Surgical complications in a population-based colorectal cancer screening program: Incidence and associated factors. / Complicaciones posquirúrgicas en un programa de cribado poblacional de cáncer colorrectal: incidencia y factores asociados.

INTRODUCTION: Colorectal cancer (CRC) screening programs produce risks, including those derived from colorectal surgeries. The objective of this analysis is to evaluate the complications associated with the surgery. PATIENTS AND METHODS: Retrospective analysis including patients who required colorectal surgery within the population-based CRC screening program in Galicia (May 2013-June 2019). We analyzed the indication for surgery and the rate of in-hospital (mildI-II, severeIII-V, Clavien-Dindo classification) and at discharge complications. We performed a multivariate analysis to determine the variables independently associated. RESULTS: In the analyzed period, 1092 patients underwent surgery (benign lesion 16.5%, pT1 CRC 18.2%, rest of CRC 64.6%) laparoscopic approach in 69.8% of the cases. In-hospital complications were detected in 19.2% of patients (mild: 13.4%; severe: 5.9%; deaths: 0.2%) and at discharge in 159 (14.6%) patients. Male sex was associated with in-hospital complications (OR: 2.0; 95%CI: 1.3-3.0). The variables associated with severe complications were: male sex (OR: 2.6; 95%CI: 1.2-5.5), tertiary hospital (OR: 0.5; 95%CI: 0.2-0.9) and ECOGI (OR: 0.2; 95%CI: 0.05-0.6). The factors associated with complications after discharge were age ≥60years (OR: 1.5; 95%CI: 1.0-2.3), rectal location (OR: 1.6; 95%CI: 1.1-2.3) and in-hospital complications (OR: 2.2; 95%CI: 1.5-3.2). CONCLUSIONS: Surgery is the main cause of morbidity and mortality associated with a CRC screening program. These results must be taken into account in the decision making of lesions that are candidates for endoscopic resection.

Overtreatment in nonmalignant lesions detected in a colorectal cancer screening program: a retrospective cohort study.

BACKGROUND: Although colorectal cancer (CRC) screening programs reduce CRC incidence and mortality, they are associated with risks in healthy subjects. However, the risk of overtreatment and overdiagnosis has not been determined yet. The aim of this study was to report the surgery rates in patients with nonmalignant lesions detected within the first round of a fecal immunochemical test (FIT) based CRC screening program and the factors associated with it. METHODS: We included in this analysis all patients with nonmalignant lesions detected between May 2013 and June 2019 in the Galician (Spain) CRC screening program. We calculated surgery rate according to demographic variables, the risk classification according to the colonoscopy findings (European guidelines for quality assurance), the endoscopist's adenoma detection rate (ADR) classified into quartiles and the hospital's complexity level. We determined which variables were independently associated with surgery rate and expressed the association as Odds Ratio and its 95% confidence interval (CI). RESULTS: We included 15,707 patients in the analysis with high (19.9%), intermediate (26.9%) low risk (23.3%) adenomas and normal colonoscopy (29.9%) detected in the analyzed period. Colorectal surgery was performed in 162 patients (1.03, 95% CI 0.87-1.19), due to colonoscopy complications (0.02, 95% CI 0.00-0.05) and resection of colorectal benign lesions (1.00, 95% CI 0.85-1.16). Median hospital stay was 6 days with 17.3% patients developing minor complications, 7.4% major complications and one death. After discharge, complications developed in 18.4% patients. In benign lesions, an endoscopic resection was performed in 25.4% and a residual premalignant lesion was detected in 89.9%. The variables independently associated with surgery in the multivariable analysis were age (≥60 years = 1.57, 95% CI 1.11-2.23), sex (female = 2.10, 95% CI 1.52-2.91), the European guidelines classification (high risk = 67.94, 95% CI 24.87-185.59; intermediate risk = 5.63, 95% CI 1.89-16.80; low risk = 1.43; 95% CI 0.36-5.75), the endoscopist's ADR (Q4 = 0.44, 95% CI 0.28-0.68; Q3 = 0.44, 95% CI 0.27-0.71; Q2 = 0.71, 95% CI 0.44-1.14) and the hospital (tertiary = 0.54, 95% CI 0.38-0.79). CONCLUSIONS: In a CRC screening program, the surgery rate and the associated complications in patients with nonmalignant lesions are low, and related to age, sex, endoscopic findings, endoscopist's ADR and the hospital's complexity.

Colonoscopy versus fecal immunochemical testing in colorectal-cancer screening.

BACKGROUND: Colonoscopy and fecal immunochemical testing (FIT) are accepted strategies for colorectal-cancer screening in the average-risk population. METHODS: In this randomized, controlled trial involving asymptomatic adults 50 to 69 years of age, we compared one-time colonoscopy in 26,703 subjects with FIT every 2 years in 26,599 subjects. The primary outcome was the rate of death from colorectal cancer at 10 years. This interim report describes rates of participation, diagnostic findings, and occurrence of major complications at completion of the baseline screening. Study outcomes were analyzed in both intention-to-screen and as-screened populations. RESULTS: The rate of participation was higher in the FIT group than in the colonoscopy group (34.2% vs. 24.6%, P<0.001). Colorectal cancer was found in 30 subjects (0.1%) in the colonoscopy group and 33 subjects (0.1%) in the FIT group (odds ratio, 0.99; 95% confidence interval [CI], 0.61 to 1.64; P=0.99). Advanced adenomas were detected in 514 subjects (1.9%) in the colonoscopy group and 231 subjects (0.9%) in the FIT group (odds ratio, 2.30; 95% CI, 1.97 to 2.69; P<0.001), and nonadvanced adenomas were detected in 1109 subjects (4.2%) in the colonoscopy group and 119 subjects (0.4%) in the FIT group (odds ratio, 9.80; 95% CI, 8.10 to 11.85; P<0.001). CONCLUSIONS: Subjects in the FIT group were more likely to participate in screening than were those in the colonoscopy group. On the baseline screening examination, the numbers of subjects in whom colorectal cancer was detected were similar in the two study groups, but more adenomas were identified in the colonoscopy group. (Funded by Instituto de Salud Carlos III and others; ClinicalTrials.gov number, NCT00906997.).

Mammographic and clinical characteristics of different phenotypes of screen-detected and interval breast cancers in a nationwide screening program.

In the context of a population-based screening program, we aimed to evaluate the major mammographic features and clinicopathological characteristics of breast tumors at diagnosis and the associations between them, focusing on tumors with the worst prognosis. We analyzed cancers diagnosed in a cohort of 645,764 women aged 45-69 years participating in seven population-based screening programs in Spain, between January 1, 2000 and December 31, 2006 and followed up until June 2009. We included all interval cancers and a sample of screen-detected cancers, whether invasive or in situ. We compared tumor-related information and breast density for different phenotypes (Triple-negative (TN), HER2+, Luminal B and Luminal A) in screen-detected and interval cancers. We used Chi-square or Fisher's exact test to compare major mammographic features of invasive versus in situ tumors, of screen-detected versus interval cancers, and of different types of interval cancers. We included 2582 tumors (1570 screen-detected and 1012 interval cancers). There were significant differences in the distribution of most clinicopathological variables between screen-detected and interval cancers. Invasive TN interval tumors were more common than other phenotypes in breasts with low mammographic density; three-quarters of these tumors presented as masses without associated calcifications. HER2+ tumors were more common in denser breasts and were associated with calcifications and multifocality. Architectural distortion was more common in Luminal A and Luminal B tumors. Certain radiologic findings are associated with pre-invasive lesions; these differ among invasive tumor phenotypes. We corroborate that TN and HER2+ cancers have distinctive appearances also in the context of population-based screening programs. This information can be useful for establishing protocols for diagnostic strategies in screening units.

Walking, biking or sport: how Spanish women attending breast cancer screening meet physical activity recommendations?

BACKGROUND: The aim is to analyse physical activity (PA), the fulfillment recommendation of at least 150 min of moderate PA, through walking/biking (W&B), sport, both types of PA and the factors associated with inactivity by Spanish women who attended breast cancer screening programmes. METHODS: The DDM-Spain is a multicentre cross-sectional study involving 3584 women, aged 45-68, attending screening in seven Spanish cities. Data were collected using a questionnaire, including age, socio-demographic and lifestyle characteristics, family burden and PA. PA was converted into metabolic equivalent of task (METs), categorized as low ≤ 600 METs min per week (m/w), moderate 600-3000 METs m/w and high ≥ 3000 METs m/w. A multivariate logistic regression was performed to identify variables associated with inactivity for each type of PA. RESULTS: No women achieved a high level of PA through sport. 79.2% achieved a high or moderate level of PA by W&B. Lack of sport was associated with being overweight (odds ratio OR = 1.31; 95% confidence interval CI: 1.06 to 1.62), body mass index (BMI) ≥ 30 (OR = 1.85; 95% CI: 1.44 to 2.38), smoking (OR = 1.56; 95% CI: 1.22 to 2.00) and living with a disabled person (OR = 1.64; 95% CI: 1.0 to 2.81), whereas enough sport practice was associated with higher educational or socio-economic level (SEL). Regarding W&B, inactivity was associated with BMI ≥ 30 (OR = 1.91; 95% CI: 1.49 to 2.45) and living with someone >74 (OR = 1.96; 95% CI: 1.48 to 2.58). Inactivity for both types of exercise was associated with a BMI ≥ 30 (OR = 2.13; 95% CI: 1.63 to 2.8), smoking (OR = 1.41; 95% CI: 1.09 to 1.81) and living with someone >74 (OR = 1.69; 95% CI: 1.24 to 2.28). CONCLUSIONS: Family burden and BMI ≥ 30 are inversely associated with both types of PA. W&B is the most common type of PA regardless of educational and SEL.

Tumor phenotype and breast density in distinct categories of interval cancer: results of population-based mammography screening in Spain.

INTRODUCTION: Interval cancers are tumors arising after a negative screening episode and before the next screening invitation. They can be classified into true interval cancers, false-negatives, minimal-sign cancers, and occult tumors based on mammographic findings in screening and diagnostic mammograms. This study aimed to describe tumor-related characteristics and the association of breast density and tumor phenotype within four interval cancer categories. METHODS: We included 2,245 invasive tumors (1,297 screening-detected and 948 interval cancers) diagnosed from 2000 to 2009 among 645,764 women aged 45 to 69 who underwent biennial screening in Spain. Interval cancers were classified by a semi-informed retrospective review into true interval cancers (n = 455), false-negatives (n = 224), minimal-sign (n = 166), and occult tumors (n = 103). Breast density was evaluated using Boyd's scale and was conflated into: <25%; 25 to 50%; 50 to 75%; >75%. Tumor-related information was obtained from cancer registries and clinical records. Tumor phenotype was defined as follows: luminal A: ER+/HER2- or PR+/HER2-; luminal B: ER+/HER2+ or PR+/HER2+; HER2: ER-/PR-/HER2+; triple-negative: ER-/PR-/HER2-. The association of tumor phenotype and breast density was assessed using a multinomial logistic regression model. Adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. All statistical tests were two-sided. RESULTS: Forty-eight percent of interval cancers were true interval cancers and 23.6% false-negatives. True interval cancers were associated with HER2 and triple-negative phenotypes (OR = 1.91 (95% CI:1.22-2.96), OR = 2.07 (95% CI:1.42-3.01), respectively) and extremely dense breasts (>75%) (OR = 1.67 (95% CI:1.08-2.56)). However, among true interval cancers a higher proportion of triple-negative tumors was observed in predominantly fatty breasts (<25%) than in denser breasts (28.7%, 21.4%, 11.3% and 14.3%, respectively; <0.001). False-negatives and occult tumors had similar phenotypic characteristics to screening-detected cancers, extreme breast density being strongly associated with occult tumors (OR = 6.23 (95% CI:2.65-14.66)). Minimal-sign cancers were biologically close to true interval cancers but showed no association with breast density. CONCLUSIONS: Our findings revealed that both the distribution of tumor phenotype and breast density play specific and independent roles in each category of interval cancer. Further research is needed to understand the biological basis of the overrepresentation of triple-negative phenotype among predominantly fatty breasts in true interval cancers.

Participation and detection rates by age and sex for colonoscopy versus fecal immunochemical testing in colorectal cancer screening.

PURPOSE: To compare two strategies for colorectal cancer screening: one-time colonoscopy versus fecal immunochemical testing (FIT) (and colonoscopy for positive) every 2 years, in order to determine which strategy provides the highest participation and detection rates in groups of sex and age. METHODS: This analysis was performed with data from the first screening round within the COLONPREV study, a population-based, multicenter, nationwide trial carried out in Spain. Several logistic regression models were applied to identify the influence of the screening test on participation rates and detection of proximal and distal neoplasms, as well to identify the influence of age and sex: women aged 50-59 years, women aged 60-69 years, men aged 50-59 years, and men aged 60-69 years. RESULTS: Participation was higher in women than in men, especially among women aged 50-59 years (25.91 % for colonoscopy and 35.81 % for FIT). Crossover from colonoscopy to FIT was higher among women than men, especially among those aged 60-69 years (30.37 %). In general, detection of any neoplasm and advanced adenoma was higher with colonoscopy than with FIT, but no significant differences were found between the two strategies for colorectal cancer detection. Detection of advanced adenoma in both arms was lower in women [specifically in women aged 50-59 years (OR 0.31; 95 % CI 0.25-0.38) than in men aged 60-69 years]. Women aged 50-59 years in the colonoscopy arm had a higher probability of detection of advanced adenoma (OR 4.49; 95 % CI 3.18-6.35), as well as of detection of neoplasms in proximal and distal locations (proximal OR 19.34; 95 % CI 12.07-31.00; distal OR 11.04; 95 % CI 8.13-15.01) than women of the same age in the FIT arm. These differences were also observed in the remaining groups but to a lesser extent. CONCLUSION: Women were more likely to participate in a FIT-based strategy, especially those aged 50-59 years. The likelihood of detection of any neoplasm was higher in the colonoscopy arm for all the population groups studied, especially in women aged 50-59 years. Distinct population groups should be informed of the benefits of each screening strategy so that they may take informed decisions.

Impact of intermediate mammography assessment on the likelihood of false-positive results in breast cancer screening programmes.

OBJECTIVES: Breast cancer screening is offered to 100% of the target population in Spain and intermediate mammograms (IMs) are sometimes indicated. This study was aimed at analysing the frequency of IMs, the factors determining their recommendation, and their impact on the risk of false-positive results and the detection rate. METHODS: Data from 3,471,307 mammograms from Spanish breast cancer screening programmes were included. RESULTS: 3.36% of the mammograms were IMs. The factors associated with the use of IMs were age, initial screening, previous invasive tests, a familial history of breast cancer and use of hormone replacement therapy. In screening episodes with an IM, the probability of a false-positive result was 13.74% (95% CI: 13.43-14.05), almost double that in episodes without IMs (6.02%, 95% CI 5.99-6.05). In young women with previous invasive procedures, a familial history of breast cancer or hormone replacement therapy use who were undergoing their initial screen, this probability was lower when IMs were performed. IMs always increased the detection rate. CONCLUSIONS: The factors prompting IMs should be characterised so that radiologists can systematise their recommendations according to the presence of the factors maximising the benefits and minimising the adverse effects of this procedure. KEY POINTS: Intermediate mammograms in breast screening offer potential benefits but also disadvantages. Intermediate mammograms increase the false-positive rate except in specific groups. Intermediate mammograms reduce the false-positive rate in younger women and initial screens. Intermediate mammograms also reduce false-positive results in women with personal risk factors. Intermediate mammograms increase cancer detection mainly in women without risk factors.

Effect of false-positive results on reattendance at breast cancer screening programmes in Spain.

BACKGROUND: Mammography is the only breast screening method, we are aware of today, which is able to reduce mortality from breast cancer. Nevertheless, this procedure carries an inherent risk of false-positive screening mammogram. The association between these results and reattendance at the next scheduled screening mammogram is controversial. The aim of this study was to examine the effect of a false-positive screening mammogram and women's characteristics on reattendance in eight regional population-based breast cancer screening programmes in Spain. METHODS: This study included 1 383 032 women aged 44-67 years who were initially screened for breast cancer between 1990 and 2004. To investigate factors associated with reattendance, logistic regression models were used. RESULTS: The mean age of women at first screening was 53.6 years (SD = 6.1 years). Of 120 800 women with a false-positive screening mammogram, 78.3% returned for a subsequent screening mammogram compared with 81.9% of those with a negative result (P < 0.001). Multivariate analysis showed that women with a false-positive result at first screening mammogram were less likely to reattend (OR = 0.71; 95% CI 0.70-0.73) and that the likelihood was lower in those who had undergone invasive additional tests (OR = 0.56; 95% CI 0.53-0.59). CONCLUSION: A false-positive screening mammogram in the first screening negatively affected attendance at the subsequent screening. The results of this study could be useful to improve the screening process and to increase women's compliance.

Effect of start age of breast cancer screening mammography on the risk of false-positive results.

OBJECTIVE: To estimate the false-positive (FP) risk according to the start age of mammography screening (45-46 or 50-51 years). METHOD: Data from eight regions of the Spanish breast cancer screening programme from 1990 to 2006 were included (1,565,364 women). Discrete time-hazard models were used to ascertain the effect of age and time-related, programme-related and personal variables on FP leading to any further procedure and to invasive procedures (FPI). In a subset we estimated the differential FP risk of starting screening at 45-46 years (175,656 women) or 50-51 (251,275). RESULTS: A start age of 45-46 versus 50-51 years increased both FP (OR=1.20; 95%CI: 1.13-1.26) and FPI risks (OR=1.43 (95%CI: 1.18-1.73).Other factors increasing FP risk were premenopausal status (FP OR=1.26; 95%CI: 1.23-1.29 and FPI OR=1.22; 95%CI: 1.13-1.31), prior invasive procedures (FP OR=1.52; 95%CI: 1.47-1.57 and FPI (OR=2.08; 95%CI: 1.89-2.28) and family history (FP OR=1.16; 95%CI: 1.12-1.20 and FPI OR=1.26; 95%CI: 1.13-1.41). FP risk was increased by double reading (OR=1.36; 95%CI: 1.23-1.51) and FPI risk by double views (OR=1.34; 95%CI: 1.18-1.52). Both the cumulative FP and FPI risks were higher in women commencing screening at 45-46 years versus 50-51 years (33.30% versus 20.39% and 2.68% versus 1.76%). CONCLUSIONS: Starting screening earlier increases the cumulative risk of FP and FPI.

pT1 Colorectal Cancer Detected in a Colorectal Cancer Mass Screening Program: Treatment and Factors Associated with Residual and Extraluminal Disease.

The aim of this study is to describe the treatment of pT1 colorectal cancer (CRC) in a mass screening program, the surgery-related complications and the factors associated with residual disease after endoscopic resection and extraluminal disease after surgery. We included in this retrospective analysis all the pT1 CRC detected in the Galician CRC screening program between May 2013 and June 2019. We determined which variables were independently associated with the outcomes of the study through a multivariable logistic regression analysis. We included 370-354 pT1 N0(X), 16 pT1N1- out of the 971 CRC detected; 277 (74.9%) were resected endoscopically and 162 (43.8%) were not referred to surgery. There were surgical complications in 30.7% and 16.3% of the patients during hospitalization and after discharge. Residual disease was detected in 12 (4.3%) after endoscopic resection and extraluminal disease in 18 (8.6%) patients after surgery. The variables independently associated with initial endoscopic resection were a pedunculated morphology (OR 33.1, 95% CI 4.3-254), a diameter ≥ 20 mm (OR 3.94, 95% CI 1.39-11.18) and a Site-Morphology-Size-Access score < 9 (OR 428, 95% CI 42-4263). The variables related with surgery rescue were a piecemeal resection (OR 4.48, 95% CI 1.48-13.6), an infiltrated/nonevaluable resection border (OR 7.44, 95% CI 2.12-26.0), a non-well-differentiated histology (OR 4.76, 95% CI 1.07-20.0), vascular infiltration (OR 8.24, 95% CI 2.72-25.0) and a Haggitt 4 infiltration of the submucosa (OR 5.68, 95% CI 2.62-12.3). Residual disease after endoscopic resection was associated with an infiltrated/nonevaluable resection border (OR 34.9, 95% CI 4.08-298), a non-well-differentiated histology (OR 6.67, 95% CI 1.05-50.0), and the vascular infiltration of the submucosa (OR 7.61, 95% CI 1.55-37.4). The variables related with extraluminal disease after surgical resection were no endoscopic resection (OR 4.34, 95% CI 1.26-14.28), a non-well-differentiated histology (OR 4.35, 95% CI 1.39-14.29) and the lymphatic infiltration of the submucosa (OR 4.8, 95% CI 1.32-17.8). In a CRC screening program, although most of pT1 CRC are candidates for endoscopic treatment, surgery is a safe procedure. We have defined some easy to evaluate variables that can be used in the decision-making process.

Impact of risk factors on different interval cancer subtypes in a population-based breast cancer screening programme.

BACKGROUND: Interval cancers are primary breast cancers diagnosed in women after a negative screening test and before the next screening invitation. Our aim was to evaluate risk factors for interval cancer and their subtypes and to compare the risk factors identified with those associated with incident screen-detected cancers. METHODS: We analyzed data from 645,764 women participating in the Spanish breast cancer screening program from 2000-2006 and followed-up until 2009. A total of 5,309 screen-detected and 1,653 interval cancers were diagnosed. Among the latter, 1,012 could be classified on the basis of findings in screening and diagnostic mammograms, consisting of 489 true interval cancers (48.2%), 235 false-negatives (23.2%), 172 minimal-signs (17.2%) and 114 occult tumors (11.3%). Information on the screening protocol and women's characteristics were obtained from the screening program registry. Cause-specific Cox regression models were used to estimate the hazard ratios (HR) of risks factors for interval cancer and incident screen-detected cancer. A multinomial regression model, using screen-detected tumors as a reference group, was used to assess the effect of breast density and other factors on the occurrence of interval cancer subtypes. RESULTS: A previous false-positive was the main risk factor for interval cancer (HR = 2.71, 95%CI: 2.28-3.23); this risk was higher for false-negatives (HR = 8.79, 95%CI: 6.24-12.40) than for true interval cancer (HR = 2.26, 95%CI: 1.59-3.21). A family history of breast cancer was associated with true intervals (HR = 2.11, 95%CI: 1.60-2.78), previous benign biopsy with a false-negatives (HR = 1.83, 95%CI: 1.23-2.71). High breast density was mainly associated with occult tumors (RRR = 4.92, 95%CI: 2.58-9.38), followed by true intervals (RRR = 1.67, 95%CI: 1.18-2.36) and false-negatives (RRR = 1.58, 95%CI: 1.00-2.49). CONCLUSION: The role of women's characteristics differs among interval cancer subtypes. This information could be useful to improve effectiveness of breast cancer screening programmes and to better classify subgroups of women with different risks of developing cancer.

[Breast cancer screening: characteristics and results of the Spanish programs]. / Programas de detección precoz de cáncer de mama en España: características y principales resultados.

BACKGROUND AND OBJECTIVE: To describe national and regional indicators of process and outcome of breast cancer screening programs in Spain. PATIENTS AND METHOD: Overall results and broken down by regions are studied for the period 2007-2008. Outcome indicators (participation, cancer detection rate and characteristics of tumors detected) and process indicators (and intermediate mammograms), classified by types of women screened (initial and consequent regular and irregular) and age groups, are analyzed. Results are compared with reference values established in the European Guidelines. RESULTS: Breast cancer screening coverage is 100% in the country. The overall participation was 69.68% with an adherence of 91.35%. Further assessments of any procedure were performed in 4.93% and invasive further assessments in 0.66%. Intermediate mammograms were indicated in 3.56%. The detection rate was 3.49‰ (5.35‰ age-adjusted); 14.29% of the tumors were intraductal. The 29.49% of the invasive tumors were≤1cm in diameter with 62.22% showing no axillary lymph node involvement. CONCLUSIONS: Despite the variability evident in the data provided by the different autonomous communities and the need to improve the homogeneity of information systems as a whole, the assessed indicators meet the standards specified in the European guidelines.

Trends in detection of invasive cancer and ductal carcinoma in situ at biennial screening mammography in Spain: a retrospective cohort study.

BACKGROUND: Breast cancer incidence has decreased in the last decade, while the incidence of ductal carcinoma in situ (DCIS) has increased substantially in the western world. The phenomenon has been attributed to the widespread adaption of screening mammography. The aim of the study was to evaluate the temporal trends in the rates of screen detected invasive cancers and DCIS, and to compare the observed trends with respect to hormone replacement therapy (HRT) use along the same study period. METHODS: Retrospective cohort study of 1,564,080 women aged 45-69 years who underwent 4,705,681 screening mammograms from 1992 to 2006. Age-adjusted rates of screen detected invasive cancer, DCIS, and HRT use were calculated for first and subsequent screenings. Poisson regression was used to evaluate the existence of a change-point in trend, and to estimate the adjusted trends in screen detected invasive breast cancer and DCIS over the study period. RESULTS: The rates of screen detected invasive cancer per 100.000 screened women were 394.0 at first screening, and 229.9 at subsequent screen. The rates of screen detected DCIS per 100.000 screened women were 66.8 at first screen and 43.9 at subsequent screens. No evidence of a change point in trend in the rates of DCIS and invasive cancers over the study period were found. Screen detected DCIS increased at a steady 2.5% per year (95% CI: 1.3; 3.8), while invasive cancers were stable. CONCLUSION: Despite the observed decrease in breast cancer incidence in the population, the rates of screen detected invasive cancer remained stable during the study period. The proportion of DCIS among screen detected breast malignancies increased from 13% to 17% throughout the study period. The rates of screen detected invasive cancer and DCIS were independent of the decreasing trend in HRT use observed among screened women after 2002.

[Current status of research in breast cancer screening in Spain: implications for prevention]. / Situación de la investigación en el cribado de cáncer de mama en España: implicaciones para la prevención.

OBJECTIVE: The consolidation of breast cancer screening programs, with full coverage of the target population in all Spanish regions, has encouraged the beginning of a joint research strategy. This strategy aims to improve the effectiveness of breast cancer screening by gathering information from distinct screening programs. METHODS: A retrospective cohort with information on over 1.5 million screened women was constructed to evaluate risk factors for a false-positive result. The impact of the change from digital mammography to screen-film mammography was evaluated, while results for interval cancers and false negatives are currently being studied. RESULTS: The results are highly useful from the perspective of public health, as they can be used to identify and improve the information provided to women with a higher risk of experiencing an adverse effect. These results will also be helpful to identify screening program-related characteristics and women's personal characteristics, which will allow better prevention strategies to be developed. CONCLUSIONS: The results obtained will be included in mathematical models currently under development to evaluate the efficiency of breast cancer screening. These models could be highly useful to provide information and guide clinical and health policy decisions on cancer prevention and control.

Programas de detección precoz de cáncer de mama en España: características y principales resultados / Breast cancer screening: characteristics and results of the Spanish programs

Fundamento y objetivo: Describir a nivel nacional y por Comunidades Autónomas (CCAA) indicadores de proceso y resultado de los programas de cribado de cáncer de mama españoles. Pacientes y método: Se describen los resultados globales y desagregados por CCAA correspondientes al período 2007-2008, de resultado (participación, tasa de detección de cáncer y características de los tumores detectados) y de proceso (pruebas adicionales y revisiones intermedias), clasificados por tipos de mujeres cribadas (iniciales y sucesivas regulares e irregulares) y por grupos de edad. Los resultados se comparan con los valores de referencia establecidos en la Guía Europea. Resultados: La cobertura del cribado de cáncer de mama es del 100% en el territorio nacional. La participación global fue del 69,68%, con una adherencia del 91,35%. Se realizaron pruebas adicionales de cualquier tipo en el 4,93% de mujeres y de carácter invasivo en un 0,66%. En el 3,56% se indicó una revisión intermedia. La tasa de detección fue del 3,49‰ (5,35‰ ajustada por edad). Un 14,29% de los tumores fueron intraductales. El 29,49% de los invasivos resultaron ≤ 1 cm y un 62,22% no presentaron afectación ganglionar axilar. Conclusiones: A pesar de evidenciarse la variabilidad en los datos aportados por las distintas CCAA, así como la necesidad de mejorar la homogeneidad de los sistemas de información, en su conjunto, los indicadores evaluados de los programas de cribado de cáncer de mama alcanzan los estándares especificados en las directrices europeas (AU)

Background and objective: To describe national and regional indicators of process and outcome of breast cancer screening programs in Spain. Patients and method: Overall results and broken down by regions are studied for the period 2007-2008. Outcome indicators (participation, cancer detection rate and characteristics of tumors detected) and process indicators (and intermediate mammograms), classified by types of women screened (initial and consequent regular and irregular) and age groups, are analyzed. Results are compared with reference values established in the European Guidelines. Results: Breast cancer screening coverage is 100% in the country. The overall participation was 69.68% with an adherence of 91.35%. Further assessments of any procedure were performed in 4.93% and invasive further assessments in 0.66%. Intermediate mammograms were indicated in 3.56%. The detection rate was 3.49‰ (5.35‰ age-adjusted); 14.29% of the tumors were intraductal. The 29.49% of the invasive tumors were ≤ 1 cm in diameter with 62.22% showing no axillary lymph node involvement. Conclusions: Despite the variability evident in the data provided by the different autonomous communities and the need to improve the homogeneity of information systems as a whole, the assessed indicators meet the standards specified in the European guidelines (AU)