By Jim Woods on March 12, 2013

This market keeps going higher and higher, and over the past week, weve seen five consecutive all-time highs in the behemoth-cap Dow Jones Industrial Average. The index is up about 10% so far this year, and its been one of the best first 10 weeks of a calendar year in a very long time. And while the Dow has been grabbing much of the medias attention this year, its not the only major market average thats soared to all-time highs in 2013.

The small-cap Russell 2000 index also has had a stellar year, and is higher by about 11% so far in 2013. Now traditionally, the small-cap segment of the market is much more volatile than large caps, and though the representative index performance data might not reveal this, digging into the weeds of the Russell 2000 certainly demonstrates the volatility.

Since the beginning of the year, the average percentage loss of the 10 biggest losers (year to date through March 11) in the Russell 2000 is nearly 55%. Even more impressive are the biggest winners in the index. The top 10 percentage gainers year to date average a gain of more than 105%.

If you own any of the stocks on the extreme ends of the small-cap performance spectrum, then now may be the time to sell your losers and rotate that capital into better-performing stocks, and also the time to sell your big winners and lock in those giant trading gains.

The table below shows the biggest losers in the Russell 2000 so far in 2013.

Topping this ignominious list is biopharmaceutical firm Affymax (NASDAQ: AFFY ). Small biotech companies tend to be feast or famine. One big drug trial that fails to yield expected results can mean a big sell-off. Conversely, promising results from a drug trial can mean huge gains for these stocks. Other biotech losers on this list are EnteroMedics (NASDSAQ: ETRM) and Rockwell Medical (NASDAQ: RMTI ) .

These stocks represent the most unloved companies in the small-cap segment right now, and that means any trading capital committed here needs to be freed up in pursuit of more fertile ground.

The flipside to this coin are the biggest winners so far this year. These are stocks that have seen a remarkable run higher, and though there could be more upside for any and/or all of these stocks, its more likely that the big money has already been captured in these small-cap winners.

The table below shows us the best of the best so far this year.

Interestingly, four of the top 10 stocks are in the biotech sector. This fact supports my earlier statement that the small-cap biotech segment is feast or famine. The biggest winner in the Russell, Keryx Biopharmaceutical (NASDAQ: KERX ). is up more than 181% in just the first 10 weeks of the year. That is the kind of spike every trader dreams about.

If you are long KERX, or if you have been fortunate enough to own any of the stocks on this list, profit-taking is not only justified, its highly advised. As you know, its hard to make big money in stocks even during the most bullish market. So, dont let your gains evaporate in the pursuit of even more upside. Bank your profits in these stocks, and redeploy them to other stocks you deem likely to give you another big win.