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1 Departments of General and Endocrine Surgery and
2 Emergency Medicine, Medical University of Lodz, 93-338 Lodz, Poland
3 Copernicus Diagnostic Center, Copernicus Hospital, Lodz, Poland
4 Department of Endocrinology and Metabolic Diseases, Medical University of Lodz, Lodz, Poland
(Correspondence should be addressed to M Dedecjus; Email: mdedecjus{at}wp.pl)
| Abstract |
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| Introduction |
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Despite the good results, obtained in embolizations in the head, neck and CNS tumours, the number of publications, considering the application of selective embolization of thyroid arteries (SETA) in the treatment of thyroid diseases, is limited. In Xiao et al.(2002), their work proposed arterial embolization as a novel approach to thyroid ablative therapy. The authors performed selective arteriography, using Seldinger (1953) technique, followed by embolization of thyroid arteries in 22 patients with Graves disease. From that group of the patients, 14 remained euthyroid after SETA, 6 were operated on because of goitres and 2 needed a maintenance dose of anti-thyroid therapy. The investigators did not note any serious complications in any of those patients. After almost 2-year follow-up, they stated this procedure to be effective, minimally invasive and safe. On the other hand, there are some reports on the effective use of SETA in the treatment of vascular lesions of the thyroid arteries (Perona et al. 1999, Jeganath et al. 2001, Kos et al. 2001, Garrett et al. 2005). Also numerous studies have been performed on embolization of the skeletal metastases from the differentiated thyroid cancer (DTCs; Court et al. 2000, Smit et al. 2000, van Tol et al. 2000, Eustatia-Rutten et al. 2003, Lorenz et al. 2005). The number of studies on SETA application in primary thyroid cancer is limited and they are based on small number of patients (Beers et al. 1985, Ramos et al. 2004, Tazbir et al. 2005).
Since the application of SETA may be regarded as an alternative and/or an addition to the existing treatment of selected cases of thyroid cancer in the present study, the usefulness of SETA was evaluated as a pretreatment to thyroid surgery in selected cases of DTC. It was also analysed as a palliative therapy in selected cases of advanced inoperable anaplastic thyroid carcinoma (ATC).
| Patients and methods |
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| SETA |
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| Determination of concentrations of free triiodothyronine (FT3), thyroxine (FT4), thyrotropin (TSH), thyroglobulin (Tg), parathormone (PTH) and calcium (Ca++) |
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Imaging diagnostics
All the patients were diagnosed by ultrasound examination ultrasound Doppler imaging and fine needle aspiration biopsy. The examinations were performed before SETA as a routine procedure, and after SETA, in order to estimate its effect on thyroid vascularization and morphology. Before SETA, angio-16 W CT scan with 3D reconstruction was performed in all the cases. The patients with important stenosis (>70%) of internal carotid arteries were disqualified from SETA, except for ATC patients with bleeding from the tumour. In order to estimate the effectiveness of SETA and changes in the thyroid after embolization in selected cases, angio-16 W CT scan with 3D reconstruction was performed 1–6 days after SETA. All the patients had thyroid angiography just before SETA (to estimate the vascularization status of the organ and choose the right diameter of PVA granules) and immediately after embolization (to estimate the effect of SETA and ensure the closure of targeted arteries).
Statistical analyses
Paired t-test was used to evaluate differences in the concentrations of biochemical parameters (with normal distribution) in patients before and after SETA. For comparison of Tg concentration, the non-parametric Mann–Whitney U test was used. Unpaired t-test was used to assess whether there was any difference in operating time and blood loss between the patients, thyroidectomized because of DTC after preresective embolization and thyroid volume-matched patients, and thyroidectomized because of DTC without preresective embolization. Coefficients of correlation, r and P, were calculated using linear regression analysis and Spearmans rank correlation analysis as appropriate. The level of statistical significance was set at P<0.05. Unless otherwise stated, the values are expressed as the means ± S.D.
| Results |
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In all the patients, SETA effectively limited blood flow through the thyroid arteries confirmed immediately after embolization by angiography and, later, by CT scan and/or ultrasound examination. We did not observe any changes in thyroid volume, either before or after embolization (90.4 ± 26.4 ml versus 88.9 ± 24.9 ml). We noted a massive increase in serum Tg concentration after SETA (130.9 ± 48.89 vs 15 441.26 ± 41 895.9 respectively; P<0.003, Table 3
), which was related to the time period between embolization and thyroidectomy (r = 0.69, P<0.001). Together with Tg increase, we observed an increase of free thyroid hormone concentrations (FT4 15.01 ± 3.1 vs 20.15 ± 4.55 respectively, P = 0.052 and FT3 4.79 ± 0.88 vs 6.1 ± 8.5 respectively, P<0.008) and a consequent decrease of TSH concentrations (2.96 ± 1.3 vs 1.6 ± 1.47 respectively, P<0.006, Table 3
). In all the patients, calcium and PTH concentrations were within the normal range before and after embolization, although slight fluctuations were observed (Table 3
).
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SETA in anaplastic thyroid cancer
Palliative SETA in cases of inoperable ATC effectively limited blood flow through the gland. The patients reported improvement in breathing (six patients), swallowing (two patients) and pain decrease (four patients). In two patients after SETA, stridor disappeared and, in other two cases, SETA stopped bleeding from the tumour. Five patients reported improvement of the general condition (Table 2
).
| Discussion |
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The clinical success of embolization is defined as a decrease in the expected blood loss during surgery and/or facilitated tumour removal, and/or reduced surgical complication and/or palliation of the symptoms associated with tumour presence (The American Society of Interventional and Therapeutic Neuroradiology 2001, Lookstein & Guller 2004). The potential advantages of performing SETA before thyroidectomy include shortening of the operative procedure time and increasing the chances of complete surgical resection. Moreover, SETA should allow better visualization of the surgical field with decreased overall surgical complication rate as an effect of limited intraoperative bleeding. The latter point would be of particular importance in thyroid cancer surgery because of the relatively high risk of the damage of surrounding tissue, including parathyroid glands, recurrent laryngeal nerve and oesophagus. While comparing thyroidectomies in advanced DTC, performed after SETA and without preresective embolization, we did not observe any statistical differences, regarding either transient postoperative complications or postoperative definitive sequels. It should be noted that the analysed groups were not randomized and SETA was performed in the cases with the worst prognosis. In the patients with preresective SETA, we observed evident and statistically significant decrease of the operating time and reduced blood loss. Although the operating time and blood loss are of extreme importance, especially in patients with advanced cancer, the differences are, in our opinion, too small to justify routine application of preresective SETA in patients with advanced DTC. However, in favour of preresective SETA, the operating surgeons have reported that preresective embolization facilitated tumour removal. No major or even minor bleeding allowed performing radical manoeuvres which accelerated operation. In some studies, the authors reported reduction of the gland volume after SETA (Xiao et al. 2002, Ramos et al. 2004, Zhao et al. 2007). We compared CT scans of the tumour for 1, 2, 4 and 6 days before and after embolization. There was no difference in thyroid volume, probably, because of the short period between SETA and thyroidectomy. However, we noted structural changes in the gland, which may have been responsible for differences in its consistency, facilitating tumour removal.
Massive increase of Tg concentration and moderate increase of free thyroid hormones are, in our opinion, the effects of ischaemic necrosis of the thyroid gland. Although, SETA limits thyroid blood supply, the veins are not closed and the blood outflow is not limited. In consequence, colloid from dying thyrocytes (comprising Tg, T3 , T4 and, probably, other biochemical compounds) gets into circulation. The review of literature did not help us to elucidate potential consequences of increased serum Tg concentration. However, in the earlier study, the authors described that embolization of DTC metastases caused massive Tg increase, which, probably, resulted in adult respiratory distress syndrome (Elshafie et al. 2000). Considering the above, we suggest performing thyroidectomy up to the 36 h after preresective SETA, as till that time we did not observe any important increase in the concentration of the parameters in question.
In the investigated group, SETA effectively palliated the symptoms related to tumour presence in ATC patients. The patients reported improvement of breathing, swallowing, a decrease of the pain of the neck and improvement of the general condition. However, most of these symptoms are subjective and psychological effect of the therapy cannot be excluded.
The most spectacular effects of SETA included the anti-haemorrhage effect of embolization in case of intractable bleeding from ATC and the disappearance of stridor after tumour embolization. Since the main goal of the palliative therapy is the improved quality of patients life, we believe that SETA, as an effective, minimally invasive and safe method, may become a valuable addition to the therapeutic strategies for inoperable ATC. However, in our opinion, this kind of treatment can only find application in selected cases of advanced thyroid cancer. On the other hand, selective catheterization of thyroid arteries, together with SETA, may potentially become a valuable tool for local chemotherapy, local gene therapy or local immunological therapy of advanced thyroid cancer (Table 3
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| Acknowledgements |
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| References |
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Beers GJ, Svendsen P, Carter AP & Bell R 1985 Embolization of medullary carcinoma of the thyroid invading the trachea, report of a case. Acta Radiologica: Diagnosis 26 21–23.[Web of Science][Medline]
Court C, Noun Z, Gagey O & Nordin JY 2000 Surgical treatment of metastases from thyroid cancer in the axial skeleton. A retrospective study of 18 cases. Acta Orthopaedica Belgica 66 345–352.[Medline]
Elshafie O, Hussein S, Jeans WD & Woodhouse NJ 2000 Massive rise in thyroglobulin with adult respiratory distress syndrome after embolisation of thyroid cancer metastasis. British Journal of Radiology 73 547–549.[Abstract]
Eustatia-Rutten CF, Romijn JA, Guijt MJ, Vielvoye GJ, van den Berg R, Corssmit EP, Pereira AM & Smit JW 2003 Outcome of palliative embolization of bone metastases in differentiated thyroid carcinoma. Journal of Clinical Endocrinology and metabolism 88 3184–3189.
Garrett HE Jr, Heidepriem RW III & Broadbent LP 2005 Ruptured aneurysm of the inferior thyroid artery: repair with coil embolization. Journal of Vascular Surgery 42 1226–1229.[CrossRef][Web of Science][Medline]
Jeganath V, McElwaine JG & Stewart P 2001 Ruptured superior thyroid artery from central vein cannulation: treatment by coil embolization. British Journal of Anaesthesia 87 302–305.
Kos X, Henroteaux D & Dondelinger RF 2001 Embolization of a ruptured aneurysm of the inferior thyroid artery. European Radiology 11 1285–1286.[CrossRef][Web of Science][Medline]
Lal G & Clark OH 2005 Thyroid, parathyroid and adrenal. In Schwartzs Principles of Surgery, edn 8, pp 1395–1470. Ed FC Brunicardi. New York: Mc Graw-Hill Companies, Inc.
Lookstein RA & Guller J 2004 Embolization of complex vascular lesions. Mount Sinai Journal of Medicine 71 17–28.[Medline]
Lorenz K, Brauckhoff M, Behrmann C, Sekulla C, Ukkat J, Brauckhoff K, Gimm O & Dralle H 2005 Selective arterial chemoembolization for hepatic metastases from medullary thyroid carcinoma. Surgery 138 986–993.[CrossRef][Web of Science][Medline]
Perona F, Barile A, Oliveri M, Quadri P & Ferro C 1999 Superior thyroid artery lesion after US-guided chemical parathyroidectomy: angiographic diagnosis and treatment by embolization. Cardiovascular and Interventional Radiology 22 249–250.[CrossRef][Web of Science][Medline]
Ramos HE, Braga-Basaria M, Haquin C, Mesa CO, Noronha L, Sandrini R, Carvalho Gde A & Graf H 2004 Preoperative embolization of thyroid arteries in a patient with large multinodular goiter and papillary carcinoma. Thyroid 14 967–970.[CrossRef][Web of Science][Medline]
Seldinger SI 1953 Catheter replacement of the needle in percutaneous arteriography; a new technique. Acta Radiologica 39 368–376.[Web of Science][Medline]
Smit JW, Vielvoye GJ & Goslings BM 2000 Embolization for vertebral metastases of follicular thyroid carcinoma. Journal of Clinical Endocrinology and Metabolism 85 989–994.
Tazbir J, Dedecjus M, Kaurzel Z, Lewinski A & Brzezinski J 2005 Selective embolization of thyroid arteries (SETA) as a palliative treatment of inoperable anaplastic thyroid carcinoma (ATC). Neuro Endocrinology Letters 26 401–406.[Medline]
Van Tol KM, Hew JM, Jager PL, Vermey A, Dullaart RP & Links TP 2000 Embolization in combination with radioiodine therapy for bone metastases from differentiated thyroid carcinoma. Clinical Endocrinology 52 653–659.[CrossRef][Medline]
Xiao H, Zhuang W, Wang S, Yu B, Chen G, Zhou M & Wong NC 2002 Arterial embolization: a novel approach to thyroid ablative therapy for Graves disease. Journal of Clinical Endocrinology and Metabolism 87 3583–3589.
Zhao W, Gao BL, Yang HY, Li H, Song DP, Xiang ST & Shen J 2007 Thyroid arterial embolization to treat Graves disease. Acta Radiologica 48 186–192.[CrossRef][Web of Science][Medline]
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