Thyroid surgical practices shaping thyroid cancer incidence in North-Eastern Italy

Thyroidectomies in Italy: A Population-Based National Analysis from 2001 to 2018

Background: The incidence of thyroid disease is generally increasing, and it is subject to major geographic variability, between and within countries. Moreover, the incidence rates and the proportion of overdiagnosis for thyroid cancer in Italy are among the highest worldwide. This study aimed to estimate population-based frequency and trends of thyroidectomies in Italy by type of surgical procedure (total/partial), indication (tumors/other conditions), sex, age, and geographical region. Materials and Methods: Age-standardized rates (ASRs) of thyroidectomies were estimated from 2001 to 2018 using the national hospital discharges database. Results: In Italy, ASRs of thyroidectomies were nearly 100 per 100,000 women in 2002-2004 and decreased to 71 per 100,000 women in 2018. No corresponding variation was shown in men (ASR 27 per 100,000 men) in the overall period. A more than twofold difference between Italian regions emerged in both sexes. The proportion of total thyroidectomies (on the sum of total and partial thyroidectomies) in the examined period increased from 78% to 86% in women and from 72% to 81% in men. Thyroidectomies for goiter and nonmalignant conditions decreased consistently throughout the period (from 81 per 100,000 women in 2002 to 49 in 2018 and from 22 to 16 per 100,000 men), while thyroidectomies for tumors increased until 2013-2014 up to 24 per 100,000 women (9 per 100,000 men) and remained essentially stable thereafter. Conclusions: The decrease in thyroidectomies for nonmalignant diseases since early 2000s in Italy may derive from the decrease of goiter prevalence, possibly as a consequence of the reduction of iodine deficiency and the adoption of conservative treatments. In a context of overdiagnosis of thyroid cancer, recent trends have suggested a decline in the diagnostic pressure with a decrease in geographic difference. Our results showed the need and also the possibility to implement more conservative surgical approaches to thyroid diseases, as recommended by international guidelines.

Temporal and geographical variations of thyroid cancer incidence and mortality in France during 1986-2015: The impact of overdiagnosis

BACKGROUND

France is among the countries showing fastest growth of thyroid cancer (TC) incidence and highest incidence rates in Europe. This study aimed to clarify the temporal and geographical variations of TC in France and to quantify the impact of overdiagnosis.

METHODS

We obtained TC incidence data in 1986-2015, and mortality data in 1976-2015, for eight French departments covering 8% of the national population, and calculated the age-standardised rates (ASR). We estimated the average annual percent changes (AAPC) of TC incidence, overall and by department and histological subtype. Numbers and proportions of TC cases attributable to overdiagnosis were estimated by department and period, based on the comparison between the shape of the age-specific curves with that observed prior to changes in diagnostic practice.

RESULTS

During 1986-2015, there were 13,557 TC cases aged 15-84 years. Large variations of TC incidence were observed across departments, with the highest ASR and the fastest increase in Isère. Papillary subtype accounted for 82.8% of the cases, and presented an AAPC of 7.0% and 7.6% in women and men, respectively. Anaplastic TC incidence decreased annually 3.0% in women and 0.8% in men. Mortality rates declined consistently for all departments. The absolute number (and proportion) of TC cases attributable to overdiagnosis grew from 1074 (66%) in 1986-1995 to 3830 (72%) in 2006-2015 in women, and varied substantially across departments.

CONCLUSIONS

Overdiagnosis plays an important role in the temporal and regional variations of TC incidence in France. Monitoring the time trends and regulating the regional healthcare practice are needed to reduce its impact.

Trends in thyroid function testing, neck ultrasound, thyroid fine needle aspiration, and thyroidectomies in North-eastern Italy

PURPOSE

Evidence of an increased diagnostic pressure on thyroid has emerged over the past decades. This study aimed to provide estimates of a wide spectrum of surveillance indicators for thyroid dysfunctions and diseases in Italy.

METHODS

A population-based study was conducted in North-eastern Italy, including 11.7 million residents (20% of the total Italian population). Prescriptions for TSH testing, neck ultrasound or thyroid fine needle aspiration (FNA), surgical procedures, and drugs for hypo- or hyperthyroidism were extracted from regional health databases. Proportions and rates of selected examinations were calculated from 2010 to 2017, overall and by sex, calendar years, age, and region.

RESULTS

Between 2010 and 2017 in North-eastern Italy, 24.5% of women and 9.8% of men received at least one TSH test yearly. In 2017, 7.1% of women and 1.5% of men were prescribed drugs for thyroid dysfunction, 94.6% of whom for hypothyroidism. Neck ultrasound examinations were performed yearly in 6.9% of women and 4.6% of men, with a nearly two-fold variation between areas. Thyroid FNA and thyroidectomies were three-fold more frequent in women (394 and 85 per 100,000) than in men (128 and 29 per 100,000) with a marked variation between areas. Both procedures decreased consistently after 2013.

CONCLUSIONS

The results of this population-based study describe recent variations over time and between surrounding areas of indicators of 'diagnostic pressure' on thyroid in North-eastern Italy. These results emphasize the need to harmonize practices and to reduce some procedures (e.g., neck ultrasound and total thyroidectomies) in certain areas.

Position paper from the Japan Thyroid Association task force on the management of low-risk papillary thyroid microcarcinoma (T1aN0M0) in adults

The incidence of thyroid carcinoma has been increasing worldwide. This is interpreted as an increase in the incidental detection of papillary thyroid microcarcinomas (PTMCs). However, mortality has not changed, suggesting overdiagnosis and overtreatment. Prospective clinical trials of active surveillance for low-risk PTMC (T1aN0M0) have been conducted in two Japanese institutions since the 1990s. Based on the favorable outcomes of these trials, active surveillance has been gradually adopted worldwide. A task force on the management of PTMC in adults organized by the Japan Thyroid Association therefore conducted a systematic review and has produced the present position paper based on the scientific evidence concerning active surveillance. This paper indicates evidence for the increased incidence of PTMC, favorable surgical outcomes for low-risk PTMC, recommended criteria for diagnosis using fine needle aspiration cytology, and evaluation of lymph node metastasis (LNM), extrathyroidal extension (ETE) and distant metastasis. Active surveillance has also been reported with a low incidence of disease progression and no subsequent recurrence or adverse events on survival if conversion surgery was performed at a slightly advanced stage. Active surveillance is a safe and valid strategy for PTMC, because it might preserve physical quality of life and reduce 10-year medical costs. However, some points should be noted when performing active surveillance. Immediate surgery is needed for PTMC showing high-risk features, such as clinical LNM, ETE or distant metastasis. Active surveillance should be performed under an appropriate medical team and should be continued for life.

Thyroid cancer in Friuli Venezia Giulia, northeastern Italy: incidence, overdiagnosis, and impact of type of surgery on survival

BACKGROUND

Incidence rates of thyroid cancer (TC) increased in the last decades worldwide. This study aimed to describe TC incidence in the Friuli Venezia Giulia (FVG) region, to estimate the quota of overdiagnosis, and to investigate the impact of surgery on long-term survival after TC diagnosis.

METHODS

TC cases reported to the FVG population-based cancer registry during 2002-2013, aged <85 years, were included. Age standardized rates (ASR) on the European population were computed, while proportion of TC overdiagnosis was estimated in comparison with expected age-specific incidence rates from published time series. Adjusted hazard ratios of death, with 95% confidence intervals, were also estimated.

RESULTS

During 2002-2013, 1701 TC cases were reported to the FVG cancer registry, with papillary TC (78.2%) as the most frequent histologic type. ASR increased from 12.4 to 16.5 in women and from 4.3 to 6.2 in men (+33.1% and +44.2%, respectively). Overdiagnosis was estimated as 79% of TC cases in women and 64% in men. Almost all TC cases (97.1%) underwent surgery, including 84.6% of women and 78.9% of men who underwent total thyroidectomy. Up to 10 years after TC diagnosis, the type of surgery did not appear to influence survival.

CONCLUSIONS

This study documented an increase in TC incidence in FVG in the last decade, with overdiagnosis accounting for a large proportion of TC diagnoses and total thyroidectomy in more than 80% of cases. These findings suggest reconsidering thyroid screening practice and aggressive therapeutic strategies, as recommended by new TC guidelines.

Is low survival for cancer in Eastern Europe due principally to late stage at diagnosis?

BACKGROUND

Cancer survival has persistently been shown to be worse for Eastern European and UK/Ireland patients than those of other European regions. This is often attributed to later stage at diagnosis. However, few stage-specific survival comparisons are available, so it is unclear whether poorer quality treatment or other factors also contribute. For the first time, European cancer registries have provided stage-at-diagnosis data to EUROCARE, enabling population-based stage-specific survival estimates across Europe.

DATA AND METHODS

In this retrospective observational study, stage at diagnosis (as TNM, condensed TNM, or Extent of Disease) was analysed for patients (≥15 years) from 15 countries grouped into 4 regions (Northern Europe: Norway; Central Europe: Austria, France, Germany, Switzerland, The Netherlands; Southern Europe: Croatia, Italy, Slovenia, and Spain; and Eastern Europe: Bulgaria, Estonia, Lithuania, Poland, and Slovakia), diagnosed with 7 malignant cancers in 2000-2007, and followed to end of 2008. A new variable (reconstructed stage) was created which used all available stage information. Age-standardised 5-year relative survival (RS) by reconstructed stage was estimated and compared between regions. Excess risks of cancer death in the 5 years after diagnosis were also estimated, taking age, sex and stage into account.

RESULTS

Low proportions of Eastern European patients were diagnosed with local stage cancers and high proportions with metastatic stage cancers. Stage-specific RS (especially for non-metastatic disease) was generally lower for Eastern European patients. After adjusting for age, sex, and stage, excess risks of death remained higher for Eastern European patients than for European patients in general.

CONCLUSIONS

Late diagnosis alone does not explain worse cancer survival in Eastern Europe: greater risk of cancer death together with worse stage-specific survival suggest less effective care, probably in part because fewer resources are allocated to health care than in the rest of Europe. We recommend that Eastern European cancer registries and other involved bodies to draw attention to poor cancer survival, so as to stimulate research and inform policies to improve outcomes.

Survival of 86,690 patients with thyroid cancer: A population-based study in 29 European countries from EUROCARE-5

BACKGROUND

Incidence rates of thyroid cancer (TC) increased in several countries during the last 30 years, while mortality rates remained unchanged, raising important questions for treatment and follow-up of TC patients. This study updates population-based estimates of relative survival (RS) after TC diagnosis in Europe by sex, country, age, period and histology.

METHODS

Data from 87 cancer registries in 29 countries were extracted from the EUROCARE-5 dataset. One- and 5-year RS were estimated using the cohort approach for 86,690 adult TC patients diagnosed in 2000-2007 and followed-up to 12/31/2008. RS trends in 1999-2007 and 10-year RS in 2005-2007 were estimated using the period approach.

RESULTS

In Europe 2000-2007, 5-year RS after TC was 88% in women and 81% in men. Survival rates varied by country and were strongly correlated (Pearson ρ = 75%) with country-specific incidence rates. Five-year RS decreased with age (in women from >95% at age 15-54 to 57% at age 75+), from 98% in women and 94% in men with papillary TC to 14% in women and 12% in men with anaplastic TC. Proportion of papillary TC varied by country and increased over time, while survival rates were similar across areas and periods. In 1999-2007, 5-year RS increased by five percentage points for all TCs but only by two for papillary and by four for follicular TC. Ten-year RS in 2005-2007 was 89% in women and 79% in men.

CONCLUSIONS

The reported increasing TC survival trend and differences by area are mainly explained by the varying histological case-mix of cases.

Incidental Papillary Thyroid Microcarcinoma in an Endemic Goiter Area

Clinical and pathological characteristics of incidental papillary thyroid microcancer cases, surgical, medical, and nuclear treatment methods, and patients' outcome were studied during follow-up period of 102 months. We studied 37 patients with incidental papillary thyroid microcancer (I-PTM). The surgical procedure was total thyroidectomy in 29 and hemithyroidectomy in 8 patients. Size, multifocality, and bilateralism of PTM foci, thyroid capsule invasion, and presence of lymphovascular invasion were histopathological parameters. We analysed adjuvant medical and nuclear treatment and patients' outcome during follow-up period of 102 (61-144) months. The prevalence rates of I-PTM were 9.4% in 395 thyroidectomy cases. Histopathological examination reported unifocal disease in 30 and multifocal disease in 7 (18%) patients. Multifocal disease was bilateral in 6 (20.1%) patients. The mean size of the PTM foci was 4.88 mm. The rate of thyroid capsule invasion was 5.4%. All patients received a suppressive dose of LT4 to achieve a low serum TSH level. Adjuvant surgical and nuclear treatment was not performed in our cases. We did not find any negative changes in blood chemistry and ultrasound imaging, and any unfavourable events as locoregional and systemic recurrence. In conclusion, diagnosis of I-PTM is common that multifocality and bilateralism appear as pathologic features. The prognosis is excellent after surgical treatment and TSH suppression. Routine adjuvant nuclear treatment is unnecessary in majority of patients.

The Impact of Diagnostic Changes on the Rise in Thyroid Cancer Incidence: A Population-Based Study in Selected High-Resource Countries

BACKGROUND

Thyroid cancer (TC) incidence is rising in many countries, but the corresponding mortality is constant or declining. Incidence increases appear largely restricted to small papillary TC in young/middle-age individuals. We compared age-specific incidence rates across countries and time periods in order to estimate the fraction of TC possibly attributable to increased surveillance of the thyroid gland (diagnostic changes) following the introduction of neck ultrasonography in the 1980s.

METHODS

We focused on high-resource countries, including four Nordic countries, England and Scotland, France, Italy, the United States, Australia, Japan, and the Republic of Korea. Before the 1970s, TC incidence in Nordic countries increased proportionally to the second power of age, consistent with the multistage model of carcinogenesis. Using this historical observation for reference, we attributed the progressive departure from linearity of the age curves in each country to an increased detection of asymptomatic disease in young/middle-age individuals. The proportion of cases attributable to diagnostic changes was estimated from the difference between observed rates and those expected using the Nordic countries as reference.

RESULTS

Diagnostic changes may account for ≥60% of TC cases diagnosed in 2003-2007 in women aged under 80 years in France, Italy, the United States, Australia, and the Republic of Korea, and approximately 50% in other assessed countries, except Japan (30%). The proportions attributable to diagnostic changes were higher in countries with largest incidence increases and were consistent across sexes, although increases were smaller and delayed in men.

CONCLUSIONS

A large proportion of TC cases diagnosed in high-resource countries in the last two decades are likely to be due to diagnostic changes. This proportion has progressively increased over time, and it is likely to grow further in the future. Since there is evidence of harm but no proof of benefit from the intense scrutiny of the thyroid, the dangers of overdiagnosis and overtreatment of TC should be urgently addressed.