Bloomberg reported last week that University of Pennsylvania researchers are investigating the apparent incredible success of dogs in detecting ovarian cancer early. One dog named Tsunami had a better than 90% success rate in identifying ovarian cancer from tissue samples, which is an incredible result, and she isn't the only one -- a large study found that some dogs were 98% accurate in identifying prostate cancer from urine samples. Of course, more research and testing need to be done, but these are definitely interesting and exciting findings.

Unfortunately, there's no way to invest in cancer-sniffing canines. However, for investors interested in putting their money into early cancer detection, there are some interesting companies that are working to improve our early detection tools.

Exact Sciences (NASDAQ:EXAS) is developing a test called Cologuard, which is a noninvasive, stool-based colorectal screening tool. Cologuard is not mean to replace colonoscopies, but rather to serve as an adjunct to them. With strong clinical data (a 10,000 person phase 3 trial showed that the test successfully identified colorectal cancer 92% of the time) and peak sales estimates in the $1 billion to $2 billion range, this is a test -- and a stock -- worth watching. And Myriad Genetics (NASDAQ:MYGN) has a variety of hereditary cancer risk assessment tools, including Colaris for colon cancer, Melaris for melanoma, and perhaps most famously its BRACanalysis for breast and ovarian cancer. With last quarter's molecular diagnostic testing revenue up 19% to $176 million, this could be an interesting stock to watch.

In the video below, Motley Fool health care analysts Michael Douglass and David Williamson discuss canines and the interesting opportunities Exact Sciences and Myriad Genetics have in the oncology field.