Active Surveillance in Papillary Thyroid Microcarcinomas is Feasible and Safe: Experience at a Single Italian Center

Abstract

Context: The dramatic rise in the incidence of thyroid cancer over the last 30 years is largely attributable to the increasing diagnosis of papillary microcarcinomas (mPTCs). Current guidelines endorse an observational management approach in properly selected cases.

Objective: To evaluate the feasibility of active surveillance in mPTC in Italy, its impact on real life, and to identify risk factors of progression.

Design and setting: In 2014 we started a prospective-observational study of active surveillance in mPTC patients.

Patients: Included patients demonstrated a single Thy4 or Thy5 thyroid nodule, with largest diameter ≤1.3 cm, and no suspicious laterocervical lymph nodes by neck ultrasonography. Of 185 eligible subjects, 50.3% (93/185) enrolled in the observational management protocol while the others opted for surgery and were excluded from this analysis.

Intervention: Enrolled patients were followed with neck ultrasound at 6- to 12-month intervals. Disease progression was defined as the appearance of abnormal lymph nodes or nodule enlargement during follow-up. In these cases, patients were directed to surgery.

Results: Three patients (3/93, 3%) showed clinical progression and required surgery. Another 19 patients (19/93, 20%) decided to transition to surgical intervention even though there was no evidence of disease progression. All operated patients had excellent response to initial treatment despite the delayed surgery.

Conclusions: Within an Italian medical context, active surveillance appears to be a feasible and safe alternative to immediate surgery in healthy mPTC patients. Only 3% of mPTC demonstrated disease progression during a median follow-up of 19 months (range 6-54) and importantly demonstrated excellent outcomes after surgical intervention in a short-term follow-up.

Keywords: active surveillance; differentiated thyroid cancer; management; microcarcinoma; observation; outcome.

Figure 1.

Waterfall graph showing the story of each patient enrolled in the study. The different colors distinguish patients who continued active surveillance program (green bars), from those with a disease progression (red bars) and patients who opted for thyroid surgery despite the clinical stability (blue bars). The length of the bars represents the duration of follow-up.