| Literature DB >> 33948701 |
Suzanne L van Winkel1, Alejandro Rodríguez-Ruiz2, Linda Appelman3, Albert Gubern-Mérida2, Nico Karssemeijer3,2, Jonas Teuwen3,4, Alexander J T Wanders5, Ioannis Sechopoulos3,6, Ritse M Mann7,8.
Abstract
OBJECTIVES: Digital breast tomosynthesis (DBT) increases sensitivity of mammography and is increasingly implemented in breast cancer screening. However, the large volume of images increases the risk of reading errors and reading time. This study aims to investigate whether the accuracy of breast radiologists reading wide-angle DBT increases with the aid of an artificial intelligence (AI) support system. Also, the impact on reading time was assessed and the stand-alone performance of the AI system in the detection of malignancies was compared to the average radiologist.Entities:
Keywords: Artificial intelligence (AI); Breast cancer; Digital breast tomosynthesis (DBT); Mammography; Mass screening
Mesh:
Year: 2021 PMID: 33948701 PMCID: PMC8523448 DOI: 10.1007/s00330-021-07992-w
Source DB: PubMed Journal: Eur Radiol ISSN: 0938-7994 Impact factor: 5.315
Fig. 1Flow of women through the study, from data collection until data selection for the observer evaluation
Truth status on a case, breast, and lesion level of the cohort of 240 cases used in the observer evaluation
| Truth | Cases | Breasts | Lesions |
|---|---|---|---|
| Normal | 110/240 (46%) | 334/480 (70%) | n/a |
| Benign* | 65/240 (27%) | 75/480 (16%) | 86 |
| Malignant** | 65/240 (27%) | 71/480 (14%) | 85 |
*Within the benign breasts, six are the contralateral breast to a malignant breast. Two breasts containing a malignant and a benign lesion were regarded as malignant at the breast level. Four cases have benign lesions in both breasts. Seven breasts have two benign lesions and one breast has three benign lesions
**Six cases have breast cancer lesions in both breasts
Characteristics of the cohort of 240 cases used in the observer evaluation, including the pathological and morphological characteristics of the lesions.
| Cases | 240 |
|---|---|
| Mean age in years (range) | 56 (30–81) |
| Median compressed breast thickness in mm (range) | 59 (27–99) |
| BI-RADS breast density | A: 27/240 (11%) B: 93/240 (39%) C: 105/240 (44%) D: 15/240 (6%) |
| Median size in mm of malignant lesions (range) | 15 (3–116) |
| Morphology of the key findings of malignant breasts | Mass: 40/71 (56%) Calcifications: 17/71 (24%) Mass + calcifications: 2/71 (3%) Architectural distortion: 8/71 (11%) Mass + architectural distortion: 1/71 (1%) Asymmetric density: 3/71 (4%) |
| Morphology of the key findings of benign breasts | Mass: 26/75 (35%) Calcifications: 38/75 (51%) Mass + calcifications: 2/75 (3%) Architectural distortion: 4/75 (5%) Asymmetric density: 4/75 (5%) Mass + asymmetric density: 1/75 (1%) |
| Histology of malignant breasts | IDC (invasive ductal ca.): 32/71 (45%) ILC (invasive lobular ca.): 7/71 (10%) DCIS (ductal ca. in situ): 15/71 (21%) IDC + DCIS: 11/71 (15%) IDC + other invasive type: 4/71 (6%) Invasive papilloma: 1/71 (1%) Invasive medullar ca.: 1/71 (1%) |
| Histology of benign breasts | Atypical ductal hyperplasia: 22/75 (29%) Fibroadenoma: 12/75 (16%) Adenosis: 6/75 (8%) Fibrocystic changes: 5/75 (7%) Breast cysts: 4/75 (5%) Fat necrosis: 3/75 (4%) Papilloma: 3/75 (4%) Apocrine metaplasia: 2/75 (3%) Others: 18/75 (24%) |
Fig. 2Average receiver operating characteristic curves (ROC) of the radiologists reading breast tomosynthesis (DBT) unaided and reading DBT exams with AI support concurrently. The difference in ROC area under the curve was significant, + 0.03, p = 0.0025
Differences in the area under the receiver operating characteristic curve (AUC) and reading time for each radiologist between reading breast tomosynthesis unaided and reading breast tomosynthesis with AI support. Rad, radiologist; SE, standard error; CI, confidence interval. > 75% = in the last 3 years > 75% devoted to breast imaging
| AUC (SE) | Reading time in s (95% CI) | |||||||
|---|---|---|---|---|---|---|---|---|
| Rad. | With SM | > 75% | Unaided | With AI support | Difference | Unaided | With AI support | % difference |
| 1 | Y | N | 0.817 (0.031) | 0.837 (0.029) | + 0.020 (0.030) | 45 (43, 48) | 33 (31, 36) | −26 (−31, −21) |
| 2 | Y | N | 0.745 (0.031) | 0.792 (0.030) | + 0.047 (0.034) | 19 (17, 21) | 16 (14, 18) | −17 (−29, −4) |
| 3 | Y | Y | 0.813 (0.030) | 0.901 (0.023) | + 0.088 (0.030) | 29 (27, 31) | 27 (25, 29) | −6 (−14, 2) |
| 4 | Y | Y | 0.862 (0.027) | 0.872 (0.026) | + 0.010 (0.027) | 67 (64, 70) | 48 (46, 55) | −28 (−32, −25) |
| 5 | Y | N | 0.820 (0.032) | 0.868 (0.028) | + 0.047 (0.029) | 62 (59, 64) | 49 (46, 51) | −21 (−25, −17) |
| 6 | Y | Y | 0.886 (0.027) | 0.896 (0.025) | + 0.011 (0.018) | 46 (44, 49) | 38 (35, 40) | −19 (−24, −14) |
| 7 | Y | N | 0.799 (0.030) | 0.863 (0.027) | + 0.065 (0.031) | 45 (43, 47) | 26 (24, 28) | −42 (−48, −38) |
| 8 | Y | Y | 0.837 (0.029) | 0.884 (0.026) | + 0.047 (0.030) | 24 (22, 26) | 28 (26, 30) | 20 (10, 30) |
| 9 | Y | N | 0.801 (0.031) | 0.837 (0.027) | + 0.036 (0.031) | 27 (25, 29) | 27 (25, 29) | 2 (−7, 10) |
| 10 | N | Y | 0.878 (0.026) | 0.892 (0.024) | + 0.014 (0.027) | 67 (65, 70) | 71 (68, 74) | 6 (3, 9) |
| 11 | N | N | 0.849 (0.029) | 0.882 (0.026) | + 0.032 (0.026) | 55 (52, 57) | 57 (54, 59) | 4 (−1, 8) |
| 12 | N | N | 0.835 (0.029) | 0.829 (0.030) | -0.006 (0.025) | 41 (38, 43) | 37 (35, 40) | −7 (−13, −2) |
| 13 | N | Y | 0.859 (0.027) | 0.861 (0.027) | + 0.014 (0.029) | 40 (38, 43) | 32 (30, 34) | −22 (−27, −16) |
| 14 | N | Y | 0.873 (0.026) | 0.850 (0.028) | -0.023 (0.031) | 24 (21, 26) | 15 (13, 17) | −3 (−47, −27) |
| 15 | N | N | 0.849 (0.029) | 0.889 (0.026) | + 0.036 (0.028) | 64 (62, 67) | 61 (58, 63) | −6 (−9, −2) |
| 16 | N | N | 0.780 (0.031) | 0.835 (0.029) | + 0.054 (0.031) | 23 (21, 25) | 31 (29, 34) | 38 (28, 48) |
| 17 | N | N | 0.796 (0.029) | 0.849 (0.028) | + 0.053 (0.029) | 19 (17, 21) | 23 (21, 25) | 20 (7, 32) |
| 18 | N | Y | 0.898 (0.025) | 0.908 (0.023) | + 0.010 (0.025) | 54 (52, 57) | 47 (44, 49) | −15 (−19, −10) |
Fig. 3Average differences in reading time (%) across radiologists using synthetic mammograms and interactive navigation features between reading breast tomosynthesis exams unaided or reading with AI support, as a function of the exam-level score assigned by the AI system
Fig. 4Breast tomosynthesis exam (the synthetic image) of a woman without cancer and an exam-level cancer likelihood score of 1 (lowest) by the AI system. When reading the case aided, 17/18 (94%) radiologists read the exam faster, with an average reduction of reading time of −54% (from 36 to 19 s)
Fig. 5Breast tomosynthesis exam of a woman with an architectural distortion in the right breast, proven to be a 15-mm invasive ductal carcinoma (zoomed). The AI system marked the regions and assigned region-scores of 76 and 39 on cranio-caudal and mediolateral oblique views, respectively, and an exam-level cancer likelihood score of 10, the highest category. When reading the case unaided, 8/18 (44%) radiologists would have recalled the woman, a proportion that increased to 15/18 (83%) radiologists when reading the case with AI support
Fig. 6Stand-alone receiver operating characteristic curve of the AI support system, together with the operating points of the 18 individual radiologists reading breast tomosynthesis (DBT) unaided (left) or with AI support (right)