Victims of WTC cancer reportedly number in the thousands, many of them first responders or volunteers who worked in and around ground zero following the collapse of the World Trade Center.

A cancer diagnosis can develop many years after initial exposure. While research has not yet identified fully how the process works, being exposed to toxic chemicals and materials can affect the body over the course of time, ultimately leading to many different forms of cancer.

Numerous 9/11 volunteers and responders have developed a broad range of conditions years after the event.

According to USA Today, a new study completed by Rutgers University reveals that head and neck cancers are some of the most commonly diagnosed medical issues that follow such a diagnosis. The researchers identified that diagnoses of the head and neck cancer increased by over 40 percent in a group of WTC employees and volunteers across a four year period.

These emerging health risks and growing diagnoses of various forms of cancer led to the establishment of the Victims Compensation Fund. This fund exists to provide financial support to those people who have been diagnosed with cancer because of the toxins they inhaled or came into contact with when working in or around ground zero.

The WTC cancer study found that carcinogenic exposures, such as those that occurred at Ground Zero, could increase or add to the effect of other personal risk factors such as heavy alcohol use and oral HPV infection or tobacco smoking.

The research team looked at neck and head cancers diagnosed from 2003 to 2012 with 73 different volunteers and first responder workers enrolled in the WTC health program. They identified a 40 percent increase in the diagnosis of those particular diseases between 2009 and 2012.

Study results were published in the International Journal of Cancer.

Many forms of WTC cancer take years to develop and that is why more people have been seeking compensation from the 9/11 Victims Compensation Fund in recent years. Some people who were working in the area are just now beginning to experience the long term health effects of working near the collapse of the Twin Towers. Many first responders inhaled toxic materials such as glass fibers, asbestos, cement, dioxin, and other chemicals.

According to NBC News, nearly two decades later, many of these victims are still paying for the time they spent attempting to save the lives of others.

The World Trade Center Health Program covers a number of different disorders including cancers. Only certain cancers are covered by the WTC Health Program, including those that affect blood and lymphoid tissue, the digestive system, the esophagus, stomach cancer, breast cancer, and head and neck cancer.