A. L. Madenci1, R. W. Frank2, B. C. Stack2, J. J. Shin1 1Brigham And Women’s Hospital,Boston, MA, USA 2University Of Arkansas,Little Rock, AR, USA
Introduction: The appropriate extent of thyroidectomy and lymph node dissection (LND) for children with well-differentiated thyroid carcinoma (WDTC) remains unclear. Management strategies may differ from those for adults. We conducted a systematic review to evaluate if children with WDTC have different survival, recurrence, or complication rates based on extent of thyroid resection and neck dissection.
Methods: We performed a computerized search of MEDLINE and Embase from 1966 to August 2017, supplemented with manual searches. Inclusion criteria were studies of patients diagnosed with WDTC at age <21 years, which evaluated thyroid resection and/or LND. Independent reviewers extracted data, with outcomes of survival, recurrence, postoperative complications, study designs, and potential confounders.
Results: Forty-nine criterion-meeting studies included 3821 pediatric patients who underwent resection of WDTC, including total thyroidectomy (TT; n=2512), subtotal thyroidectomy (STT; n=460), and lobectomy (n=725), with some patients undergoing multiple procedures. There were no prospective studies. Among studies comparing TT to STT, none detected a significant difference in overall survival (OS) (0/19 studies, 0%) and one detected a higher DFS after TT (1/12, 8%). Recurrence results were mixed (2/13, 15% detected decreased recurrence after TT; 1/13, 8% detected decreased recurrence after STT), and complications were similar among all studies. Among studies comparing TT to lobectomy, none (0/13, 0%) detected a significant difference in OS, one detected significantly increased DFS after TT (1/7, 14%), two detected significantly decreased recurrence after TT (2/8, 25%), and none (0/2, 0%) detected a significant difference in complications. Comparing STT and lobectomy, none reported a difference in OS (0/6, 0%), DFS (0/4, 0%), recurrence (0/3, 0%), or complications (0/1, 0%). Additionally, 17 studies reported outcomes following LND. Of the two small stage-specific studies limited to N+ patients, neither (0/2, 0%) detected a significant difference in OS or recurrence with LND, compared to no LND. Among 15 studies evaluating LND that were not stage-specific, none reported a difference in OS (0/4, 0%). One (1/5, 20%) study reported a significantly decreased DFS among N+ patients who underwent LND, compared to N0 who did not undergo LND (P<0.001). Recurrence results were mixed: 2/12 (17%) studies reported increased recurrence after LND, 6/12 (50%) reported no difference, and 3/12 (25%) reported decreased recurrence after LND. Two (3/7, 43%) studies documented significantly higher complication rates after LND.
Conclusion: In this systematic review of thyroidectomy and LND for pediatric WDTC, studies were generally underpowered and not stage specific. These retrospective results were mixed with respect to OS, DFS, recurrence, and post-operative complications.