Redifferentiation of a BRAF-K601E mutated poorly differentiated thyroid cancer patient with dabrafenib and trametinib treatment.

Redifferentiation of a BRAF-K601E mutated poorly differentiated thyroid cancer patient with dabrafenib and trametinib treatment. Thyroid. 2019 Mar 18;: Authors: Leboulleux S, Dupuy C, Lacroix L, Attard M, Grimaldi S, Corre R, Ricard M, Nasr S, Berdelou A, Hadoux J, Hartl D, Terroir M, Baudin E, Schlumberger M, Al Ghuzlan A Abstract A 59 years old woman with locally invasive poorly differentiated thyroid cancer with synchronous lung, mediastinal and bone metastases and a BRAF-K601E somatic mutation with contra-indication for antiangiogneic drugs was treated with dabrafenib and trametinib. During treatment, serum levels of thyroglobulin increased as soon as day 7 up to 10 folds over baseline at week 4. Concurrently, clinical hyperthyroidism occurred, with free T3 and free T4 levels increasing to 6.6 and 4.4 times its upper normal limit. 18FDG PET/CT at one and two months after treatment initiation showed a PERCIST metabolic response with a 82% decrease in 18FDG uptake whereas disease remained morphologically stable according to RECIST criteria. The diagnostic radioactive iodine whole body scan performed when the patient was thyrotoxic with an undetectable serum TSH level, in the absence of any exogenous TSH stimulation, showed high RAI uptake in the lung, mediastinum and skull metastases. The biopsy performed 2 months after treatment initiation showed a more differentiated growth pattern and a decrease in the mitotic activity as compar...
Source: Thyroid : official journal of the American Thyroid Association - Category: Endocrinology Tags: Thyroid Source Type: research