Role of RAI in the management of incidental N1a disease in papillary thyroid cancer

Abstract

Background Following total thyroidectomy (TT) for papillary thyroid cancer (PTC), pathological assessment can occasionally reveal incidental perithyroidal lymph nodes (LNs) with occult metastases. These cN0pN1a patients often receive radioactive iodine (RAI) therapy for this indication alone. The aim of this study was to determine the central compartment nodal recurrence-free survival in patients treated without RAI compared to those who received RAI treatment. Methods An institutional database of 3664 previously untreated patients with differentiated thyroid cancer operated between 1986 and 2010 was reviewed. 232 pT1-3 patients managed with TT and no neck dissection were subsequently found to have incidental level 6 LNs on pathology. Patients with other indications for RAI, such as extrathyroidal extension and close or positive margins, were excluded. One hundred and four patients remained for analysis. Kaplan-Meier method was used to determine central neck LN recurrence free survival (RFS). Results The median age of the cohort was 40 years (range 17–83). The median follow up was 53 months (range 1–211). The median number of positive LNs removed and maximum LN diameter was 1 (range 1–8) and 5mm (range 1–16mm), respectively. 67 (64%) patients had adjuvant RAI and 37 (36%) did not. Patients with vascular invasion (p=0.01), LNs >2mm (p=0.07) and >2 positive nodes (p=0.06) were more likely to be selected for adjuvant RAI therapy. Patients without RAI therapy had similar 5 year central neck LN RFS to those treated with RAI; 96.2% vs. 94.6% respectively (p=0.92). Conclusion There is no difference in the 5 year central compartment nodal recurrence-free survival in patients treated without RAI compared to those who received RAI treatment.

Incidental positive lymph nodes in patients with papillary thyroid cancer is independently associated with recurrent disease

“…This study describes a clinical scenario faced by surgeons who do not routinely perform prophylactic central neck dissections, and should be seen as raising the very practical question of whether positive incidental LNs should be considered differently from positive LNs obtained as part of a planned central neck dissection. Our results contrast with the findings of the only other study on the subject of incidental positive LNs, in which there was a recurrence rate of 5.8% after 5 years . This is lower than in our study, where 17% (7/42) of patients with iLNM had recurrent disease.…”

A Diagnostic Dilemma: Skip Metastasis in Papillary Thyroid Cancer

“…Although our study reveals that skip metastasis can be seen in mPTC, Chae et al 20 reported that 26 per cent of patients with mPTC received potentially unnecessary RAI. In addition, Wang et al 21 reported that in the selected PTC patients with incidental central compartment nodal disease, there is no difference in the five-year central compartment nodal recurrence-free survival in patients treated without RAI compared with those who received RAI treatment. Indeed, a careful follow-up for lateral LNs after surgery may solve these controversies in clinical practice, but further prospective studies are needed in this topic.…”

Clinical outcomes of low and intermediate risk differentiated thyroid cancer patients treated with 30mCi for ablation or without radioactive iodine therapy

“…Furthermore, Wang and cols. demonstrated that properly selected patients, even with affected lymph nodes, should not necessarily receive RRA (30,31).…”