PISCATAWAY - Dr. Iris Udasin has hundreds of patients sickened by their time spent at Ground Zero.

According to a federal review of the latest research on 9/11 illnesses, a cancer-link has not been proven. Explaining why, to lay people, has kept Dr. Udasin busy.

Dr. Udasin says the review reflects only a small number of cancers that have been written about in peer-reviewed articles, not a full account of all the Ground Zero heroes who have been diagnosed or who have already died from cancer.

Dr. Udasin says she can personally believe there's a link between Ground Zero toxins and the cancers she sees among first responders, but believing is not proving.

Study: Cancer not among diseases from Ground Zero