The surgical treatment of papillary carcinoma is best divided into two groups based on the clinical characteristics and virulence of these lesions.

The term minimal papillary carcinoma refers to a small papillary cancer, less than 1 cm in diameter, that demonstrates no local invasiveness through the thyroid capsule, that is not associated with lymph node metastases, and that is often found in a young person as an occult lesion when thyroidectomy has been performed for another benign condition. In such instances, especially when the cancer is unicentric and 5 mm or smaller, lobectomy is sufficient and reoperations are unnecessary. Thyroid hormone is given to suppress serum TSH levels, and the patient is monitored at regular intervals.

Most papillary carcinomas are neither minimal nor occult. These tumors are known to be microscopically multicentric in up to 80% of patients; they are also known occasionally to invade locally into the trachea or esophagus, to metastasize commonly to lymph nodes and later to the lungs and other tissues, and to recur clinically in the other thyroid lobe in 7% to 18% of patients if treated only by thyroid lobectomy (26).

The authors firmly believe that the best treatment of papillary cancer is near-total or total thyroidectomy (Fig. 12), with appropriate central and lateral neck dissection when nodes are involved (26a). The so-called cherry-picking operations, which remove only the enlarged lymph nodes, should not be performed. Rather, when tumor is found in the lateral triangle, a modified radical neck dissection should be performed (27) (Fig. 13). At the conclusion of a modified radical neck dissection, the lymph node-bearing tissue from the central and lateral triangles is removed, whereas the carotid artery, jugular vein, phrenic nerve, sympathetic ganglia, brachial plexus, and spinal accessory nerve are spared and left in place. Many times sensory nerves can be retained as well. Prophylactic neck dissection of the lateral triangle should not be performed for papillary cancer; such dissections should be done only when enlarged nodes with tumor are found.

plexus, and spinal accessory nerve are preserved. In a modified neck dissection the sternocleidomastoid muscle is not usually divided, and the jugular vein is not removed unless lymph nodes with tumor are adherent to it. (From Sedgwick CE, Cady B: In Surgery of the Thyroid and Parathyroid Glands. Philadelphia, WB Saunders, 1980, p 180.)

Surgeons with limited experience should probably not perform total or near-total thyroidectomy unless capable of doing so with a low incidence of recurrent laryngeal nerve injuries and permanent hypoparathyroidism, because these complications are serious. Otherwise, it may be advisable to refer such patients to a major medical center where such expertise is available.

After surgery, radioiodine scanning and treatment are commonly used (28, 28a). 131I is taken up by most metastatic papillary cancers, but only if the TSH level is very high and normal thyroid tissue has been removed or ablated. If all or most of a lobe of normal thyroid remains, radioiodine scanning and treatment of metastases cannot be performed effectively. Usually, reoperative completion thyroidectomy is done, and then the radioiodine is given.

Because no randomized prospective study has ever been performed, controversy still exists over the proper treatment of papillary cancer in some patients. Many clinicians now accept that patients with this disease can be separated into different risk groups according to a set of prognostic factors. Using the AGES (29), AMES (30), or MACIS (31) criteria, which evaluate risk by age, distant metastases, extent of local involvement, and size (MACIS adds completeness of excision), almost 80% of patients fall into a low-risk group. Treatment of this low-risk group is most controversial, perhaps because the cure rate is so good, certainly in the high 90% range. Should a lobectomy be done, or is bilateral thyroid resection more beneficial?

Hay and associates studied 1685 low-risk patients treated at the Mayo Clinic between 1940 and 1991; the mean follow-up period was 18 years (32). Of the total, 98% had complete tumor resection and 38% had initial nodal involvement. Twelve percent had unilateral lobectomy, whereas 88% had bilateral lobar resection; total thyroidectomy was done in 18%; while near-total thyroidectomy was performed in 60%. Cause-specific mortality at 30 years was 2%, and distant metastases occurred in 3%. These indices did not differ between the surgical groups; however, local recurrence and nodal metastases in the lobectomy group (14% and 19%, respectively) were significantly higher than the 2% and 6% rates seen after near-total or total thyroidectomy.

This study is excellent. Although no differences in mortality were reported, a threefold increase in tumor recurrence rates in the thyroid bed and lymph nodes was reported in the lobectomy group. In addition, this study recognizes patients’ anxiety about tumor recurrence, and their strong desire to face an operation only once and to be cured of their disease. If the operation can be performed safely with low morbidity, this study supports the use of near-total or total thyroidectomy for patients with low-risk papillary cancer.

For high-risk patients, it is agreed that bilateral thyroid resection improves survival (29) and reduces recurrence rates (33) when compared with unilateral resection. Such patients also receive ablation or treatment with radioiodine as indicated (34).

In general, our studies (34,35) and those of Mazzaferri and Jhiang (36) have demonstrated a decrease in mortality and in tumor recurrence after near-total or total thyroidectomy followed by radioiodine ablation or therapy.