thyroid stuff cytopathology & pathology ryan orosco sept 2013
TRANSCRIPT
Thyroid StuffCytopathology & Pathology
Ryan OroscoSept 2013
Objective
• Understand benefits of FNA• Learn an algorithmic approach to FNA
cytopathology• Be able to name and identify key cytologic
features of papillary thyroid cancer
Benign Causes of Thyroid Nodules
• Adenomatous nodule• Colloid nodule• Follicular adenoma• Simple thyroid cyst• Graves disease• Chronic lymphocytic thyroiditis (Hashimoto’s)• Focal subacute thyroiditis• Developmental conditions
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Benefits of Using FNA to Evaluate Thyroid Nodules
• Reduces number of patients requiring surgery by 50%
• Increases the yield of thyroid malignancies at thyroidectomy by 2-3x
• Decreases the cost of managing thyroid nodules by 25%
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Diagnostic Categories• Nondiagnostic – occurs in 10-30% of cases• Benign – about 70% of the time
– Low false negative rate (1-3%) gives you confidence to follow non-surgically
• Malignant – about 10-20% of the time– Low false negative rate (1-3%) gives you confidence to follow non-
surgically• Suspicious for Malignancy – about 60-75% risk for malignancy
– Usually managed with total thyroidectomy given high risk
• Suspicious for Follicular Neoplasm – 10-30% risk for malignancy– Usually managed with lobectomy
• Atypia of Undetermined Significance – should be less than 10% of FNAs. Risk of malignancy 5-15%.– Usually managed with repeat FNA in 3 months
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Sensitivity/specificity depends on how indeterminate specimens and suspicious groups of lesions are handled, skill of the person doing the u/s and FNA, cytopathologist expertise
False neg and false pos are usually less than 1% in most series
About 18% of pts who get a FNA are treated surgically
Sensitivity/specificity depends on how indeterminate specimens and suspicious groups of lesions are handled, skill of the person doing the u/s and FNA, cytopathologist expertise
False neg and false pos are usually less than 1% in most series
About 18% of pts who get a FNA are treated surgically
The Spectrum of Thyroid Cancer• The good: well-differentiated• The bad: poorly differentiated• The ugly: undifferentiated (anaplastic)
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Cystic
Inflammatory & LymphomaInflammatory & Lymphoma
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Colloid Predominant
Epithelium-PredominantEpithelium-Predominant
Epithelium-PredominantEpithelium-Predominant
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Epithelium-Predominant – Hurthle cellEpithelium-Predominant – Hurthle cell
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Epithelium-Predominant – PTCEpithelium-Predominant – PTCFeatures of PTC
Diagnostic:• Hypercellular• Monolayered sheets with crowding
and disorganization• Enlarged oval nuclei• Fine, evenly dispersed chromatin• Nuclear grooves• Nuclear pseudoinclusions
Associated:• Dense squamoid cytoplasm• Multinucleated giant cells• Densely staining “rope” colloid• Psammoma bodies
Features of PTC
Diagnostic:• Hypercellular• Monolayered sheets with crowding
and disorganization• Enlarged oval nuclei• Fine, evenly dispersed chromatin• Nuclear grooves• Nuclear pseudoinclusions
Associated:• Dense squamoid cytoplasm• Multinucleated giant cells• Densely staining “rope” colloid• Psammoma bodies
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Epithelium-Predominant – PTCEpithelium-Predominant – PTC
Thyroid Cytopathology, Faquin and Clark, Springer 2010
Thyroid Cytopathology, Faquin and Clark, Springer 2010