The final Kaddish recited in the prayer service (either Kaddish Al Yisrael, or Kaddish Yeheh Shelama) is customarily recited by mourners. If there are no mourners, then the Kaddish is usually recited by somebody whose mother or father had passed away, Heaven forbid.
It sometimes happens, however, that there is nobody in attendance to say Kaddish – no mourners, and nobody who had lost a parent. What should be done in this situation?
I recall hearing Rabbi Max Maslaton teach that Kaddish is part of the prayer service, and it must therefore not be skipped, just like no other part of the prayer service may be skipped. Beyond the benefit the Kaddish recitation brings to the soul of a departed parent, it also is intrinsically significant as an important part of the Tefila. Therefore, Rabbi Maslaton said that somebody who is not prepared to recite the final Kaddish should not serve as Hazzan, because if there is nobody in the congregation to recite the final Kaddish, then the Hazzan should recite it.
In practice, however, there are many people who feel uneasy about reciting Kaddish if both their parents are alive. I recall as a student in Magen David, where I would often serve as Hazzan, Hacham Baruch Ben-Haim told me to ask my father if he allowed me to recite the final Kaddish. I did, and my father did not permit it. This feeling is quite common, and one whose parents do not feel comfortable with him reciting this Kaddish should not do so. Inherently, however, there is no concern whatsoever about this Kaddish recitation bringing "bad luck" or posing any sort of danger to the parents. Therefore, unless the Hazzan's parents have strong feelings about the matter, he should recite the final Kaddish if nobody in the congregation does.