Clinical trial NCT03363347: BRAF V600E and Redifferentiation Therapy in Radioiodine-refractory Papillary Thyroid Cancer
Official title: Association Between BRAF V600E and Redifferentiation Therapy in Patients With Radioiodine-refractory Papillary Thyroid Cancer
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Thyroid Cancer
Lead sponsor: Heidelberg University
Sponsor class: OTHER
First posted: 2017-12-06
Enrollment: 25
Sex: ALL
Minimum age (years): 24
Maximum age (years): 69
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: RETROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Twelve patients with radioiodine-refractory papillary thyroid cancer were treated with retinoic acid before a further course of radioiodine therapy. One patient had to be excluded from the analysis due to missing data in this retrospective analysis. Furthermore, they were compared with twelve patients with radioiodine-sensitive thyroid cancer who were considered as cured after a maximum of two radioiodine therapies.

Brief summary: Papillary thyroid cancer (PTC) is the most common neoplasia in the thyroid gland. The combination of surgery, followed by radioiodine therapy (RIT) and thyroid-stimulating hormone (TSH) suppressive therapy is usually a curative option for differentiated thyroid cancer (DTC). Although DTC has a good prognosis generally, it is problematic when dedifferentiation is suspected and radioiodine refractoriness presumed. One possible therapy option for redifferentiation is the pretreatment with retinoids. From 2008 to 2014 there were 13 patients with PTC who were treated with retinoids after thyroidectomy before a further course of radioiodine. A recent study has shown that the efficacy of Selumetinib, another option for redifferentiation depends on the mutational status of the treated patient. In this retrospective study the investigators looked for a similar association between BRAF V600E and redifferentiation therapy with retinoids. As retinoids have fewer side effects compared to TKI, it is worth performing studies to assess the importance of genetic marker for the response and to estimate the chances of this specific patient collective. BRAF V600E seems to be associated with better long-term response after redifferentiation therapy with 13-cis RA in RAI-R PTC. Therefore, evaluation of BRAF mutational status prior to redifferentiation therapy could be beneficial for predicting response.


Eligibility criteria: Eligible criteria for radioiodine-refractory patients included:

* PTC
* no response to former RIT
* decrease or loss of initial sufficient RI-Uptake
* redifferentiation therapy with 13-cis-RA
* available FFPE tissue.

Eligible criteria for radioiodine-sensitive patients included:

* PTC
* cured after a maximum of two RIT
* no redifferentiation therapy necessary
* available FFPE tissue.

Exclusion criteria

* DTC other than PTC
* patients lost to follow-up
* other redifferentiation therapy than retinoids
* anaplastic or medullary thyroid cancer
* benign thyroid disease, no available FFPE tissue
* more than two RITs in the control group
* insufficient clinical information.

Primary outcomes:
measure: Response to radioiodine therapy after redifferentiation
timeFrame: 7 years
Secondary outcomes:
measure: Parameter tumor size
timeFrame: 7 years
measure: Parameter thyroglobulin levels (serum Tg)
timeFrame: 7 years
measure: Parameter radioiodine-uptake (RI-Uptake)
timeFrame: 7 years
Other outcomes:
Locations:
Study officials:
affiliation: Head of the Clinical Study Center for Diabetes Research
name: Stefan Kopf, MD
role: PRINCIPAL_INVESTIGATOR
References: