News wires are carrying the story that a doctor has observed a number of cases of multiple myeloma in workers from the World Trade Center site.
First, it is important to note that this is an early report, and such epidemiological clusters could be the result of many things other than a causal link. It could be observational bias: those exposed at the WTC are watched much more closely than the general public. The report apparently doesn't say how many cases were seen, only that the cases occurred in younger individuals.
If this unfortunate observation turns out to represent a new cluster, it will be interesting to find out to what degree the patients have genetically similar tumors. Multiple myeloma often results from translocations which generate 'always on' growth signals in terminal B-cells, the cells which normally produce antibodies in response to challenge by a foreign substance. I don't believe there is much evidence linking specific translocations or other genetic abnormalities with particular sources of multiple myeloma -- particularly since little is known about the causes of myeloma other than it is most frequent in the elderly. If particular translocations are prevalent in these cases, then that may be helpful in treatment -- myeloma is probably on the cusp of having treatments focused on genetic subtypes, due to many personalized medicine studies (including the one I had peripheral involvement in). There is also a lot of pharmaceutical company interest in myeloma, a situation which wasn't very true a decade ago.
The witches brew of dust, asbestos, smoke and other chemicals will surely take a toll on those who served their country in that time of need. The best we can hope for is to try to get a little ahead of the curve.