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EndocrinE  ` endocrine—PAthology                            EndocrinE  ` endocrine—PAthology          SEcTion iii      343




                  Thyroid cancer         Typically diagnosed with fine needle aspiration; treated with thyroidectomy. Complications of
                                          surgery include hypocalcemia (due to removal of parathyroid glands), transection of recurrent
                                          laryngeal nerve during ligation of inferior thyroid artery (leads to dysphagia and dysphonia
                                          [hoarseness]), and injury to the external branch of the superior laryngeal nerve during ligation of
                                          superior thyroid vascular pedicle (may lead to loss of tenor usually noticeable in professional voice
                                          users).
                   Papillary carcinoma   Most common, excellent prognosis. Empty-appearing nuclei with central clearing (“Orphan
                                          Annie” eyes)  A , psamMoma bodies, nuclear grooves (Papi and Moma adopted Orphan Annie).
                    A
                                           risk with RET/PTC rearrangements and BRAF mutations, childhood irradiation.
                                         Papillary carcinoma: most Prevalent, Palpable lymph nodes. Good prognosis.








                   Follicular carcinoma  Good prognosis. Invades thyroid capsule and vasculature (unlike follicular adenoma), uniform
                                          follicles; hematogenous spread is common. Associated with RAS mutation and PAX8-PPAR-γ
                                          translocations.
                   Medullary carcinoma   From parafollicular “C cells”; produces calcitonin, sheets of polygonal cells in an amyloid stroma
                                          B  (stains with Congo red). Associated with MEN 2A and 2B (RET mutations).
                    B











                   Undifferentiated/     Older patients; presents with rapidly enlarging neck mass Ž compressive symptoms (eg, dyspnea,
                    anaplastic carcinoma  dysphagia, hoarseness); very poor prognosis. Associated with TP53 mutation.



                  Diagnosing
                  parathyroid disease
                                                 250
                                                             2° hyperparathyroidism     1° hyperparathyroidism
                                                                          2+
                                                         (vitamin D deficiency, ↓ Ca intake,  (hyperplasia, adenoma,
                                                             chronic kidney disease)        carcinoma)
                                                  50
                                                 PTH (pg/mL)            Normal




                                                  10

                                                      1° hypoparathyroidism               PTH-independent
                                                       (surgical resection,                hypercalcemia
                                                                                          2+
                                                         autoimmune)                (excess Ca  intake, cancer, ↑ vitamin D)
                                                   2
                                                    4       6       8      10      12      14     16      18      20
                                                                                 2+
                                                                                Ca  (mg/dL)












          FAS1_2019_08-Endocrine.indd   343                                                                             11/7/19   4:30 PM
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