Prophylactic lymph node dissection for papillary thyroid cancer less than 2 cm: implications for radioiodine treatment.

　　J Clin Endocrinol Metab   2009  Apr  94(4) :1162-7

　　PMID：19116234浙江省肿瘤医院核医学科叶雪梅

　　OBJECTIVE: Prophylactic neck dissection for small papillary carcinoma remains controversial. Radioiodine ablation is not recommended for tumors less than 10 mm and depends on various factors for tumors between 10 and 20 mm. The aim was to determine the effect of lymph node (LN) staging on the indication for treatment with radioiodine. PATIENTS AND METHODS: We conducted a retrospective study of 115 patients presenting with papillary thyroid carcinoma less than 2 cm without ultrasonographically detectable cervical LN treated by total thyroidectomy and complete selective dissection of the central and lateral compartment. Radioiodine treatment was based on definitive pathology (tumor and LN). Follow-up was based on neck ultrasound and thyroglobulin levels. RESULTS: LN were found for 41.7% of cases. Radioiodine was not used for 42% of patients with tumors less than 20 mm and no metastatic LN. Fifty-eight percent of patients were treated with radioiodine due to LN metastasis, extracapsular thyroid invasion, or unfavorable histological subtype. LN status affected the indication for radioiodine in 30.5% of cases classified as T1, 12 cases with tumors less than 10 mm but with LN metastases (who received radioiodine), and 13 cases with tumors between 10 and 20 mm but without LN metastases (who did not receive radioiodine). Definitive vocal fold paralysis and hypoparathyroidism each occurred in 0.9% of cases. At 1 yr, ultrasound was normal in all patients, and recombinant human TSH-stimulated thyroglobulin was undetectable for 97% of the patients. CONCLUSION: Precise LN staging by prophylactic neck dissection for tumors initially staged T1N0 modified the indication for radioiodine ablation for 30% of patients.

　　目前，对小的甲状腺乳头状癌是否行预防性颈淋巴结清扫术仍存在争议。我们不推荐对小于10 mm的甲状腺癌采用放射性碘治疗，对10-20 mm的甲状腺癌是否采用放射性碘治疗取决于其病理和其他各种因素。本研究的目的是根据淋巴结分级确定放射性碘疗法的适应症。病人和方法：我们对115例患者进行了回顾性研究，所有入选患者甲状腺乳头状癌均小于2cm，超声均未发现颈淋巴结转移的，且采用的术式为甲状腺全切，和甲状腺中央区和外侧区选择性颈淋巴结清扫术。放射性碘治疗的适应症主要由病理分期（肿瘤和淋巴结）来决定。依据颈部超声和甲状腺激素水平对患者进行随访。结果：发生淋巴结转移的患者占41.7%。未发生淋巴结转移，肿瘤小于20 mm，且未采用放射性碘治疗的患者占42%。58%的患者由于淋巴结转移、肿瘤侵出甲状腺组织，及不良的组织学分型而采用放射性碘治疗。放射性碘治疗的适应症取决于淋巴结的情况，T1期的患者为30.5%，12例患者肿瘤小于10 mm伴淋巴结转移（接受了放射性碘治疗），13例患者肿瘤10- 20 mm不伴淋巴结转移（未接受放射性碘治疗），0.9%的病例发生了声带麻痹和甲状旁腺机能减退术后并发症。在随访1年时，所有病人的超声检查正常，97%的患者未检测到重组人促甲状腺激素刺激。结论： T1N0期的甲状腺肿瘤预防性颈淋巴结清扫术可以使淋巴结分级更精确，30%的患者可以根据此分级调整放射性碘治疗的适应症。