One hundred and fifteen women with IBCs (mean age 59.6 years) and two hundred and twenty-nine SDBCs (mean age 59.8 years) were included in this study. TIBCs [54 (47%)] was the most common subtype of IBCs, followed by MS [30 (26%)], FN [20 (17.4%)] and OC [11 (9.6%)]. The radiological classification of IBCs is shown in [table]1. A total of 52 IBCs (45%) developed during the second post-screening year (> 12 months), especially TIBCs [26 (48.1%)]. Other subtypes were distributed homogeneously between the first and second post-screening years (≤ 12 and > 12 months), except for OC which developed more in the first-year post-screening (≤ 12 months) [9 (81.8%)]. The IBCs frequency distribution in relation to interval time is shown in [fig]1. Overall sensitivity of our screening program calculated according to EU guidelines was equal to 78% and the average proportional incidence of IBCs between January 2018 and July 2023 was of 22%, in agreement with the ranges defined by the EU guidelines. The proportion of IBCs per 10 000 screening mammograms in the study period (IC rate/10 000) is 1.4. Parameters evaluated are shown in [table]2 and [table]3. In the logistic regression analysis, high breast density (OR = 7.55; 95% CI 3.9–14.6), high histological grade (OR = 2.41; 95% CI 1.30–4.47), ki67 overexpression (OR = 3.59; 95% CI 1.91–6.74), lymph node metastasis (OR = 4.35; 95% CI 2.04–9.28), and triple-negative phenotype (OR = 7.96; 95% CI 2.69–23.55) remained statistically significant predictors of TIBCs vs SDBCs [table]4.