Advances in diagnostic practices affect thyroid cancer incidence in France

Abstract

Objective: To analyse trends in diagnostic practices of thyroid diseases and to relate them to the increase in thyroid cancer incidence in France over time. Design: From 1980 to 2000, a French retrospective multicentric (three endocrinology and three nuclear medicine centres) study of thyroid diseases was conducted on 20 consecutive unselected patients' records, sampled every 5 years in each centre. Methods: Characteristics of the population and diagnosis procedures (thyroid ultrasonography (US), radionuclide scan, cytology and hormonal measurements) were described over time. Changing trends in operated patients and in cancer prevalence were analysed as well as the impact of practices on cancer incidence. Results: The study included 471 patients (82% female, mean age 46.7, range 9-84 years), referred for nodular thyroid diseases (66.7%) or thyroid dysfunctions (33.3%). A significant increase in US (3 to 84.8%) and cytological practices (4.5 to 23%), and a decrease (89.4 to 49.6%) in radionuclide scan procedures were observed over time. Although the proportion of patients undergoing surgery remained constant (24.8%), the prevalence of cancer increased among operated patients from 12.5 to 37% (P ¼ 0.006). In a Cox's proportional hazard model stratified on the clinical characteristics of patients, only the cytological practice, regardless of its results, was significantly associated with the occurrence of cancer: relative risk (RR) ¼ 4.4 (95% confidence interval (CI): 1

Familial non-medullary thyroid carcinoma displays the features of clinical anticipation suggestive of a distinct biological entity

“…In this setting, thyroid cancer may arise from somatic mutations in the background of a long-standing familial goiter. Second, the diagnosis of thyroid cancer is particularly frequent after the introduction of neck ultrasound in clinical practice, as demonstrated by the finding that thyroid cancer is the human cancer at the largest increase in the last 10 years in USA, Australia, and Europe (Burgess 2002, Leenhardt et al 2004, AIRT Working group 2006, Davies & Welch 2006, Capezzone et al 2007. In some malignancies, as in medullary thyroid cancer without germline RET (rearranged during transfectron) proto-oncogene mutations, the definition of familial disease is based on the presence of four or more affected family members (Mulligan et al 1995).…”

Geographical correlation between incidence of benign disease and that of cancer of the thyroid among the population of the Rhône-Alpes région of France

“…The subpopulation of patients operated on for a benign disease is, however, more easily attainable. Numbers within this population clearly depend on the medical practices leading up to the surgical decision, as is the case for the apparent incidence of thyroid cancer (7).…”

Thyroid cancer: is the incidence rise abating?

“…The major part of the increase in papillary thyroid cancer incidence has been related to small tumors, less than 2 cm in diameter (1), and in recent series micropapillary cancers represent 40% of cases (1,6). The current hypothesis is that the increase in thyroid cancer incidence is mainly due to the use of more efficient diagnostic tools (7), particularly that of ultrasonography (US) and fine needle aspiration biopsy (FNAB), leading to an increased detection of small subclinical tumors. Wide variations in thyroid cancer incidence exist between countries and in the same country (8).…”