Advanced breast cancer rates in the epoch of service screening: The 400,000 women cohort study from Italy.

BACKGROUND: The objective of this study was to evaluate if mammography screening attendance is associated with a reduction in late-stage breast cancer incidence. METHODS: The cohort included over 400,000 Italian women who were first invited to participate in regional screening programmes during the 1990s and were followed for breast cancer incidence for 13 years. We obtained individual data on their exposure to screening and correlated this with total and stage-specific breast cancer incidence. Socio-economic status and pre-screening incidence data were used to assess the presence of self-selection bias. RESULTS: Overall, screening attendance was associated with a 10% excess risk of in situ and invasive breast cancer (IRR = 1.10; 95% confidence interval (CI): 1.06-1.14), which dropped to 5% for invasive cancers only (IRR = 1.05; 95% CI: 1.01-1.09). There were significant reductions among attenders for specific cancer stages; we observed a 39% reduction for T2 or larger (IRR = 0.61; 95% CI: 0.57-0.66), 19% for node positives (IRR = 0.81; 95% CI: 0.76-0.86) and 28% for stage II and higher (IRR = 0.72; 95% CI: 0.68-0.76). Our data suggest that the presence of self-selection bias is limited and, overall, invited women experienced a 17% reduction of advanced cancers compared with pre-screening rates. CONCLUSIONS: Comparing attenders' and non-attenders' stage-specific breast cancer incidence, we have estimated that screening attendance is associated with a reduction of nearly 30% for stages II+.

Human epidermal growth factor receptor 2 status and interval breast cancer in a population-based cancer registry study.

PURPOSE: To determine whether human epidermal growth factor receptor 2 (HER2) -positive status is associated with risk of breast cancer diagnosis in the interval between mammographic screening, we estimated the distribution of features of aggressive tumor behavior in a general population with newly diagnosed breast cancer and known screening status. PATIENTS AND METHODS: We evaluated all invasive breast cancers (N = 641) that were systematically collected by the Parma Province Cancer Registry and diagnosed in women age 50 to 69 years from 2004 to 2007. From this population, 292 screen-detected cancers and 48 interval cases with negative screening mammograms on expert rereading (true interval cancers) were selected for study purposes. Unconditional logistic regression adjusted for age and tumor size was used to determine whether interval cancers were associated with selected clinicobiologic characteristics. RESULTS: Tumors with a high histologic grade (odds ratio [OR], 1.8; 95% CI, 1.2 to 3.8), high proliferative rate (OR, 2.4; 95% CI, 1.2 to 4.5), negative estrogen receptor status (OR, 1.6; 95% CI, 1.1 to 3.1), or HER2-positive status (OR, 3.4; 95% CI, 1.7 to 7.1) were more likely to be diagnosed in the interval between screening. Women age less than 60 years with HER2-positive breast cancer were four times more likely to be diagnosed in the interval between screening compared with only a two-fold increased risk for older women. CONCLUSION: This population-based cancer registry study demonstrated that HER2-positive tumors account for a substantial proportion of mammographic screening failure. The distribution of biologic characteristics in screen-detected cancers differs from that observed in interval cancers and may account in part for the more aggressive behavior of interval-detected cases.

Screening mammography interpretation test: more frequent mistakes.

PURPOSE: To present the mammographic cases most commonly misinterpreted by the participants in the mammography self-test proposed by the Italian Society of Medical Radiology (SIRM) National Congress in Rimini, Italy, 2002, by analysing the findings responsible for errors, suggesting reasons for the errors, and assessing possible inadequacies in the format of the test. MATERIALS AND METHODS: The self-test was performed on the mammograms of 160 cases (32 positive and 128 negative for cancer as confirmed by histology). The mammograms had been taken in the four standard projections and placed on four multi-panel diaphanoscopes, each displaying a set of 40 cases comprising benign and malignant cases in equal proportions. The participants were given pre-printed forms on which to note down their diagnostic judgement. We evaluated a total of 134 fully-completed forms. Among these, we identified the 23 cases most frequently misread by over 15 participants in percentages varying between 40-90%. Of these cases, 10 were malignancies and 13 were negative mammograms. On review, we also assessed the diagnostic contribution of complementary investigations (not available the participants). RESULTS: The 134 fully-completed forms (all of the 40 cases) yielded a total of 5360 responses, 1180 of which (22.01%) were incorrect. Of these, 823 out of the 4288 cases expected to be negative (19.2%) were false positive, and 357 out of the 1072 cases expected to be positive (33.3%) were false negative. As regards the 23 most frequently misread cases, these were 10/32 (31.25%) mammograms positive for malignancy and 13/128 (10.15%) negative mammograms or mammograms showing benign disease. The 10 malignancies included 7 infiltrating ductal carcinomas, 1 infiltrating cribriform carcinoma, 1 infiltrating tubular carcinoma, and 1 carcinoma in situ. The 13 cases of benign disease--as established by histology or long-term follow-up--mistaken for malignancies by the test participants were fibrocystic breast disease in 5 cases, surgical scar in 1 case, ABBI scar in 1 case, radial scar in 2 cases, microcalcifications that had remained stable for years in 2 cases, focal sclero-adenosis in 1 case and sclero-elastosis in 1 case. CONCLUSIONS: The errors were due to microcalcifications, benign disease simulating a neoplasm, overlapping tissue, visibility of a lesion in one projection only, lesion site in relation to the corpus mammae, missed areas of asymmetry. Attention must be paid to these signs of focal breast disease since, if correctly evaluated, they enable the early diagnosis of low-grade carcinomas that frequently carry a favourable prognosis.