In response to The increasing incidence of small thyroid cancers: Where are the cases coming from ?

The letter from Dr. Wang et al. is thoughtful and complete, and adds considerably to the discussion of the problem of incidentally detected thyroid nodules and cancers. One area in which we differ in opinion is the importance of cancers larger than 1 cm. In their letter, Dr. Wang et al. argue that because some cancers are T2 and will become larger later, the patients will have a poorer prognosis. This belief is an important fallacy of survival statistics that we often forget. First, this assumes that a larger cancer will necessarily spread and cause the death of the patient. A cancer of 2 cm is not definitely going to cause a problem for the patient, any more than a 0.9-cm cancer is definitely not going to cause a problem. Second, the concept of survival can be misleading because finding out about a cancer earlier results in a survival calculation in which it appears that survival is longer. But it prolongs survival only because we knew about the cancer sooner, not because we treated it any better. As surgeons, it is important for us to understand how our patients’ thyroid findings were identified, and to consider this information in our decision making. We should include this information in our discussions with the patient about the best way to manage their thyroid finding in their particular case. Our hope is that our article provided information about the classification of such findings. Now with your letter and our reply, we have a further discussion of the meaning of such findings, which can only help the surgical community advance the discussion of the problem of overdiagnosis of thyroid cancer.