Preoperative Evaluation Lateral compartment lymph nodes are easier to detect and are amenable to FNA Central compartment lymph nodes are much more difficult to detect and FNA (Tg washout testing is compromised)
Surgical Levels of the Neck See insert in back of syllabus. Som et al, AJR 174:837 2003
Surgical Compartments of the Neck Compartment I Submandibular to the hyoid bone Compartments II, III, IV From the vascular bundle deep to the SCM Division by hyoid and cricoid Compartment V Posterior to the SCM Compartment VI The central compartment
Cervical Lymph Nodes Approximately 300 lymph nodes in the normal neck. Typically can identify 6 20 nodes by ultrasound. Nodes are more prominent following infections, mononucleosis, dental procedures and in Hashimoto s thyroiditis.
Differentiated Thyroid Cancer 63,000 New cases of DTC in 2014 1,890 Deaths predicted in 2014 Mortality essentially unchanged over past 30 years Unproved assumption: Early detection and treatment of cervical metastases will affect mortality Mortality versus Morbidity
Preoperative Imaging WDTC clinically involves lymph nodes in approximately 20% of patients. (Micrometastases in up to 90%) Pre-op US identifies suspicious Lateral neck nodes in approximately 14% of cases. Surgical management is altered in the presence of lateral neck metastases Near total Thyroidectomy Central Neck Dissection! (ATA Guidelines 2009) Lateral Neck Dissection Kouvaraki, Surgery 2003 134:946; Stulak, Arch Surg 2006 141:489
Preoperative Imaging Alternatives Ultrasound evaluation is uniquely operator dependent Sensitivity of CT, MRI and PET is less Ultrasound versus CT Characteristics of benign/suspicious nodules Contrast interference with RAI ablation Expense and time Visualization behind trachea and TE groove
RECOMMENDATION 6 Thyroid sonography with survey of the cervical lymph nodes should be performed in all patients with known or suspected thyroid nodules. (Strong recommendation, High-quality evidence) Haugen et al Thyroid 2016
And, if pre-op US NOT performed... 17 patients underwent reoperation for thyroid cancer MD Anderson <6months after initial surgery PRE-OP US would have prevented 70% or the reops!!! Kouvaraki Surgery 2004 136:1183
Role for Preoperative Ultrasound Nodal Evaluation 560 patients underwent thyroidectomy and modified neck dissection US neg LNs 455 pts Recurrence rate US Neg 3.1% US + LNs 105 pts US Pos 24.8% Recurrences occurred significantly more often if ultrasound demonstrated abnormal nodes preoperatively 1 1 Ito, World J Surg 2005; 2 Ito, World J Surg 2004
Prophylactic lateral neck dissection does NOT improve recurrence free survival for patients with preoperative US negative for lymph nodes 1 Does lateral neck dissection alter the outcome for preoperative US positive for lymph nodes? 1 Ito, World J Surg 2004
For macroscopic lateral lymph node metastases, modified neck dissection at time of initial thyroidectomy improves survival Noguchi, Arch Surg, 1998 133 276-280
Management Guidelines for Patients with Thyroid Nodules and Differentiated Thyroid Cancer 2015 RECOMMENDATION 32 A) Preoperative neck US for cervical (central and especially lateral neck compartments) lymph nodes is recommended for all patients undergoing thyroidectomy for malignant or suspicious for malignancy cytologic or molecular findings. (Strong recommendation, Moderate-quality evidence) RECOMMENDATION 33 A) Preoperative use of cross-sectional imaging studies (CT, MRI) with intravenous contrast is recommended as an adjunct to ultrasound for patients with clinical suspicion for advanced disease including invasive primary tumor, or clinically apparent multiple or bulky lymph node involvement. (Strong recommendation, lowquality evidence) Haugen et al Thyroid 2016
Pre-op evaluation of central compartment Carotid Thyroid nodule Metastatic paratrachael lymph node
Preoperative Evaluation of Lateral Compartment 48yo female with cystic nodule right lobe (N) and lymph node in neck (LN) FNA cytology of nodule and lymph node negative LN C N Needle washout from lymph node Tg=24.3ng/ml
Post-operative Ultrasound Evaluation for the Surveillance of Patients with Low Risk (Stage I and II) Thyroid Cancer
Tests Used in Post-0perative Thyroid Cancer Surveillance Thyroglobulin 131 I or 123 I Whole Body Scan Ultrasound
Detection of LN metastases WBS vs. Neck US Sensitivity (%) 100 90 80 70 60 50 40 30 20 10 0 WBS US Frasoldati Pacini Torlontano Frasoldati et al, Cancer 2003; Pacini et al, J Clin Endocrinol Metab 2003; Torlontano et al, J Clin Endocrinol Metab 2004
Diagnosis of Recurrent DTC in 51 of 494 Patients 131 I Whole Body Scan 23 (45%) Tg > 2ng/ml (off T4 therapy) 29 (57%) Tg detectable 34 (67%) Ultrasound 48 (94%) Frasoldati, et al; Cancer 2003
Limitations of Whole Body Scans Morbidity of thyroid withdrawal Expense Poor sensitivity (60-75%) lack of transmembrane sodium iodide symporter expression (especially with BRAF/RAS mutation) Iodine contamination Insufficient TSH stimulation Stunning Potential for causing growth? Withdrawal versus Thyrogen
RECOMMENDATION 65 A) Following surgery, cervical US to evaluate the thyroid bed and central and lateral cervical nodal compartments should be performed at 6 12 months and then periodically, depending on the patient s risk for recurrent disease and Tg status. (Strong recommendation, Moderatequality evidence) Haugen et al Thyroid 2016
Does US change surgery? Imaging of nonpalpable nodes MD Anderson Mayo 100 87 Percent (%) 80 60 40 20 14 14 68 0 Initial Surgery Reoperation Kouvaraki, Surgery 2003 134:946; Stulak, Arch Surg 2006 141:489
Where do we look for metastatic lymph nodes?
Locations of PTC nodal recurrences Ipsilateral ONLY, 12% skip metastases Central and bilateral, 13% Bilateral only, 1% 87% involve Central LNs Central ONLY, 22% Central and ipsilateral, 52% Leboulleux J Clin Endocrinol Metab 2005
Post-operative Ultrasound Evaluation Both the central compartment and the lateral compartments of the neck are easily surveyed with US in the post-op thyroid cancer patient FNA using US guidance allows both cytology and analysis for thyroglobulin without regard to thyroglobulin antibody
Post-operative Neck
Characteristics of Benign Lymph Nodes Flattened or oval shape (AP/T <0.5) Echogenic (hilar) line Hilar vascular flow on Doppler Size varies with compartment and is less important than morphology. Border definition also less important.
The Hilar Line A normal node can be split down the central hilum. Hilum contains fat and vessels A normal hilar line can be thin or thick, and can be central or eccentric/diagonal. The presence of a hilar line is reassuring.
Normal lymph node- hilus
Normal Lymph Nodes
Normal Node with Broad Central Hilum
Normal Lymph Node
Normal Lymph Node Normal hilar blood flow
Node Shape Variations Central Compartment Paratracheal nodes Post surgical neck Loss of usual tissue planes Hashimoto s Matted Inflammatory
Paratracheal Nodes Hashimoto s Thyroiditis
Hashimoto s Thyroiditis
Node Size Variations Is there an absolute size limitation? Compartments III, IV 5 mm AP (?) NO!! Compartment II 8 10 mm AP (?) NO!!! Role for repeat evaluation over time Reactive nodes vary over time without progressive growth.
Large Benign Node - Compartment 2
Compartment 3 - Benign
Compartment 3 Benign 6 months later
Compartment 3 Benign 6 months later 10/07 4/08
Papillary Carcinoma Small round nodes - Benign
Papillary Carcinoma Small round nodes - Benign
Characteristics of Metastatic Lymph Nodes Absent echogenic (hilar) line Rounded appearance AP/T>.5 (transverse view) Jugular displacement Calcifications Cystic necrosis Chaotic vascularization
Characteristics of Malignant Nodes Sensitivity Specificity Disordered vascularity 86% 82% Microcalcifications 45% 100% Cystic Degeneration 11% 100% Absence of Hilar Line 95% 20% Hypoechoic Echotexture 39% 18% From Susan Mandel 2008 Leboulleux JCEM 2007 Ahuja, Clinical Radiology 2001
Malignant Node: AP/T >0.5
Malignant Nodes AP/TV >0.5
Malignant Node
Jugular Displacement Calcification
Jugular Displacement
Enhancement Cystic Necrosis
Heterogeneous Echogenicity Calcifications
Papillary Carcinoma Tall Cell Calcified Node
Papillary Carcinoma Node Chaotic Vascularity
Metastatic Papillary Carcinoma Central Lateral
Lymph node in central compartment
Compartment 3 - Malignant
Central Compartment Node hypoechoic
Malignant Node hyperechoic
Malignant Node Anaplastic CA
Malignant Node Hurthle Cell CA
Chaotic vascularization
What do we do when US detects an abnormal LN? RECOMMENDATION 65 B) If a positive result would change management, ultrasonographically suspicious lymph nodes > 8-10 mm (see Recommendation 71) in the smallest diameter should be biopsied for cytology with Tg measurement in the needle washout fluid. (Strong recommendation, Low-quality evidence) Haugen et al Thyroid 2016
Detection of malignancy in 40 LNs after US guided FNA Cyto FNA Tg Sensitivity (%) 100 90 80 70 60 50 40 30 20 10 0 100 100 86 81 TG Ab+ TG Ab- Patients' Ab status Boi, J Clin Endocrinol Metab, 2006
143 Consecutive Patients with Stage I and II Papillary Cancer June 2003-November 2004 41 patients had 1 or more suspicious lymph nodes and underwent UG-FNA. 14 patients had positive cytology and/or Tg washout. Baskin, Thyroid 14:11:2004
Recurrent Cancer Patients Age/sex Years Tg Tg AB Cytology FNA-Tg 22 M 1 14.2 - + 39.9 50 M 13 <0.3 + + 24.9 53 F 12 <0.3 - + 19.8 51 F 20 <0.3 - + 10.5 36 M 2 <0.3 + + 67.5 40 M 7 19. - - 500 52 M 5 1.8 - - 443 54M 4 8 - - 87.5 48F 1 <0.3 + - 24.3 32F 18 0.8 - + 10,936 43F 2 0.6 - + 6.6 57F 13 <0.3 - - 237 71F 15 1.3 - + 1.5 54F 36 11.5 - + 2
The challenge of minimal residual/recurrent disease right IJ CA left IJ CA
Recommendation 65 C) Suspicious lymph nodes less than 8-10 mm in smallest diameter may be followed without biopsy with consideration for FNA or intervention if there is growth or if the node threatens vital structures. (Weak recommendation, Low-quality evidence) Haugen et al Thyroid 2016
Differential Diagnosis of Cervical Lymph Nodes Benign Reactive Thyroid Cancers Cervical Lymphoma Chronic Lymphocytic Leukemia Metastases from other Cancers Sarcoid
Cervical Lymphoma
Cervical Lymphoma
Chronic Lymphocytic Leukemia
Chronic Lymphocytic Leukemia
Breast metastases to Cervical Compartment IV
Breast Cancer Compartment IV
Sarcoid Cervical Adenopathy NOT vascular
Role of cross sectional imaging in setting of rising thyroglobulin: Neck MRI or CT with contrast for clinically occult nodes Retropharynx Parapharyngeal space Low cervical lymph nodes Mediastinum Consider in patients with prior metastatic LNs in anterior cervical compartments Kaplan, Mandel J Neuroradiol, 2009
History of thyroid cancer, rising thyroglobulin Left retropharyngeal lymph node CT guided FNA Kaplan, Mandel J Neuroradiol, 2009
Conclusions Lymph node mets (esp micromets) are extremely common in PTC Preoperative recognition of CLINICALLY apparent lymph nodes with ultrasound changes the surgical approach and reduces the chance of reoperation Malignant nodes are often rounded (AP/T >0.5) with loss of visible hilum.
Conclusions Nodes with internal calcification or cystic changes are highly suspicious for malignancy Cytology and Tg needle washout are collected from LN FNA procedures Tg needle washout remains valid in presence of Tg Ab
Conclusions CT or MRI can be used preoperatively to define tissue planes in bulky or potentially invasive disease CT or MRI can be used postoperatively in patients with persistent Tg to look for retropharygeal or mediastinal nodes