Dr. Sheldon Rubenfeld Board Certified in Internal Medicine and in Endocrinology, Diabetes, and Metabolism

Papillary and Follicular Cancer

The outlook for patients with papillary or follicular thyroid cancer is very good. With the appropriate treatment, more than 90% of all patients will be cured. While cure rates have been determined for groups of patients with papillary or follicular thyroid cancer, it is nearly impossible to predict the outcome for an individual patient. Each person is unique and a patient’s prognosis is determined by multiple factors. The most important patient factor is age, although gender is also important. The most important characteristics of the cancer are size, type, extent of local invasion and distant metastasis, although the number of tumors in the thyroid gland may influence the patient’s prognosis. A patient’s prognosis is also determined by the extent of surgery and the follow-up treatment

Broadly speaking, the objectives of follow-up after the initial treatment of most patients with differentiated thyroid cancers are to confirm the absence of any residual thyroid tissue; to confirm the presence or absence of any recurrent thyroid cancer; and to treat recurrences, if necessary. These objectives are not applicable to a patient who has been treated with only a lobectomy.

The absence of all thyroid tissue increases a physician’s ability to track the status of a thyroid cancer patient after the initial treatment. If there is any residual thyroid tissue in the thyroid bed after a subtotal thyroidectomy and radioactive iodine treatment, it may not be possible to distinguish between residual normal thyroid tissue and residual or recurrent thyroid cancer. On the other hand, if all normal thyroid tissue and all cancerous thyroid tissue have been eliminated from the thyroid bed, then anything that lights up on future scans is likely to be a recurrence. Even though most recurrences of papillary and follicular cancers appear within the first five years after initial treatment, thyroid cancer sometimes recurs decades later. Therefore, a patient must return regularly, over a long period of time, to the physician for follow-up visits.

The physician identifies residual or recurrent cancer by the medical history, physical examination, blood tests such as thyroglobulin, whole body scans, and other diagnostic procedures, such as ultrasounds, MRIs, CAT scans, and PET scans. After the initial postoperative evaluation, a patient who has had only a lobectomy will see the physician at yearly intervals. During these visits, the patient may have only a medical history, physical examination, blood work and, possibly, a thyroid ultrasound. On the other hand, the follow-up of a patient who has had a subtotal thyroidectomy and radioactive iodine treatment is more complicated. The relationship between thyroglobulin and differentiated thyroid cancer is an important one. Only thyroid cells produce thyroglobulin; therefore, an elevated thyroglobulin after a thyroidectomy and successful radioactive iodine ablation of all residual thyroid tissue may indicate recurrence of thyroid cancer.

Occasionally, differentiated thyroid cancer, especially poorly differentiated thyroid cancer, progresses in spite of surgery, radioactive iodine treatment, and external-beam radiation. When progression occurs, a few patients may temporarily benefit from chemotherapy. Oncologists, or cancer specialists, usually supervise chemotherapy treatments.