Wednesday, February 4, 2009

Quintuple negative?

The phrase 'triple negative' to describe my breast cancer has only been used for the past 3 years. Before that, bc was divided into 2 main groupings: estrogen positive and estrogen negative. Survival sadly (for me and my negative sisters) differed considerably between the two groups but now, with early chemo the gap is closing. Overexpression of the her2 protein in certain cancers and a drug targeting it (herceptin)has been known for at least 10 years. But the following steps have to occur before a promising cancer drug can be approved for use:

1. Proof of concept. Does the drug work in vitro? For Herceptin, does it stop the growth of cell cultures that over express her2?

2. Animal models. Does it stop the growth of her2 tumors in animals? There is a huge gap between what happens in vitro and in vivo. This fact has been drummed into me over and over in my career as a medicinal chemist.

3. Toxicity studies. Benefits better outweigh risks. Fortunately a lesser standard is held for cancer drugs vs an anti-depression drug. Still these studies can take years.

4. Clinical trials: the drug has to show a benefit in patients (metastatic breast) over everything else has been tried.

5. If the drug is found better than anything else for metastatic cancer patients, it can be approved for those patients only. It can then be tried for node-positive early breast cancer.

6. If survival is increased in early node-positive breast cancer over the standard treatment, then it can be tried in early node-negative breast cancer and eventually approved for use in those patients.

All those steps take years. I am hoping that the term 'triple negative' is short-lived. That other growth factors are identified that make such a big difference in survival and are targeted. Some have been identified and drugs targeting them are on trial such as Avastin for VEG-F. Did they test my tumor for VEG-F? Or any other factor? No and it annoys me. But meanwhile the database used to predict my survival included the her2 positives. Also it included node negative women who did not receive Taxol. Taxol has only been recently used for early node-negative cancer. I'm still trying to pin down how recently. I do know that it isn't as useful for estrogen positive tumors.

Maybe I am just grasping at straws trying to console myself that my chances for long term survival are greater than the 70% the computer spit out. They are but how much more is very hard to quantitate.

Too cold to walk today. I'll go for a longer walk than usual tomorrow with Deb. Resolved a few insurance issues (maybe-what we are promised isn't always the reality).

Naomi got to start in last night's game but played so poorly.. The dreaded grades came in but they weren't bad as I feared. Naomi had a hint as the coach gets them before I do (how is that right?). He had given the team a lecture about certain individuals bringing the team average down and then looked at Naomi, but it isn't Nay for a change-congratulations to her.

As for Naomi, she has been behaving much better recently. If she maintains a certain average, we will give her our oldest car. She will need one next year for sure but she is motivated and trying very hard to keep on top of schoolwork.

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