Persistent and recurrent disease in patients with papillary thyroid carcinoma with clinically apparent (cN1), but not extensive, lymph node involvement and without other factors for poor prognosis.
OBJECTIVE
Lymph node metastases (LNM) are frequent in patients with papillary thyroid cancer (PTC). The risk of persistent disease (PD) and tumor recurrence (TR) is increased when factors for poor prognosis other than LNM exist, when LNM are numerous, large, detected by preoperative ultrasonography (US), or exhibit extranodal extension. This study evaluated the risk of PD and TR in patients with LNM not exhibiting these characteristics.


METHODS
Eighty-six patients with 5 or fewer LNM detected during intraoperative inspection, but not by preoperative US, who had no other factors for poor prognosis [tumors > 4 cm, extensive extrathyroid invasion, vascular invasion, aggressive histological subtype, distant metastases, incomplete tumor resection], were studied. All patients underwent total thyroidectomy followed by radioiodine ablation. PD was defined as metastases on initial post-therapy whole-body scans (RxWBS) or detected by imaging methods up to 12 months after ablation. TR was defined as structural disease diagnosed more than one year after ablation in patients without PD.


RESULTS
PD was diagnosed in 3/86 patients (3.5%). TR was observed in 2/83 patients (2.5%) after 62 months of follow-up. There was no case of death due to the disease. A correlation was observed between pre-ablation Tg and PD or TR [1/48 (2%) with Tg ≤ 2 ng/mL versus 2/22 (9%) with Tg > 2 ≤ 10 ng/mL versus 2/7 (28.5%) with Tg ≥ 10 ng/ml)]. It is noteworthy that 38 patients had up to 3 positive LN and pre-ablation Tg ≤ 2 ng/ml, and none of them had PD or TR.


CONCLUSIONS
The frequency of PD and TR was low in patients with PTC with 5 or fewer LNM and without other factors for poor prognosis. Low postoperative stimulated Tg was predictive of the absence of PD and TR in these patients.
Santa Casa de Belo Horizonte, Belo Horizonte, MG, BR.
Mariana de Souza
Mde S
Furtado
Santa Casa de Belo Horizonte, Belo Horizonte, MG, BR.
Pedro Weslley
PW
Rosario
Santa Casa de Belo Horizonte, Belo Horizonte, MG, BR.
Maria Regina
MR
Calsolari
D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000473:pathology / Q000628:therapy*; D002291:Carcinoma, Papillary; D002648:Child; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012307:Risk Factors; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000473:pathology / Q000628:therapy*; D013965:Thyroidectomy; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D007457:Iodine Radioisotopes