Endocrine Abstracts

Introduction: The treatment with tyrosine-kinase inhibitor drugs (1st line Lenvatinib) in patients with radioiodine-refractory differentiated thyroid cancer (I-131) and disease progression can be burdened by important side effects which often require suspension/reduction of the therapy and correct multidisciplinary management.

Patients and methods: Clinical/histopathological characteristics, outcome, adverse events and the role of gender have been evaluated in a consecutive series of 28 patients with Radioactive iodine-refractory differentiated thyroid cancer and progressive disease (RECIST criteria) treated with Lenvatinib.

Results: Clinical/histopathological characteristics, clinical outcome and adverse events are shown in Table 1. The male/female ratio (1.5/1) showed an higher frequency of aggressive tumors in males. Most patients fell into stage II and about 25% had loco-regional and distant metastases at diagnosis. Almost all patients (93%) were treated with I-131. Radioactive iodine-refractory from diagnosis were of 3.8 years. Approximately 90% of patients experienced adverse events, mostly gastrointestinal disorders and hypertension. Analyzing them by gender, the only statistically significant difference was on gastrointestinal symptoms (0.02). Moreover other not significant differences probably depend on the low sample number. At last visit, 75% of the patients showed stable disease and 25% progressive disease.

Conclusions: Most of the side effects occur in the first weeks of therapy, however, periodic and early reassessment of any side effects is necessary to minimize the reduction and/or suspension of therapy.