Risk of Malignancy from Thyroid Nodular Disease as an Element of Clinical Management of Patients with Hashimoto’s Thyroiditis

Abstract

Background: Many studies have investigated the association between chronic lymphocytic thyroiditis (CLT) and papillary thyroid carcinoma (PTC), but clinical management of this condition has never been addressed specifically, even in recent guidelines. Surprisingly the likelihood of a nodule as being cancerous in a CLT has never been explicitly expressed in terms of relative risk. Methods: This study was based on a retrospective analysis of 404 patients undergoing total thyroidectomy. Results: Sixty-nine patients (17.1%) had histological findings of true CLT, and 36.2% had concurrent PTC versus 22.6% of patients in the non-CLT group (p < 0.05), with a tumour risk in the CLT group of ×1.6 (95% CI = 1.21–1.94, likelihood ratio = +1.63). Conclusions: Patients with CLT and a nodular condition have a ×1.6 increased risk of harbouring a PTC. Moreover, these patients develop multicentric PTC more frequently, and, as a result, total thyroidectomy should always be considered.

The association between papillary thyroid carcinoma and histologically proven Hashimoto's thyroiditis: a meta-analysis

“…A total of 38 articles satisfied the eligibility criteria (3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40). The eligible studies consisted of 37 case-control studies and one cohort study, all of which were hospital based.…”

“…Loh et al (18) and Yoon et al (24) reported that PTC with HT was significantly associated with females and a lower incidence of extrathyroidal invasion and lymph node metastasis. Several studies found that PTC with HT had a tendency for multifocal involvement (3,4,26,34). In contrast, other studies failed to present any significant clinicopathologic characteristics in PTC with HT (5,25,40).…”

“…However, seven studies influenced the result of lymph node metastasis (4,7,14,29,30,37,40). In the funnel plots and the Egger's regression tests, there was no evidence of publication bias (Fig.…”

“…Eleven studies compared the occurrences of HT in PTCs and in benign thyroid diseases such as nodular hyperplasia and follicular adenoma (3,4,5,6,7,8,9,10,11,12,13). HT was found in 938 (40.5%) of 2317 PTC patients, whereas it was found in 634 (21%) of 3019 benign thyroid diseases.…”

“…Gender The incidence of HT in PTCs according to gender was compared in 23 studies (3,4,5,6,7,14,15,19,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38). HT in PTCs was observed in 1677 of 7346 (23%) female patients and in 180 of 573 (11%) male patients.…”