Treatment of sporadic nonmedullary thyroid carcinomas in pediatric age

The treatment of differentiated thyroid cancer in children: emphasis on surgical approach and radioactive iodine therapy

Pediatric thyroid cancer is a rare disease with an excellent prognosis. Compared with adults, epithelial-derived differentiated thyroid cancer (DTC), which includes papillary and follicular thyroid cancer, presents at more advanced stages in children and is associated with higher rates of recurrence. Because of its uncommon occurrence, randomized trials have not been applied to test best-care options in children. Even in adults that have a 10-fold or higher incidence of thyroid cancer than children, few prospective trials have been executed to compare treatment approaches. We recognize that treatment recommendations have changed over the past few decades and will continue to do so. Respecting the aggressiveness of pediatric thyroid cancer, high recurrence rates, and the problems associated with decades of long-term follow-up, a premium should be placed on treatments that minimize risk of recurrence and the adverse effects of treatments and facilitate follow-up. We recommend that total thyroidectomy and central compartment lymph node dissection is the surgical procedure of choice for children with DTC if it can be performed by a high-volume thyroid surgeon. We recommend radioactive iodine therapy for remnant ablation or residual disease for most children with DTC. We recommend long-term follow-up because disease can recur decades after initial diagnosis and therapy. Considering the complexity of DTC management and the potential complications associated with therapy, it is essential that pediatric DTC be managed by physicians with expertise in this area.

Long-term outcome in 215 children and adolescents with papillary thyroid cancer treated during 1940 through 2008

BACKGROUND

Controversy exists regarding the aggressiveness of initial therapy in childhood papillary thyroid cancer (PTC). Few studies with long-term outcome exist and second primary malignancies have rarely been analyzed.

METHODS

We studied 215 PTC patients younger than 21 years old managed during 1940 through 2008. The patients were aged 3-20 year old (median age = 16 years); the median follow-up was 29 years. Recurrence and mortality details were taken from a computerized database.

RESULTS

Median primary tumor size was 2.2 cm. Six percent had distant metastases at presentation, 5% had incomplete tumor resection, 86% had nodes removed at initial surgery, and 78% had nodal metastases. After complete surgical resection, PTC recurred in 32% by 40 years. At 20 years, the recurrence rates at local, regional, and distant sites were 7, 21, and 5%, respectively. During 1940-1969, local and regional recurrence rates after unilateral lobectomy (UL) were significantly (P < 0.001) higher than after bilateral lobar resection (BLR). During 1950-2008 radioiodine remnant ablation (RRA) was administered within 18 months to 32%; it did not diminish the 25-year regional recurrence rate of 16% seen after BLR alone (P = 0.86). Only two fatal events from PTC occurred at 28 and 30 years, for a cause-specific mortality at 40 years of only 2%. All-causes mortality rates did not exceed expectation through 20 years, but from 30 through 50 years, the number of deaths was significantly (P < 0.001) higher than predicted. Fifteen of 22 deaths (68%) resulted from nonthyroid malignancy.

CONCLUSION

Survival from childhood PTC should be expected, but later death from nonthyroid malignancy is disconcerting. Seventy-three percent of those who died from nonthyroid malignancy had received postoperative therapeutic irradiation.