Cancer Rates in Andover are Within Expected Range

Study hampered by small sample size, limited data

October 27, 2014 • Saved under News
By Vicky Mishcon, for the Beacon

A panel of experts from the New Hampshire Department of Health and Human Services (DHHS) and Dartmouth College met with Andover residents on October 22 to present the results of a cancer cluster study for Andover.

The study was initiated, following a request by the Board of Selectmen, after several residents of Andover Village voiced concern about the number of cancer cases in the village area.

The presenters were:

  • Thomas Lambert, Chief of Health Statistics and Data Management for the DHHS.
  • Dr. Judy Rees, Director of the New Hampshire State Cancer Registry and Assistant Professor at Dartmouth College.
  • Dr. Monawar Hosain, New Hampshire State Cancer Registry Epidemiologist for the DHHS.

To begin, some general facts about New Hampshire’s cancer burden were shared:

  • New Hampshire has the highest rate of cancer in the United States.
  • Cancer has been the #1 leading cause of death in New Hampshire since 2005.
  • 75% of cancers occur in people over the age of 55 years.
  • The median age of people in Andover is 48 years, which could be a contributing factor to the number of cancer cases.
  • The total number of invasive cancer cases in Andover from 2005 to 2011 is 96, compared to 52,474 statewide during the same period.
  • A suspected cancer cluster is more likely to be a true cluster if it involves: a large number of similar types of cancer, a rare type of cancer, or an increased number of cases of a certain type of cancer in an age group not usually affected by that type of cancer.

The results of the analysis for Andover showed that the various cancer rates are within the range of what is expected in comparable populations in New Hampshire. (The analysis breaks down these rates by type of cancer.) These results are reassuring, as they suggest that the most likely explanation for these observations is random chance as opposed to environmental factors.

But this is not to suggest that it is not possible to reduce the risk of cancer. On the contrary, most cancer incidences can be related to our behavior, such as smoking, excessive sun exposure, heart disease, and diabetes.

New Hampshire has very good reporting and collection of data on cancer cases. Therefore, there is a high level of confidence in the data that exists.

However, the presenters explained that due to the small size of New Hampshire towns, it is very difficult to obtain strong statistical results in a small geographic area within a town, or for a specific type of cancer when the number of cases is small.

Also, the information that they are able to collect from the cancer registry and from hospitals is very limited in scope. For example, they have no way of knowing how long a person has lived in a community that they are studying, or what each person’s workplace environment is like.

A long question and answer session followed, with some residents still concerned about the incidence of cancer and the obvious limitations of a statistical analysis-type study.

Cindy Benson will be offering a presentation on breast cancer with a breast cancer surgeon from Dartmouth- Hitchcock Medical Center and information on treatment options and general education. Time and place will be announced.

The full Powerpoint presentation of the study results is available here.