Childhood Cancer

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Childhood Cancer

Osteosarcoma

Osteosarcoma is a malignant tumor of the bone and the most common bone sarcoma. Scientific advances over the past 50 years have dramatically improved the outcome for children and adolescents diagnosed with osteosarcoma. Advances in surgical techniques have also improved their quality of life.

Who gets osteosarcoma?

In the United States, osteosarcoma is diagnosed each year in approximately 450 children, teens, and young adults. The peak incidence occurs between the ages of 10 and 24. Researchers believe there is an association between the disease and the rapid period of bone growth during adolescence.

In adolescents, osteosarcoma is the third most common cancer, following leukemia and lymphoma. The disease is slightly more common in males than in females and is slightly more common in Black and Hispanic children than in White children. Osteosarcoma is believed to be more common in individuals who will grow to be taller than average.

In children and adolescents, about half of these tumors arise in the end of the thigh bone (femur) closest to the knee or in the end of the shin bone (tibia) closest to the knee. About 10 percent of the time it appears in the end of the upper arm bone (humerus) nearest the shoulder. Less common sites are the pelvis, jaw, spine, and ribs. Twenty percent of children diagnosed with osteosarcoma have metastases (cancer that has spread to other places in the body) at the time their cancer is found. Of this group, approximately 85 percent have tumors in their lungs.

Genetic factors

The day our daughter was diagnosed with osteosarcoma, I was sick with a fever of 103° and had to stay home while her dad took her to the appointment. My husband told me it was the worst day of his life when she looked up at him and asked him if she was going to die. Both he and the doctor immediately responded that we were all going to do everything to keep that from happening. She trusted that we would take care of the cancer and she would recover.

The cause of osteosarcoma is not known, but some associations with other conditions have been identified. For example, retinoblastoma, a rare eye cancer of childhood, is associated with osteosarcoma. Children who have the inherited form of retinoblastoma have a substantial risk of developing osteosarcoma. The risk appears to be increased by treatment with radiation to the bones of the eye socket. But the increased frequency of osteosarcoma in non-irradiated sites (e.g., arms and legs) indicates a genetic abnormality predisposing the child to these two cancers. For more information, see Chapter 5, Retinoblastoma.

Other genetic syndromes that may predispose young people to developing osteosarcoma include Bloom syndrome, Werner syndrome, Li-Fraumeni syndrome, and Rothmund-Thomson syndrome.

Environmental factors

Exposure to radiation increases the risk of developing osteosarcoma—about 3 percent of children diagnosed with the disease had previous irradiation of the site. Studies have found that osteosarcoma occurs 4 to 40 years after irradiation. Children and adolescents with osteosarcoma in a former radiation field have the same cure rate as any other person with the disease, as long as they are treated with standard surgery and chemotherapy. Osteosarcoma has also been associated with bone-seeking radioisotopes, such as radium 224, which is used to treat tuberculosis.

Osteosarcoma signs and symptoms

Osteosarcoma occurs most frequently in the long bones such as the femur and humerus. Symptoms usually include pain, with or without associated swelling. The affected area also may have an increased temperature. Often, the child will limp, as about 80 percent of these tumors are located near the knee, and the joint’s range of motion may be decreased.

Some people attribute the beginning of this cancer to an injury, but trauma to the bone does not cause cancer. Sometimes the child or teen may be diagnosed with a broken bone—even when there has been no injury to the area—and that is how the cancer is discovered.

Because symptoms can come and go, and often involve pain in the legs of active young people, signs of osteosarcoma can be present for weeks or months before a diagnosis is reached.

When Leeann was diagnosed with osteosarcoma in the left femur, I remember feeling total and utter shock. She had been complaining of pain in her knee for months, but since she was physically active playing basketball, baseball, and gymnastics, I assumed it was something minor like a pulled ligament. I also told her more than once that it was just “growing pains.” Fortunately, she persisted and we took her to a local orthopedist. The orthopedist asked us to make an appointment with a pediatric orthopedist two and a half hours from home. I knew at this point it was something much more serious than a pulled muscle. Once the initial diagnosis was made, we went into a fog.

At diagnosis, about 20 percent of young people with osteosarcoma have x-ray evidence of disease that has spread to other parts of the body (called metastatic disease). When metastatic disease is in the lungs, there are usually no symptoms, although it occasionally causes shortness of breath, chest pain, and coughing. Children with advanced metastatic disease may have fever and weight loss.

Diagnosis of osteosarcoma

Specific tests and procedures are performed before a diagnosis of osteosarcoma can be reached. Any child or teen with suspected osteosarcoma should be seen by a pediatric oncologist and an orthopedic oncologist (a surgeon) who have experience treating this disease. The oncologist obtains the child or teen’s medical history and performs a complete physical examination. A complete blood count (CBC) and differential are ordered (see Appendix A, Blood Tests and What They Mean), along with other bloodwork and a urinalysis.

The first imaging studies done are often x-rays of the area suspected of having a malignancy. Because these tumors have a distinct appearance when viewed on plain x-ray films, a radiologist may suspect osteosarcoma is present based on the x-ray alone. A magnetic resonance imaging test (MRI) of the affected region is usually done, and a computerized tomography (CT) scan and a bone scan may also be performed. To read about these imaging tests, see Chapter 10, Coping with Procedures.

A definitive diagnosis of osteosarcoma can only be made by examining part of the tumor under a microscope. A complete evaluation by the orthopedic or pediatric oncologist, including imaging studies, should be done before the initial biopsy, because a poorly performed biopsy may jeopardize the option of future limb-sparing surgery. An experienced surgeon or an interventional radiologist (a doctor who specializes in diagnosing and treating diseases using medical imaging and minimally invasive treatments) who has extensive experience with the treatment of pediatric sarcomas should perform an open biopsy (when a surgical incision is made through the skin to expose and remove tissues) or a needle biopsy (a thin needle is used to take tissue or fluid samples from muscles, bones, or organs). The samples of the mass that are removed will be examined by a pathologist.

Staging

I was a 16-year-old cheerleader preparing for a national competition when my knee started to hurt. I thought it was just a sports injury, and I put ice on it. When it didn’t improve, I went to physical therapy and then to a specialist in sports medicine. He took an x-ray and then sent me for an MRI. That night he called to say, “I’m so sorry, but you have a tumor.” I had a biopsy the next day. It was osteosarcoma.

Once osteosarcoma has been diagnosed, the pediatric oncologist will perform more tests to determine whether the cancer has spread to other parts of the body.

My daughter Shoshana is now 19. She was diagnosed with osteosarcoma just before her sixteenth birthday. The tumor was located in her right fibula. She also had lung metastases. Pain was her basic symptom, especially at night. We started out at the pediatrician, then an orthopedic doctor, and finally an orthopedic oncologist who did a biopsy. We were then passed on to a pediatric oncologist, who is our primary doctor. The latter two are a great team!

A CT scan or MRI of the bones, a CT scan of the chest, and a nuclear bone scan can be performed to check for metastases at sites distant from the main tumor. A bone scan that uses a radiopharmaceutical, called technetium-99m, is frequently ordered to provide the physician with clear images of the entire skeleton. These bone scans are helpful in detecting the presence of metastatic disease and “skip lesions.” Skip lesions are areas of disease occurring at different sites, but within the same bone as the primary tumor. Bone scans are sensitive to many other normal events, such as minor strains and injuries to the bone, so an abnormality on the bone scan does not always mean the tumor has spread.

There are two stages of osteosarcoma:

•  Localized. A localized tumor is limited to the bone of origin.

•  Metastatic. Tumors are found in other parts of the body, particularly the lungs or other bones. Other sites of metastatic disease are rare but can occur.

Prognosis

Since the 1970s, the treatment of osteosarcoma has dramatically improved. The majority of children and adolescents now survive the disease, most (90–95%) with limbs still intact. The prognosis and best treatment for each child with osteosarcoma are determined by analysis of several clinical and biological features.

The most significant factors used to determine prognosis for the child with osteosarcoma are the extent of the disease at diagnosis and whether or not it has metastasized.

For children or adolescents with localized disease, important factors are the tumor’s resectability (ability of the surgeon to remove the tumor, which is determined by its size and location) and how it responds to chemotherapy.

For children or adolescents with metastatic disease at diagnosis, prognosis depends on the site of the metastases and the resectability of the metastatic tumors (either at diagnosis or after chemotherapy).

Treatment of osteosarcoma

At diagnosis, many parents do not know how to find experienced doctors and the best treatments for their child. State-of-the-art care is available from physicians who participate in the Children’s Oncology Group (COG). This study group includes pediatric surgeons and oncologists, neurologists, radiation oncologists, researchers, and nurses. COG conducts studies to discover better therapies and supportive care for children with cancer. You can learn more about COG and find a list of its member treatment centers at www.childrensoncologygroup.org.

The orthopedic and pediatric oncologists will explain to the family the best options for treatment (standard treatment or a clinical trial, if open). For more information, see Chapter 9, Choosing a Treatment. For children and teens with osteosarcoma, treatment typically consists of chemotherapy, followed by surgery, and then more chemotherapy. Osteosarcoma is not very responsive to radiation, so it is rarely used.

Surgery

Improvements in the surgical management of osteosarcoma over the past few decades have significantly improved long-term survival rates and the quality of life for children diagnosed with this disease.

Surgery usually occurs after a period of preoperative chemotherapy, although some treatment plans require surgery before chemotherapy. Successful surgical removal of the primary tumor most often consists of limb-salvage surgery or, in less than 10 percent of cases, amputation. A surgical procedure called a thoracotomy (opening the chest cavity) is used to biopsy or remove tumors in the lungs.

Eric was diagnosed at age 15 with osteosarcoma in his left femur. He had chemotherapy and successful limb salvage surgery. Before cancer he was a baseball player, aggressive in-line skater, and a real on-the-go kid. I’m proud to say, he took his new limitations very well. He was able to remain very active despite his reconstructed leg. Although high-impact activities were discouraged, he continued to ride his bicycle and go canoeing, hiking, and camping in the mountains. He played softball with his friends, but preferred to let someone else do his base running.

The doctors, the young person with osteosarcoma, and the parents need to have thorough and honest discussions about surgical options. There are pros and cons to both amputation and limb salvage procedures. For instance, lower leg amputations allow survivors to continue playing sports, whereas limb salvage procedures generally do not. Youngsters who are still growing when limb salvage surgery is done will have marked leg length discrepancies as they age, sometimes requiring multiple surgeries, although this has improved with the development of expandable prostheses. Limb salvage, however, can sometimes provide a good cosmetic result. There are many, many factors to consider. Given the same information, different families may make different decisions.

The treatment team will discuss several factors that affect treatment options, including the size, location, and extent of the primary tumor; the presence or absence of distant metastases; the age of the child; skeletal development; presence of fractures in the bone; and patient and family preferences. Remember, only surgeons who have a great deal of experience treating osteosarcoma should operate on your child. If you do not feel your child’s surgeon has enough experience, it is your right to request another surgeon or to find another treatment center that has a surgeon who has considerable experience with osteosarcoma.

Amputation

Shoshana had limb-sparing surgery after weeks of chemotherapy (all high-dose through her central line). The surgery took 9 hours. She got back onto her chemotherapy protocol a few weeks later. We did the wheelchair, then crutches (for a long time), then a cane, then walking, dancing, running! She had surgery to remove the lung tumors later that same year.

Amputation involves removal of all or a portion of an arm or a leg. Two forms of surgery have been developed in recent decades to improve the mobility of children who require an amputation of a portion of the leg. Both methods still require the use of a prosthetic device, but they better preserve the leg’s functionality. One form of this is a tibia turnup, where the leg is amputated above the knee and the tibia bone from the lower leg is turned upside down; this makes it possible for the lower end of the tibia to be fused to the bottom of the femur.

The other surgery used to improve function in children who require a leg amputation above the knee is called rotationplasty. The length of the lower portion of the leg is adjusted, then rotated 180 degrees, and attached to the femur. The ankle joint serves as a replacement for the surgically removed knee joint. An artificial limb is then designed to fit over the ankle. Rotationplasty surgery can cause cosmetic and psychosocial difficulties because of the appearance of the reconstructed limb, but it can be a good choice to help promote maximum function for an active young person.

Children or teens who have a limb amputated need a great deal of rehabilitation and psychological support. Although amputation is traumatic at any age, osteosarcoma typically occurs during the teenage years, when appearance is especially important to an adolescent’s emotional well-being. State-of-the-art prosthetic limbs allow great mobility, as well as cosmetic appeal. Studies have demonstrated similar quality of life between osteosarcoma survivors who had amputation and those who had limb-salvage surgery.

Limb-salvage surgery

Advances made in limb-salvage procedures have enabled this technique to be used with an increasing number of children and teens. The challenge for the surgeon is to remove all evidence of disease while maintaining surrounding nerves and blood vessels. The structural integrity of the bone is then restored through the use of bone grafts or metallic devices. The survival rate for children or teens who have limb salvage surgery is equivalent to that of amputation.

The potential benefits of limb-salvage procedures are both functional and psychological, although this has been difficult to prove. However, limb-sparing surgery is not used if there is any doubt about whether the surgeon will be able to completely remove the tumor. The first priority is to remove the entire tumor.

Vince has played baseball since he was 18 months old and his great grandmother would patiently spend hours pitching a foam ball to him. By age 8, he was on a travel baseball team that was amazing. He was diagnosed with osteosarcoma in his left distal femur at age 11. He had limb salvage surgery and his orthopedic surgeon told him no running, no jumping, no contact sports, certainly no baseball. He suggested he switch to swimming or golf. We as parents knew baseball had to remain a factor for his own mental health. So we fought against the surgeon and said just tell us what the limitations of his parts are, and what are the consequences of broken pieces. From that, we as a family came up with what could and could not be done on the baseball field (and what we did was against the doctor’s advice).

As parents, we tried to protect our son, so when he went back on the field (even during treatment) we made him wear extra padding to protect his port, and we all knew he was more of an inspirational player than a force to be reckoned with. But every milestone he made encouraged him to set the next one. First, he wanted to get back in uniform and sit on the bench. Then, he wanted to play toss before the game. Then he wanted an at bat. Then he wanted to play in the field. The bottom line is cancer does indeed take things away: it steals your ability to run fast enough, it costs you time that should have been spent improving skills, it might affect self-esteem when you aren’t as good as you “might have been.”

But Vince is now almost 18, and has worked himself into playing at a high school level. He played 2 years of JV and now this will be his second year on varsity. I find that I still have those bitter thoughts, why didn’t he get the chance to reach his full potential. When some of his friends have been having their official signing days with colleges (and baseball scholarships) I had my weepy times. But I also think this is more of a problem for us parents than for the kids. The thing right now is that while he is considering which college to attend, he has several other options that do not include baseball. At some point, he may walk away from baseball teams to be at a bigger school or a different location or in a program that he likes. We will always think we made the right choice to allow Vince to go as far as he could.

Children or teens who have a broken bone at the time of diagnosis may not be good candidates for limb-salvage surgery. Chemotherapy before surgery may cause poor healing of the fracture, which creates added obstacles when attempting limb-sparing techniques. The fracture also creates the risk that the tumor will spread locally. Tumor location, as well as the age of the child, also affect the likely success of limb-salvage surgery, and in some cases amputation may be a more suitable approach.

Leeann’s limb-salvage surgery kept her leg in an immobilizer for 6 weeks, day and night. There was a big problem getting her flexibility back, even with a year of painful physical therapy. The pain was manageable with the help of morphine, but getting her around was very difficult. Even the 3-hour car ride home was a trial. Once at home, we rented a wheelchair for the first month until she felt comfortable on crutches. I spent many hours on the floor of the bathroom, holding her leg up while she used the toilet. She became a real pro on those crutches!

Several different bone replacements are available for use in limb-salvage surgery:

•  Autologous grafts involve removing a healthy bone from another area of the child’s body to replace the diseased bone. Sometimes the blood vessels that feed the bone can be moved along with it to keep the bone alive in its new location. Allografts use bone from cadaver donors and are preferred when more bone is needed than can be removed from another part of the child’s body.

•  An endoprosthesis, usually made of steel or titanium, is a manufactured replacement for the diseased bone.

My daughter was 16 when she was diagnosed with osteosarcoma. During her surgery, they wrapped a muscle from the back of her calf around to the front to hold the bone graft in place. It left a large open area that was covered by a skin graft from her thigh. It certainly worked in holding her graft in place, but left her leg looking pretty awful (even though we had a plastic surgeon assist with that part of the surgery), and I haven’t seen a scar like it on anyone else. They also put small bone slivers from other bones around the graft sites in hopes of faster grafting, and that apparently worked as well. She walks much better than they expected—a slight limp but no braces necessary. She never did regain feeling in the bottom of her right foot. Sometimes she thinks amputation would have been better, because with a prosthesis she’d be able to run and jump and roller blade and participate in sports, things she can’t do now with the bone graft and complete knee replacement.

Possible problems with limb replacement are infection, graft failure, and longevity of the manufactured bone replacement.

Lung surgery

Tyler was diagnosed with osteosarcoma of his left femur when he was 7. Half of his femur had to be removed. When Tyler was 8 years old, we approached a surgery decision. We had three options: One option was a rod in place of half his femur and knee, which really wasn’t an option

because the rod couldn’t be lengthened to meet the needs of a growing child. The other two options were rotationplasty and amputation. Tyler had one last MRI of his leg to see how the tumor had responded to chemotherapy. Imagine our surprise when the surgeon said to us, “I’m going to make your decision a little harder.” The tumor had shrunk enough so his growth plate could be saved. With this good news came another surgery option, a donor bone. We left feeling good and had some research to do. We talked with several osteosarcoma patients who had gone through all the options we were faced with, and we also spoke with other surgeons. After long consideration and praying about our new option, we decided the best surgery for Tyler would be a vascularized fibular allograft. Tyler’s fibula was inserted down the center of the cadaver bone to give him blood flow and added strength. The surgery took about 16 hours because attaching all the blood vessels was a long process. He stayed in the ICU for 3 days with a fever and low oxygen levels. Once everything was under control, they moved him to the orthopedics floor for a week.

Tumors located in the lungs can often be removed during a procedure called thoracotomy (surgery in which an incision is made to open the chest cavity). Disease located within the ribs sometimes requires the removal of affected bones and replacement with a synthetic material to reconstruct the chest wall.

Chemotherapy

Chemotherapy has greatly improved the long-term survival of children with osteosarcoma. Before the use of chemotherapy, the prognosis was very poor for a young person diagnosed with osteosarcoma, despite amputation. This is because almost all children, including those with no obvious signs of metastatic disease, have microscopic disease in the lungs at the time of diagnosis.

Current protocols for osteosarcoma usually use doxorubicin and two or three other chemotherapy drugs from this list: high-dose methotrexate, cisplatin, ifosfamide, or etoposide (also called VP-16).

After chemo, Tyler was feeling sick but ice cream really seemed to help. For a while he was getting so sick and losing weight because he couldn’t keep any food down, so they put him on medicine that encouraged him to eat and then he ate like crazy. When Tyler started getting mouth sores from chemo, we reached out to our support group to see if anyone had some suggestions. One of the moms suggested that we use aloe vera juice. When her son was going through treatment, a nurse recommended it. Tyler would swish it around and swallow it three times a day. It helped relieve a lot of pain with existing mouth sores and prevented them from appearing. As long as we started him on aloe before treatment and continued it throughout, he wouldn’t get mouth sores.

Chemotherapy is generally given before and after surgery. Giving chemotherapy before surgery may facilitate limb-salvage procedures by shrinking tumors before they are removed. Children who respond well to pre-surgical chemotherapy (more than 90 percent tumor death) have a better prognosis than those who do not respond as well to initial chemotherapy.

Overall, Leeann survived chemotherapy without too many side effects. The usual nausea was controlled with Zofran® and Benadryl®. The hardest part was losing her hair. She was at such a critical time in her growing up that showing up at a new school wearing a wig caused a lot of anxiety.

For information about current clinical trials and the newest treatments, see the section at the end of this chapter called “Information on standard treatments.”

The skeletal systemEwing sarcoma family of tumors

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