A 33-year-old woman comes to the office for follow-up of a thyroid nodule that was discovered incidentally on a routine physical examination 3 weeks ago. The patient feels well and has experienced no weight changes, temperature intolerance, or menstrual irregularities. Medical history is notable for primary hypothyroidism treated with levothyroxine. Family history is notable for hypertension and hypothyroidism in her mother, but the patient has no relatives with a history of thyroid cancer. TSH is normal. Neck ultrasound reveals a 2.0-cm hypoechoic nodule in the right lobe of her thyroid without any enlarged lymph nodes. Fine-needle aspiration biopsy reveals large cells with ground glass cytoplasm, and pale nuclei containing inclusion bodies and central grooving consistent with papillary thyroid cancer. Which of the following is the best next step in management of this patient?

Question

A 33-year-old woman comes to the office for follow-up of a thyroid nodule that was discovered incidentally on a routine physical examination 3 weeks ago.  The patient feels well and has experienced no weight changes, temperature intolerance, or menstrual irregularities.  Medical history is notable for primary hypothyroidism treated with levothyroxine.  Family history is notable for hypertension and hypothyroidism in her mother, but the patient has no relatives with a history of thyroid cancer.  TSH is normal.  Neck ultrasound reveals a 2.0-cm hypoechoic nodule in the right lobe of her thyroid without any enlarged lymph nodes.  Fine-needle aspiration biopsy reveals large cells with ground glass cytoplasm, and pale nuclei containing inclusion bodies and central grooving consistent with papillary thyroid cancer.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

Surgical resection is the primary treatment for papillary thyroid cancer. The extent of surgery depends on the tumor size, extrathyroidal invasion, patient age, and lymph node involvement. Small tumors (<1-2 cm) without evidence of lymph node involvement or contralateral thyroid abnormalities can usually be managed with partial thyroidectomy/lobectomy, whereas larger tumors usually warrant total thyroidectomy. In addition, regional lymph node or central compartment lymph node dissection is usually performed for papillary cancer with lymph node metastasis or extrathyroidal invasion. Following surgery, adjuvant therapy with radioiodine ablation is warranted for patients with increased risk of tumor recurrence (eg, large tumors, extrathyroidal invasion, lymph node metastasis, incomplete resection) (Choice D). TSH can stimulate growth of occult residual or metastatic disease. For this reason, patients at increased risk of recurrence should also receive adequate doses of thyroid replacement to suppress TSH secretion. (Choice A) Thyroid peroxidase (TPO) antibodies are a marker for chronic lymphocytic (Hashimoto) thyroiditis. TPO antibodies are useful in the initial evaluation of hypothyroidism and diffuse goiter but have no utility in evaluation of papillary thyroid cancer. (Choice B) Mutations of several genes (eg, BRAF, RET) are common in papillary thyroid cancer. Genetic mutation profiling may be performed when the cytology results from fine-needle aspiration biopsy are indeterminate but are not needed if cytology confirms papillary cancer. (Choice C) Calcitonin is a marker for medullary thyroid cancer, which arises from the parafollicular C cells of the thyroid gland. Papillary and follicular cancers arise from thyroid epithelial cells. (Choice F) Thyroid scintigraphy is performed in the initial evaluation of thyroid nodules in patients with subnormal TSH levels. A hyperfunctioning ("hot") nodule with increased uptake of the radiomarker is less likely to be malignant than a hypofunctioning ("cold") nodule. Educational objective: Surgical resection is the primary treatment modality for papillary thyroid carcinoma. Postoperative adjuvant therapies for patients at increased risk of recurrence include radioiodine ablation and suppressive doses of thyroid hormone. References: 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer: the American Thyroid Association guidelines task force on thyroid nodules and differentiated thyroid cancer. (http://www.ncbi.nlm.nih.gov/pubmed/26462967)

A 33-Year-Old Woman Comes to the Office for Follow-Up of a Thyroid