High Incidence of Thyroid Cancer in Southern Tuscany (Grosseto Province, Italy): Potential Role of Environmental Heavy Metal Pollution

Abstract

The incidence of thyroid cancer (TC) in Italy is one of the highest in Europe, and the reason for this is unclear. The intra-country heterogeneity of TC incidence suggests the possibility of an overdiagnosis phenomenon, although environmental factors cannot be excluded. The aim of our study is to evaluate the TC incidence trend in southern Tuscany, Italy, an area with particular geological characteristics, where the pollution and subsequent deterioration of various environmental matrices with potentially toxic elements (heavy metals) introduced from either geological or anthropogenic (human activities) sources are documented. The Tuscany cancer registry (ISPRO) provided us with the number of cases and EU standardized incidence rates (IR) of TC patients for all three provinces of southeast Tuscany (Siena, Grosseto, Arezzo) during the period of 2013–2016. In addition, we examined the histological records of 226 TC patients. We observed that the TC incidence rates for both sexes observed in Grosseto Province were significantly higher than those observed in the other two provinces. The increase was mostly due to the papillary (PTC) histotype (92% of cases), which presented aggressive variants in 37% of PTCs and tumor diameters more than 1 cm in 71.3% of cases. We demonstrated a high incidence of TC in Grosseto province, especially among male patients, that could be influenced by the presence of environmental heavy metal pollution.

Clinicopathological Assessment of Thyroid Cancer Patients Re-ferred to Imam Khomeini Hospital of Sari from Early March 2014 to Late March 2021

“…In the study of Dr.Baqer L arijani et al, papillary thyroid cancer was the most frequent pathological variant of thyroid cancer with a frequency of 79.7% [21]. The frequency of the papillary variant of thyroid cancer was 92% according to Marco Capezzone et al [22], 69% according Umesh Jayarajah's study [23], and 78.8% according to Amani Saleh Hadi's study [24]. In our study, the most common histological variant of thyroid cancer after PTC was MTC, with a frequency of 5.2%.…”

“…In our study, the most common histological variant of thyroid cancer after PTC was MTC, with a frequency of 5.2%. Marco Capezzone [22], Baqer Larijani [21], and most other studies conducted in connection with the clinic pathological evaluation of thyroid cancer have found that the most common pathological variant after PTC was FTC. Awra F.Flemban's research has revealed that the occurrence of MTC is on the rise [25].…”

Human exposure to pesticides and thyroid cancer: a worldwide systematic review of the literatures

“…There was a statistically significant correlation between Endosulfan use in 1992 and thyroid cancer IRs in 2012 ( r = 0.32; P = 0.03) and 2014 ( r = 0.32; P = 0.03) [ 25 ]. Exposure to the pesticides, may cause different cancers through various actions, including DNA damage, causing inflammation in tissues, hormonal imbalance, and turning genes on or off [ 26 ]. The thyroid hormone system has numerous sites of potential disruption by the use of multiple EDCs.…”