Real-world treatment patterns and clinical outcomes in patients with radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) treated with first line lenvatinib monotherapy in the United States

PURPOSE

Lenvatinib was approved for the treatment of patients with radioiodine-refractory differentiated thyroid cancer (RAI-R DTC) in the United States (US) in 2015. The main objective of the current study was to assess real-world clinical effectiveness in RAI-R DTC patients treated with first line lenvatinib monotherapy in the US.

METHODS

A retrospective chart review was conducted in RAI-R DTC patients who initiated lenvatinib monotherapy as first line treatment between February 2015 and September 2020. Anonymized data were abstracted by prescribing physicians from individual patient's electronic health records. Clinical outcomes included provider-reported real-world best overall response (rwBOR), real-world progression-free survival (rwPFS), and overall survival (OS). Time-to-event endpoints were assessed using Kaplan-Meier methods.

RESULTS

Our study included 308 RAI-R DTC patients treated with first line lenvatinib. At lenvatinib initiation, patients' median age was 60 years, 51.6% were female, and 26.0% of patients had an ECOG performance score of ≥2. Over the follow-up period, 32.5% of patients discontinued first line lenvatinib permanently, with others remaining on treatment. The median duration of lenvatinib therapy was 17.5 months overall. Provider-reported rwBOR (complete or partial response) to lenvatinib was 72.4%. Median rwPFS was 49.0 months. Estimated rwPFS rates at 24 and 48 months were 68.5% and 55.0%, respectively. Estimated OS rates at 24 and 72 months were 78.4% and 57.0%, respectively; median OS was not reached.

CONCLUSION

The current study reinforces the clinical effectiveness of first line lenvatinib as standard of care in patients with RAI-R DTC in real-world clinical practice in the US.

Relationship between clinicopathologic factors and FDG avidity in radioiodine-negative recurrent or metastatic differentiated thyroid carcinoma

BACKGROUND

In this study, we investigated the relationship between clinicopathologic factors, BRAFV600E mutation status and [18F] F-fluoro-2-deoxyglucose (FDG) avidity in patients with radioiodine (RAI)-negative recurrent or metastatic differentiated thyroid cancer (DTC).

METHODS

From 2015 to 2018 all patients with suspected recurrent or metastatic radioiodine-negative DTC patients who underwent FDG positron emission tomography/computed tomography (PET/CT) were retrospectively reviewed. Suspected lesions on FDG PET/CT were biopsied and underwent BRAFV600E mutation testing by immunohistochemistry and real-time PCR. Tumor size, recurrent versus metastatic disease, histopathologic features including classical type versus aggressive subtypes (poorly differentiated, tall cell, columnar cell, hobnail variants) and BRAFV600E mutation status were correlated with the SUVmax of highest hypermetabolic lesions on FDG PET/CT by the univariate analysis using logistic regression.

RESULTS

Sixty-three consecutive patients, 55 (87.3%) female, with median age of 48 (range 17-81) were included. The majority of patients had BRAFV600E mutation and classical subtype, 55/63 (87.3%) and 45/63(71.4%), respectively. Thyroglobulin at the time of suspected recurrence was 262.7 ng/ml (range 16.3-1000) and patients received a median 3 prior RAI treatments. Fifty-four patients (85.7%) had local recurrence. The majority of patients 58/63 (92.1%) had FDG-avid disease on PET/CT. On univariate analysis, tumor size aggressive histopathologic types and distant metastasis are the significant factors for predicting FDG uptake, p = 0.04, p = 0.001 and p = 0.004 respectively. Although FDG uptake of BRAFV600E bearing recurrent/metastatic RAIR DTC lesions was higher than those without the mutation, the difference did not reach statistical significance, SUVmax of 7.11 versus 4.91, respectively, p = 0.2.

CONCLUSION

The majority of recurrent or metastatic RAI-negative DTC have BRAFV600E mutation and detectable disease on FDG PET/CT. FDG avidity of the recurrent or metastatic RAI-negative DTC is independently associated with the aggressive histopathologic features.

[New aspects in thyroid cancer treatment : Highlights of the ASCO Annual Meeting 2018]

Whereas surgical treatment of thyroid carcinoma plays an important role especially in the early stages, a multimodal approach is pursued in the palliative setting, which, in addition to classical chemotherapy primarily involves treatment with tyrosine kinase inhibitors. An analysis of clinical trials and studies presented at the American Society of Clinical Oncology (ASCO) Annual Meeting 2018 is presented. In particular, studies on the treatment of radioiodine-refractory differentiated thyroid cancer, anaplastic thyroid cancer and immunotherapy were selected and analyzed. Clinically and preclinically relevant studies are presented and critically interpreted in this review.

Differential expression profiling of circulation microRNAs in PTC patients with non-131I and 131I-avid lungs metastases: a pilot study

INTRODUCTION

Loss of the ability to concentrate (131)I is one of the important causes of radioiodine-refractory disease in papillary thyroid carcinoma (PTC). Recent advantages of serum microRNAs (miRNAs) open a new realm of possibilities for noninvasive diagnosis and prognosis of many cancers. The aim of the current study was to identify differential expression profiling of circulation miRNAs in PTC patients with non-(131)I and (131)I-avid lungs metastases.

METHODS

The expressions of miRNAs were examined using miRNA microarray chip. The most significantly changed miRNAs from microarray were verified by using qRT-PCR. The potential miRNAs regulating target genes and their preliminary biological functions were forecasted by Bioinformatic analysis.

RESULTS

Compared to (131)I-avid lung metastases, 13 kinds of significantly differential serum miRNAs including 5 upregulated miRNAs (miR-1249, miR-106a, miR-503, miR-34c-5p, miR-1281) and 8 downregulated miRNAs (miR-1915, miR-2861, miR-3196, miR-500, miR-572, miR-33b, miR-554, miR-18a) in PTC patients with non-(131) I-avid lung metastases were identified. Bioinformatic analysis demonstrated that miR-106a was the core miRNA regulating 193 genes in the network. The results of validation confirmed the up-regulation of miR-106a in non-(131)I-avid lungs metastatic PTC patients.

CONCLUSION

Differentially expressed serum miRNA profiles between PTC patients with non-(131)I and (131)I-avid lungs metastases were analyzed. These findings in our present study could represent new clues for the diagnostic and therapeutic strategy in PTC patients with non-(131)I-avid metastatic disease.

Alternative medical treatment for radioiodine-refractory thyroid cancers

Thyroid cancer is one of the most rapidly increasing cancers in many countries. Although most thyroid cancers are differentiated cancers and easily treated with radioiodine (RI), a portion of differentiated and undifferentiated cancers is refractory not only to RI therapy, but also to radiotherapy and chemotherapy. Thus, various alternative therapies have been tested in RI-refractory thyroid cancers. These alternative therapies include two major categories: redifferentiation therapy and recent molecular target therapy. Several clinical trials have investigated these therapies. They demonstrated potential effects of the therapies, although the results have been somewhat limited so far. Thus, the future strategy for undifferentiated thyroid cancers will involve individualized, lesion-specific, and combined therapy. In this review, the basic mechanism of each redifferentiation and molecular target therapy is discussed, and results of recent clinical trials using these therapeutic agents are summarized.