A Big Challenge
According to the reported prevalence rates, some 16 million people in Germany are living with thyroid nodules. In spite of a slightly falling trend, this means about 300 affected patients for every GP. This situation presents a big challenge for all general practitioners and specialists in internal medicine who are working in primary care. Rational treatment strategies can be developed only if insights from clinical epidemiology are also taken into account.
We find ourselves confronted with a dilemma: the search for clinically relevant thyroid malignancies is akin to searching for a needle in a haystack. Neither laboratory diagnostics nor optimized thyroid sonography nor scintigraphy nor fine needle aspiration biopsy are suitable for diagnosing thyroid malignancies efficiently, even if the technology is excellent and the associated specificity and sensitivity are high. Owing to the low prevalence and their varying presentation on imaging procedures, the positive predictive values for thyroid malignancies—and this is the crucial issue—are way too low, even after fine needle aspiration biopsy. For each thyroid malignancy found during surgery, 50 patients would have to be operated on unnecessarily (1).
So what is there to be done? To desist from using a diagnostic technique that goes beyond specific history and clinical examination—such as has already been discussed in the US—is undoubtedly thought provoking (2). We should not underestimate, however, that the interventions mentioned in the article cause iatrogenic harms that are quantitatively and qualitatively relevant (3). We need to rethink how to deal with patients with thyroid nodules, and such a rethink would prompt a conclusion that is totally different from that recommended in the article. It would make sense to make transparent the risk probabilities and balance the benefits and risk of medical measures and reach a shared decision with the patient.
Dr. med. Armin Mainz
Hausarzt/Facharzt für Innere Medizin, Korbach, email@example.com
Conflict of interest statement
The author declares that no conflict of interest exists.
|1.||Schicha H, et al.: Should all patients with thyroid nodules ≥ 1 cm undergo fine-needle aspiration biopsy? Nuklearmedizin 2009; 48: 79–83. MEDLINE|
|2.||Cronan J: Thyroid Nodules: Is it time to turn off the US machines? Radiology 2008; 247: 602–4. MEDLINE|
|3.||Liel Y, Fraenkel N: Brief report: Use and misuse of thyroid ultrasound in the initial workup of patients with suspected thyroid problems referred by primary care physicians to an endocrine clinic. J Gen intern med 2005; 20: 766–8. MEDLINE|
|4.||Führer D, Bockisch A, Schmid KW: Euthyroid goiter with and without nodules—diagnosis and treatment. Dtsch Arztebl Int 2012; 109(29–30): 506–16. VOLLTEXT|