Local ablative therapy of oligoprogressive TKI-treated thyroid cancer

Tailored management of advanced thyroid cancer patients treated with lenvatinib or vandetanib: the role of a multimodal approach

BACKGROUND

In differentiated/poorly differentiated (DTC/PDTC) or medullary thyroid cancer (MTC) treated with kinase inhibitors (KIs), additional treatments (ATs) can be performed in selected cases.

METHODS

We retrospectively analysed all the ATs performed in our center in KI-treated TC patients, evaluating the subsequent KI modulation, the local PD in case of loco-regional procedure (LRP) and the AT-related complications. DTC/PDTC patients with or without progressive disease before the first AT (PD and NO PD GROUP, respectively) were analysed separately.

RESULTS

In our center, 32 ATs (30 LRPs and 2 radioactive iodine treatments) were performed in 14 DTC/PDTC patients and 4 MTC subjects after the start of systemic therapy with lenvatinib or vandetanib (27 and 5 ATs, respectively). Brain was the most treated site (11/30 LRPs) and external beam radiation was the most employed LRP (18/30 LRPs). KIs dose reduction or discontinuation of KI therapy (at least transient) was performed after 50% of ATs in DTC/PDTC NO PD GROUP. The KI was maintained at the same dosage after 75% and 50% of the ATs performed in DTC/PDTC PD GROUP and MTC, respectively. During the follow-up, local PD was detected after 14 LRPs. Local progression-free survival (LPFS) was significantly shorter in DTC/PDTC PD GROUP in comparison to NO PD GROUP (12 month-LPFS 91.7% versus 15.2%); in patients with MTC, 12 month-LPFS was 50%. AT-related AEs were mostly G1-G2.

CONCLUSIONS

In selected DTC/PDTC without previous PD and treated with a multimodal strategy, local disease control is generally maintained regardless the KI dose modulation. In DTC/PDTC patients with previous limited PD and in MTC subjects, the choice of performing a LRP and continue the ongoing KI therapy must consider the risk of early local progression. AT-related AEs in KI treated patients were mild in most cases.

Radio-iodine refractory thyroid cancer patients: a tailored follow-up based on clinicopathological features

OBJECTIVE

To report the experience of a single center for the selection of radioiodine-refractory (RAIR) thyroid cancer patients (RAIR-TC) who needed tyrosine kinase inhibitor (TKIs) treatment.

PATIENTS AND METHODS

We evaluated all features of 279 RAIR-TC patients both at the time of diagnosis and at the RAIR diagnosis.

RESULTS

Ninety-nine patients received indication to TKIs (Group A), while 180 remained under active surveillance (Group B). Group A had greater tumor size, more aggressive histotype, more frequent macroscopic extrathyroidal extension, distant metastases, advanced AJCC stage, and higher ATA risk of recurrence. After RAIR diagnosis, 93.9% of Group A had progression of disease (PD) after which TKIs' therapy was started. The remaining 6.1% of patients had a so severe disease at the time of RAIR diagnosis that TKIs' therapy was immediately started. Among Group B, 42.7% had up to 5 PD, but the majority underwent local treatments. The mean time from RAIR diagnosis to the first PD was shorter in Group A, and the evidence of PD within 25 months from RAIR diagnosis was associated with the decision to start TKIs.

CONCLUSIONS

According to our results, a more tailored follow-up should be applied to RAIR-TC patients. A too strict monitoring and too many imaging evaluations might be avoided in those with less-aggressive features and low rate of progression. Conversely, RAIR-TC with an advanced stage at diagnosis and a first PD occurring within 25 months from RAIR diagnosis would require a more stringent follow-up to avoid a late start of TKIs.

Long-term management of lenvatinib-treated thyroid cancer patients: a real-life experience at a single institution

PURPOSE

The efficacy of lenvatinib for advanced and progressive radioactive iodine refractory differentiated thyroid cancer is well established. Herein, we retrospectively evaluated the long-term safety and efficacy of lenvatinib in 23 patients treated at a single Institution.

METHODS

Clinical data of all patients treated for a differentiated thyroid cancer with lenvatinib from April 2015 to September 2020 were retrospectively analyzed.

RESULTS

A total of 23 patients were included. In all, 21 patients received lenvatinib as first-line systemic therapy. Median age at initiation of lenvatinib treatment was 68 (44-90) years. Median duration of the study from initiation of lenvatinib to study end was 23 (2-65) months. The indication for lenvatinib treatment was documented progression of distant metastases in 20 patients and of locally advanced disease in the other 3 and median duration of lenvatinib therapy was 15 (2-64) months. Best treatment responses were: partial response in 6 patients, stable disease in 14, progressive disease in 1, and not evaluable in 2. Median progression-free survival was 25 months (95% CI: 12-40) and median overall survival was 46 months (95% CI: 28-65). Three patients had to discontinue lenvatinib treatment due to serious adverse events and no drug-related death was observed. Ten patients continued lenvatinib for more than 24 months and the only newly registered adverse event after this period of time was one case of G2 proteinuria. Six patients continued lenvatinib treatment beyond documented tumor progression due to oligoprogression or slowly progressive disease (median time 18.5 months, 8-42 months). A total of 14 patients were alive at the end of the study: 11 showed partial response/stable disease on lenvatinib, including 3 who had a stable disease after local ablative therapy for oligoprogressive metastases; 3 had to change treatment, including 2 for lenvatinib-related serious adverse events and 1 for progressive disease.

CONCLUSIONS

Long-term lenvatinib treatment is safe and some patients may experience persistent long-term control of the disease. Late treatment-related AEs rarely occurred. Oligoprogressive and slowly progressive disease can be managed without treatment withdrawal as long as there are some clinical benefits.

Stereotactic radiotherapy for oligoprogressive ER-positive breast cancer (AVATAR)

BACKGROUND

The enhanced knowledge of cancer biology has led to considerable advancement in systemic therapy for advanced breast cancer. Recently, studies showed that cyclin-dependent kinase (CDK) 4/6 inhibitor, when added to endocrine therapy, had improved the outcomes of patients with advanced ER-positive HER2-negative breast cancer. However, the disease often progresses following a period of treatment response. In a subset of patients, disease progression may occur at limited sites, i.e., oligoprogressive disease (OPD). In the past few years, stereotactic radiotherapy (SRT) has emerged as a safe and effective treatment for advanced cancer when delivered to limited metastatic sites. Hence, it is worth investigating the role of SRT in the setting of oligoprogressive breast cancer.

METHOD

AVATAR is a multicentre phase II registry trial of SRT with endocrine therapy and CDK 4/6 inhibitor for the management of advanced ER-positive HER2-negative breast cancer. The study aims to enrol 32 patients with OPD limited to 5 lesions. The primary endpoint of the study is time to change systemic therapy measured from the commencement of SRT to change in systemic therapy. Secondary objectives include overall survival, progression free survival and treatment related toxicity. The exploratory objective is to describe the time to change in systemic therapy by the site (bone only vs. non-bone lesions) and number (1 vs. > 1) of OPD.

DISCUSSION

This study aims to explore the effect of SRT in maximising the benefit of systemic therapy in patients with oligoprogressive ER-positive HER2-negative breast cancer. This approach might help reduce the burden of disease and improve the life quality in these patients.

TRIAL REGISTRATION

ACTRN, ACTRN12620001212943 . Date of registration 16 November 2020- Retrospectively registered.

Management of one patient with oligoprogressive thyroid cancer during treatment with lenvatinib

Recent thyroid cancer guidelines found it reasonable to use local therapies during treatment with tyrosine kinase inhibitors (TKIs) in selected patients with oligoprogressive disease, namely, in the presence of a single progressing lesion in an otherwise TKI-responsive metastatic cancer. However, there is a lack of experience in the management of oligoprogressive thyroid cancers. This report illustrates the case of one patient with oligoprogressive thyroid cancer during therapy with lenvatinib. We found that the application of local ablative therapy in oligoprogressive disease prolonged the progression-free survival and thus extended the time to therapy interruption. However, the optimal care for TKI-treated oligoprogressive cancers remains unclear and needs to be investigated in prospective trials.