Incidence of Thyrioid Malignancy in Completion Thyroidectomy – A Single Institution Experience over Ten Years
Zhihong Hu, Zulfiya Ibragimova, Umesh Kapur, Razan M Wafai, Swati Mehrotra. Loyola University Medical Center, Maywood, IL
Background: To do or not to do completion thyroidectomy (CT) for well differentiated thyroid cancers has been subject of debate for several years. While the procedure perse has minimal complications in experienced hands; surgery implies lifelong thyroid hormone supplementation for the patient. In addition many of the CT specimens have benign histology.
Design: A retrospective analysis of histologic findings in CT specimens was performed in patients undergoing the above procedure for a prior malignant diagnosis in lobectomy. The incidence and type of cancer in CT spceimens were assessed and conclusions drawn for rationale of the procedure.
Results: Between 1990 and 2011, 127 patients (female: 102; male: 25, age 48.6 ± 16.1 years) underwent CT. 73 of 127 patients with a diagnosis of either papillary thyroid cancer (PTC) or follicular carcinoma (FC) on lobectomy were included for review. 60 patients had PTC and 13 FC (n=11 minimally invasive and n=2 angioinvasive). 32 of 73 patients had a malignant diagnosis in CT. CT for all minimally invasive FC (n=11) showed benign histology. Of the two angioinvasive FC, one showed residual FC while the other had a microPTC in the CT specimen. The incidence was significantly higher (50%) when CT was performed for a prior diagnosis of PTC; however did not show any association with tumor size or number of tumor foci (p>0.05). CT performed for a follicular variant of PTC had a statistically significant (P<0.05) incidence of benign histology.
|Initial lobectomy||Completion thyroidectomy||%Consistency|
|Minimally invasive follicular carcinoma||11||0||0%|
|Angioinvasive follicular carcinoma||2||2||100%|
|Papillary carcinoma||60||30 (19 microPTC)||50%|
|Initial diagnosis Classification||Sub- classification||Number of patients (n)||CT diagnosis Benign||CT diagnosis Malignant||p value|