Thyroid Case 2

A 66 year-old woman had a thyroid nodule incidentally discovered during magnetic resonance imaging (MRI) of the neck to evaluate neck pain. A thyroid ultrasound revealed a solitary 1.1 cm hypoechoic, solid, well-circumscribed nodule with Grade 4 vascularity on Doppler flow and no calcifications. No abnormal lymph nodes were observed. Her thyroid-stimulating hormone (TSH) level was 1.9 mIU/L (normal, 0.5-5.7 mIU/L). Fine needle aspiratory biopsy was performed, and cytology was positive for papillary thyroid carcinoma. She underwent a total thyroidectomy, and the histopathology showed a 0.8 cm classical variant of papillary thyroid carcinoma (PTC), with no evidence of capsular or lymphovascular invasion. Three lymph nodes were negative for carcinoma.

She presents for an initial consultation four weeks after surgery. She has no post-operative complaints and is taking levothyroxine 100 mg daily in the morning. On physical examination, she appears well. Her heart rate is 70 beats/minute, and her blood pressure (BP) is 136/74 mm Hg. She reports feeling fatigued without other symptoms. She has a healing thyroidectomy scar, and palpation of the neck reveals no suspicious masses or lymph nodes.

Question 1

In addition to providing levothyroxine replacement, which of the following is the next best step in this patient's treatment?

A. Increase her medication to levothyroxine 200 mg daily and follow up in three months
B. Assessment of TSH and thyroglobulin concentrations
C. Testing of the tumor to detect the BRAF V600E mutation
D. Positron emission tomography (PET)/computerized tomography (CT) scan
E. Repeat operation for Level IV lymph node exploration
Incorrect!
Correct!
Correct Answer
B. Assessment of TSH and thyroglobulin concentrations

Thyroid cancer is the most common endocrine malignancy, and data show the incidence has risen substantially. The most common subtype is papillary thyroid cancer, comprising 80-85% of cases, and the majority of the rise in thyroid cancer cases is due to the small (This patient has a solitary papillary thyroid microcarcinoma (See Fig. 1aProposed modification, not present in the original 2009 initial risk stratification system. Reprinted with permission from Haugen BR, Alexander EK, Bible KC, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2016;26:1-133.To help further assess the patient's risk of persistent disease, thyroglobulin (Tg) measurement (either TSH stimulated or nonstimulated) 3-4 weeks post-operatively is recommended (option B). In low risk papillary thyroid cancer patients, such as the one in this case, a thyroglobulin concentration 2 ng/dL.Increase in her levothyroxine dosing (option A) may be appropriate after assessment of TSH, but would not be the best course of action at this time.

Her fatigue cannot reliably be attributed to her thyroid hormone status without assessment of her current TSH concentration.Assessment of the tumor specimen for a BRAFV600E somatic mutation (option C) is not routinely recommended. For intrathyroidal papillary microcarcinoma, the presence of BRAFV600E does not affect the low risk classification. Although BRAF V600E positive papillary thyroid cancers are higher risk in some cases, there are no recommendations to manage thyroid cancer any differently based on BRAF status.PET-CT scanning (option D) is not indicated because her low-risk papillary thyroid carcinomas (PTC) makes it highly unlikely that she has aggressive metastatic disease that would be detected on further imaging.A second operation to explore and remove central neck (level VI) lymph nodes for this patient with low risk papillary thyroid cancer is not indicated (option E).

Removal of lymph nodes is indicated if there is evidence of lymph node metastases in that area. The role of a prophylactic (without clinical evidence of disease) dissection level VI lymph node remains controversial, given uncertainty regarding any survival benefit in the setting of demonstrable increases in surgical risks (such as hypoparathyroidism and vocal cord paralysis). Prophylactic level VI lymph node dissection should be considered when there is more advanced local disease (T3 or T4) or clinically involved lateral neck nodes.

Thyroid cancer is the most common endocrine malignancy, and data show the incidence has risen substantially. The most common subtype is papillary thyroid cancer, comprising 80-85% of cases, and the majority of the rise in thyroid cancer cases is due to the small (This patient has a solitary papillary thyroid microcarcinoma (See Fig. 1aProposed modification, not present in the original 2009 initial risk stratification system. Reprinted with permission from Haugen BR, Alexander EK, Bible KC, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid. 2016;26:1-133.To help further assess the patient's risk of persistent disease, thyroglobulin (Tg) measurement (either TSH stimulated or nonstimulated) 3-4 weeks post-operatively is recommended (option B). In low risk papillary thyroid cancer patients, such as the one in this case, a thyroglobulin concentration 2 ng/dL.Increase in her levothyroxine dosing (option A) may be appropriate after assessment of TSH, but would not be the best course of action at this time.

Her fatigue cannot reliably be attributed to her thyroid hormone status without assessment of her current TSH concentration.Assessment of the tumor specimen for a BRAFV600E somatic mutation (option C) is not routinely recommended. For intrathyroidal papillary microcarcinoma, the presence of BRAFV600E does not affect the low risk classification. Although BRAF V600E positive papillary thyroid cancers are higher risk in some cases, there are no recommendations to manage thyroid cancer any differently based on BRAF status.PET-CT scanning (option D) is not indicated because her low-risk papillary thyroid carcinomas (PTC) makes it highly unlikely that she has aggressive metastatic disease that would be detected on further imaging.A second operation to explore and remove central neck (level VI) lymph nodes for this patient with low risk papillary thyroid cancer is not indicated (option E).

Removal of lymph nodes is indicated if there is evidence of lymph node metastases in that area. The role of a prophylactic (without clinical evidence of disease) dissection level VI lymph node remains controversial, given uncertainty regarding any survival benefit in the setting of demonstrable increases in surgical risks (such as hypoparathyroidism and vocal cord paralysis). Prophylactic level VI lymph node dissection should be considered when there is more advanced local disease (T3 or T4) or clinically involved lateral neck nodes.