice focused on cancer treatment, while a cancer center is a broader healthcare facility that may include oncology clinics, surgery, radiation therapy, diagnostics, research, and clinical trial programs.

Subbu

V. Subramanyam
Head of Product at Ampliz | Healthcare Data & GTM Intelligence Expert

V. Subramanyam is the Head of Product at Ampliz, where he leads the strategy and development of healthcare data intelligence solutions that help sales, marketing, recruiting, and commercial teams identify and engage healthcare decision-makers across the United States.

With extensive experience in product management, healthcare data, B2B SaaS, GTM strategy, and sales intelligence, he focuses on building products that simplify healthcare prospecting through accurate physician, hospital, executive, and healthcare organization data. His work emphasizes data quality, enrichment, and AI-powered workflows that enable organizations to make faster, data-driven decisions.

Connect with Him:

• LinkedIn: https://www.linkedin.com/in/vsubramanyam
• Company: https://www.ampliz.com