User login

We offer our registered users tailored information, free online courses and exclusive content.

You have an old EXCEMED account ...

Our platform has been renewed. All users registered at any of the old websites are kindly requested to reset their password. Why is this?

... or you lost your password?

Scientific Highlights: 2016 Asia Pacific conference on thyroid diseases - clinical features and management

Scientific Highlights: 2016 Asia Pacific conference on thyroid diseases - clinical features and management
  • Endocrinology and metabolism
  • Thyroid disorder

Resource type

Article

Endocrinologists, surgeons and other healthcare professionals involved in the diagnosis and management of patients with thyroid disorders mainly from Asia Pacific, attended this live educational conference to share the most recent international guidelines for the care of thyroid disorders and apply them in clinical management in daily practice. During practice sessions and using clinical case studies there was the opportunity for the delegates to interact and share experience and ideas.

The prevalence of thyroid diseases is high worldwide and particular in Asia and Pacific areas, which represents an increasing medical problem in clinical practice with serious implications in a number of conditions including obesity, cardiac disease and cardiovascular disease. The problem of thyroid disease is especially acute in the Philippine population – a survey in 2012 reported a prevalence of 8.5%, predominantly subclinical disease but also the highest incidence of thyroid carcinoma in the world. Furthermore, in the Philippines thyroid carcinoma has unusual features compared with other races with a more aggressive course and higher risk of recurrences. Thus the management of TD in the Philippines represents a challenge for the health care system with respect to early diagnosis, prevention and standard of care.

This report highlights important topics discussed at this two-day meeting on thyroid disorders, the learning objectives of which were to:

  • Consider the relevance of thyroid disease and the clinical implications
  • Apply international standards for managing conditions such as subclinical hypothyroidism, hyperthyroidism and autoimmune thyroid disorders
  • Discuss problematical aspects of thyroid diseases with colleagues and international experts through the analysis of selected clinical cases
  • Acquire practical clinical skills on managing thyroid nodules through the clinical skill section on ultrasound, fine needle cytoaspiration and thyroid cytology

Session I. Thyroid diseases: overview and early diagnosis

Thyroid diseases in Asia Pacific – impact and epidemiology

Nemencio A. Nicodemus Jr. (Philippines) opened the conference by presenting data on epidemiology of thyroid disease including iodine deficiency, Graves’ disease, Hashimoto’s thyroiditis and thyroid cancer, in the Asia Pacific region. The population of several countries such as Indonesia, Republic of Korea and Philippines are iodine deficient. In particular, school-age children are affected. In 2010 iodine deficiency was the 79th largest contributor to disability-adjusted life years (DALYs) and the 33rd highest contributing disease to years lived with disability in South Asia.

Both deaths and heart failure due to iodine deficiency increased from 1990 and 2010 (67.7% and 33.3% respectively). [1] Furthermore, Graves’ disease is more common in Blacks and Asian/Pacific Islanders than in Whites probably due to different environmental exposures and genetics. [2] However, the average percent change in thyroid cancer is higher in Whites than Asians/Pacific Islanders. [3]

The increasing incidence of thyroid cancer in all racial and ethnic groups could be due to an increase in the diagnosis of subclinical thyroid cancers and use of ultrasonography-guided fine-needle aspiration biopsies, differential exposure to ionizing radiation and iodine deficiency or excess or a true increase in thyroid cancer. [3] Thyroid cancer rates are also high in Southeast Asian women living in the USA, probably due to greater prevalence of goiter and thyroid nodules and dietary patterns. [4] Moreover, some trace elements associated with volcanic activity have been implicated in thyroid tumorigenesis. [5]

Between 1990 and 2010 thyroid cancer mortality increased by 50.2% and is ranked 92 as a disease that contributes to mortality (in South Asia it is ranked 94th). Over the same period thyroid cancer increased DALYs by 44.4%. [1]

Professor Nicodemus stated that there is a need for more strict implementation of universal salt iodization in the Asia Pacific region and early detection of subclinical TD using more accurate imaging technologies to facilitate early detection. There is a need for more studies on the effects of environmental factors on the prevalence of TD in this region. [327 words]

References

  1. Kalra S, et al. Thyroid Res Pract 2013;10:89–90.
  2. Macloed DSA, et al. JAMA 2014;311;1563–5.
  3. Magreni A, et al, JAMA Otolaryngol Head Neck Surg 2015;141:319–23.
  4. Haselkorn T, et al. Cancer Epidemiology, Biomarkers and Prevention 2003;12:144–50.
  5. Duntas LH, et al. Hormones 2009;8:249–53.

 

Subclinical hyperthyroidism – diagnosis and treatment

Bernadette Biondi (Italy) explained that the prevalence of subclinical hyperthyroidism varies from 0.7–11% depending on the diagnostic criteria, age and sex of the patients, sensitivity of the thyroid-stimulating hormone (TSH) assay and iodine intake of the population. Endogenous causes include Graves’ disease, toxic adenoma and toxic multinodular goiter.

In 2015 the European Thyroid Association published guidelines for the diagnosis and treatment of endogenous subclinical hyperthyroidism (Figure 1). [1] These guidelines highlighted causes of low serum TSH such as pituitary or hypothalamic insufficiency and severe non-thyroidal illness. Diagnosis of subclinical hyperthyroidism involves three levels:

  • Level I, to establish the diagnosis of persistent subclinical hyperthyroidism
  • Level II, to establish the aetiology of subclinical hyperthyroidism
  • Level III, to establish the risks associated with subclinical hyuperthyroidism and appropriate treatment.

If persistent subclinical hyperthyroidism is untreated there is a risk of progression to overt hyperthyroidism, osteoporosis and fracture and cardiovascular disease (atrial fibrillation, heart failure, coronary heart disease event, all cause mortality and cardiovascular mortality). [2] The risks of coronary heart disease mortality and atrial fibrillation are greater in adults with grade 2 subclinical hyperthyroidism. Older patients more frequently have persistent subclinical hyperthyroidism or progress to overt disease compared with those with grade1 subclinical hyperthyroidism. Furthermore, lower TSH is associated with a higher rate of fracture, particularly hip. [3]

Several meta-analyses have been published on the consequences of subclinical hyperthyroidism but none show evidence that treatment is effective in improving the risks associated with untreated subclinical hyperthyroidism. However, the 2015 European Thyroid Association Guidelines recommend treatment in patients over 65 years with grade 2 subclinical hyperthyroidism and for those older than 65 years with grade 1 subclinical hyperthyroidism. Furthermore patients younger than 65 years with grade 2 subclinical hyperthyroidism should be treated with cardioselective β-blockers and/or therapies directed toward the thyroid dysfunction if they have persistent disease or symptoms of thyroid hormone excess.

Professor Biondi emphasized that appropriate management for subclinical hyperthyroidism remains controversial. Adequately powered studies with relevant clinical outcomes are need to determine if treatment of subclinical hyperthyroidism can prevent or improve the cardiovascular and skeletal risks associated with grade 2 subclinical hyperthyroidism in elderly patients.

Figure 1: 2015 European Thyroid Association guidelines on diagnosis and treatment of endogenous subclinical hyperthyroidism

 

References

  1. Biondi B, et al. Eur Thyroid 2015; 4:149-63.
  2. Collet T-H, et al. Arch Intern Med 2012;172:799–809.
  3. Blum MR, et al. JAMA 2015;313:2055–65.

 

Subclinical hypothyroidism – reducing the risk of cardiovascular disease

Salman Razvi (UK) posed the question of whether symptoms are related to hypothyroidism and will they improve with treatment. The Colarado Thyroid Prevalence Study showed that more euthyroid patients reported symptoms than those with an elevated thyrotropin (TSH level). [1]

The goals of management are to improve symptoms, reduce the risk of cardiovascular disease and improve overall health and survival. A randomized, controlled trial of the effect of thyroxine replacement on cognitive function in elderly subjects with subclinical hypothyroidism found no evidence that the treatment improved cognitive function. [2] Another study in patients with subclinical hypothyroidism found that treatment with L-thyroxine resulted in a significant improvement in cardiovascular risk factors and symptoms of tiredness compared with placebo. [3]

Dr Razvi described an innovative ongoing study to investigate the effect of levothyroxine in subclinical hyperthyroidism post-acute myocardial infarction patients. [4] Subclinical hyperthyroidism is associated with adverse outcomes especially in younger patients and in post myocardial situations. However, older people with a raised serum TSH may not have a poor prognosis. Treating subclinical hyperthyroidism improves cardiovascular risk factors and symptoms and may improve cardiovascular risk in younger patients.

  1. Canaris GJ, et al. Arch Intern Med 2000;160:526–34.
  2. Parle J, et al. J Clin Endocrinol Metab 2010;95:3623–32.
  3. Surks MI, et al. J Clin Endocrinol Metab 2007;92:4575–82.
  4. Jabbar A, et al. Trials 2015;16:115.

 

Thyroid autoimmune disease and associated autoimmune disorders

George J. Kahaly (Germany) summarized the prevalence of autoimmune polyglandular syndromes of the parathyroid, adrenal, gonads, pancreas and thyroid in both juveniles and adults emphasising that it is <1/100 in juveniles and 1/10 in adults. [1]

Thyroid autoimmune diseases include Graves’ disease and Hashimoto’s thyroiditis. The time interval between the subsequent endocrine disease varies. For example if type 1 diabetes occurs first the interval is 18 years (mean) before thyroid disease (97%) but if thyroid disease is first type 1 diabetes occurs 12 years (mean) later (58%). [2]

Professor Kahaly proposed an algorithm to assess and screen patients with autoimmune disease. Patients with thyroid autoimmune disease should undergo serological screening for organ specific antibodies once a year and if positive functional screening and serological screening (first degree relatives) should be implemented. (Figure 2)

Figure 2: Diagnostic screening for autoimmune disease [1]

References

  1. Kahaly GJ. Eur J Endocrinol, et al. 2009;161:11-20.
  2. Hansen MP, et al. World J Diabetes 2015;6:67–79.

 

Session II. Focus on thyroid cancer: Diagnosis, management and treatment

Thyroid nodules – risk factors and clinical management

Sun-Ynn Chia (Republic of Singapore) reminded delegates that although thyroid nodules are common, only 5% are malignant and of these 90% are differentiated thyroid cancer. [1,2]

The evaluation of thyroid nodules involves both history and clinical examination. A past history (e.g. irradiation, papillary cancer, Gardner’s or Cowden’s syndrome) and family history (papillary thyroid cancer in 1st degree relative, familial polyposis, Cowden’s syndrome) must be obtained together with current complaints (dysphonia, dysphagia, sudden growth). [3,4] Five percent of papillary thyroid cancer may be familial. [3,4]

Tests such as thyroid function, imaging and fine needle aspiration are used to investigate thyroid nodules. Moreover, the higher the level of TSH, the greater the risk of cancer. The American Thyroid Association 2015 Guidelines recommend that thyroid sonography should be performed in patients with known of suspected thyroid nodules. [5] However, no single or combined ultrasound feature has high diagnostic accuracy.

There are a number of treatment options in the management of benign module on fine needle aspiration. L-thyroxine suppressive therapy only results in >50% decrease in nodule volume in approximately 20% of patients and re-growth occurs immediately after cessation of treatment with atrial fibrillation and osteoporosis adverse effects. [6,7,8]. Percutaneous ethanol injection is effective in thyroid cysts but recurrence is common. [9]

Percutaneous laser ablation can be effective in patients unsuitable for or who refuse surgery, with similar efficacy to percutaneous radio frequency ablation but at a much lower cost. Radioactive iodine is indicated for the treatment of autonomous nodules with 90–100% success. [9] Surgery is used for >4cm nodules.

Professor Chia emphasized that it is important to follow up patients by ultrasound to identify significant growth. For differentiated thyroid cancer surgery is recommended.

References

  1. Frates MC, et al. J Clin Endocrinol Metab 2006;91:11–7.
  2. Werk EE, et al. Arch Intern Med 1984;144:474–6.
  3. Gharib H, et al. J Endocr Pract 2010;16:468–75.
  4. Haugen BR, et al. Thyroid 2016;26:1–133.
  5. Haugen BR, et al. Thyroid 2016;26: complete slide 16
  6. Berghout A, et al. Lancet 1990;336:193–7
  7. Sdano MT, et al. Otolaryngol Head Neck Surg 2005;133:391–6.
  8. Castro MR, et al. JCEM 2002;87:4151–
  9. Gharib et al. Endocrine Practice 2006;12:63–102.

 

Thyroid cancer: overview and peculiar aspects in Philippines

Nemencio A. Nicodemus Jr. (Philippines) gave an overview of the peculiar clinical feature of differentiated thyroid carcinoma in the Philippines and its impact on the healthcare system. In the Philippines the prevalence of goiter is increasing and 44% are nodular. In a cross sectional study the prevalence of iodine deficiency in patients with thyroid nodules was 63.4% and it may be a risk factor. [1]

In 1395 patients who had thyroid surgery (January 2006–December 2010) 29.7% were malignant with 86.3% female. [2] The most common cancer sites in Metro Manila and Rizal (1998–2002) are summarized in figure 3. [3] However while the incidence of thyroid cancer in this population is almost stable in males, it is increasing in females. [4] Factors that predict malignancy in thyroid nodules include a hard or firm nodule and the presence of microcalcifications (all P<0.001). [5]

A study of both Filipino and non-Filipino patients with thyroid cancer demonstrated that Filipino patients are significantly more likely to develop thyroid cancer recurrence and death. [6] Furthermore stratification of well-differentiated thyroid cancer based on recurrent risk factors will be helpful in guiding the intensity of treatment strategies and long-term thyroid cancer surveillance. [7]

Professor Nicodemis emphasized that after diagnosis and initial management of thyroid cancer, surveillance and monitoring is life-long. The loss of productivity due to illness and expense of surveillance and monitoring has a considerable impact on the cost for the patient. Currently patients pay for their health maintenance. Professor Nicodemis urged the government to increase its coverage for thyroid cancer management and monitoring since prognosis is good and treatment is cost effective.

Figure 3: Ten most common cancer sites in Metro Manila and Rizal (1998–2002) for both sexes

References

  1. Ejercito-De Jesus RE, et al. Phil J Internal Medicine 2008;46:27–34.
  2. Holgado JWA, et al, unpublished.
  3. Redaniel MTM, et al. Cancer in the Philippines 2008;4:[Cannot find this reference]
  4. Medina VM, et al, Cancer in the Philippines 2011;4
  5. Canete EJ, et al. Endocrinol Metab 2014;29:489–97.
  6. Kus LH, et al. Arch Otolaryngol Head Neck Surg 2010;136:138–42.
  7. Lo Ten, et al. Endocrinol Metab 2015;30:543–550.

 

Thyroid cancer surgery – clinical aspects.

Malfred Hernandez (Philippines) told delegates that guidelines recommend total or near-total thyroidectomy for all patients with well-differentiated thyroid cancer with a nodule size >1 cm in the largest diameter. For thyroid cancers ≤1 cm isolated, intrathyroidal and in the absence of cervical lymph node metastasis on preoperative ultrasound, thyroid lobectomy may be sufficient treatment.

Professor Hernandez highlighted 2 published surgical guidelines:

  • 2012 University of the Philippines – Philippines General Hospital; clinical practice guidelines for the management of well-differentiated thyroid carcinoma of follicular origin.
  • 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer

In previous international guidelines the critical tumor size was >4 cm and many guidelines recommend preoperative risk stratification prior to applying a certain surgical approach. However, based on 10-year clinical data, a more aggressive primary approach (total or near-total thyroidectomy) is now recommended for all thyroid cancers >1 cm.

The American Thyroid Association guidelines are summarized in figure 4. A preoperative cervical ultrasound is recommended for all adult patients with well-differentiated thyroid cancer. A frozen section is not recommended by most guidelines. Patients with well-differentiated cancer who had lobectomy as initial surgery should be offered completion thyroidectomy if certain criteria apply (>1 cm original tumor size, multifocal disease, nodal metastasis, gross residual tumor, extra-thyroidal extension, vascular invasion, aggressive histopathology, nodules in the contralateral lobe).

In surgery the recurrent laryngeal nerve and parathyroids must be identified and preserved, and the closure technique should be subcuticular with a penrose drain left for at least 24 hours. In addition, an external pressure dressing should be applies for 1 to 2 days.

Figure 4: 2015 American Thyroid Association guidelines [Hernandez slide 13]

Radioiodine treatment in thyroid cancer – safe and effective

Ruben Ogbac (Philippines) explained that radioactive iodine (RAI, I-131) is one of several isotopes of iodine and is taken up by follicular thyroid cells and emits both beta (therapy) and gamma (diagnosis) radiation. Alternatively, I-123 can be used for diagnostic purposes only. Indications for RAI include ablation, adjuvant treatment, treatment of residual and metastatic disease and imaging.

Ablation minimizes the risk of new papillary thyroid cancer in at risk patients, while treatment of residual or metastatic thyroid cancer decreases 30-year recurrence and disease-specific mortality rate by 50%.

Before commencing RAI treatment the patient must be prepared by having a low iodine diet, avoiding an iodine load and elevating TSH to at least 30 mIU/L with either thyroid hormone withholding/withdrawal or recombinant TSH. Uptake of RAI can be increased by lithium, mannitol, bexarotene or selumetinib.

The activity of RAI is determined by quantitative tumor density, blood dosimetry or fixed activity, with each method having advantages and disadvantages.

Several issues must be considered when the patient is discharged. For example the radiation exposure to caring individual should not exceed 5 mSv/yr and to the public, children or pregnant women 1 mSv/yr.

Professor Ogbac reiterated that RAI administration is generally safe and easy to perform, with data suggesting an improved overall survival in many higher risk patients.

 

Session III. Highlights on thyroid cancer

Clinical management of anaplastic thyroid cancer

Rapid histological confirmation of the diagnosis of anaplastic thyroid cancer (ATC) is required said Mafauzy Mohamed (Malaysia). The frequency of thyroid malignancies is increasing, with median global prevalence 3.6%. In the US, thyroid malignancies represent 2.5% of all cancers, while ATC accounts for 1.7% of all thyroid cancers. The median survival for ATC patients is 5 months with a 20% 1-year survival rate. However, in some countries prevalence of ATC has dramatically declined partly due to dietary iodine and better management. [1]

Differential diagnosis using histopathology and immune-histochemistry allows ATC to be distinguished from other tumors. Preoperative staging procedures can then be undertaken such as ultrasound to assess involvement of central and lateral lymph node basins and to assist in evaluating airway patency. MRI and/or CT scans detect regional disease and exclude distant metastasis.

Surgery and loco-regional radiation therapy (with or without systemic therapy) should be considered for patients with resectable disease and no distant metastases. In contrast patients with loco-regionally confined but unresectable disease should have radiotherapy with or without systemic therapy. In surgery, gross tumor resection, not debulking is the goal and total lobectomy or total/near-total thyroidectomy with a therapeutic lymph node dissection should be performed in patients with intrathyroidal ATC.

Radiation should be started as soon as the patient had recovered from neck surgery (usually 2-3 weeks later). Higher doses (>50 Gy) give better responses. Systemic chemotherapy (taxane, and/or anthracyclines and/or platin) can also begin once the patient has recovered from surgery.

Metastatic disease can occur in the brain, bone, lung and liver and requires aggressive treatment, although success is doubtful. Professor Mohamed reminded delegates that hospice and palliative care is also important in managing patients with stage IVC disease.

References

  1. Smallridge RC, et al. Thyroid 2012;22:1104–39.

 

New ATA guidelines on differentiated thyroid cancer

Roberto Mirasol (Philippines) summarized the 2015 American Thyroid Association guides commenting that lobectomy may be appropriate for low risk disease. Ultrasound can be used for pre-operative management of differentiated thyroid cancer and neck ultrasound for contralateral lobe and central and lateral neck lymph nodes is recommended for all patients undergoing throidectomy with suspicious or malignant findings on fine needle aspiration. [1] A summary of an initial treatment strategy is illustrated in figure 5. [2,3]

The guidelines recommend lobectomy for indeterminate solitary nodule, while radioiodine ablation in lieu of completion thyroidectomy is not recommended. Total thyroidectomy should be performed for >4cm indeterminate nodules. Risk is stratified as low, intermediate or high according to a number of findings including the presence of metastases and histology. It is important to consider post-operative disease status when deciding on an additional course of therapy (I-131, surgery etc).

The guideline gives recommendations for the use of radioactive iodine therapy in terms of which patients should be considered for this treatment, the dose (high or low – low doses of 30 mci are preferred) and preparing patients (e.g. low iodine diet).

It is important to continually modify the initial estimates of recurrence risk during follow-up. Several responses are possible from excellent (no clinical, biochemical or structural evidence of disease), biochemical incomplete (abnormal thyroglobulin values in the absence of localizable disease) and structural incomplete response (persistent or newly identified locoregional or distant metastasis).

Professor Mirasol strongly stressed that the American Thyroid Association risk of recurrence stratification system should be employed and the risk estimates periodically re-assessed

Figure 5: Initial treatment strategy for thyroid cancer

References

  1. Wells AS, et al. Thyroid 2016;25:567–610.
  2. Sherman SI, et al. Lancet 2003;361:501–11.
  3. Kinder BK, et al. Curr Opin Oncol 2003;15:71–7.
  4. Mazzaferri EL, et al. J Clin Endocrinol Metal 2001;86:1447–63.

 

Session IV. Thyroid nodules in clinical practice: From ultrasound features to cytological diagnosis

Thyroid ultrasonography – normal findings in thyroid and neck

Roberto Mirasol (Philippines) likened thyroid ultrasonography as an extension of the physical examination and to the thyroidologist is as the stethoscope to the cardiologist. It is a very sensitive tool giving real time information and can detect 2-3 mm nodules, however it lacks specificity.

It has many advantages, including its use in pregnancy, sensitivity and using no radiation. Ultrasound allows the classification and determination of the location of a palpable lump and the evaluation of adjacent structures and can identify the cause for hyper and hypothyroidism. It also facilitates differential diagnosis and post-treatment surveillance.

Professor Mirasol reiterated that ultrasound has an important role in virtually all aspects of the evaluation of the neck from thyroid anatomy to neck masses outside the thyroid.

 

Thyroid ultrasonography – principal pathological findings

Enrico Papini (Italy) described ultrasound as a sensitive examination technique which may be specific for thyroid carcinoma (particularly papillary). However, the main problem when thyroid nodules are detected by ultrasound is to rule out malignancy as most are asymptomatic. [1,2] No single ultrasound feature is both sensitive and specific for cancer. However, an ultrasound reporting system for thyroid nodules stratifying cancer risk for clinical management provides a basis for identifying malignancy. [3]

The American Thyroid Association 2015 thyroid nodule and cancer guidelines recommended an ultrasound classification system with 5 major ultrasound patterns with each class related to different risk of malignancy with increasing indication to fine needle aspiration. [4] The British Thyroid Association guidelines for the management of thyroid cancer recommend that the practitioner should identify signs that allow differentiation of thyroid nodules into benign (U2), equivocal/indeterminate (U3), suspicious (U4) or malignant (U5). [5] Finally the American Association of Clinical Endocrinologists, American College of Endocrinology and Associazione Medici Endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules (2016 update) recommends identification of low-risk, intermediate risk and high-risk US lesions. [6]

Professor Papini stressed that ultrasound signs should be used in summation to determine whether fine needle aspiration should be performed and ultrasound classification systems are essential for assessing risk of malignancy and guiding actions.

References

  1. Gharib H, et al. Endocrinol Metab Clin North Am 2007;36:707–35.
  2. Hegedus L, et al. NEJM 2004;351:1764–71.
  3. Horvath, et al. J Clin Endocrinol Metab 2009;90:1748–51.
  4. Haugen B, et al. Thyroid 2006;26:1–133.
  5. Perros P, et al. Clin Endocrinol 2014;81[Suppl 1]:1–122.
  6. Gharib H, et al.Endocr Pract 2016;22:622–39.

 

Ultrasound fine needle cyto-aspiration

Sjoberg A. Kho (Philippines) gave an overview of the indications and advantages of ultrasound fine needle cyto-aspiration including the required materials, preparation, methods and techniques.

There are many indications for this technique such as nodule size <1 cm and deeper nodules, small suspicious lymphadenopathy and occasional parathyroid edenoma, incidentalomas in patients with high risk factors for thyroid cancer (such as exposure to therapeutic or accidental radiation) and residual/recurrent lesions of thyroid cancer. [1,2]

Before commencing ultrasound fine needle cyto-aspiration signed consent is needed and the hemorrhagic risk should be assessed. An anesthetic may be needed and a high-frequency (7.5–15 mHz) linear probe used. Various techniques can be used including parallel or perpendicular and aspiration or capillary.

The parallel approach helps to minimize the number of needle-generated reflected echoes across the plane of sound wave, whereas in the perpendicular approach a shorter needle may be used and it is less likely that the caratid artery or jugular vein may be punctured. [3]

Dr Kho stated that the main difference between the aspiration and the non-aspirational techniques is the use of suction, while the capillary technique is useful in very hypervascular nodules.

References

  1. Baskin HJ, et al. Thyroid Ultrasound and Ultrasound-Guided FNA 3rd Ed. 2013;pp. 267–82.
  2. 2013 European Guidelines on US of Postoperative Management of Patients with Thyroid Cancer.
  3. Kim MJ, et al. RadioGraphics 2008;28:1869–86.

 

Thyroid cytology – features and interpretation

Jose C. Avila (Philippines) said that the fine needle aspiration biopsy procedure is an important and established diagnostic tool in the evaluation of thyroid nodules. The 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer describe fine needle aspiration biopsy as the procedure of choice in the evaluation of thyroid nodules, when clinically indicated. It is the most accurate and cost-effective method for evaluating thyroid nodules (Figure 6). [1]

When examining a fine needle aspiration biopsy the pathologist considers the cell types aspirated, checking the patterns made by the cells and benign or malignant feature of each cell as well as the background.

The Bethesda system is a classification system for thyroid cytology and takes into consideration if the biopsy is:

  • Non-diagnostic (unsatisfactory for evaluation)
  • Benign (<1% risk of malignancy)
  • Atypia of undetermined significance (does not fit in any category)
  • Suspicious for a follicular neoplasm/follicular neoplasm (surgery usually needed for definitive diagnosis)
  • Suspicious for malignancy (papillary or medullary carcinoma, malignant lymphoma, metastatic cancer)
  • Malignant (papillary, medullary, anaplastic or metastatic carcinoma, lymphoma, other)

Professor Avila outlined a ‘modified’ Bethesda applicable to the local setting which included repeating the fine needle aspiration biopsy immediately to resolve atypical smears and this also almost always solves the problem of suspicious/atypical cases.

Molecular testing, includes gene mutation analysis, next generation sequencing, gene expression profiling and microRNA profiling of thyroid fine needle aspiration biopsies, is a promising development for use in fine needle aspiration biopsy.

Figure 6: 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer.

References

  1. Haugen B, et al. Thyroid 2006;26:1–133.

The final session of the conference consisted of practical sessions on the following:

  • Ultrasound features of thyroid nodules
  • Ultrasound features of malignant lymph nodes
  • Ultrasound guided fine needle cytoaspiration
  • Thyroid cytology preparation and examination

Terms of use

This is a copyrighted resource for the sole purpose of education. Resource may be used for classroom training only and must remain as is, including the branding and EXCEMED logo. It is backed by a publishing license, signed by the author.

Regional conference
Manila, Philippines
Apr 16 - 17, 2016
Target audience
This course is meant for endocrinologists, surgeons and other HCPs involved in the diagnosis and management of patients with thyroid disorder mainly from Asia Pacific.
by Excemed
Endocrinology and metabolism