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What Mark Herzlich's Story Can Help Us Understand About Ewing Sarcoma
The football star was treated for Ewing sarcoma, returned to the field, and won a Super Bowl. Here is what that rare bone cancer means, explained calmly.
A plain-language summary based on public reporting and trusted sources, linked below.
Please note: this page is educational only — it is not medical advice, and it does not speculate about anyone’s health beyond reliable public reporting. For questions about your own health, talk with your healthcare team.
What is on the record
ESPN's own biography of Mark Herzlich sets out the sequence. He was an All-America linebacker at Boston College and the 2008 ACC Defensive Player of the Year. The following year he was diagnosed with Ewing's sarcoma, a rare bone cancer.
He had chemotherapy, radiation, and surgery, then announced live on ESPN's College GameDay that he was cancer free. He rejoined his team for the 2010 season and started all 13 games, then played seven NFL seasons with the New York Giants and won a Super Bowl.
That is what has been made public. This page does not go past it. What follows is the disease.
A cancer of adolescence
Ewing sarcoma is rare and it is young. NCI reports an incidence of 3.0 cases per million in people under 20 in the United States, and the rate climbs with age through childhood: 1.0 per million at ages 1 to 4, 2.3 at 5 to 9, 4.3 at 10 to 14, and 4.5 at 15 to 19.
It is not evenly distributed. NCI notes that a risk-linked variation in the EGR2 gene is found much more often in White people than in Black or Asian people, which may be part of why Ewing sarcoma is less common in the latter groups.
NCI notes that Ewing sarcoma arises from a bone marrow-derived mesenchymal stem cell. Most tumors carry a translocation, a swap of genetic material, joining part of the EWSR1 gene to a gene in the ETS family. Older names — peripheral primitive neuroectodermal tumor, Askin tumor, extraosseous Ewing sarcoma — all describe the same thing. Our page on Ewing sarcoma covers the biology in more depth.
Where it starts
Bone is the usual site, but not always. NCI's breakdown of primary sites puts the pelvis at 18%, soft tissue at 19%, the shin and foot bones at 14%, the rib at 11%, the thigh bone at 11%, the spine at 7%, the upper arm at 7%, and the skull at 5%.
Roughly a quarter of people already have metastatic disease when they are diagnosed, most often in lung, bone, or bone marrow.
The delay problem
NCI records something uncomfortable and useful. The interval from first symptom to diagnosis has a median of two to five months, and it runs longer in older patients and in pelvic tumors.
The reason is easy to see. A teenager with a painful, swollen leg after sport looks like an injury. The distinguishing pattern is pain that does not settle with rest, keeps going for weeks, and often wakes the person at night.
NCI adds a finding worth knowing for anyone in that gap: the time from first symptom to diagnosis has not been linked to whether the disease had spread, to surgical outcome, or to survival.
What the workup involves
NCI lists MRI of the primary site, CT of the chest, a PET scan, a bone scan, bone marrow aspiration and biopsy, x-rays, a full blood count, and blood chemistry including lactate dehydrogenase. Many centers now use PET in place of the bone scan.
The whole involved bone is imaged, not just the tumor. That is to look for skip metastases, separate deposits in the same bone, which one review found in 15.8% of patients.
What treatment involves
Every person with Ewing sarcoma gets chemotherapy, even when scans show disease in only one place. NCI's reasoning is explicit: most people with apparently localized disease have hidden metastases at diagnosis.
The US standard regimen alternates two combinations. VDC is vincristine, doxorubicin, and cyclophosphamide. IE is ifosfamide and etoposide. They are given in alternating cycles.
One trial changed the schedule rather than the drugs. In a Children's Oncology Group study of 568 people with newly diagnosed localized disease, giving the same regimen every two weeks instead of every three raised five-year event-free survival from 65% to 73%, with no increase in toxicity. At ten years, both event-free and overall survival remained higher.
Local control comes from surgery, radiation, or both. Our page on chemotherapy covers what the drug side involves.
The survival picture
NCI reports that people with localized Ewing sarcoma on current regimens reach roughly 70% event-free and overall survival at five years.
The longer view shows how much has moved. Five-year survival for Ewing sarcoma has risen from 59% to between 80% and 85% for children under 15, and from 20% to 69% for adolescents aged 15 to 19.
These are group figures from trial and registry populations. They do not describe any one person, and outcomes differ sharply between localized and metastatic disease.
When to get checked
There is no screening test for bone cancer, and NCI has no evidence-based prevention information for it. It is found because someone takes a persistent symptom seriously.
NCI lists these as reasons to see a doctor:
- A lump in the arm, leg, chest, or pelvis, which may feel soft and warm
- Pain or swelling near the lump
- Fever with no known cause
- A bone that breaks with no real injury
- A limp when walking
- Fatigue, weight loss, or anemia
- Shortness of breath
- Back pain, weakness, numbness, or paralysis in the arms or legs
The practical threshold: bone pain in a child, teenager, or young adult that has lasted more than three to four weeks, is not improving with rest, or wakes them at night deserves an x-ray rather than more physiotherapy.
What this does not mean
- One athlete's return to elite sport is his own outcome. It cannot forecast anyone else's.
- A long delay before diagnosis is common in this disease, and NCI reports it has not been linked to worse survival. That is worth knowing if it has already happened.
- Most persistent bone pain in young people is not cancer. The point is that it needs a cause found.
- The survival figures are group averages, and the gap between localized and metastatic disease is large.
Sources
- ESPN Press Room, Mark Herzlich biography — https://espnpressroom.com/us/bios/mark-herzlich/
- NCI PDQ, Ewing Sarcoma Treatment (Health Professional Version) — https://www.cancer.gov/types/bone/hp/ewing-treatment-pdq
- NCI PDQ, Ewing Sarcoma Treatment (Patient Version) — https://www.cancer.gov/types/bone/patient/ewing-treatment-pdq
How this article was prepared
An AI-assisted editorial system helped prepare this page. No named medical reviewer has reviewed it unless one is listed.
The National Cancer Information Foundation publishes Cancer Explained. This page is for learning. It is not medical advice and does not suggest a test or treatment.
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Put the story in context
Prevention, possible warning signs, screening, and diagnosis
This story relates to Bone cancer (Ewing sarcoma). The information below is general: it does not reveal anything else about a public person’s health, and not every point applies to every cancer. Personal advice depends on age, symptoms, family history, exposures, and medical history.
Prevention and risk reduction
Not every cancer can be prevented. Avoiding tobacco, protecting skin from ultraviolet radiation, limiting alcohol, staying active, and receiving recommended HPV or hepatitis B vaccination can lower the risk of certain cancers. A risk factor is not a prediction or a cause in one individual.
Symptoms and possible early signs
Possible signs vary and are often caused by conditions other than cancer. Changes worth discussing include a new lump, unexplained bleeding or weight loss, a persistent cough, lasting bowel or bladder changes, a changing skin spot, or symptoms that persist or worsen. Some early cancers cause no symptoms.
Screening and early detection
Screening looks for certain cancers before symptoms begin. Recommended tests exist only for some cancers and depend on age and risk. Screening can have benefits and harms; it is not the same as evaluating a new symptom, and there is no single routine scan or blood test that reliably screens for every cancer.
How cancer is diagnosed
Diagnosis may involve a history and exam, imaging, laboratory tests, and often a biopsy. Pathology can identify the cancer type and may test biomarkers that guide treatment. Symptoms, screening results, tumor markers, or online stories alone cannot confirm cancer.
Learn about this story’s cancer topic
A public story may encourage questions, but it should not be used to estimate your risk or choose testing. Contact a healthcare professional about a persistent or concerning change. Seek urgent care for severe or rapidly worsening symptoms.