Background: Arguably patients undergoing total thyroidectomy for papillary thyroid cancers (PTC) are more likely to have negative radioactive iodine uptake and low/undetectable thyroglobulin levels if the central compartment lymph node dissection (CCLND) is performed routinely irrespective of the macroscopic appearance of the LN. The aim of this study was to determine whether routine CCLND leads to more favourable outcome in the first year after treatment for well-differentiated thyroid cancer.
Methods: Clinical, operative and radiological data on patients operated in a University centre were collected in a prospective database. Parameters in a recent group of patients who underwent routine CCLND were compared with similar values in a historical cohort of patients.
Results: CCLND was performed in 54 patients (Table). A further 41 patients who presented with palpable local LN metastases and underwent radical neck dissection ±CCLND were excluded from this analysis. All 54 patients analysed had no macroscopic evidence of LN involvement. The yield of LN ranged 139 (median 8). Metastatic PTC was identified in local LN in 34/44 patients with percentage of involved LN ranging 26100% (median 57%). This allowed for accurate lymph node staging in all patients (N0 n=10, N1 n=34). There was no correlation between tumour stage/size and likelihood of positive LN.
There was a trend for lower radioactive iodine (RAI) uptake after first ablative dose of I131 in patients who underwent CCLND (Table). There was a notable difference in the levels of thyroglobulin at 3 months (P=0.09) and 1 year (P=0.18) in favour of those who underwent CCLND (Table).
|CCLND (20072009, n=54)||Historical group (20002007, n=193)|
|Age||47 years (1593 years)||46 years (1880) years|
|Tumour size||36 mm (295 mm)||30 mm (0.590 mm)|
|Tumour type||46 PTC:4 FTC:4 HurthTC||122PTC:46 FTC:25 Hurth|
|Lymph nodes retrieved||Median 8 (range 139)|||
|Lymph nodes positive for disease||Median 4 (range 014)|||
|After first ablative dose of I131||1.39% (05.8%)||2.7% (035%)|
|At 3 months after I131||0.02% (00.16%)||0.03% (07%)|
|3 Months postop||6.9 (526.6)||86.63 (51000)|
|12 Months postop||8.7 (529.1)||75.62 (51000)|
Conclusion: Routine CCLND leads to a trend towards lower RAI uptake and lower thyroglobulin levels in the first year after treatment for differentiated thyroid cancer. Whether such patients will have lower rates of local recurrence remains to be determined during long-term follow-up.