FNA Mapping: A Tool for the Trade

Do you have a favorite tool? Maybe a great cooking pot or utensil that really works for you. Possibly a shiny, worn and weathered but perfectly performing baseball glove, or a dinged and pockmarked surfboard that handles virtually every swell. Whether you’re a carpenter and fan of curly maple, or a car hobbyist who likes to hear things “gurgle and roar,” you probably have a tool that just feels right and works like nothing else. A workhorse of the toolbox. Old reliable.

Two Men in Need

I have one such tool, and use it all the time at work. No, it’s not a scalpel, although I very much appreciate what they can do. Allow me to explain.
A young man came to see me because he is sterile (azoospermia) and he wants children. Told that there was a good chance that he may have tiny pockets of sperm in his testicle that can be used with assisted reproduction to have kids, he had gotten a 3-hour, invasive surgical procedure call “testicular microdissection,” which failed. He asked me whether I might be able to find sperm with my special tool, and I did.
Another young man saw me after being told that he had a few sperm in his ejaculate (cryptozoospermia) but was unable to conceive with assisted reproduction. Apparently, on the day he needed those few sperm for IVF, there was none found in the ejaculate. On that same day, he underwent a testicular sperm retrieval and no sperm were found either. “How could this happen?” he asked, “Since there HAS to be sperm SOMEWHERE in there, right?” I pulled my special tool out of its box, and sure enough found that spot of sperm in the testicle.

A Tool Among Tools

Fine needle aspiration (FNA) Mapping is now almost 20 years old. Over that time, it has evolved to become a workhorse technique for finding sperm in men with azoospermia. But what happens when you throw the book at it and examine difficult cases like the two patients I described? Recently, I presented our research findings at the Pacific Coast Reproductive Society Annual Meeting on precisely how good FNA Mapping is in finding sperm in cases of failed microdissection and intermittent cryptozoospermia.
I don’t know how many reproductive urologists tackle these extremely challenging cases, but I do know that very few have ever published their findings. In our series of 65 men whom had failed microdissection TESE procedures from around the world, FNA Mapping subsequently found sperm in 29%. And in 36 men with cryptozoospermia, among which almost half had also had surgical sperm retrievals that failed, FNA Mapping subsequently found pockets of testicular sperm in 78%. Not a bad showing in the hardest of cases.
As with many trusted tools, they continue to earn our trust not only because of their reliability, but also because they deliver when challenged anew. In the words of author James Collier: “Success is the result of small efforts, day in and day out.”