166P - Extent of neck dissection in locally advanced thyroid cancers
|Date||17 December 2016|
|Event||ESMO Asia 2016 Congress|
|Topics|| Thyroid Cancer
Surgery and/or Radiotherapy of Cancer
|Citation||Annals of Oncology (2016) 27 (suppl_9): ix52-ix52. 10.1093/annonc/mdw580|
R. Vaish1, A. Mahajan2, S. Shah1, S. Sharma1, D. Chaukar1, S. Thiagarajan1, A. D'Cruz1
Thyroid cancer has an indolent course with low mortality. The extent of neck dissection is a contentious issue. Clearance of level IIB and V is associated with larger incision with clearance around spinal accessory nerve resulting in cosmetic and functional morbidity.
544 thyroidectomies were performed for locally advanced thyroid cancer. Level wise node sampling with histopathology details were available for 92 patients with 160 lateral neck dissections which were analysed further. The incidence of level IIB and V metastasis and factors predicting were analysed. Demographic and Histopathologic details were entered in SPSS version 20 and descriptive analysis was used to calculate the frequency. Univariate analysis was performed using chi square test and multivariate analysis was performed using binary logistic regression.
Ninety-two patients underwent thyroidectomy with neck dissection 55 papillary, 23 variant of papillary, 7 medullary and 7 for poorly/anaplastic thyroid carcinoma. Seventy three T3 and 19 were T4 thyroid carcinoma. Level IIB was cleared in 142 and level V in 74 neck dissections. Level V was cleared only when level II through IV sampling showed metastatic node on frozen section. Level IIb was positive in 7% (10/142) and level V in 18.9% (14/74) of cases. Two of 10 level IIB were the isolated level of metastases. On univariate analysis the factors predicting level IIB metastasis were T stage, level IIA, III and IV metastasis while for level V metastasis were presence of lymphovascular emboli (LVE), level IV and VI metastasis. On multivariate analysis independent predictor for level IIB metastasis were T stage, level IV metastasis and LVE while for level V metastasis were level IV metastasis.
Incidence of IIB metastasis is low and should be addressed in T4 thyroid cancer with level IV metastasis. However, high incidence of level V metastasis warrants level V clearance in lateral compartment positive neck.
Clinical trial indentification
Legal entity responsible for the study
Tata Memorial Hospital
All authors have declared no conflicts of interest.