Cystic thyroid nodules
- Douglas S Ross, MD
Douglas S Ross, MD
- Section Editor — Thyroid Disease
- Professor of Medicine
- Harvard Medical School
Thyroid nodules are common, and a large proportion has mixed cystic and solid components. In some studies, a nodule is called a cyst only if it is predominantly cystic on ultrasonography, but in others the term is applied to nodules that are predominantly solid but have small areas of cystic degeneration. Thus, depending upon the criteria used, up to 50 percent of solitary thyroid nodules are cystic. Most recur after fine needle aspiration. The appropriate evaluation and management of patients with cystic thyroid nodules is an area of controversy.
This topic review will focus on the unique challenges presented by patients with cystic thyroid lesions. The general approach to thyroid nodules is reviewed separately. (See "Diagnostic approach to and treatment of thyroid nodules".)
Like most thyroid nodules, cystic thyroid nodules often come to attention when noted by the patient or as an incidental finding during a routine physical examination or radiologic procedure such as carotid ultrasonography, computed tomography (CT), or magnetic resonance imaging (MRI) of the neck (so-called "thyroid incidentalomas") .
However, some patients develop symptoms, and cystic thyroid lesions (not subacute thyroiditis) are the most common cause of thyroid pain. As an example, sudden hemorrhage or hemorrhagic infarction of a solid thyroid nodule can result in a predominantly cystic and painful neck mass. Even relatively small hemorrhagic cysts of only 1 to 2 mL may be associated with considerable neck discomfort and dysphagia. More extensive hemorrhage may cause hoarseness and vocal cord paralysis and may compromise the airway, especially if the nodule is located within or below the thoracic inlet . (See "Clinical presentation and evaluation of goiter in adults", section on 'Obstructive symptoms'.) In addition, chronic intermittent degeneration of a thyroid tumor can result in intermittent neck discomfort.
True simple thyroid cysts lined by benign epithelial cells are rare. As an example, in one ultrasound study of 1985 patients with 3483 nodules larger than 10 mm, there were only seven completely cystic nodules . Most cystic nodules are partly solid structures that have undergone cystic degeneration (mixed or complex nodules). Complex nodules are common. In a review of 1128 patients with 1458 thyroid nodules who underwent ultrasound-guided fine needle aspiration (FNA), 53.5 percent were partially cystic, with 13.7 percent described as >75 percent cystic .
- Tan GH, Gharib H. Thyroid incidentalomas: management approaches to nonpalpable nodules discovered incidentally on thyroid imaging. Ann Intern Med 1997; 126:226.
- Massoll N, Nizam MS, Mazzagerri EL. Cystic thyroid nodules: Diagnostic and therapeutic dilemmas. The Endocrinologist 2002; 12:185.
- Frates MC, Benson CB, Doubilet PM, et al. Prevalence and distribution of carcinoma in patients with solitary and multiple thyroid nodules on sonography. J Clin Endocrinol Metab 2006; 91:3411.
- Alexander EK, Heering JP, Benson CB, et al. Assessment of nondiagnostic ultrasound-guided fine needle aspirations of thyroid nodules. J Clin Endocrinol Metab 2002; 87:4924.
- de los Santos ET, Keyhani-Rofagha S, Cunningham JJ, Mazzaferri EL. Cystic thyroid nodules. The dilemma of malignant lesions. Arch Intern Med 1990; 150:1422.
- Cusick EL, McIntosh CA, Krukowski ZH, Matheson NA. Cystic change and neoplasia in isolated thyroid swellings. Br J Surg 1988; 75:982.
- Hiromura T. [Ultrasonography of cystic thyroid nodules: sonographic-pathologic correlation]. Nihon Igaku Hoshasen Gakkai Zasshi 1994; 54:500.
- Lee MJ, Kim EK, Kwak JY, Kim MJ. Partially cystic thyroid nodules on ultrasound: probability of malignancy and sonographic differentiation. Thyroid 2009; 19:341.
- Lin JD, Hsuen C, Chen JY, et al. Cystic change in thyroid cancer. ANZ J Surg 2007; 77:450.
- Henrichsen TL, Reading CC, Charboneau JW, et al. Cystic change in thyroid carcinoma: Prevalence and estimated volume in 360 carcinomas. J Clin Ultrasound 2010; 38:361.
- Werk EE Jr, Vernon BM, Gonzalez JJ, et al. Cancer in thyroid nodules. A community hospital survey. Arch Intern Med 1984; 144:474.
- Belfiore A, La Rosa GL, La Porta GA, et al. Cancer risk in patients with cold thyroid nodules: relevance of iodine intake, sex, age, and multinodularity. Am J Med 1992; 93:363.
- Ewing CA, Kornblut A, Greeley C, Manz H. Presentations of thyroglossal duct cysts in adults. Eur Arch Otorhinolaryngol 1999; 256:136.
- Deane SA, Telander RL. Surgery for thyroglossal duct and branchial cleft anomalies. Am J Surg 1978; 136:348.
- Majumdar, P, Ghosh, DP. Hydatid cyst of thyroid. Indian J Surg 1970; 32:496.
- Ginsberg J, Young JE, Walfish PG. Parathyroid cysts. Medical diagnosis and management. JAMA 1978; 240:1506.
- Simeone JF, Daniels GH, Mueller PR, et al. High-resolution real-time sonography of the thyroid. Radiology 1982; 145:431.
- Onal IK, Dağdelen S, Atmaca A, et al. Hemorrhage into a thyroid nodule as a cause of thyrotoxicosis. Endocr Pract 2006; 12:299.
- American Thyroid Association (ATA) Guidelines Taskforce on Thyroid Nodules and Differentiated Thyroid Cancer, Cooper DS, Doherty GM, et al. Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid 2009; 19:1167.
- Redman R, Zalaznick H, Mazzaferri EL, Massoll NA. The impact of assessing specimen adequacy and number of needle passes for fine-needle aspiration biopsy of thyroid nodules. Thyroid 2006; 16:55.
- Melliere D, Massin JP, Calmettes C, et al. [The risk of malignancy in cold thyroid nodules. 607 operated cases]. Presse Med 1970; 78:311.
- Faquin WC, Cibas ES, Renshaw AA. "Atypical" cells in fine-needle aspiration biopsy specimens of benign thyroid cysts. Cancer 2005; 105:71.
- Rosen IB, Provias JP, Walfish PG. Pathologic nature of cystic thyroid nodules selected for surgery by needle aspiration biopsy. Surgery 1986; 100:606.
- McCowen KD, Reed JW, Fariss BL. The role of thyroid therapy in patients with thyroid cysts. Am J Med 1980; 68:853.
- Miller JM, Zafar SU, Karo JJ. The cystic thyroid nodule. Recognition and management. Radiology 1974; 110:257.
- Del Prete S, Caraglia M, Russo D, et al. Percutaneous ethanol injection efficacy in the treatment of large symptomatic thyroid cystic nodules: ten-year follow-up of a large series. Thyroid 2002; 12:815.
- Bennedbaek FN, Hegedüs L. Treatment of recurrent thyroid cysts with ethanol: a randomized double-blind controlled trial. J Clin Endocrinol Metab 2003; 88:5773.
- Valcavi R, Frasoldati A. Ultrasound-guided percutaneous ethanol injection therapy in thyroid cystic nodules. Endocr Pract 2004; 10:269.
- Yasuda K, Ozaki O, Sugino K, et al. Treatment of cystic lesions of the thyroid by ethanol instillation. World J Surg 1992; 16:958.
- Cho YS, Lee HK, Ahn IM, et al. Sonographically guided ethanol sclerotherapy for benign thyroid cysts: results in 22 patients. AJR Am J Roentgenol 2000; 174:213.
- Zingrillo M, Torlontano M, Chiarella R, et al. Percutaneous ethanol injection may be a definitive treatment for symptomatic thyroid cystic nodules not treatable by surgery: five-year follow-up study. Thyroid 1999; 9:763.
- Ryan WG, Dwarakanathan A. Minor complication of thyroid cyst sclerosis with tetracycline. Arch Intern Med 1986; 146:201.
- Jeong WK, Baek JH, Rhim H, et al. Radiofrequency ablation of benign thyroid nodules: safety and imaging follow-up in 236 patients. Eur Radiol 2008; 18:1244.
- Sung JY, Kim YS, Choi H, et al. Optimum first-line treatment technique for benign cystic thyroid nodules: ethanol ablation or radiofrequency ablation? AJR Am J Roentgenol 2011; 196:W210.
- Jang SW, Baek JH, Kim JK, et al. How to manage the patients with unsatisfactory results after ethanol ablation for thyroid nodules: role of radiofrequency ablation. Eur J Radiol 2012; 81:905.
- Sung JY, Baek JH, Kim KS, et al. Single-session treatment of benign cystic thyroid nodules with ethanol versus radiofrequency ablation: a prospective randomized study. Radiology 2013; 269:293.
- Døssing H, Bennedbæk FN, Hegedüs L. Interstitial laser photocoagulation (ILP) of benign cystic thyroid nodules--a prospective randomized trial. J Clin Endocrinol Metab 2013; 98:E1213.
- Døssing H, Bennedbæk FN, Hegedüs L. Long-term outcome following interstitial laser photocoagulation of benign cold thyroid nodules. Eur J Endocrinol 2011; 165:123.
- Døssing H, Bennedbaek FN, Bonnema SJ, et al. Randomized prospective study comparing a single radioiodine dose and a single laser therapy session in autonomously functioning thyroid nodules. Eur J Endocrinol 2007; 157:95.
- CLINICAL PRESENTATION
- Thyroid adenomas and cancers
- Thyroglossal duct cysts
- Hydatid cysts
- Serum TSH
- Thyroid ultrasonography
- Fine needle aspiration
- - Indications
- - Ultrasound-guided FNA
- - Non-diagnostic FNA results
- Thyroid scintigraphy
- Benign cystic nodules
- - Aspiration
- - Surgery
- - Percutaneous interventional ultrasound-guided therapy
- Ethanol ablation
- Radiofrequency ablation
- Interstitial laser photocoagulation
- Non-diagnostic cystic nodules
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS