Incidence and dynamic risk stratification in differentiated thyroid cancer in a high-resolution clinic, 2002-2017

We evaluated the incidence, progression and the dynamic risk stratification in differentiated thyroid cancer (DTC) under follow-up in a high-resolution clinic (HRC).

This was a retrospective observational study on incident cases in the tumor registry from 2002 to 2017 and their evolution under follow-up in HRC.

A total of 444 patients (78.5% women, 52.1±14.9 mean years old) were DTC diagnosed from 2002 to 2017. The incidence rate of DTC increased from 5.2 to 25.7x10⁵ habitants/year in women and from 2.3 to 7.1x10⁵ habitants/year in men (P<0.0001). This increased incidence was not associated with an increment in the incidental papillary microcarcinoma diagnosed (from 29.4% to 32%). In those patients undergoing follow-up at the HRC (84% papillary carcinomas), 65.7% were classified as being at a low risk of recurrence compared to 14.5% at high risk. Of those, 88.8% classified as making an excellent response at diagnosis remained disease-free at the final follow-up visit. However, those patients with an indeterminate or structurally incomplete response at diagnosis evolved to an excellent response in 55.8% and 42.9% of the cases, respectively, compared to 14.8% of those with a biochemically incomplete response (P<0.001) CONCLUSIONS: The increased incidence of DTC is similar to results published previously in other countries. Dynamic risk stratification systems adequately classify DTC patients and assess diagnostic and treatment procedures, especially in low-risk subgroups.