Intra- and peri-tumoral radiomics based on dynamic contrast-enhanced MRI for prediction of benign disease in BI-RADS 4 breast lesions: a multicentre study

Table 1 Histological diagnosis of all lesions including in the training and test cohorts

Histopathological type	Training cohort		Internal test cohort		External test cohort
Histopathological type	No. of lesions	%	No. of lesions	%	No. of lesions	%
Benign	197		52		22
Fibrocystic changes	100	50.8	5	9.6	7	31.8
Fibroadenoma	35	17.8	25	48.1	10	45.4
Papilloma	26	13.2	11	21.2	1	4.5
Usual ductal hyperplasia	15	7.6	2	3.8	2	9.1
Atypical ductal hyperplasia	8	4.1	2	3.8	2	9.1
Phyllodes	6	3.0	6	11.5	0	0.0
Inflammation	4	2.0	0	0.0	0	0.0
Sclerosing adenosis	2	1.0	1	1.9	0	0.0
Lobular hyperplasia	1	0.5	0	0.0	0	0.0
Malignant	319		94		30
Invasive ductal carcinoma	234	73.4	62	66.0	24	80.0
Ductal carcinoma in situ	52	16.2	19	20.2	3	10.0
Invasive lobular carcinoma	15	4.7	6	6.4	0	0.0
Invasive mucinous carcinoma	11	3.4	1	1.1	2	6.7
Other*	7	2.2	6	6.4	1	3.3

*Other: Lobular carcinoma in situ (LCIS), invasive papillary cancer; malignant phyllodes, medullary carcinoma, metastases

ISSN: 1748-717X