Tarheel Health Portal/Chondrosarcoma

Chondrosarcomas are a rare form of cancer that are estimated to occur in 1 in 200,000 people each year. They are a malignant form of cartilage tumors. Chondrosarcomas are also relatively resistant to chemotherapy and to radiation, often making them difficult to treat. This apparent resistance to more traditional cancer treatments means that surgery is often the only way left to treat these tumors. However, preliminary studies have found some success with proton therapy radiation and with chemically induced apoptosis. Studies have recently determined that proton therapy radiation in conjunction with surgery is the “treatment of choice” for “skull-base… chondrosarcomas”. Additionally, new therapies have been discovered which may be able to increase chondrocyte apoptosis, increasing the effectiveness of traditional therapies.

Due to its rarity, chondrosarcoma is classified as a rare disease. This means that it affects less than 200,000 Americans. This rarity presents a unique problem to chondrosarcoma patients, as they lack the support that[atients with other more common illnesses have.

Chapel Hill's campus is large and diverse, and the school should be expected to offer the unique kinds of support that those who suffer from rare diseases and those who have family members with rare diseases require.

Current Treatment Options
Currently chondrosarcomas are being treated primarily with surgery, and that is viewed as the best option for treatment, being included as the main component in nearly every form of treatment. Even though new forms of radiation have seen some positive results in practice as, they are all done in conjunction with surgical resection of the tumor and surrounding tissue.

Proton Radiation Therapy
Despite the fact that surgery is still the mainstay treatment option for chondrosarcomas, new types of radiation therapy have seen some success in recent years. Radiation therapies act by disrupting cell division; however, since chondrosarcomas are usually slow-growing with minimal cell division, they are often considered to be fairly resistant to radiation therapy. While traditional radiation is fairly ineffective in treating chondrosarcomas, proton therapy has shown some positive results due to its ability to be targeted in small beams and because it has minimal release of energy into surrounding tissue, allowing it to be used in much higher doses than traditional radiation treatments.

Proton radiation therapy was found to be successful in cases where tumors had not been completely removed, obtaining a control rate at the local site of 85-100% with only small late term effects. Additionally, local control rates of skull base chondrosarcomas when treated with a combination of surgical resection, either total or partial, and follow up proton radiation therapy were at 94%. These stats put the survival rate of the combination of surgical resection and proton radiation therapy much higher than the five year survival rate of conventional chondrosarcoma, which was deemed to be 70%.

However, despite its clinical success, proton radiation therapy has not been expanded into a major treatment option, currently only being practiced at a single location, the Paul Scherrer Institute.

2-Methoxyestradiol


Similar to radiation, many chemotherapy treatments are ineffective against chondrosarcomas. There are a few theories as to why chondrosarcomas are resistant to chemotherapies, one being that they have a multidrug resistant gene, “resulting in resistance to doxorubicin in vitro ”. There is another theory that the resistance is due to a large extracellular matrix surrounding the chondrosarcoma and a relative lack of vascularity, meaning there are few veins within the tumor itself. These factors would decrease the access the chemotherapy drugs have to the tumor, since they would have to diffuse over large distances in order to reach their targets.

2-Methoxyestradiol, however, is a fairly new chemotherapy drug that is still being tested and is showing promising results in preliminary studies on chondrsarcoma. 2-Methoxyestradiol was found to stop cancer cell replication and induce apoptosis with specificity that favored action in tumor cells over healthy host cells, meaning 2-Methoxyestradiol can essentially target cancer cells in its treatment. Additionally, 2-Methoxyestradiol seems to act only in cells that are actively dividing, meaning that it is essentially able to target cancer cells directly as cancer cells divide so much more often than their surrounding host tissue. Recent studies have found that in mice, rats, and dogs, the toxicity of the host was very low even at high doses of 2-Methoxyestradiol. In a study of 2-Methoxyestradiol’s toxicity levels, rats and dogs were exposed to doses twelve times what is recommended for tumor treatment and there was “no drug-associated mortality” and no signs of toxicity other than weight loss, which was only observed in rats. The fact that 2-Methoxyestradiol has such a significant effect on chondrosarcoma cells while having minimal effects on healthy host tissue makes it a prime subject for future research into chemotherapy treatments for chondrosarcomas.

Because 2-Methoxyestradiol is related to estrogen, there were concerns about its safety, but 2-Methoxyestradiol did not show an estrogenic response, indicating that there was likely little to no risk of estrogen-related carcinogenic properties.

Rare Disease Information
Rare diseases are classified as diseases that affect less than 200,000 Americans. This lack of patients means that the support for those who are affected by the disease is severely lacking. The unfortunate thing about rare diseases is that when they are all combined, the number of people who suffer from so called rare diseases is nearly 30,000,000 in the US alone. This means that nearly one in ten people in the US has a rare disease. While the individual diseases may be rare, having a rare disease certainly isn't, and this is why the lack of support for those who have rare diseases needs to be addressed.

On Campus Support
Currently, Chapel Hill's campus does not have a direct support option for those who suffer from a rare disease or the family members of those who do. While the university does have the | Family Support Program through the School of Social Work, this program does not have a specialized section for those who have or are related to those who have a rare disease.

Future Support Programs
While the university does offer support programs for a wide variety of conditions, it does not offer any major support options for those with rare diseases. The university should not ignore those with rare diseases just because there may not be that many who need the support. While it would not be feasible to form a support group for each individual rare disease, having a general group for those with rare diseases to discuss the unique hardships that having such a disease entails would be a step in the right direction. Simply offering better information on rare diseases on the Family Support Program website would be beneficial to those who are affected by rare diseases, as it currently has almost no information on it compared to the other disorders that are supported by the program. Allowing students access to more information about these diseases may help alert students who may have these diseases and have gone undiagnosed. Additionally, having more information on campus could help campus medical staff with diagnosing these diseases, which may not be seen often because of their rarity.

Further Readings
[NIH-Chondrosarcoma] This website contains some general information about chondrosarcomas, and can allow you to better understand this disease.

[UNC Family Support Program] This is the Family Support Program website that is associated with the UNC School of Social Work. It has information for support groups for a wide variety of issues and other useful information.

[National Organization for Rare Disorders] This website has information for patients and families of patients with rare disorders.

[Family Support Network] This website allows families with children who suffer from rare disorders to connect with one another for support or information.

[World Health Organization - Coming together to combat rare diseases] This gives some insight into other rare diseases and their prevalence around the globe.