Robert 1. Sataloff

CARE OF THE PROFESSIONAL VOICE Robert I. Sataloff, MD, DMA, Associate Editor

I,)Ut fldl 01 Singing, SOOCIObLI 1)ecLInbet 2(11

Volunic 64, No. 2, pp. 195-198 Copyright 16 2007 National Association of Teachers of Singing

INTRODUCTION

T

hyroid cancer is relatively common. It accounts for 1% to

1.5% of all new cases of cancer in the United States,' amount-

ing to between 13,000 and 20,000 new cases of thyroid can-

cer annually. About 1,100 to 1,300 deaths result from thy-

roid cancer each year in the United States. 2 Normal thyroid hormone

levels are important to laryngeal function, so thyroid damage even

from medical cancer treatment can cause voice problems in singers.

In addition, the thyroid gland lies in close proximity to the larynx and

the nerves that move the vocal folds. Vocal fold paresis (weakness) or

paralysis are fairly common complications of thyroid surgery. It is help-

ful for singing teachers to have a basic familiarity with the nature, eval-uation, and treatment of thyroid cancer.

ANATOMY

The thyroid gland is located below the strap muscles of the neck, in front

of the second and third tracheal rings, and just below the cricoid car-

tilage of the larynx. The right and left lobes of the thyroid gland are con-

nected by a narrow band called the isthmus. Berry ligaments suspend

the thyroid gland to the larynx and trachea. The recurrent laryngeal

nerves, which innervate all of the laryngeal muscles except the cricothy-

roid muscles, course through the tracheo-esophageal groove deep to

the thyroid gland. They run close to the inferior thyroid arteries and

Berry ligaments which must be operated upon during thyroidectomy.

The superior laryngeal nerves also run in close approximation to the

upper portions of the thyroid gland and the superior thyroid arteries.

CLINICAL PRESENTATION

Typically, thyroid cancers present as masses or "nodules" in the thy-

roid gland. However, most nodules are not cancer. Palpable thyroid

nodules (bumps that can be felt in the neck) are present in 4% to 7%

of adults in the United States.' When cadavers are dissected, nodules

that were not palpable are found in between 37% and 57% of thyroid

glands.' Only about 5% of thyroid nodules are cancerous in adults.'

However, in patients under twenty years of age, 20% to 50% of thy-roid nodules are malignant. 6 In adults, nodules in males are cancer-

Thyroid Cancer Robert Thayer Sataloff

Novi-mm-OM : ( 2007 195

Robert T Sata1off, MD, DMA

ous approximately twice as frequently as they are in fe-males.

When thyroid neoplasms cause hoarseness, localized

neck pain, difficulty breathing or swallowing, or other

such symptoms that are uncommon for benign nodules,

malignancy is suspected readily. However, many thy-

roid cancers present simply as painless, enlarging masses.

Hence, any thyroid mass should be evaluated thoroughly.

Certain aspects of the patient's history are of particular

importance. The presence of conditions such as

Hashimoto's thyroiditis (an autoimmune condition),

Grave's disease, goiter, or a family history of medullary

carcinoma of the thyroid, all increase the risk of thyroid

cancer. A history of normal thyroid function is routine

in thyroid cancer patients, although hypothyroidism

may be present.

Physical examination of the neck in thyroid cancer

patients usually reveals a single or dominant nodule that

is at least 1 cm in diameter. This finding warrants a com-

prehensive evaluation, in most cases. Smaller nodules in

asymptomatic patients often are followed clinically and

by ultrasound. However, when a nodule is palpated, it

should be studied to determine whether it is isolated,

dominant, or simply one of many lesions within a multi-

nodular, goiterous thyroid gland. Nevertheless, it must be remembered that the presence of a multinodular goi-

ter does not rule out the possibility of cancer. In fact, as

many 7.5% of patients with a multinodular goiter may

also have thyroid cancer. 7 If palpable lymph nodes are

present in the neck in association with a solitary or dom-

inant thyroid mass, thyroid cancer should be suspected

(although it is not the only condition that can cause this

clinical picture). A nodule that is hard, immobile, fixed to surrounding structures, and poorly defined is also

more likely to be cancerous than a smooth, well circum -

scribed mobile nodule. Nodules larger than 2 cm are par-ticularly likely to harbor cancer.' In addition to examina-

tion of the thyroid and lymph nodes of the neck, the

larynx should be visualized in every case suspected of

having a thyroid abnormality, particularly a thyroid mass.

The evaluation of a patient with thyroid disease in-

volves not only physical examination, but also blood tests and imaging studies. Most physicians perform com-

mon thyroid function tests such as T3, T4, and TSH lev-

els. When malignancy is suspected, thyrotropin assay is

particularly helpful. Thyroglobulin levels often are ordered,

but they are not especially helpful when evaluating a

thyroid nodule; however, they are very useful as tumor

markers when recurrent thyroid cancer is suspected af-

ter total thyroidectomy and radiation. Many other thy-

roid blood tests may he ordered in selected cases includ-

ing antithyroid antibodies, serum calcitonin levels, RET

proto-oncogene screening, and other tests, the details

of which are beyond the scope of this article.

Thyroid imaging is performed routinely when masses

are identified. Thyroid ultrasound remains among the

most common studies. It is painless and involves no ra-

diation. Ultrasonography can detect lesions and deter-

mine whether nodules are cystic, solid, or mixed. Ultra-

sound is particularly valuable for its ability to measure

nodules accurately and allow nodule growth (or stabil-

ity) to be tracked over time. Although solid nodules on

ultrasound are more likely to be malignant than cystic

nodules, ultrasound cannot differentiate between ma-

lignant and benign solid nodules.' Ultrasound is very

helpful, however, in guiding fine needle aspirate biopsy

(FNAB), a minimally invasive office procedure for biop-

sying thyroid masses. In selected cases, CT and/or MRI

of the neck may be of value, particularly in assessing the

possibility of lymph node disease.

Thyroid uptake scans (thyroid scintigraphy) have been

used routinely in the evaluation of suspected thyroid can-

cer for more than a half century. Cancerous thyroid nod-

ules do not concentrate radio-labeled iodine tracer as well

as benign nodules. So benign nodules tend to be "hot,"

and malignant nodules tend to be 'old" on uptake scans. Unfortunately, accuracy of differentiation is not particu-

larly good. For example, only 10% to 15% of cold nod-

ules are actually cancerous; and cancer occurs in hot nod-ules with a frequency of about 4%. "'Nevertheless, thyroid

scanning is still useful particularly in selected patients, including particularly those with hypothyroidism, and

those with thyrotropin abnormalities.

FNAB is now the main stay of thyroid nodule diag-

nosis. The technique is fast, generally safe, inexpensive

and reasonably accurate, with a false-negative rate of

2.4% and false-positive rate of 1.2%, yielding an overall accuracy of over 95%h1 FNAB is not always definitive,

however. In addition to yielding reports of "benign" or

"malignant" disease, FNAB may also produce "nondi-

agnostic" specimens, and specimens reported as "sus-picious or indeterniinant." When definitive diagnosis

196 JOURNAL O SINGING

Care of the Professional Voice

cannot be established, thyroid surgery is required in

many cases, particularly if a diagnosis still has not been

reached on repeat FNAB with ultrasound guidance.

Nevertheless, FNAB has decreased the incidence of

avoidable thyroid surgery. When surgery is performed

for suspected thyroid cancer, cancer is found approxi-

mately 40% of the time, up from approximately 15% in

the days prior to FNAB.'2

THYROID PATHOLOGY AND ITS MANAGEMENT

Fortunately, most thyroid cancer falls into the "well differ-

entiated thyroid carcinoma" category. These include pap-

illary (79%) and follicular (13%) carcinoma.' 3 These tu-

mors arise from follicular cells of the thyroid gland and have

excellent survival rates. Papillary cancer ten year survival

rates are 90% to 95%, and those for follicular carcinoma

are 80% to 85%.' About 3% to 5% of all thyroid cancers

arise from the parafollicular C-cell and are medullary thy-roid carcinomas. The ten year survival rate for this tumor

is 65% to 80%) About 5% to 7% of thyroid cancers are pri-

mary lymphoma of the thyroid, and they have a five year

survival rate of about 50%.' Fortunately, only 2% to 5%

of thyroid cancers are anaplastic or undifferentiated thy-roid carcinoma. This lesion is associated with very poor

survival, usually measured in months.

Treatment for thyroid cancer depends upon the spe-cific pathology and will not be reviewed in detail here.

It may include thyroid surgery (partial or total removal

of the thyroid gland), radiation (radioactive iodine or external radiation), dissection and removal of lymph

nodes in the neck, or other modalities. In many cases,

thyroid function is ablated entirely, and thyroid replace-

ment therapy must be used for the rest of the patient's

life. Restoration of adequate systemic thyroid function

is usually possible, and this aspect of thyroid cancer usu-

ally will not end a singing career. It is also usually pos-

sible to remove the thyroid gland without injuring the la-

ryngeal nerves; laryngeal injury is a well recognized risk

of thyroid surgery and can occur even in the hands of

the best surgeon. Surgical experience, often combined with

the use of intraoperative nerve monitoring, provides the

best chance of avoiding injury to the nerves that move the vocal folds. Newer techniques such as minimally in-vasive thyroid surgery provide better cosmetic results

and also may be considered if a surgeon is highly expe-

rienced in this approach. However, for singers, preser-

vation of the laryngeal nerves is the main concern, sec-

ondary only to curing the cancer. Thyroid cancer is

certainly a serious matter, but it will not necessarily end

a vocal career.

NOTES

A. Wingo, T. Tong, and S. Boldien, "Cancer Statistics," CA: A

Cancer Journal for Clinicians 45, no. 1 (January/February

1995): 8-30.

2. L. J. DeGroot, E. L. Kaplan, M. McCormick, and F. M. Straus,

"Natural History Treatment, and Course of Papillary Thyroid

Carcinoma,' Journal of Clinical Endocrinology and Metabolism

71, no. 2 (August 1990): 414-424.

3. E. L. Mazzaferri, "Thyroid Cancer in Thyroid Nodules: Find-

ing a Needle in a Haystack:' American Journal of Medicine

93(1992): 359-369.

4. C. 0. Rice, "incidence of Nodules in the Thyroid,' Archives

ofSurgery 24 (1932): 505-515; J. D. Mortensen, L. B. Woiner,

and W. A. Bennett, 'Gross and Microscopic Findings in

Clinically Normal Thyroid Glands," Journal of Clinical

Endocrinology and Metabolism 15 (1955): 1270-1282.

5. R. 1.eeper, "Thyroid Carcinoma,' Medical Clinics of North

America 69, no. 5(1985): 1079-96.

6. H. Goepfert, W. J. Dichtel, and N. A. Samaan, "Thyroid

Cancer in Children and Teenagers:' Archives of Otolaryngology

110 (1985): 72-75; C. McHenry, M. Smith, A. Lawrence, et

al., "Nodular Thyroid Disease in Children and Adolescents,

Annals of Surgery 54 (1988):444-447; H. Hathaway, "Diagnosis

and Management of Thyroid Nodule:' Otolaryngology Clinics

of North America 23, no. 2 (April 1990): 303-337.

7. K. B. Koh and K. W. Chang, "Carcinoma in Multinodular

Goiter:' British Journal of Surgery 79 (1992): 266-267.

8. J. M. Miller, S. R. Kini, and J. I. Hamburger, "Diagnosis of

Malignant Follicular Neoplasm of the Thyroid by Needle

Biopsy:' Cancer 55 (1985): 2812-2817.

9. M. Ashcraft and A. VanHerle, "Management of Thyroid

Nodules 1' Head and Neck Surgery (January/February 1981):

216-227; M. Ashcraft and A. VanHerle, "Management of

Thyroid Nodules II," Head and Neck Surgery (March/April

1981): 297-322.

10. Ibid.

11. J. P. Campbell and H. C. Pillsbury, "Management of the Thy-

roid Nodule:' Head and Neck 11(1989): 414-425.

12. D. Caruso and E. L. Mazzaferri, "Fine Needle Aspiration

Biopsy in the Management of Thyroid Nodules:' Endo-

crinologist 1(1991): 194-197.

NOVEMBER/DECEMBER 2007 197

Robert T Sataloff, MD, DMA

13. S. A. Hundahl, 1. D. Fleming, A. M. Fregman, and H. R.

Menck, "A National Cancer Data Base Report on 53,856

Cases of Thyroid Carcinoma Treated in the U.S. 1985-1995:'

Cancer Journal 83 (1998): 2638-2648.

14, E. L. Mazzaferri and R. L. Young, "Papillary Thyroid

Carcinoma: A Ten-Year Follow-up Report on the Impact of

Treatment in 576 Patients,' American Journal of Medicine 70

(1981): 511-518; G. Emmerick, Q. 1)hu, A. Siperstein, et al.,

"Diagnosis, Treatment, and Outcome of Follicular Carcinoma:"

Cancer 72 (1993): 3287-3295; A. Shaha, T. R. Loree, and J. P.

Shah, "Prognostic Factors and Risk Group Analysis in

Follicular Carcinoma of the Thyroid," Surgery 118 (1995):

1131-1136.

15. Q. Y. Dub, J. J. Sancho, S. Greenspan, T. K. Hunt, M. Galante,

A. A. deLorimer, F. A. Conte, and 0. H. Clark, "Medullary

Thyroid Carcinoma: The Need for Early Diagnosis and Total

Thyroidectomy," Archives of Surgery 124, no. 10 (October

1989): 1206-1210.

16. D. L. Rasbach, M. S. Mondschein, N. L. Harris, et al., "Malig-

nant Lymphoma of the Thyroid Gland: A Clinical and

Pathologic Study of 20 Cases:' Surgery 6 (1985): 1166-1170;

J. I. Hamburger, J. M. Miller, and S. R. Kini, "Lymphoma of

the Thyroid:' Annals of Internal Medicine 99(1983): 685-689.

Robert 1. Sataloff, MD, DMA is Professor and Chairman of the Depart-

ment of Otolaryngology—Head and Neck Surgery and Associate Dean for Clinical Academic Specialties at Drexel University College of Med-icine. He is also on the faculty at Thomas Jefferson University, the University of Pennsylvania, Temple University, and the Academy of

Vocal Arts. Dr. Sataloff is Conductor of the Thomas Jefferson Univer-

sity Choir and Orchestra and Director of The Voice Foundation's Annual Symposium on Care of the Professional Voice. Dr. Sataloff is also a pro-

fessional singer and singing teacher. He holds an undergraduate

degree from Haverford College in Music Composition, graduated from

Jefferson Medical College, received a DMA in Voice Performance from

Combs College of Music, and completed his Residency in Otolaryn-

gology-Head and Neck Surgery at the University of Michigan. He also completed a Fellowship in Otology, Neurotology, and Skull Base Surgery at the University of Michigan. Dr. Sataloff is Chairman of the Board of Directors of The Voice Foundation and of the American Institute for

Voice and Ear Research. He is Editor-in-Chief of the Journal of Voice, Editor-in-Chief of the Ear, Nose and Throat Journal, an Associate Edi-tor of the Journal of Singing, and on the Editorial Board of Medical

Problems of Performing Artists and numerous major otolaryngology journals in the United States. Dr. Sataloff has written over 600 pub-lications, including thirty-six books. Dr. Sataloff's medical practice is limited to care of the professional voice and to otology/neurotology/skull

base surgery.