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 Accuray (NASDAQ:ARAY), the developer of radiosurgery and radiation therapy systems such as CyberKnife and TomoTherapy, jumped as much as 16% after reporting better-than-expected second-quarter results.

So what: For the quarter, Accuray delivered a 20% increase in year-over-year revenue to $93.6 million, which included gross product orders of $80.3 million, a 102% increase over the year-ago quarter. The company also ended the quarter with a product order backlog of $362 million, a 30% jump from this time last year. Most importantly, net loss shrank dramatically to just $0.07 per share from $0.40 in the second quarter of fiscal 2013. By comparison, Wall Street had expected a much wider loss of $0.20 per share. On the heels of its strong product sales, Accuray also boosted its 2014 revenue guidance to a new range of $340 million to $350 million from its prior forecast of $325 million to $345 million.

Now what: I know I say this a lot with medical device companies, but Accuray is one of those companies with a really "cool" lineup of products, but that's failed to meaningfully capitalize on those products to drive bottom-line growth. I'm encouraged by Accuray's growing product backlog and narrowing losses, but the skeptic in me won't be fully convinced until I see consistent profits. Given that Accuray shares have nearly tripled from their April 2013 lows and the company still isn't profitable, I'm skeptical of how much extra upside might be left in the tank.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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