ECE2023 Rapid Communications Rapid Communications 6: Endocrine-related Cancer (6 abstracts)
Introduction: An increase in the incidence of differentiated thyroid cancer (DTC) has been observed in recent decades. Despite the excellent prognosis, DTC patients remain on lifelong oncologic follow-up after treatment, due to fear of recurrence.
Aim: Was to evaluate the frequency of real recurrence, defined as appearance of structural or biochemical disease after >12 month period of no evidence of disease (NED) in DTC patients.
Material and methods: A retrospective analysis of medical records of 3087 consecutive DTC patients (after the operation alone or operation and 131-I therapy) being under observation from 1998 to 2021. Clinicopathological features including histology, tumor size, extrathyroidal extension, angioinvasion, multifocality, resection margin involvement, lymph node (LN) and distant metastases, were obtained from all the patients. Moreover, the stage of the disease was assessed or reassessed according to TNM 8th edition of UICC and response to therapy according to the ATA recommendation, in all the patients. Only patients with an excellent response were submitted to further analysis. The percentage of recurrence and cumulative recurrence rate (CRR) were analyzed.
Results: Females accounted for 85.4% of the patients. Papillary TC was the most common in 2827 patients (91.6%). Median age was 52 years (range: 13-86 years). Median tumour size- 9 mm (range 0-144 mm). 15% of the patients had LN and 2.7% distant metastases. Excellent response to therapy was observed in 2302 patients (74.6%)- among them true recurrence developed in 34 patients (1.5%). The recurrence was significantly more common in patients with: other than PTC type of TC (P=0.009), larger tumour size (P<0.0001), angioinvasion (P=0.0015) and lymph node metastases (P=0.0063), TNM stage (P=0.0013) and treated with 131-I (P=0.0045). In the univariate analysis, histological type-PDTC (HR: 9.581 CI:2.278-40.293 P=0.002), tumour size 11-40 mm (HR:2.703 CI:1.291-5.662 P=0.008) and >40 mm (HR: 6.879 CI:2.423-19.533 P<0.001), LN metastases (HR: 3,861 CI:1.752-8.511 P<0,001), angioinvasion (HR: 4.836 CI: 1.186 10.698 P<0.001), stage II TNM (HR: 5.4945 CI:2.389 12.636 P<0.001) were associated with a risk of recurrence. Higher CRR was observed in poorly differentiated and oncocytic TC, than in FTC and PTC.
Conclusion: 1. Real recurrence is rare in patients with DTC- it accounts for 1,5%.2. Despite of excellent response to the therapy, patients with advanced stage of disease have higher risk of recurrence.
13 May 2023 - 16 May 2023