ETA2022 Poster Presentations Thyroid Cancer CLINICAL 1 (10 abstracts)
1Unit of Endocrinology, Department of Clinical and Experimental Medicine, Pisa, Italy; 2Department of Clinical and Experimental Medicine, Unit of Endocrinology, University Hospital of Pisa; 3University of Pisa, Endocrine Unit, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Pisa, Italy, Unit of Endocrinology, Pisa, Italy; 4Nuclear Medicine Unit, Azienda Ospedaliero-Unuversitaria Pisana, University Hospital of Pisa, Pisa 56124, Italy; 5Department of Surgical, Medical and Molecular Pathology, University Hospital of Pisa, Via Paradisa 2, 56124 Pisa, Italy; 6University of Pisa, Endocrinology Unit, Department of Endocrinology, Pisa, Italy; 7Oncology Section of the Endocrine Unit, Dept of Clin and Exp Medicine, University Pisa, Pisa, Italy
Objectives: Currently 131I treatment after surgery is suggested in selected intermediate-risk and in high-risk patients with DTC. In patients with radio-avid structural disease and in those with biochemical disease a second 131I treatment could be considered. However data about the impact of the second 131I treatment on clinical status remains controversial.
Methods: Clinical data of 231 DTC patients followed at the Unit of Endocrinology of the University Hospital of Pisa, who experienced the second 131I treatment for indeterminate/biochemical (BiR) or structural incomplete response (StR), were collected.
Results: Most of patients were females (64.9%). Median age was 41 and median tumor size was 2.1 cm. Most of cases were pT1 according to TNM 8th edition (45.5%) and pN1 disease accounted for 51.5% of the cases. CV-PTC was the most frequent histology (59.3%). Multifocality and bilaterality were frequently observed (77.7%), like mETE (70%); while in 32.4% of the cases vascular invasion was diagnosed. All patients were submitted to the first 131I treatment either with low (61%) or high (39%) 131I activities. Eight patients (3.5%) performed neck surgery for lymph node metastases before second 131I treatment and, for this reason, were excluded from the study. Therefore 223 patients performed a second 131I treatment: 65.5% (n = 146) because of BiR and 34.5% (n = 77) because of StR, either for radio-avid disease or for positive neck ultrasound Regarding BiR patients (n = 146) the second 131I treatment led to excellent response (ExR) in 13.7%, while BiR persisted in 64.4%. In the remaining 32 patients (21.9%) a StR was detected, either because radio-avid (40.4%) or for the identification of lymph node metastases by neck ultrasound (59.4%). Conversely in patients who performed the second 131I treatment for an initial StR (n = 77), 6.5% showed an ExR, 15.6% a BiR and 77.9% a persistent StR. During the follow-up, overall, 58.3% (n = 130) experienced further treatments, while 41.7% (n = 93) were followed-up without any other treatment. After a median follow-up of 9.6 years, ExR accounted for 22.9%, BiR for 48.8% and StR for 28.7% of all study group.
Conclusions: Only 11.2% of patients can be cured by a second 131I treatment. Other treatments, any type, performed in about 60% of patients, increased the percentage of cured patients up to 23%, during a follow-up of about 10 years.