One in three Americans will get cancer in their lifetime. When high numbers of diagnoses occur in a community, people fear cancer clusters. Many Ohioans are looking into cancer clusters, including citizens from Clyde and Port Clinton. Unfortunately, the high number of cases people notice in communities can often be attributed to the high rate of cancer in the United States.
The Ohio Department of Health recently completed a study to determine if cancer incidences among Port Clinton residents are higher than expected due to chance alone. The study focused on 503 cancers diagnosed for the years 1996-2007 and 267 cases diagnosed in 2002-2007.The majority of these cancers were cancers of the lung and bronchus, female breast, prostate, colon and rectum. These cancers are the most common in Ohio and the United States. Currently many of the Port Clinton cancer incidences have been blamed on smoking. But many residents harbor suspicions around the High School playing field, believed to be built on top of an old sewage disposal.
The Center for Health, Environment and Justice also released an assessment for the Port Clinton cancer cluster. Their assessment found the city experiences a 9% higher than expected incidence of all cancer types.
It is very difficult to attribute a cancer to anything other than known risks (diet, lack of exercise and smoking). Often cancer spikes are attributed to chance alone, especially in small populations. The conclusion of the Ohio Department of Health study concluded that the cancer rates in the Port Clinton area were higher than expected due to chance alone. The cause of each cancer case was undetermined by the assessment.
Cancer clusters are very difficult to prove, particularly in small populations such as Port Clinton. Small studies often result in an inability to achieve statistical significance, especially for rare cancers. Of particular concern is the address given. The address at the time of diagnosis is often used, and may not be the person’s primary residence throughout their lifetime.
Cancer is also a complicated disease incorporating over 200 different diseases, each with different risk factors, latency, course of disease and probability of survival. For example, thyroid cancer is three times more common among females than males. In addition, several of the cancers can be attributed to smoking (lung and bronchus and pancreatic)
Thyroid cancer was of primary concern in the ODH study. Thyroid cancer can be caused by inherited medical conditions, exposure to high levels of radiation, or a diet low in iodine. Eight thyroid cancers were diagnosed in the study period, twice the expected amount.