After a median follow up of about 11 years,
150 cancers were diagnosed on 148 patients,
of these 134/150 (89%) were Screen Detected Breast Cancers (SDBC),
while 16/150 (11%) were Interval Breast Cancer (IBC).
Of 134 SDBC 32 (24%) were detected by US alone,
95 (71%) by MMG alone or plus US,
7 (5%) by MR (Fig.3-4); 60,4% in High risk group and 17,2% in BRCA+ group; patients ages ranged from 32 to 87 years; 43% below age 50 years,
while 57% aged ≥50.
Of 32 cancers US-detected with negative mammograms 15 (47%) were asymptomatic cases,
while 17 (53%) with symptoms.
28/32 (87,5%) resulted infiltrating carcinomas and 4/32 (12,5%) in situ forms (DCIS); 20/32 (62,5%) were diagnosed in women with dense breast and 19/32 (60%) in a more favorable stage (pTis,pT1a,pT1b).
Of all Invasive lesions,
21/28 (75%) were Ductal Cancers (IDC) and 7/28 (25%) were Lobular Cancers (ILC); for each of them we have also considered their biological features and breast density (D) according to ACR criteria [4] (Fig.5).
US-only detected a large percentage of cancers in dense breasts than those diagnosed with MMG alone or MMG plus US (62,5% versus 35,5% in ACR D3-D4 group) (Fig.6).
19/32 (60%) were detected in women younger than 50 years.
Asymptomatic BC US-detected were the object of our analysis in order to confirm the great benefit of US-screening alone or in association to negative mammograms for this selected group of patients.
Of these 1/15 was DCIS and 14/15 were infiltrating carcinomas (11 IDC and 3 ILC),
12 of which (86%) in Stage I (S I) and 2 (14%) in Stage II (S II),
13/15 (87%) in a more favorable stage and small size (pTis,pT1a,pT1b) (Fig.7).
US detected 67% of cancers in asymptomatic women aged <50 years and 33% in those aged ≥50; about 60% (9/15) of non palpable BC detected in patients with mammographically dense breast.
The Relative Incremental Cancer Detection (RICD) at US in asymptomatic women over MMG detected was 24% in women aged <50 and 7% in those aged ≥50 years (Fig.8).