Management of an Incidental Thyroid Nodules in primary health care.

Management of an Incidental Thyroid Nodules in primary health care..

Clinical scenario. A 35-year-old lady. presents to her GP with a painless lump in her neck . The lump gradually increased in size over the last few months. She has no history of weight loss, diarrhoea or heat intolerance. There is no history of change of voice or difficulty in swallowing. Her mother was diagnosed with thyroid cancer 10 years ago..

Examination. She has a 2 cm firm thyroid nodule palpable in the midline. A 1.5 cm cervical lymph node is also palpable in the right supra-clavicular fossa. She is reviewed on an urgent basis in a combined endocrine-surgical thyroid clinic and undergoes FNAC on the same day. The results of FNAC are classed as diagnostic category Thy 3..

Investigations. RFTs , electrolytes ,LFTs ,FBC , CRP, Anti TPO antibodies and TFTs with normal levels..

What is the possible diagnosis?.

Thyroid incidental nodule with euthyroid.

Discussion.

Introduction. An incidental thyroid nodule is a clinical condition where a nodule not previously found or suspected clinically been detected by non-intentional radiological study (Hoang et al, 2015). Detection of thyroid nodule(s) , depends on the method used for examination (Dean and Gharib, 2008): By palpation : 2 – 6%. By ultrasonography : 19 – 35%. By autopsy data : 8- 65%. By CT scan : 16.8% (Yoon et al ,2008)..

Epidemiology (Yoon et al, 2008). Thyroid cancer is a rare cancer , represent 1% of all cancers. The risk of malignancy in thyroid nodules is about 10% . The over all survival rate of differentiated thyroid cancer 80 -90%. 5-20% develop recurrence either locally or regionally. 10 – 15% developed distance metastasis..

Red Flag Symptoms and Signs. The clinical importance of incidental thyroid nodule(s) is to exclude thyroid malignancy (Kroeker et al , 2014). Family history of thyroid cancer. History of previous irradiation or exposure to high irradiation environment. Young or old age with thyroid nodule. Unexplained stridor or hoarseness of voice with goitre. Painless , rapidly enlarged thyroid nodule within short time. Palpable cervical lymph nodes. Increasing and persistent pain for long time..

Investigations. Thyroid function test: This is done to exclude hyperthyroidism Some evidence showed that increase level of thyroid stimulating hormone increase the risk of thyroid cancer (Boelaert et al,2006) . 2) Ultrasonography (Baskin, 2004): High definition ultrasonography can provide: Valuable information about the characteristics of the nodule (size, anatomy of the thyroid gland and adjacent structures in the neck). Potential risk of malignancy. Ultrasound guidance increases the accuracy of fine needle aspiration—from 85% to 95% ..

Ultrasound features suggestive of thyroid malignancy (Ahuja et al,2003).

Continue ……... 3) Fine needle Aspiration Cytology : This is done to find out the nature of the nodule. The overall sensitivity and specificity of FNAC in predicting malignancy were 88 and 84%, respectively ( Boelaert et al,2006) . 4) MRI and CT screening is indicated if : Cervical lymphadenopathy is present. Fixed thyroid mass is present..

Thy classification based on FNAC results.

Management. The British thyroid society based its recommendations for general practitioners on the Thyroid function tests ,history and clinical examination on the (Perros et al, 2014). Based on the findings , the recommendation direct the patient to either refer to specialist clinics or continue follow at general practice. The aim is to reduce delay in malignancy diagnosis..

Thyroid examination. Thyroid Right lobe Isthmus Left lobe — Sternocleidomastoid muscle Internal carotid artery Thyroid cartilage Cricothyroid muscle Cricothyroid ligament/ cricoid cartilage Trachea.

Inspection. Inspection: from front and side. Look for neck enlargement /goitre. Look for scars and skin changes. Look for dilated veins. Swallow : movement of thyroid. Tongue protrusion test : differentiate between thyroid and thyroglossal cyst..

Palpation. Tracheal deviation. From behind : palpate both lobes +isthmus to: Size. Shape (smooth vs irregular). Consistency (hard vs comprisable). Nodules (size ,number , mobility ,consistency). Tenderness. Mobility – swallow. Lymph nodes (supraclavicular)..

Auscultation. Auscultate the thyroid and carotid for arterial bruit..

Percussion. Percussion for thoracic inlet to exclude thyroid extension.

Special tests. Pemberton's sign is used to evaluate venous obstruction in patients with goitres. The sign is positive when bilateral arm elevation causes facial plethora. It has been attributed to a “cork effect” resulting from the thyroid obstructing the thoracic inlet, thereby increasing pressure on the venous system.

Tongue protrusion test. While protrusion of the tongue , the midline neck mass (thyroglossal cyst) will move upword ..

Technical points during thyroid examination.

A, The thyroid is examined from behind, with the patient in a sitting position, avoiding hyperextension of the neck. B, The exploring fingers determine the extent of the gland, after which attention is directed to the size, consistency, and presence of any nodules. C, By using the fingertips alternately to displace the gland to the contralateral side, an appreciation of deeper abnormalities may be gained. This is particularly effective when the sternocleidomastoid muscle is thickened, in which case direct palpation would be difficult. D, Examination for lymphadenopathy is conducted in a routine manner but should be especially thorough in the presence of a thyroid nodule..

Management at PHC.

Step 1 : Patient attend to GP with suspicious of thyroid nodule. Step 2 : Examination confirm thyroid nodule : 1) With recent stridor due to nodule immediate referral (same day). 2) No symptoms : Do thyroid function tests: A) If normal TFTs with one of the followings - urgent referral to specialist clinic (within 2weeks): Unexplained hoarseness Patient is child Cervical lymphadenopathy Rapid enlarging ,painless thyroid mass within weeks. Features raising suspecting thyroid medullary carcinoma. B) If normal TFTs without one of the previous criteria - routine referral to specialist clinic.

C) If thyroid function tests is abnormal non urgent referral to specialist clinic. The British Thyroid society do not recommend investigations beyond thyroid function tests such as thyroid sonography at general practice as it may cause delay in cancer diagnosis (Perros et al,2014). The specialist clinics : Thyroid nodule clinic. General surgery clinic. Nuclear medicine clinic. Endocrine clinic. Close loop communication between different members of the management team is necessary for the benefit of the patient (Perros et al,2014)..

D) The following cases may followed at General practice (Bailey et al,2018) : Patient with long standing thyroid nodule without any change in size. Patient with thyroid nodule but without any risk for malignancy. Patient with thyroid nodule <1cm. Follow up at General practice (Bailey et al,2018) : Highly suspicious nodules repeat ultrasonography within 6–12 months. Low-risk and intermediate- risk nodules within 12–24 months..

Knox, 2013.. Palpable nodule discovered by patient or physician History, examination, TSH suppressed Radionuclide thyroid scan to rule out hyper functioning nodule Radioiodine ablation or surgical excision if hyper functioning Incidental nodule discovered on imaging, not clinically palpable TSH measurernent, ultrasonography TSH normal or high Solitary solid nodule > 1 cm orc 1 cm vvith risk factors Ultrasound-guided Multiple nodules Apparent palpable nodule not demonstrated on imaging Clinical follovv-up 1 cr-n S 1 cm Malignant or suspicious for malignancy Thyroid surgery fine-needle aspiration Benign Follovv-up in six months (earlier if symptomatic) Clinical f0110\N-up Unsatisfactory specimen Fine-needle aspiration repeated in one to four weeks to mirror structure Of other endpoints size for biopsy vvith rnu/tip/e nodules not clear/y established..

Conclusion. Management of incidental thyroid nodule in general practice is a real challenge. Proper history and examination are crucial in general practice. Based on findings of the history and examination , management plan will be designed. Only nodules with benign cytology or no risks for malignancy be allowed to follow at general practice. Proper communication between the general practitioner and other members of the management team is necessary for the benefit of the patient..

References:. Ahuja, A.T., Evans, R.M., King, A.D. and van Hasselt, C.A. eds., 2003. Imaging of head and neck cancer. Cambridge University Press. Bailey, S. and Wallwork , B., 2018. Differentiating between benign and malignant thyroid nodules:'An evidence-based approach in general practice'. Australian journal of general practice, 47(11), pp.770-774. Baskin, H.J., 2004. Ultrasound-guided fine-needle aspiration biopsy of thyroid nodules and multinodular goiters . Endocrine Practice, 10(3), pp.242-245. Boelaert , K., Horacek , J., Holder, R.L., Watkinson, J.C., Sheppard, M.C. and Franklyn, J.A., 2006. Serum thyrotropin concentration as a novel predictor of malignancy in thyroid nodules investigated by fine-needle aspiration. The Journal of Clinical Endocrinology & Metabolism, 91(11), pp.4295-4301. Dean, D.S. and Gharib, H., 2008. Epidemiology of thyroid nodules. Best practice & research Clinical endocrinology & metabolism, 22(6), pp.901-911. Hoang, J.K., Langer, J.E., Middleton, W.D., Wu, C.C., Hammers, L.W., Cronan , J.J., Tessler, F.N., Grant, E.G. and Berland, L.L., 2015. Managing incidental thyroid nodules detected on imaging: white paper of the ACR Incidental Thyroid Findings Committee. Journal of the American College of Radiology, 12(2), pp.143-150. Kroeker , T.R., le Nobel, G., Merdad , M. and Freeman, J.L., 2014. Outcomes of incidentally discovered thyroid nodules referred to a high‐volume head and neck surgeon. Head & neck, 36(1), pp.126-129. Perros , P., Boelaert , K., Colley, S., Evans, C., Evans, R.M., Gerrard Ba, G., Gilbert, J., Harrison, B., Johnson, S.J., Giles, T.E. and Moss, L., 2014. Guidelines for the management of thyroid cancer. Clinical endocrinology, 81, pp.1-122. Yoon, D.Y., Chang, S.K., Choi, C.S., Yun, E.J., Seo , Y.L., Nam, E.S., Cho, S.J., Rho, Y.S. and Ahn , H.Y., 2008. The prevalence and significance of incidental thyroid nodules identified on computed tomography. Journal of computer assisted tomography, 32(5), pp.810-815. Knox, M.A., 2013. Thyroid nodules. American Family Physician, 88(3), pp.193-196..