High-Dose RAI Therapy Justified by Pathological N1a Disease Revealed by Prophylactic Central Neck Dissection for cN0 Papillary Thyroid Cancer Patients: Is it Superior to Low-Dose RAI Therapy?
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One of the presumed advantages of prophylactic central neck dissection (pCND) is offering staging basis for more aggressive radioactive iodine (RAI) therapy, which postulates the necessity of high dose for treatment efficacy. The present study aims to compare the effectiveness between low-dose and high-dose RAI in a select cohort of cN0 papillary thyroid cancer (PTC) patients with pathological N1a (pN1a) disease revealed by pCND in terms of ablation rate and response to therapy. The frequency of short-term adverse effects between the two groups was also compared.
Patients and Methods
From January 2014 to April 2016, cN0 PTC patients with pN1a disease revealed by pCND in our hospital were retrospectively reviewed. Patients with other indications for high-dose RAI, such as the presence of extrathyroidal extension, vascular invasion or suspicions of distant metastasis, were excluded. For the included patients, high dose (3700 MBq) was administered between January 2014 and August 2015 and low dose (1110 MBq) between August 2015 and April 2016. Ablation assessment was performed 6 months after RAI therapy. Response evaluation after RAI therapy was performed after 46.3 ± 9.5 months for high-dose group and 29.1 ± 2.6 months for low-dose group. All patients were also evaluated for short-term adverse effects 24 and 72 hours after RAI administration.
A total of 84 patients were enrolled. Among them, 42 were in the high-dose group and the other 42 in the low-dose group. There was no significant difference in ablation rate (P = 0.7707) and response to RAI therapy (P = 0.6454) between the two groups. Twenty-four hours after RAI administration, neck pain and swelling (33.3% VS. 11.9%; P = 0.0372) and gastrointestinal discomfort (45.2% vs. 21.4%; P = 0.0373) were significantly more frequent in the high-dose group.
High-dose RAI therapy, with higher frequency of short-term adverse effects, appears to be not superior to low-dose RAI therapy for cN0 PTC patients with pN1a disease revealed by pCND to achieve better response to therapy. Further randomized studies with larger series of patients and longer follow-up duration, especially with the low-dose group, are needed to validate our results.
This work was supported by the Young Researcher Fund of Science and Technology Department of Jilin Province (Grant number: 20170520027JH) and the Norman Bethune Youth Program of Jilin University (Grant number: 2015219).
Compliance with ethical standards
Conflict of interest
The author declares that they have no conflict of interest.
- 2.Randolph GW, Duh QY, Heller KS et al (2012) The prognostic significance of nodal metastases from papillary thyroid carcinoma can be stratified based on the size and number of metastatic lymph nodes, as well as the presence of extranodal extension. Thyroid. 22(11):1144–1152. https://doi.org/10.1089/thy.2012.0043 CrossRefPubMedGoogle Scholar
- 7.Lin B, Qiang W, Wenqi Z, Tianyu Y, Lina Z, Bin J (2017) Clinical response to radioactive iodine therapy for prophylactic central neck dissection is not superior to total thyroidectomy alone in cN0 patients with papillary thyroid cancer. Nucl Med Commun. 38(12):1036–1040. https://doi.org/10.1097/mnm.0000000000000756 CrossRefPubMedGoogle Scholar
- 8.Haugen BR, Alexander EK, Bible KC et al (2016) 2015 American Thyroid Association Management Guidelines for adult patients with thyroid nodules and differentiated thyroid cancer: the American thyroid association Guidelines task force on thyroid nodules and differentiated thyroid cancer. Thyroid. 26(1):1–133. https://doi.org/10.1089/thy.2015.0020 CrossRefPubMedGoogle Scholar
- 13.Castagna MG, Cevenini G, Theodoropoulou A et al (2013) Post-surgical thyroid ablation with low or high radioiodine activities results in similar outcomes in intermediate risk differentiated thyroid cancer patients. Eur J Endocrinol. 169(1):23–29. https://doi.org/10.1530/eje-12-0954 CrossRefPubMedGoogle Scholar
- 21.Leboulleux S, Rubino C, Baudin E et al (2005) Prognostic factors for persistent or recurrent disease of papillary thyroid carcinoma with neck lymph node metastases and/or tumor extension beyond the thyroid capsule at initial diagnosis. J Clin Endocrinol Metab. 90(10):5723–5729. https://doi.org/10.1210/jc.2005-0285 CrossRefPubMedGoogle Scholar
- 22.Ryu IS, Song CI, Choi SH, Roh JL, Nam SY, Kim SY (2014) Lymph node ratio of the central compartment is a significant predictor for locoregional recurrence after prophylactic central neck dissection in patients with thyroid papillary carcinoma. Ann Surg Oncol. 21(1):277–283. https://doi.org/10.1245/s10434-013-3258-1 CrossRefPubMedGoogle Scholar
- 23.Zheng CM, Ji YB, Song CM, Ge MH, Tae K (2018) Number of Metastatic Lymph Nodes and Ratio of Metastatic Lymph Nodes to Total Number of Retrieved Lymph Nodes Are Risk Factors for Recurrence in Patients With Clinically Node Negative Papillary Thyroid Carcinoma. Clin Exp Otorhinolaryngol. 11(1):58–64. https://doi.org/10.21053/ceo.2017.00472 CrossRefPubMedGoogle Scholar