I haven't seen any studies done on the cigar industry workers, I have however seen a couple done on cigar smoking in general. For the most part the ones I've seen suggest that cigar smoking is less dangerous than cigarette smoking while done in moderation (usually no more than 1 per day, sometimes 2 depending on the study). There have also been studies done indicating that cigar smoking in moderation can actually increase lifespan. Key factor in that seemed to be that cigar smoking was usually done in a peaceful environment and for relaxation, and thus helped to reduce stress. Also if I recall properly, nicotine can help lower blood pressure by acting as a depressant. Mouth and Throat cancer are possibilities among cigar smokers who do not inhale, however, throat cancer is a reduced risk over cigarette smoking and inhaling. Also cigars tend to contain less additives than cigarettes, and be less chemically addictive.
I'm by no means a doctor, but these are just some things I've read/learned over the past couple of years. I'm sure there are studies that contradict some of this info, because you can always find studies on either side of issues, especially ones like this.
My 2 cents would be that cigar smoking probably puts you at an increased risk over non-smokers, but less than cigarette smokers. But in moderation is very unlikely to cause any severe health problems. And we're all aware of the risks involved, and old enough to make the decision to smoke or not to smoke. Just my thoughts on the issue.