What Is Multiple Myeloma?
A plain-language overview of multiple myeloma and other plasma cell neoplasms, based on National Cancer Institute resources.
Source: National Cancer Institute · Verified 2026-07-02
The 30-second version
Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors in bone or soft tissue. When there is only one tumor, it is called a plasmacytoma. When there are multiple tumors, it is called multiple myeloma.
Key takeaways
- Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors.
- These tumors can form in bone or soft tissue.
- When there is only one tumor, the disease is called a plasmacytoma.
- When there are multiple tumors, it is called multiple myeloma.
- Multiple myeloma is one type of plasma cell neoplasm.
- NCI notes it does not have evidence-based information on preventing or screening for plasma cell neoplasms.
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The full explanation.
The simple version
Multiple myeloma is a type of plasma cell neoplasm. Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors. These tumors can form in bone or in soft tissue.
In short: multiple myeloma is a plasma cell neoplasm, a cancer that starts from abnormal plasma cells.
One tumor or many
Plasma cell neoplasms are grouped by how many tumors are present:
- When there is only one tumor, the disease is called a plasmacytoma.
- When there are multiple tumors, it is called multiple myeloma.
Both are types of plasma cell neoplasms. The main difference described here is the number of tumors.
In short: a single tumor is a plasmacytoma, while multiple tumors are multiple myeloma.
Prevention and screening
The National Cancer Institute notes that it does not have evidence-based information about preventing plasma cell neoplasms, including multiple myeloma. It also notes that it does not have evidence-based information about screening for these conditions.
Everyone's situation is different. Your healthcare team is the best source of information about a specific diagnosis and any next steps.
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What Is Multiple Myeloma: the quick overview
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Coming soonWhat Is Multiple Myeloma, explained simply
The core ideas with friendly animation and plain language.
Coming soonUnderstanding what is multiple myeloma — full lesson
A deeper walkthrough covering the key takeaways and common questions.
Coming soonVideo transcript▾
A full, readable transcript will appear here when the video is published — so the lesson is accessible whether you prefer to watch, listen, or read. For now, the article above is the complete text version.
Suggested animation storyboard▾
- 1Open on a calm title card: "What Is Multiple Myeloma?" with the Cancer Explained mark.
- 2Narrator reads the 30-second summary while a soft animated diagram builds on screen: "Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors in bone or soft tissue. When there is only one tumor, it is called a plasmacytoma. When there are multiple tumors, it is called multiple myeloma."
- 3Scene 2: illustrate the idea — "Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors."
- 4Scene 3: illustrate the idea — "These tumors can form in bone or soft tissue."
- 5Scene 4: illustrate the idea — "When there is only one tumor, the disease is called a plasmacytoma."
- 6Close on a reminder card: this is educational only; talk with your healthcare team, and a link to the NCI source.
Words to know
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Quick knowledge check
According to this article, what happens in a plasma cell neoplasm?
Frequently asked questions
▸What are plasma cell neoplasms?
Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors in bone or soft tissue. Multiple myeloma is one type of plasma cell neoplasm.
▸What is the difference between a plasmacytoma and multiple myeloma?
The difference is the number of tumors. When there is only one tumor, the disease is called a plasmacytoma. When there are multiple tumors, it is called multiple myeloma. Both are types of plasma cell neoplasms.
▸Where do plasma cell tumors form?
Plasma cell neoplasms form when abnormal plasma cells create cancerous tumors in bone or in soft tissue.
▸Is multiple myeloma a plasma cell neoplasm?
Yes. Multiple myeloma is a type of plasma cell neoplasm. Plasma cell neoplasms are grouped together because they all involve abnormal plasma cells forming cancerous tumors. Multiple myeloma is the form with multiple tumors.
▸Is there a standard way to screen for or prevent multiple myeloma?
According to the National Cancer Institute, it does not have evidence-based information about preventing plasma cell neoplasms, including multiple myeloma, and it does not have evidence-based information about screening for them. Your healthcare team is the best source of information for your own situation.
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Questions to ask your healthcare team
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- Is this a single plasmacytoma or multiple myeloma?
- What tests do I need to learn more about this condition?
- What does my diagnosis mean in plain language?
- What symptoms should I watch for and report?
- Where can I find reliable information and support?
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