Since the use of asbestos has been significantly limited in recent years, it may be tempting to assume that mesothelioma is no longer a major issue in America. But a report of 21 new cases from a single mining region show this is not the case. Though this story is not from Pennsylvania, it should serve as a reminder that mesothelioma often lays dormant in the body for years before it emerges.

The Minnesota Department of Health announced recently that it has identified 21 new cases of mesothelioma, the deadly disease connect to asbestos exposure, out of a group of 69,000 mine workers the agency has been studying since the late 1990s. That brings the total number of cases among workers from that specific mine to 101 diagnoses since 2003.

The sickened workers all worked in the state’s iron mining industry sometime between the 1930s and 1982. The mining industry frequently used asbestos in those years. One expert noted that cases of mesothelioma are likely to continue to appear until people who were exposed at work “age out” of the population.

Mesothelioma is a rare form of cancer found in the mesothelium, the thin layer of tissue that covers most of your internal organs. Most often affecting the tissue around the lungs, mesothelioma is particularly aggressive and deadly. For many patients, a cure is not a possibility.

Though it may be a long time after exposure that the cancer appears, victims and their families may still be able to receive compensation.