Does the synthesised digital mammography (3D-DM) change the ACR density pattern?

Transcription

1 Does the synthesised digital mammography (3D-DM) change the ACR density pattern? Poster No.: B-0211 Congress: ECR 2015 Type: Scientific Paper Authors: P. MARTÍNEZ MIRAVETE, M. Millor Muruzábal, P. García Barquín, A. Elizalde, L. J. Pina Insausti, J. Etxano, P Bartolomé ; Zaragoza/ES, Pamplona/ES Keywords: Breast, Mammography, Diagnostic procedure, Cancer DOI: /ecr2015/B-0211 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 33

2 Purpose INTRODUCTION: Increased mammographic breast density is a moderate independent risk factor for breast cancer. The odds ratio for developing cancer for the most compared with the least dense breast tissue categories ranges from 1.8 to 6. Different classifications based on qualitative or quantitative criteria have been described. One of the most common used is ACR (BIRADS) classification based on density categories. [1] Digital mammography (2DM) remains the most commonly used procedure for mammographic screening. It performs bidimensional images while emitting the radiation dose in a predetermined direction from a static x-ray tube. Studies of tomosynthesis (3DM) obtain consecutive tridimensional images, while the xray tube moves performing an arc of variable amplitude while emitting regular pulses of low-dose radiation. Recently, a new concept has been introduced, the synthesized digital mammography (Synthesized-DM). It is based on obtaining conventional mammography image data from different slices of tomosynthesis. The main advantage of this new system is that it reduces the radiation dose, by approximately 40%-50%, because the conventional DM is not needed. [2,3] So, the purpose of our study was: - To evaluate the different ACR (BIRADS) density patterns observed in Conventional Digital Mammography (2D-DM) compared to Synthesized Digital Mammography (Synthesized-DM). Page 2 of 33

3 Methods and materials Patients selection From September 2013 to September 2014 we began to use the synthesized-dm and the COMBO mode (2D-DM + DBT). A total number of 8201 consecutive COMBO studies were performed at our institution in a clinical setting. Synthesized reconstruction images were obtained from all DBT studies. The informed consent was offered to all patients. All the studies were performed using a Selenia Dimensions unit (Hologic, USA). Study design We retrospectively selected an enriched sample with 136 patients (136 women, medium age of 48.4 years (21-88)). All patients underwent both techniques 2D-DM and synthesized-dm. The reading modes included standard craniocaudal (CC) and mediolateral-oblique (MLO) views of each breast. Two independent breast radiologists reviewed all the studies and classified them according to ACR density pattern (BIRADS edition 2013) [4] in both techniques as: ACR a: if the breast are almost entirely fatty. ACR b: if there are scattered areas of fibroglandular density. ACR c: if we can identify a heterogeneously dense breast tissue, which may obscure detection of small masses. And ACR d: if the breasts are extremely dense, which lowers the sensitivity of mammography. Statistical analysis Intraobserver and interobserver Kappa concordance indexes were calculated using SPSS 20.0 software. Page 3 of 33

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5 Results The distribution of the ACR density patterns for first reader was the following: In both studies the percentage of patients with ACR a was the same. In synthesized-dm there was a decrease of 4.7 % of patients with ACR b and 3.6 % of patients with ACR c. However, there was an increase of 8.3 % of patients with ACR d compared with 2D-DM. Fig. 2: Results of reader 1. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES The intra-observer kappa index for this first reader was so substantial or almost perfect agreement was found which was statistically significant (p<0.001). Page 5 of 33

6 Fig. 3: Intraobserver kappa index of reader 1. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES On the other hand, the distribution of ACR density patterns for the second reader was as follows: In both studies the percentage of patients with ACR a was also the same. In this case, in synthesized-dm we also identified a decrease of patients being 1.5 % in ACR b group and 4.4 % in ACR c group. And we also observed an increase, which in this case was of 5.8 %, of patients with ACR d compared with 2D-DM. Page 6 of 33

7 Fig. 4: Results of reader 2. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES The intra-observer kappa index for this second reader was so almost perfect agreement was found which was statistically significant (p<0.001). So both readers noted a trend to increase ACR d density patterns when using synthesized-dm. Page 7 of 33

8 Fig. 6: Summary of the results of both readers. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Interobserver concordance for 2D-DM was moderate (kappa index (p<0.01)) and slightly better (kappa index (p<0.01)) for synthesized-dm and both values were statistically significant (p<0.001). Page 8 of 33

9 Fig. 7: Intraobserver kappa indexes. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Cases Page 9 of 33

10 Fig. 8: This is a 49 year-old woman with intermediate density in their breasts. We can observe similar density pattern in both techniques. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 10 of 33

11 Fig. 9: This 45 year-old woman has heterogeneous breast density. Slightly higher breast density in the upper and posterior region can be identified, although it is similar in DM and in synthesized-dm. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 11 of 33

12 Fig. 10: In this case we can see a large breast density but similar appearance is observed in both techniques. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 12 of 33

13 Fig. 11: This 39 year-old woman has high breast density. However, similar appearence is observed in both techniques. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 13 of 33

14 Fig. 12: This is a 42 year-old woman with intermediate density in their breasts. In this case, we can see densities slight higher in synthesized-dm, especially in the retroareolar region. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 14 of 33

15 Fig. 13: This other woman also has intermediate breast density. Look how higher breast density can be identified diffusely in synthesized-dm. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 15 of 33

16 Fig. 14: This is a 45 year-old woman with heterogeneous breast density. Look at synthesized-dm, breast's density seems to be higher. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 16 of 33

17 Fig. 15: This is a particular woman with high breast density. Look at both techniques. In this case we can identify slight higher density in 2D-DM. References: Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 17 of 33

18 Images for this section: Fig. 2: Results of reader 1. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 18 of 33

19 Fig. 3: Intraobserver kappa index of reader 1. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 19 of 33

20 Fig. 4: Results of reader 2. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 20 of 33

21 Fig. 5: Intraobserver kappa index of reader 2. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 21 of 33

22 Fig. 6: Summary of the results of both readers. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 22 of 33

23 Fig. 7: Intraobserver kappa indexes. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 23 of 33

24 Fig. 8: This is a 49 year-old woman with intermediate density in their breasts. We can observe similar density pattern in both techniques. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 24 of 33

25 Fig. 9: This 45 year-old woman has heterogeneous breast density. Slightly higher breast density in the upper and posterior region can be identified, although it is similar in DM and in synthesized-dm. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 25 of 33

26 Fig. 10: In this case we can see a large breast density but similar appearance is observed in both techniques. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 26 of 33

27 Fig. 11: This 39 year-old woman has high breast density. However, similar appearence is observed in both techniques. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 27 of 33

28 Fig. 12: This is a 42 year-old woman with intermediate density in their breasts. In this case, we can see densities slight higher in synthesized-dm, especially in the retroareolar region. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 28 of 33

29 Fig. 13: This other woman also has intermediate breast density. Look how higher breast density can be identified diffusely in synthesized-dm. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 29 of 33

30 Fig. 14: This is a 45 year-old woman with heterogeneous breast density. Look at synthesized-dm, breast's density seems to be higher. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 30 of 33

31 Fig. 15: This is a particular woman with high breast density. Look at both techniques. In this case we can identify slight higher density in 2D-DM. Radiology, Clinica Universidad de Navarra - Pamplona/ES Page 31 of 33

32 Conclusion 1- Our results showed a trend to increase in ACR d density pattern when using synthesized-dm. 2- The intraobserver concordance was excellent for both readers. 3- The interobserver concordance was moderate for both techniques although slightly better for synthesized-dm. Page 32 of 33

33 References 1- Garrido-Estepa M, Ruiz-Perales F, Miranda J, Ascunce N, González-Román I, Sánchez-Contador C et all. Evaluation of mammographic density patterns: reproducibility and concordance among scales. BMC Cancer ;10: Martínez Miravete P, Etxano J. Tomosíntesis de mama: una nueva herramienta en el diagnóstico del cáncer de mama. Radiología j.rx Zuley ML, Guo B, Catullo VJ, Chough DM, Kelly AE, Lu AH et all. Comparison of twodimensional synthesized mammograms versus original digital mammograms alone and in combination with tomosynthesis images.radiology.2014;271: D'Orsi CJ, Sickles EA, Mendelson EB, Morris EA. ACR BI-RADS Atlas, Breast Imaging Reporting and Data System. Reston, VA: American College of Radiology Page 33 of 33