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


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.


CONCLUSIONS
Precise LN staging by prophylactic neck dissection for tumors initially staged T1N0 modified the indication for radioiodine ablation for 30% of patients.
Bonnet
Stéphane
S
Department of Oncologic Surgery, Institut Gustave Roussy, Villejuif Cedex, France.
Hartl
Dana
D
Leboulleux
Sophie
S
Baudin
Eric
E
Lumbroso
Jean D
JD
Al Ghuzlan
Abir
A
Chami
Linda
L
Schlumberger
Martin
M
Travagli
Jean Paul
JP
D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D003131:Combined Modality Therapy; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011379:Prognosis; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D013965:Thyroidectomy; D016896:Treatment Outcome; D014463:Ultrasonography
D007457:Iodine Radioisotopes