Association of Human Parvovirus B19 with Papillary Thyroid Carcinoma and its Relationship with Tumor Staging and Pathologic Features

Background: Papillary thyroid carcinoma (PTC) is the most prevalent form of thyroid cancer. In some studies, parvovirus B19 (PVB19) infection was involved in the pathogenesis of thyroid diseases such as Graves’ disease, Hashimoto thyroiditis, and thyroid cancer. PVB19 induces chronic inflammation in thyroid, which can lead to carcinogenesis through the effect of inflammatory mediators. The association of PVB19 with PTC tumorigenesis is still a matter of controversy. We evaluated the correlation of PVB19 with PTC and, for the first time, pathologic features. Method: This cross-sectional retrospective study focused on the thyroid specimens of 82 patients with PTC and 77 patients with benign thyroid nodules. We conducted the present study from March 2014 to November 2017 in the hospitals affiliated with Shiraz University of Medical Sciences, Shiraz, Iran. We evaluated the presence of PVB19 DNA by nested polymerase chain reaction method in PTC, adjacent non-malignant tissues, and benign thyroid nodules. PVB19 positivity was also compared between PTC and two other groups. We further investigated the association of pathologic features and tumor staging with PVB19 positivity. Results: Of the patients, 81% were female. We detected PVB19 positivity in 9.8% of PTC specimens and 0.01 of adjacent non-malignant tissues (P=0.016). None of the benign thyroid nodule specimens had PVB19 DNA, and they were significantly different from PTC specimens (P=0.007). There was no significant correlation between PVB19 positivity and tumor stages (P=0.988) and histologic types (P=0.560). Conclusion: This research, similar to some other studies, showed a significant association between PTC and PVB19 positivity. For the first time, we showed that no significant relationship existed between PVB19 positivity and tumor stages and histologic types. Further investigations are needed to evaluate the relationship between this virus and PTC.