Endocrine Abstracts

Purpose: To evaluate if patients with low- or intermediate-risk differentiated thyroid cancer (DTC) can be discharged to primary care.

Material and Methods: The clinical records and evolution of 346 patients with DTC who had undergone surgery between 1995 and 2020 with a follow-up after a mean of 7.6 ± 6.1 years were retrospectively reviewed. All had a low or intermediate risk of recurrence as defined under the 2015 ATA risk stratification system and a minimum follow-up of one year. Biochemical (thyroglobulin) and structural (imaging findings) yearly evaluations were used to dynamically classify patients based on their response to treatment as excellent, indeterminate, biochemically incomplete or structurally incomplete. Primary outcome was the assessment of disease recurrence (biochemical or structural) as defined under the 2015 ATA guidelines.

Results: Throughout follow-up, 14.7% (n=51) patients presented disease recurrence. When classified by initial risk of recurrence (low or intermediate) it was seen that 4.53% (11/243) of low-risk patients and 39.81% (41/103) of intermediate-risk patients presented recurrence. This difference was statistically significant (P<0.0001) with no statistically significant difference in follow-up times between the two groups (P=0.34). Moreover, when examined in terms of response to treatment, it was seen that only 1% (2/193) of low-risk patients with an excellent response to treatment presented recurrence. The majority of patients presented disease recurrence in the first five years of follow-up, 98% (50/51), the mean time to recurrence being 9.38 ± 18.68 months.

Conclusions: Low- and intermediate-risk DTC patients exhibiting an excellent response to treatment have a minimal recurrence risk that could offer the possibility of discharge to primary care follow-up after a five-, or a more cautious ten-year, follow-up period. The 2015 ATA risk stratification system proves to be an accurate and useful tool for the prediction of recurrence both postoperatively as well as at specific points during follow-up.