Cutaneous melanoma in adolescents and young adults.

BACKGROUND: Cutaneous malignant melanoma (CMM) ranks among the five most common cancers in young people in high-income countries and it features peculiar clinicopathological traits. Very few studies have addressed the quality of care and the costs for adolescents and young adults (AYA) population. OBJECTIVE: To provide a comprehensive epidemiological and clinicopathological profile of CMM in AYA. The study also addresses the cost-of-illness and the diagnostic-therapeutic performance indicators by patient age category. METHODS: This population-based cohort study included 2435 incident CMM (age range 15-65 years; age 15-39 = 394; age 40-65 = 2041), as recorded in 2015, 2017 and 2019 by the Regional Veneto Cancer Registry (Italy). Cramer's-V tested the strength of association between pairs of variables. The Kaplan-Meier method was used to test the association between age and survival rate. The clinical performance indicators were computed using the Clopper-Pearson exact method. RESULTS: In AYA patients (16.2%), CMM incidence rates increased significantly from 1990 to 2019. Low-stage CMM (p = 0.007), radial growth pattern (p = 0.026) and lower Clark levels (p = 0.007) prevailed; males had less advanced malignancies (p = 0.003), with the trunk as the most common primary site (67.5%); the lower limbs (32.6%) were the most common primary site for females (p < 0.001). Overall survival was better in AYA than adults. No significant difference was detected in the clinical management of the two age groups, with the only exception of the margin in wide local excision. The care costs were lower in AYA (€195.99 vs. €258.94, p = 0.004). CONCLUSION: In AYA patients, the CMM clinicopathological presentation shows a distinctive profile. The present results provide critical information for optimizing primary and secondary prevention strategies and for tailoring diagnostic therapeutic procedures to the peculiar profile of AYA CMM patients.

Host-related low-prevalence gastritides: Epidemiological and clinical characterization.

INTRODUCTION: A recent consensus meeting (RE.GA.IN) addressed "host-related, low-prevalence gastritis": eosinophilic (EoG), lymphocytic (Hp-pos_LyG and Hp-neg_LyG), collagenous (CollG), and granulomatous gastritis (GrG). Our study evaluates their clinico-epidemiological characteristics. MATERIALS AND METHODS: We extracted all patients with a diagnosis of EoG, LyG, CollG, and GrG from a clinicopathological database and compared their demographics, clinical and endoscopic characteristics, associated conditions, and clinical awareness to those of all other subjects in the database (controls). RESULTS: There were 1,781,005 unique patients (median age 57 years; 55.7 % female). Hispanics were overrepresented amongst those with Hp-pos_LyG. Subjects with GrG had a high prevalence of erosions and ulcers. Clinical awareness of these conditions was dismal (<1:10,000 patients). Some clinical manifestations were more common in patients with certain gastritides (e.g., vomiting and diarrhea in CollG; anemia in LyG), but none were sufficiently distinctive to suggest a clinical diagnosis. EoG was associated with EoE; LyG had a strong association with celiac disease; CollG with microscopic colitis; and GrG with Crohn disease. CONCLUSIONS: The diagnosis of these gastritides (between <1: in 1,000 and 1 in 5000 subjects) rests on histopathology. They remain poorly characterized and clinically neglected. Yet, their associations may herald other conditions: eosinophilic gastrointestinal diseases (EGID), celiac, and Crohn disease. Patients might benefit from increased detection and characterization.

Could the mitotic count improve personalized prognosis in melanoma patients?

A number of studies have indicated that the mitotic rate may be a predictive factor for poor prognosis in melanoma patients. The aim of this study was to investigate whether the mitotic rate is associated with other prognostic clinical and anatomopathological characteristics. After adjusting for other anatomopathological characteristics, we then verified the prognostic value of the number of mitoses, determining in which population subgroup this variable may have greater prognostic significance on 3-year mortality. The Veneto Cancer Registry (Registro Tumori del Veneto-RTV), a high-resolution population-based dataset covering the regional population of approximately 4.9 million residents, served as the clinical data source for the analysis. Inclusion criteria included all incident cases of invasive cutaneous malignant melanoma recorded in the RTV in 2015 (1,050 cases) and 2017 (1,205 cases) for which the number of mitoses was available. Mitotic classes were represented by Kaplan-Meier curves for short-term overall survival. Cox regression calculated hazard ratios in multivariable models to evaluate the independent prognostic role of different mitotic rate cut-offs. The results indicate that the mitotic rate is associated with other survival prognostic factors: the variables comprising the TNM stage (e.g., tumor thickness, ulceration, lymph node status and presence of metastasis) and the characteristics that are not included in the TNM stage (e.g., age, site of tumor, type of morphology, growth pattern and TIL). Moreover, this study demonstrated that, even after adjusting for these prognostic factors, mitoses per mm2 are associated with higher mortality, particularly in T2 patients. In conclusion, these findings revealed the need to include the mitotic rate in the histological diagnosis because it correlates with the prognosis as an independent factor. The mitotic rate can be used to develop a personalized medicine approach in the treatment and follow-up monitoring of melanoma patients.

Cutaneous melanoma in older patients.

BACKGROUND: In industrialized countries, the aging population is steadily rising. The incidence of cutaneous malignant melanoma (CMM) is highest in old people. This study focuses on the clinicopathological profile of CMM and indicators of diagnostic-therapeutic performance in older patients. METHODS: This retrospective population-based cohort study included 1,368 incident CMM, as recorded in 2017 by the Regional Veneto Cancer Registry (Northeast Italy). Older subjects were defined as ≥ 80, old as 65-79, and adults as < 65 years of age. The strength of association between pairs of variables was tested by Cramer's-V. Using age groups as the dependent variable, ordered logistic regression was fitted using the clinicopathological CMM profiles as covariates. In each of the three age-groups, the indicators of clinical performance were computed using the Clopper-Pearson exact method. RESULTS: Compared to patients aged younger than 80 years (1,187), CMM in older patients (181; 13.2%) featured different CMM topography, a higher prevalence of ulcers (43.3% versus 12.7%; p < 0.001), a higher Breslow index (p < 0.001), a lower prevalence of tumor-infiltrating lymphocytes (64.4% versus 76.5%, p < 0.01), and a more advanced pTNM stage at clinical presentation (p < 0.001). Elderly patients with a positive sentinel-lymph node less frequently underwent sentinel- lymph node biopsy and lymphadenectomy (60.0% versus 94.2%, and 44.4% versus 85.5%, respectively; p < 0.001). CONCLUSIONS: In older CMM patients, the clinicopathological presentation of CMM shows a distinctive profile. The present results provide critical information to optimize secondary prevention strategies and refine diagnostic-therapeutic procedures tailored to older patients.

Geographical and temporal differences in gastric and oesophageal cancer registration by subsite and morphology in Europe.

Background: Gastric and oesophageal cancers pose a serious public health concern. In 2020 a total of 189,031 incident cases (136,038 stomach, 52,993 oesophagus) and 142,508 deaths (96,997 stomach, 45,511 oesophagus) were estimated in Europe. Oesophago-gastric cancers are a heterogeneous disease, with different aetiology and epidemiology for the various topographic subsites and main histopathological types. Topography subsite and morphology is key information to allow differentiating oesophago-gastric cancers. Correct registration and coding of such variables are fundamental in allowing proper description of the epidemiology of different subsites and histopathological types of oesophago-gastric cancers. The aim of this article is to highlight geographical and temporal variability in topography and morphology of oesophago-gastric cancers observed in Europe in the considered period. Methods: Data collected in the framework of the ENCR-JRC (European Commission's Joint Research Centre) data call and feeding the European Cancer Information System (ECIS) were used to assess the variability of topography and morphology registration of gastric and oesophageal cancer in Europe in the period 1995-2014. Malignant cancers of the stomach and the oesophagus were selected following, respectively, topography codes C16 and C15 of the International Classification of Diseases for Oncology, third edition (ICD-O-3). Analyses were performed by subsite, morphology group, year, sex, and European region. Results: A total of 840,464 incident cases occurring in the period 1995-2014 - 579,264 gastric (67.2%) and 276,260 (32.8%) oesophageal carcinomas - was selected for the analysis. Data was recorded by 53 PBCRs (9 based in Northern Europe, 14 in Western Europe, 3 in Eastern Europe and 27 in Southern Europe) from 19 countries. Conclusion: A wide variability in oesophago-gastric cancers topographic subsites and histopathological types patterns was observed, with a corresponding improvement in accuracy of registration in the analysis period. PBCRs are ideally placed to guide the epidemiological evaluations of such a complex group of diseases, in collaboration with clinicians, patients and other public health stakeholders.

RE.GA.IN.: the Real-world Gastritis Initiative-updating the updates.

At the end of the last century, a far-sighted 'working party' held in Sydney, Australia addressed the clinicopathological issues related to gastric inflammatory diseases. A few years later, an international conference held in Houston, Texas, USA critically updated the seminal Sydney classification. In line with these initiatives, Kyoto Global Consensus Report, flanked by the Maastricht-Florence conferences, added new clinical evidence to the gastritis clinicopathological puzzle.The most relevant topics related to the gastric inflammatory diseases have been addressed by the Real-world Gastritis Initiative (RE.GA.IN.), from disease definitions to the clinical diagnosis and prognosis. This paper reports the conclusions of the RE.GA.IN. consensus process, which culminated in Venice in November 2022 after more than 8 months of intense global scientific deliberations. A forum of gastritis scholars from five continents participated in the multidisciplinary RE.GA.IN. consensus. After lively debates on the most controversial aspects of the gastritis spectrum, the RE.GA.IN. Faculty amalgamated complementary knowledge to distil patient-centred, evidence-based statements to assist health professionals in their real-world clinical practice. The sections of this report focus on: the epidemiology of gastritis; Helicobacter pylori as dominant aetiology of environmental gastritis and as the most important determinant of the gastric oncogenetic field; the evolving knowledge on gastric autoimmunity; the clinicopathological relevance of gastric microbiota; the new diagnostic horizons of endoscopy; and the clinical priority of histologically reporting gastritis in terms of staging. The ultimate goal of RE.GA.IN. was and remains the promotion of further improvement in the clinical management of patients with gastritis.

Low Colorectal Cancer Risk After Resection of High-Risk Pedunculated Polyps.

BACKGROUND: Post-fecal immunochemical test (FIT) colonoscopy represents a setting with an enriched prevalence of advanced adenomas. Due to an expected higher risk of colorectal cancer (CRC), postpolypectomy surveillance is recommended, generating a substantially increased load on endoscopy services. The aim of our study was to investigate postpolypectomy CRC risk in a screening population of FIT+ subjects after resection of low-risk adenomas (LRAs) or high-risk adenomas (HRAs). METHODS: We retrieved data from a cohort of patients undergoing postpolypectomy surveillance within a FIT-based CRC screening program in Italy between 2002 and 2017 and followed-up to December 2021. Main outcomes were postpolypectomy CRC incidence and mortality risks according to type of adenoma (LRA/HRA) removed at colonoscopy as well as morphology, size, dysplasia, and location of the index lesion. We adopted as comparators FIT+/colonoscopy-negative and FIT- patients. The absolute risk was calculated as the number of incident CRCs per 100,000 person-years of follow-up. We used Cox multivariable regression models to identify associations between CRC risks and patient- and polyp-related variables. RESULTS: Overall, we included 87,248 post-FIT+ colonoscopies (133 endoscopists). Of these, 42,899 (49.2%) were negative, 21,650 (24.8%) had an LRA, and 22,709 (26.0%) an HRA. After a median follow-up of 7.25 years, a total of 635 CRCs were observed. For patients with LRAs, CRC incidence (hazard ratio [HR], 1.18; 95% confidence interval [CI], 0.92-1.53) was not increased compared with the FIT+/colonoscopy-negative group, while for HRAs a significant increase in CRC incidence (HR, 1.53; 95% CI, 1.14-2.04) was found. The presence of 1 or more risk factors among proximal location, nonpedunculated morphology, and high-grade dysplasia explained most of this excess CRC risk in the HRA group (HR, 1.85; 95% CI, 1.36-2.52). Patients with only distal pedunculated polyps without high-grade dysplasia, representing 39.2% of HRA, did not have increased risk compared with the FIT- group (HR, 0.87; 95% CI, 0.59-1.28). CONCLUSIONS: CRC incidence is significantly higher in patients with HRAs diagnosed at colonoscopy. However, such excess risk does not appear to apply to patients with only distal pedunculated polyps without high-grade dysplasia, an observation that could potentially reduce the burden of surveillance in FIT programs.

The descriptive epidemiology of melanoma in Italy has changed - for the better.

A recent research project using data from a total of 40 cancer registries has provided new epidemiologic insights into the results of efforts for melanoma control in Italy between the 1990s and the last decade. In this article, the authors present a summary and a commentary of their findings. Incidence increased significantly throughout the study period in both sexes. However, the rates showed a stabilization or a decrease in men and women aged below 35 years. The risk of disease increased for successive cohorts born until 1973 (women) and 1975 (men) while subsequently tending to decline. The trend towards decreasing tumor thickness and increasing survival has continued, but a novel favorable prognostic factor has emerged since 2013 for patients - particularly for males - with thick melanoma, most likely represented by molecular targeted therapies and immune checkpoint inhibitors. Due to this, the survival gap between males and females has been filled out. In the meanwhile, and despite the incidence increase, dermatologists have not lowered their threshold to perform skin biopsy. Skin biopsy rate has increased because of the increasingly greater volume of dermatologic office visits, but the proportion of skin biopsies out of dermatologic office visits has remained constant. In summary, an important breakthrough in melanoma control in Italy has taken place. Effective interventions have been implemented across the full scope of care, which involve many large local populations - virtually the whole national population. The strategies adopted during the last three decades represent a valuable basis for further steps ahead in melanoma control in Italy.

Cost items in melanoma patients by clinical characteristics and time from diagnosis.

Background: Costs related to the care of melanoma patients have been rising over the past few years due to increased disease incidence as well as the introduction of innovative treatments. The aim of this study is to analyse CMM cost items based on stage at diagnosis, together with other diagnostic and prognostic characteristics of the melanoma. Methods: Analyses were performed on 2,647 incident cases of invasive CMM that were registered in 2015 and 2017 in the Veneto Cancer Registry (RTV). Direct melanoma-related costs per patient were calculated for each year ranging from 2 years before diagnosis to 4 years after, and were stratified by cost items such as outpatient services, inpatient drug prescriptions, hospital admissions, hospice admissions, and emergency room treatment. Average yearly costs per patient were compared according to available clinical-pathological characteristics. Lastly, log-linear multivariable analysis was performed to investigate potential cost drivers among these clinical-pathological characteristics. Findings: Overall, the average direct costs related to melanoma are highest in the first year after diagnosis (€2,903) and then decrease over time. Hospitalization costs are 8 to 16 times higher in the first year than in subsequent years, while the costs of outpatient services and inpatient drugs decrease gradually over time. When stratified by stage it is observed that the higher expenditure associated with more advanced stages of CMM is mainly due to inpatient drug use. Conclusion: The results of the present study show that grouping patients according to tumour characteristics can improve our understanding of the different cost items associated with cutaneous malignant melanoma. CMM patients experience higher costs in the first year after diagnosis due to higher hospitalization and outpatient services. Policy makers should consider overall and stage-specific annual costs when allocating resources for the management of CMM patients.

Sex Differences in Soft Tissue Sarcoma: Incidence, Clinicopathological Profile, Survival, and Costs.

Background: There are evident sex differences in the incidence of and mortality rates for several tumors. Soft tissue sarcomas (STSs) account for no more than 1% of all malignancies in adults. This study aimed to provide a comprehensive overview of the sex differences in the epidemiology of STSs and the related costs. Methods: This retrospective population-based study draws on epidemiological data regarding cases of STS collected by the cancer registry of the Italian Veneto region for the years 1990-2018. A joinpoint regression analysis was performed to identify significant changes in the trends of the standardized incidence rates in males and females. Bivariate and survival analyses were conducted to assess differences in clinicopathological characteristics and short-term mortality by sex. Direct health care costs incurred over 2 years after a diagnosis of STS were calculated, stratified by sex. Results: The incidence rates of STS at any age were higher for males; only among males the incidence rates showed a tendency to slightly increase. No significant sex differences came to light in short-term mortality or clinicopathological profile, except for the cancer site. Health care costs in the 2 years after a diagnosis of STS were not sex related. Conclusion: The STS incidence was found to be higher for males and showed a rising trend over the last three decades only for males. These findings could result from the occupational exposure to environmental mutagens mainly involving men. Sex did not affect the survival or the clinicopathological STS profile.

Cancer and Pregnancy: Estimates in Italy from Record-Linkage Procedures between Cancer Registries and the Hospital Discharge Database.

The aim of this study is to describe the frequency and trend of pregnancy-associated cancer (PAC) in Italy, an increasingly relevant phenomenon due to postponing age at childbirth. To this purpose, a population-based retrospective longitudinal study design based on cohorts of women aged 15-49 diagnosed with cancer and concomitant pregnancy is proposed. The study uses 19 population-based Cancer Registries, covering about 22% of Italy, and linked at an individual level with Hospital Discharge Records. A total of 2,861,437 pregnancies and 3559 PAC are identified from 74,165 women of the cohort with a rate of 1.24 PAC per 1000 pregnancies. The most frequent cancer site is breast (24.3%), followed by thyroid (23.9%) and melanoma (14.3%). The most frequent outcome is delivery (53.1%), followed by voluntary termination of pregnancy and spontaneous abortion (both 12.0%). The trend of PAC increased from 2003 to 2015, especially when the outcome is delivery, thus confirming a new attitude of clinicians to manage cancer throughout pregnancy. This represents the first attempt in Italy to describe PAC from Cancer Registries data; the methodology is applicable to other areas with the same data availability. Evidence from this study is addressed to clinicians for improving clinical management of women with PAC.

Indicators of clinical performance in monitoring soft tissue sarcoma management: a population-based perspective.

Background: Soft tissue sarcomas (STS) are rare malignancies which prognosis varies significantly by primary site, histological subtype, and tumor stage. Their low incidence, and the complexity of their clinico-pathological characteristics demand standardized, cancer-tailored diagnostics and therapies managed at high-volume, multidisciplinary care centers. This study evaluates the quality of STS management in north-east Italy (Veneto Region) through a list of ad hoc defined clinical indicators. Methods: This population-based study concerns all incident cases of STS in 2018 (214 cases) recorded in the adult population censored by the Veneto's regional Cancer Registry. Based on the international literature, a multidisciplinary working group of experts identified a set of indicators for monitoring the quality of diagnostic, therapeutic, and end-of-life clinical interventions. The quality of care was assessed by comparing the reference thresholds with the indicators' values achieved in clinical practice. Results: Diagnostic procedures showed poor adherence to the thresholds, with a low percentage of histological diagnoses validated by a second opinion. The indicators relating to the surgical treatment of superficial, small, low-grade STS, or of medium, high-grade STS of the head-neck, trunk, or limbs were consistent with the thresholds, while for intermediate, high-grade (large-sized, deep) and retroperitoneal STS they fell significantly below the thresholds. Conclusion: A critical evaluation of the clinical indicators allowed to uncover the procedures needing corrective action. Monitoring clinical care indicators improves cancer care, confirms the importance of managing rare cancers at highly specialized, high-volume centers, and promotes the ethical sustainability of the healthcare system.

Synchronous and metachronous multiple primary cancers in melanoma survivors: a gender perspective.

Background: Long-term survivors of cutaneous malignant melanoma (CMM) risk subsequent malignancies due to both host-related and environmental risk factors. This retrospective population-based study differentially assesses the risk of synchronous and metachronous cancers in a cohort of CMM survivors stratified by sex. Methods: The cohort study (1999-2018) included 9,726 CMM survivors (M = 4,873, F = 4,853) recorded by the cancer registry of all 5,000,000 residents in the Italian Veneto Region. By excluding subsequent CMM and non-CMM skin cancers, the incidence of synchronous and metachronous malignancies was calculated according to sex and tumor site, standardizing for age and calendar year. The Standardized Incidence Ratio (SIR) was calculated as the ratio between the number of subsequent cancers among CMM survivors and the expected number of malignancies among the regional population. Results: Irrespective of the site, the SIR for synchronous cancers increased in both sexes (SIR = 1.90 in males and 1.73 in females). Both sexes also demonstrated an excess risk for synchronous kidney/urinary tract malignancies (SIR = 6.99 in males and 12.11 in females), and women had an increased risk of synchronous breast cancer (SIR = 1.69). CMM male survivors featured a higher risk of metachronous thyroid (SIR = 3.51, 95% CI [1.87, 6.01]), and prostate (SIR = 1.35, 95% CI [1.12, 1.61]) malignancies. Among females, metachronous cancers featured higher SIR values than expected: kidney/urinary tract (SIR = 2.27, 95% CI [1.29, 3.68]), non-Hodgkin's lymphoma (SIR = 2.06, 95% CI [1.24, 3.21]), and breast (SIR = 1.46, 95% CI [1.22, 1.74]). Females had an overall increased risk of metachronous cancers in the first 5 years after CMM diagnosis (SIR = 1.54 at 6-11 months and 1.37 at 1-5 years). Conclusion: Among CMM survivors, the risk of metachronous non-skin cancers is higher than in the general population and differs significantly by sex. These results encourage sex-tailored interventions for metachronous secondary cancer prevention.

Epidemiology, pathological characteristics and survival of retroperitoneal soft­tissue sarcomas compared with non­retroperitoneal soft tissue sarcomas.

Retroperitoneal soft-tissue sarcomas (RPS) are rare forms of mesenchymal tumors that account for ~0.15% of all malignancies. The purpose of the present study was to determine the differences between RPS and non-RPS anatomopathological and clinical features and to analyze whether the hazard ratio for short-term mortality differs between patients with RPS and non-RPS, after adjusting for differences in baseline anatomopathological and clinical features. The Veneto Cancer Registry, a high-resolution population-based dataset spanning the regional population, was used as a data source for the analysis. The current analysis focuses on all incident cases of soft-tissue sarcoma recorded by the Registry from January 1, 2017 to December 31, 2018. A bivariate analysis was carried out to compare demographic and clinical characteristics in RPS and non-RPS. Short-term mortality risk was analyzed by primary tumor site. The significance of variations in survival by site group was determined using Kaplan-Meier curves and the Log-rank test. Finally, Cox regression was used to assess the hazard ratio for survival by sarcoma group. RPS accounted for 22.8% of the total sample (92 out of 404 cases). The mean age at diagnosis was 67.6 years for RPS vs. 63.4 for non-RPS; 41.3% of RPS were >150 mm vs. 5.5% for non-RPS. Stages III and IV were more prevalent in RPS (53.2 vs. 35.6%), despite the fact that, in both groups, advanced stages are the most common onset at diagnosis. Regarding surgical margins, the present study showed that R0 is the most prevalent in non-RPS (48.7%), while R1-R2 is the most frequent in patients with RPS (39.1%). The 3-year mortality rate for retroperitoneum was 42.9 vs. 25.7%. Comparing RPS and non-RPS, the multivariable Cox model showed a hazard ratio of 1.58 after adjusting for all other prognostic factors. RPS clinical and anatomopathological characteristics differ from those of non-RPS. Overall, despite adjusting for other prognostic factors, the retroperitoneum site was an independent prognostic factor associated with a worse overall survival in sarcoma patients compared with other sites.

PPIs and gastric cancer: any causal relationship?

Hydrochloric acid is crucial in gastric physiology. In 1978 cimetidine, the first H2 antagonist of histamine receptors on the gastric parietal cell was introduced into therapy, inducing acid. Lasting the years, several studies focused on the potential relationship between inducing hypo-achlorhydria and risk of developing gastric cancer. In 1988 omeprazole, the first proton pump inhibitor, entered therapy. In 1996, Kuipers underlined the danger of progression of chronic atrophic gastritis in subjects taking PPIs. In 2018, one paper from Korea and an another on from Sweden suggested a possible relationship between long-term PPI therapy and the development of gastric cancer. Over the years, several articles, meta-analyzes and population based  focused on relationship between long-term of PPI use and the onset of gastric cancer, with conflicting results. As reported, the presence of bias in the collection of cases, in particular concerning the evaluation of the H.p. status and presence of atrophic gastritis and intestinal metaplasia in subjects treated with PPI, can lead to noticeable errors in the results and conclusions, as demonstrated in the literature by exhaustive methodological studies of pharmacoepidemiology. A possible bias in the collection of case histories is due to the fact that PPIs are often administered to dyspeptic patients, among which there are patients already carriers of gastric neoplasia: the so-called inverse causality.  Literature data, amended by methodological bias (sampling errors, lack of comparative assessment of Hp status and atrophic gastritis) NOT support a causal relationship between long-term PPIs therapy and the onset of gastric cancer.

Overordering of tumor marker for outpatients revealed by performance indicators and the impact of a health policy intervention: An observational study using administrative records.

PURPOSE: The overuse of laboratory tests contributes to impair health systems effectiveness, tumor markers (TMs) being a paradigmatic example. In the present study we applied indicators of TMs appropriateness developed from administrative datasets to appraise regionwide overordering in the clinical practice. PATIENTS AND METHODS: TMs ordered to outpatients in the Veneto Region over 6 years were obtained from the eletronic Outpatients' Records of Diagnostic and Therapeutic Procedures. TMs orders were examined as aggregated data or stratified according to disease codes, gender, age, and requests per patient. TMs recommended only for specific malignancies were examined using epidemiological data obtained from Veneto Tumor Registry. RESULTS: A total of 5,821,251 TMs were ordered in 4,382,159 patients over 6 years. Overall, 3,252,389 (55.9%) TMs were ordered without appropriate disease codes (ranging from 77.0% for PSA to 17.5% for CA15.3). TM orders declined over 6 years (-13.4%), with a noticeable reduction of orders without appropriate disease codes (-21.3%). Orders decreased sharply from 2015 to 2016, after the enactment of a national Decree-Law aimed at improving appropriateness, and remained stable thereafter. However, the rate of inappropriate TMs requests still remained elevated (44.4%) in the last year of observation, with orders of TMs being much higher than expected on the basis of prevalence and incidence figures of specific malignancies. CONCLUSIONS: Indicators developed from administrative datasets were effective in assessing the overordering of TMs and the impact of interventions to improve appropriateness. The developed indicators could be considered for other diagnostic tests.