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Chapter 15

Primary Care Otolaryngology

Treatment of papillary carcinoma is somewhat controversial. Historically,

a total thyroid

lobectomy

and

isthmectomy

have been used to treat

smaller papillary thyroid cancers (<1 cm). More recently, the trend has

been toward total thyroidectomy in patients with nodules containing pap-

illary thyroid cancers. Newer evidence from a study by Mazzaferri and

colleagues suggests that

total thyroidectomy,

when compared to subtotal,

may significantly decrease the local recurrence rate (18% versus 7%), and

ultimately the number of deaths (from 1.5% to 0.03%).

This study also

points out that patients treated with

radioactive iodine

and

thyroid hor-

mone suppression

have a decreased incidence of recurrence (3%), com-

pared to those treated with thyroid suppression alone (11%). However,

there was no difference in the number of deaths between these two

groups.

As mentioned earlier, if cervical metastatic thyroid cancer is present, a

modified or selective neck dissection

is indicated, depending on the

location of the disease. The greatest risks of thyroid surgery are hypopara-

thyroidism secondary to injury or removal of the parathyroid glands, and

recurrent laryngeal nerve injury,

which may result in hoarseness, short-

ness of breath, and reduced exercise tolerance.

Follicular Carcinoma

Approximately 15 percent of thyroid cancers is the follicular cell type. The

surgical specimen of all thyroid cancers must be sectioned completely to

determine if the tumor capsule and/or lymphatic and blood vessels are

invaded. The findings of capsular and/or lymphovascular invasion are

essential for diagnosis

and cannot be determined by a fine-needle aspi-

rate. Cytopathologically, the cells may also look fairly benign on fine-nee-

dle aspirate, so many specimens are interpreted as “consistent with adeno-

ma, cannot rule out follicular carcinoma.” This tumor metastasizes via the

blood. Two major types of follicular carcinoma are

microinvasive

and

macroinvasive.

A variant is Hürthle cell carcinoma, which is a more

aggressive form of follicular thyroid cancer and is marked by a high fre-

quency (75% or more) of Hürthle cells.

Like papillary carcinoma, follicular carcinoma has an affinity for radioac-

tive iodine. Since iodine is concentrated in normal thyroid tissue, an

attempt to remove all thyroid tissue allows a higher dose to be delivered to

Mazzaferri, E.T., et al. A vision for the surgical management of papillary thyroid carcinoma:

extensive lymph node compartmental dissections and selective use of radioiodine.

Journal of

Clinical Endocrinology & Metabolism

2009 Apr; 94(4):1086-1088.