Devita, Hellman, and Rosenberg's Cancer

LWBK1006-25 LWW-Govindan-Review December 12, 2011 19:21

358 DeVita, Hellman, and Rosenberg’s CANCER: Principles and Practice of Oncology Review

ANSWERS

Answer 25.1. The answer is A.

Total thyroidectomy alone and without neck dissection is the appropri-

ate initial management in this patient with well-differentiated papillary

thyroid carcinoma, especially in the absence of palpable lymph nodes or

abnormal lymph nodes on ultrasound.

Answer 25.2. The answer is A.

The patient has microscopic papillary thyroid carcinoma, typically

defined as a solitary tumor, less than 1.0 to 1.5 cm, with the absence of

lymph node involvement. There is no need for further surgical resection

beyond lobectomy and intraoperative examination of the contralateral

lobe in this case. Thyroid hormone replacement might be needed postop-

eratively.

Answer 25.3. The answer is C.

The appropriate management is complete lobectomy and isthmusectomy,

to be followed by total thyroidectomy later if malignancy is confirmed.

This is especially true in cases of suspected follicular carcinoma because

FNA does not distinguish benign from malignant follicular pathology.

Intraoperative frozen section would not be of great help in this regard. The

finding of vascular or capsular invasion on final pathologic examination

will help to determine the diagnosis.

Answer 25.4. The answer is B.

Patients with thyroid carcinoma are typically followed up with TG levels

and iodine scan. TG levels are very sensitive, particularly when TSH is

suppressed. In the face of negative iodine scan, and particularly when TG

level is greater than 10, distant metastatic disease is suspected. PET scan

is most helpful in these cases where thyroid cancer dedifferentiates and

loses iodine uptake.

Answer 25.5. The answer is A.

MTC is a neuroendocrine tumor. The hallmark is elevated serum cal-

citonin, which is produced by the parafollicular cells (thyroid C cells).

CEA is another tumor marker of this disease, but less specific because

it can be elevated in other malignancies. MTC can be part of MEN2A,

which includes pheochromocytoma, and it must be ruled out before any

surgery. Germ line mutation causes familial non-MEN MTC, MEN2A,

and MEN2B. RET proto-oncogene has become a standard test in the

evaluation of newly diagnosed MTC.

Answer 25.6. The answer is B.

Radioactive iodine ablation is indicated in patients with high-risk features

despite complete excision. Male patients aged more than 40 years are