Thyroid Nodule Evaluating the patient with a thyroid nodule and some management options. Miguel V. Valdez PA C Disclosure Nothing to disclose. Learning Objectives Examination of thyroid gland Options for evaluating thyroid nodules Incidence of malignancy Some management options 1
Anatomy Anatomy Anatomy 2
The Exam The Exam Epidemiology Most nodules found on exams for other reasons 5% of adult population 30% of adults by ultrasound Adults > 60: 50%-60% chance of having a nodule 3
Epidemiology Increased risk Female Elderly History of radiation exposure Endemic iodine deficiency Epidemiology Thyroid Pathology: New thyroid nodules: 300,000/year Large majority are benign Wide range of pathology Benign cyst to lethal malignancy Epidemiology Solitary nodule Incidence of malignancy: 10 30% Most patients do very well Well differentiated thyroid carcinoma (WDTC) Papillary 78% Follicular 13% Medullary Anaplastic 4
Chief Justice Rehnquist Thyroid Nodule: Differential Diagnosis Colloid Nodule -- Multinodular Goiter Adenoma Cyst Focal Thyroiditis Metastasis to thyroid Kidney, Breast Laryngeal, esophageal tumor Non-thyroid: Lymph node Thyroglossal duct cyst Laryngocele Prominent or tortuous vessel Degree of Clinical Concern for Carcinoma Less Concern Stable exam Evidence of functional disorder Hashimoto s Toxic nodule Multinodular gland without dominant nodule More Concern Age < 20, > 60 Male Rapid growth Family history of thyroid carcinoma Hard fixed lesion Lymphadenopathy Hoarseness/dysphagia Size > 4 cm Cyst recurrence after aspiration History of radiation therapy 5
History of Low-Dose Ionizing Radiation Tonsil/thymus, acne Hodgkin s, scatter from breast Rx Chernobyl 20-30% develop nodules 30-50% chance of cancer in patients presenting with such a history Thyroid Nodule: Laboratory Work-Up Serum Testing TSH Hyper/hypothyroidism rarely seen in malignancy Full TFTs if TSH abnormal Work up functional disorder Hashimoto s Toxic Nodule Antibody studies Malignancy: No effective markers Calcitonin: not routine Thyroglobulin No diagnostic significance Useful in long-term follow-up in patients with thyroid carcinoma Hashimoto s Thyroiditis Common cause of hypothyroidism More frequent in females Autoimmune lymphocytic hypothryroidism Small firm lobes may be mistaken as nodule In general, avoid FNA in Hashimoto s False positive tests are more frequent (microfollicles, Hurthle cells) Must monitor for lymphoma (long term) 6
Toxic Nodule Very low incidence of malignancy High risk of microfollicle false-positive FNA Finding low TSH allows proper workup May avoid a confusing FNA Multinodular Goiter Multifocal hyperplasia Nodules may undergo cystic degeneration Dominant nodule is considered as a solitary thyroid nodule in terms of malignancy risk Imaging CXR: Not routine CT Does not differentiate benign or malignant Pre-op evaluation in specific cases Cervical lymphadenopathy Substernal extension Tracheal deviation Contrast Iodine-based, affects other RAI testing MRI No radiation, no iodine Effective for residual, recurrent, metastatic disease PET Sensitivity 65%, Specificity 95%, poor for lung mets 7
Cervical Lymph Nodes Imaging Thyroid scan (Tc 99, I 123 ) Assesses thyroid function only Low sensitivity, specificity for malignancy Study of 5,000 patients 84% hypo functional (cold) CA found: 16% of cold nodules and 5% of hot nodules When to scan? Nodule with clinical picture of Hashimoto s Avoid false-positive FNA Hyperthyroid patient Toxic nodule, Grave s Imaging Ultrasound Does not distinguish between benign versus malignant; findings suggestive of malignancy: microcalcifications, solid, hypervascularity, size >2 cm 70% of solitary nodules are solid 20% malignant 30% cystic/mixed 10% malignant Operator-dependent Follow size of nodule Find other nodules Localize for FNA 8
Fine Needle Aspiration (FNA) Benign Macrofollicular/colloid nodule, thyroiditis Suspicious Follicular neoplasm (microfollicular pattern), Hurthle cell lesion Can not identify Follicular carcinoma Malignant Papillary, Anaplastic, Medullary Indeterminate (Non-diagnostic) Limitations Adequacy of specimen Accuracy of specimen Decreases % to O.R., Increases % Ca pathology Fine Needle Aspiration Management of Patients with Benign FNA s Conservative measures Repeat exams (4-6 months) Serial ultrasounds Repeat FNA 1-2 years, even if stable Suppressive therapy Surgery 9
FNA and Follicular Lesions Benign Colloid nodule Macrofollicular nodule Suspicious* Microfollicular pattern Hurthle cell Hypercellular Decreased colloid *Surgical excision recommended Management Medical suppression Goal: reduce/stabilize growth of nodule Does not distinguish benign and malignant tissue Outcome measures are controversial Dose/type Duration Definition of response (stable, decrease, disappear) Risks of long-term supplement Osteoporosis, Atrial fibrillation Cystic nodules typically do not respond Growth during suppression Surgery Surgical Management of WDTC Extent of Thyroidectomy Controversial Most data is retrospective Literature supports a variety of theories Main issue What is the best operation for a patient with a solitary nodule? 10
Surgical Management Hemithyroidectomy (lobe & isthmus) Anything less is inappropriate No lumpectomies Ideal for low-risk patient Young patients, 1cm, intrathyroidal, no mets Multiple studies No change in mortality Less risk to RLN, parathyroid Surgical Management Total thyroidectomy High incidence of multifocal disease (30-70%) Incidence of recurrence in opposite lobe Facilitates use of RAI Thyroglobulin levels for follow up Lower risk of complications Compared to re-operating High risk patients Controversies Morbidity Mortality Surgical Management Hypocalcemia is a potential risk/complication. Monitor Calcium level closely. Chvosteck s sign Trousseau s sign Circumoral or acral parasthesias Muscle spasms, pains,stiffness Replace calcium/vit D as needed. 11
Total Thyroid Specimen Surgical Management Neck Dissection Incidence of metastatic disease 50% papillary cancer Node/berry picking: inappropriate Studies can be confusing Patient with metastatic disease fare better Nodal metastases have few prognostic implications Clinically N 0 neck: no treatment Clinically positive neck Tracheoesophageal groove: remove central compartment Lateral neck: modified neck dissection Thyroid Pathology 12
Cervical Lymph Nodes 13
Radioactive Iodine Indications: High risk patient/tumor Distant metastases Residual disease/incomplete resection Purpose Ablate residual disease Improve thyroglobulin (Tg as tumor marker) Increase sensitivity of I 131 screening for recurrence Post Operative Supplement Thyroid Supplement Mandatory for total thyroidectomy Common practice to suppress TSH with subtotal surgery In Summary Most thyroid nodules are incidental finding If you don t look, you won t find them Most are benign Concern for the young and old Fine needle aspiration is the test of choice Surgery tends to be the preferred treatment 14
Thank You!! 15