Back before the surgery, when I was looking for a second opinion about treatment options and researching who the best surgeons in the area would be, Grand Rounds located the very impressive Dr. Manish Aghi to provide me with a second opinion about treatment options and answer some of my questions.
I was just reviewing the answers he sent over at that time, some of which are pretty relevant to my current questions:
“If the mass is a chondrosarcoma, could you explain what the next steps in my treatment would be after surgery? Specifically, Dr. Almefty suggests that post-operative radiation is not necessary in low grade chondrosarcoma, where as Dr. Bloch argues it is necessary to lessen recurrance risk. What is your explicit recommendation, including any evidence to support your recommendation? If radiation is recommended, when should it be performed?
I concur with Dr. Bloch – I believe the data support postoperative radiation for low grade chondrosarcoma. Dr. Bloch’s evidence is stronger since it is derived from something called a meta-analysis, which summarizes multiple articles. Dr. Al-Mefty’s conclusions on the other hand are from a single center’s experience with 109 patients. In addition to Dr. Bloch’s data, a recently published article on which I am a co-author (referenced below), summarizes the impact of radiation therapy for skull base chondrosarcoma over the years 1973-2009. It concludes that radiation is likely beneficial in skull based chondrosarcomas (unfortunately there are too few cases to say this with absolute certainty).
My patients typically start proton therapy within 2 to 3 months following surgery. While there is no true benefit to waiting, it is important to give the brain and surrounding structures time to recover from the surgery before starting radiation.
My physicians said that they will be unable to remove the entire tumor. Why? Will this affect my how well I do after surgery? Also, the surgeons at the University of Washington have suggested that with newer technology they will be able to remove the tumor in a single surgery (craniotomy) versus two surgeries (which is proposed at Virginia Mason). Could you comment on which approach might be better and why?
Inability to remove the entire tumor occurs when tumors involve spaces that are risky to access surgically, such as when the tumor wraps around arteries or when tumors are in inaccessible places. From your MRI reports, the reported size of the tumor suggests that there is a high probability they will find an artery encased by tumor or tumor in an inaccessible area. Incomplete versus complete tumor removal does not affect immediate surgical recovery, but incomplete tumor removal increases the risk of tumor regrowth later on down the road.
In terms of the type of surgery performed, if your surgeon feels that maximal safe resection can be achieved in one surgery, this option is always better than two surgeries. That being said, we have found that about one third of clival tumors benefit from a second surgery while two thirds can be treated through only one surgery (this is based on unpublished observations).
What will determine if I need radiation or chemotherapy following surgery? Will radiation or chemotherapy help prevent a recurrence of the tumor?
As mentioned earlier, I feel radiation is necessary to try to prevent recurrence for chordoma and chondrosarcoma, and I recommend radiation after surgery regardless of the outcome of surgery (whether they feel they have removed the entire tumor or not). Chemotherapy is typically reserved for if there is a recurrence of the tumor (the tumor regrows after surgery and radiation).
If I require radiation, my treating physician mentioned it might cause hearing loss in my left ear. Is there a way to prevent this from happening?
Hearing loss is a definite risk because the tumor is close to the nerves that control hearing. The type of radiation given to treat these tumors will carry a risk of hearing loss in the left ear, and unfortunately there is little that can be done to prevent this.
While I’m sure the past several weeks have been difficult on you, I hope things go smoothly for you and that you find support among friends, medical caregivers and family.
Recommendations from your expert
- What research data exists, if any, about outcomes for various treatment options for my specific type of chondroscarcoma: grade II myxoid chondrosarcoma?
- Is there any really solid research about the timing of proton radiation therapy? Will it make a difference to wait a year, or is it important to do it right away? Does the timing impact outcomes?
- If recurrence happens, how likely is it to be a higher grade or worse/different subtype than currently exists?
- What kinds of outcomes result from proton radiation therapy in skull base tumors, and what are the likelihood of those outcomes happening given the location of my specific tumor, both original and remaining?
If any of you are able to locate legitimate medical journal articles related to any of these questions, I’d appreciate knowing about them. I lean toward double-blind studies with large sample sizes, although I realize the large sample sizes might be tough to find with such a rare type of cancer.
Thanks for keeping up with what I realize must be one of the more unexciting blogs on the planet, everyone! I hope you have a good weekend.