Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of biotechnology company Synta Pharmaceuticals Corp. (NASDAQ: SNTA) soared a whopping 43% today, after results from a mid-stage study of its drug ganetespib in breast cancer patients warranted an expansion of the study.

So what: Synta said that ganetespib helped enough patients with triple-negative breast cancer to support a second stage of the trial, reinforcing optimism over the drug's blockbuster potential of treating different types of cancers. In fact, according to the American Cancer Society, triple-negative breast cancer is particularly fast-spreading and difficult to treat, so the surprising results should help Synta garner some big-pharma partnership support as well.  

Now what: In the next stage of the trial, Synta will also evaluate ganetespib in combination with a weekly cancer drug called paclitaxel.

"The favorable safety profile, clear single-agent clinical activity, and strong rationale for combination therapy suggest ganetespib may have broad potential utility in breast cancer," said Vice President of Clinical Research Dr. Iman El-Hariry.

So while Synta remains just too volatile for average investors (the stock is still off about 40% from its 52-week highs even with today's surge), biotech experts might want to follow the story more closely.