Medicare Annual Enrollment Period: What Can You Change?
Medicare’s Annual Enrollment Period, also commonly called Medicare Open Enrollment, runs, October 15 through December 7 each year.
Medicare Advantage and Cancer: Questions to Ask Before Choosing a Plan
Last Modified: 10/06/2026 | Reviewed by Keith Armbrecht (NPN 634015)
Quick Summary
Medicare Advantage plans cover Medicare-covered cancer treatment, including qualifying chemotherapy, but plan networks, prior authorization rules and out-of-pocket costs can become especially important when someone has cancer.
A cancer diagnosis doesn’t automatically mean Medicare Advantage is the wrong choice.
It does mean you should carefully investigate access to:
oncologists
cancer centers
hospitals
specialty drugs
and
treatment authorization.
Key Facts
- Medicare covers qualifying chemotherapy.
- Medicare Advantage must cover Medicare-covered services.
- Medicare Advantage plans may have provider networks.
- Prior authorization may apply to certain services or treatments.
- Plan out-of-pocket limits matter during expensive treatment.
- Prescription formularies matter for oral cancer drugs covered by Part D.
- Cancer-center access can vary by network.
- A particular oncologist may participate in one plan but not another.
- Medicare Advantage plans can’t charge more than Original Medicare for certain services, including chemotherapy.
- Continuity-of-care protections apply to certain ongoing authorized treatment.
Question #1: Is Your Oncologist in Network?
Don’t ask only:
“Does my oncologist take Medicare?”
Ask:
“Is my oncologist in this specific Medicare Advantage plan?”
Those aren’t the same question.
Question #2: Is Your Preferred Cancer Center in Network?
If you have a preferred:
- Cancer hospital
- Academic medical center
- Specialty clinic
- Surgeon
- Radiation center
verify each one.
Question #3: What Does Chemotherapy Cost?
Original Medicare Part B covers qualifying outpatient chemotherapy.
After the Part B deductible, Original Medicare beneficiaries generally owe 20% of the Medicare-approved amount without supplemental coverage.
Medicare Advantage plans set their own cost-sharing rules within Medicare requirements.
Plans can’t charge more than Original Medicare for certain services such as chemotherapy.
Question #4: Does Prior Authorization Apply?
Medicare Advantage plans often require prior authorization for certain services.
For someone in cancer treatment, ask about authorization rules for:
- Advanced imaging
- Surgery
- Radiation therapy
- Infusion therapy
- Rehabilitation
- Other treatment
Question #5: What Is Your Maximum Out-of-Pocket?
Cancer treatment can involve significant healthcare utilization.
Your plan’s:
Maximum out-of-pocket
therefore deserves close attention.
Question #6: How Are Oral Cancer Drugs Covered?
Some cancer drugs may fall under:
Part B
while others may fall under:
Part D.
Check the plan’s drug formulary, tier and utilization requirements.
What If You’re Already Receiving Treatment?
Medicare Advantage has continuity-of-care protections.
If you’re receiving an ongoing course of treatment and change plans, applicable Medicare rules provide a transition period before the new plan can require new prior authorization for that ongoing treatment.
Video Explanation from Keith
Medicare Advantage and Cancer: What I Would Check First
Keith's Take
This is where I want someone evaluating Medicare Advantage based on healthcare—not extra benefits.
If you have cancer, I don’t care nearly as much about the gym membership.
I care about:
Your oncologist
your hospital
your cancer center
your medications
prior authorization
and
your worst-case annual cost.
Medicare Advantage can work well for some cancer patients.
But this is the time to understand every important restriction before treatment begins.
Keith Armbrecht
Medicare on Video
Frequently Asked Questions
Q. Does Medicare Advantage cover cancer treatment?
A. It must cover Medicare-covered Part A and Part B services according to Medicare requirements.
Q. Is chemotherapy covered by Medicare?
A. Yes, qualifying chemotherapy is covered.
Q. Can Medicare Advantage require prior authorization?
A. Yes, for certain services and supplies.
Q. Can a cancer center be out of network?
A. Yes.
Q. Can chemotherapy cost sharing be higher than Original Medicare?
A. Medicare says MA plans can't charge more than Original Medicare for certain services including chemotherapy.
Q. Should I check my maximum out-of-pocket?
A. Absolutely.
Q. Does Part D cover oral cancer drugs?
A. Some outpatient cancer medications may be covered under Part D; coverage depends on the drug and Medicare rules.
Q. Does having cancer guarantee I can switch to Medigap?
A. No. Medigap eligibility is a separate issue.
Official Government Sources
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