. 2021 May 17;52(3):823–832. doi: 10.1007/s12029-021-00646-6

Table 3.

Main recommendations from TC guidelines pertaining the LRTs for LMs from TC

Guideline	Disease	Recommendations
ATA 2015 [10]	DTC	Thermal ablation (RFA and cryoablation) may be considered as valid alternatives to surgery Thermal ablation should be considered prior to initiation of systemic treatment when the individual distant metastases are symptomatic or at high risk of local complications
ETA 2019 [30]	Radioiodine-refractory DTC	LRTs should be considered either alongside systemic therapies or alone in case of progression of a single lesion or multiple lesions in a single organ, with the aim of controlling symptoms, optimize disease control or delay the initiation of systemic treatments and their toxicities. When employed during systemic therapy, TKIs could be continued or interrupted temporarily for few days TACE can be applied to LMs from advanced TC, particularly when LMs are smaller than 30 mm and liver involvement is < 30%, although benefits in prolonging survival or delaying progression are yet unproven RFA can be applied to single, unresectable lesions or, in alternative, as a debulking procedure before surgical resection
ATA 2015 [31]	MTC	Treatment is indicated in patients with LMs that are large, increasing in size, or associated with symptoms such as diarrhoea or pain TACE should be considered in patients with disseminated tumors < 30 mm in size involving less than a third of the liver
ESMO 2019 [32]	DTC, MTC	If true solitary lesions are detected, they may be candidates for local ablation In MTC patients with a dominant lesion that is growing more rapidly than the background disease, local ablation (e.g. RFA) may be useful for controlling symptoms, such as diarrhea If both surgery and RFA are contraindicated, TACE might be an option

Guideline

Disease

Recommendations

ATA

2015 [10]

DTC

Thermal ablation (RFA and cryoablation) may be considered as valid alternatives to surgery

Thermal ablation should be considered prior to initiation of systemic treatment when the individual distant metastases are symptomatic or at high risk of local complications

ETA

2019 [30]

Radioiodine-refractory DTC

LRTs should be considered either alongside systemic therapies or alone in case of progression of a single lesion or multiple lesions in a single organ, with the aim of controlling symptoms, optimize disease control or delay the initiation of systemic treatments and their toxicities. When employed during systemic therapy, TKIs could be continued or interrupted temporarily for few days

TACE can be applied to LMs from advanced TC, particularly when LMs are smaller than 30 mm and liver involvement is < 30%, although benefits in prolonging survival or delaying progression are yet unproven

RFA can be applied to single, unresectable lesions or, in alternative, as a debulking procedure before surgical resection

ATA

2015 [31]

MTC

Treatment is indicated in patients with LMs that are large, increasing in size, or associated with symptoms such as diarrhoea or pain

TACE should be considered in patients with disseminated tumors < 30 mm in size involving less than a third of the liver

ESMO

2019 [32]

DTC, MTC

If true solitary lesions are detected, they may be candidates for local ablation

In MTC patients with a dominant lesion that is growing more rapidly than the background disease, local ablation (e.g. RFA) may be useful for controlling symptoms, such as diarrhea

If both surgery and RFA are contraindicated, TACE might be an option

DTC differentiated thyroid cancer, LMs liver metastases, LRTs loco-regional treatments, MTC medullary thyroid cancer, RFA radiofrequency ablation, TACE trans-arterial chemoembolization, TKI tyrosine kinase inhibitor