Cancer mortality in the United States may be underestimated, because deaths within a month of surgery for solid tumours are recorded as deaths related to treatment, according to researchers.
Dr H Gilbert Welch and Dr William Black of Dartmouth Medical School in New Hampshire argue that cancer mortality should include not only deaths from cancer but also deaths caused by treatment for cancer. In the they report that 41% of deaths within a month of treatment for cancer were attributed to another cause, and thus cancer mortality was underestimated by 0.9% and that many deaths after a month were also not counted as deaths from cancer. Their study has implications for cancer statistics, success in treating cancer, and early screening. However, their study did not go unchallenged—an accompanying editorial says that Welch and Black's proposals may be impractical.
The authors say there are no guidelines for classifying deaths related to cancer treatment, and all deaths within the first month after surgery should be considered as deaths from cancer.
Using data from the National Cancer Institute's surveillance, epidemiology, and end results programme for 1994 to 1998, they determined the proportion of deaths not attributed to cancer for 19 common solid tumours.
Had those deaths been reported as cancer deaths, recent decreases in cancer mortality would have been less. They say that misclassification of cancer deaths has increased over the last 20 years.