Seth's Info

It’s the end of a beautiful weekend here. We attended the State College Spikes game last night (the Spikes are a recent addition to State College, they are a Class A affiliate in the St. Louis Cardinals organization). The stadium is brand new and very nice.

My esophagus is acting up again, today is the worst it has been in some time. One of the drugs I am taking, doxorubicin, is known to “recall” previous side effects from radiation treatment. So every time I take the drug, it tends to produce similar side effects from when I had my radiation treatment. One person on the Sarcoma list serve we monitor likes to call radiation the “gift that keeps on giving” for this very reason.

I have never previously discussed the specifics of my particular cancer diagnosis, Malignant Peripheral Nerve Sheath Tumor, or MPNST. It is a subtype of a group of cancers known as Soft Tissue Sarcoma. Sarcoma, as a group, is relatively uncommon in the US, comprising about 1-2% of diagnosed cancers. MPSNT comprises about 5-10% of sarcoma diagnoses. If you do the math, this approaches 500 to 1,000 persons per year in the US.

One of the difficulties in researching MPNST is that it is a relatively recent term, replacing what were previously known as malignant schwannoma, neurofibrosarcoma, and neurogenic sarcoma. Additionally, because it is an uncommon form of cancer, the number of research studies and trials is limited.

The body’s nervous system is divided into the central nervous system and the peripheral nervous system. The central nervous system is comprised of the brain and spinal cord (which carries messages to the brain), while the peripheral nervous system is comprised of the vast network of nerves that carry messages to and from the central system. The cells that carry these messages are called neurons. One of the components of a neuron is the axon, a long fiber which carries messages away from the cell (see diagram below). The axon is protected by a lipid layer known as the myelin sheath. It is the cells of this nerve sheath that mutate in MPNST. (Interestingly, it is the destruction of large portions of the myelin sheath that characterize Multiple Sclerosis.) As evidenced by my own case, MPNST can be difficult for a pathologist to diagnose conclusively. My original pathologist diagnosed my cancer as leiomyosarcoma, but subsequent studies have indicated MPSNT as being much more likely.



One other interesting note -- up to 50% of MPNST diagnoses are associated with a genetic condition called Neurofibromatosis, also known as von Recklinghausen disease. I don’t have that genetic condition, so I fall in the half of cases with less certain causation. Since my original tumor was located with my abdominal muscle, I can only assume it was a nerve sheath within that muscle that mutated and grew.

If you are looking for more detailed info on MPNST I can recommend these 3 links

Liddy Shriver MPNST Page
Radiographics Case Study
Maxilofacial Center Page on MPNST

We're heading down to the Harrisburg area on Tuesday and Wednesday, and hoping to make it to Hershey Park. Hope everyone has a great week.

Seth