POSTER SECTIONS Coverpage Learning objectives Background Findings and procedure details Conclusion Personal information and conflict of interest References

ECR 2020 / C-13450

Metaplastic Breast Cancer: Imaging features and pathological correlation of a rare type of breast cancer

Congress:

ECR 2020

Poster Number:

C-13450

Type:

Educational Exhibit

Keywords:

Breast, Oncology, Mammography, MR, Ultrasound, Biopsy, Cancer, Not applicable

Authors:

V. S. D. M. Ogata, R. A. E. K. Matsumoto, N. de Barros, C. Shimizu, P. H. H. Souza; São Paulo/BR

DOI:

10.26044/ecr2020/C-13450

DOI-Link:

https://dx.doi.org/10.26044/ecr2020/C-13450

Fig. 1: Table 1: MBC imaging features and clinicopathologic findings.

Fig. 2: Table 2: MBC classification according to the World Health Organization (WHO).

Fig. 3: MBC encompasses tumors in which adenocarcinoma is found to co-exist with an...

Fig. 4: Case 1: MBC with squamous differentiation. Female, 54 yo.

Fig. 5: Case 1: MBC with squamous differentiation. Female, 54 yo.

Fig. 6: Case 1: MBC with squamous differentiation. Female, 54 yo.

Fig. 7: Case 1: MBC with squamous differentiation. Female, 54 yo.

Fig. 8: Case 2: MBC with squamous differentiation. Female, 40 yo.

Fig. 9: Case 2: MBC with squamous differentiation. Female, 40 yo.

Fig. 10: Case 2: MBC with squamous differentiation. Female, 40 yo.

Fig. 11: Case 3: MBC with squamous differentiation. Female, 36 yo.

Fig. 12: Case 3: MBC with squamous differentiation. Female, 36 yo.

Fig. 13: Case 4: MBC with chondroid metaplasia. Female, 77 yo.

Fig. 14: Case 4: MBC with chondroid metaplasia. Female, 77 yo.

Fig. 15: Case 5: MBC with osseous metaplasia. Female, 55 yo.

Fig. 16: Differential diagnosis of MBC includes IBC-NOS (especially triple-negative IBC...

Fig. 17: Differential diagnosis of MBC includes IBC-NOS (especially triple-negative IBC...

Fig. 18: Differential diagnosis of MBC includes IBC-NOS (especially triple-negative IBC...

Learning objectives

• To learn mammographic and sonographic features and magnetic resonance imaging (MRI) findings of metaplastic breast cancer (MBC) • To identify the differences and the similarities in the presentation between MBC and invasive breast cancer (IBC) not otherwise specified (NOS) • To learn the clinicopathologic findings of MBC

Background

• Breast cancer is classified into two major histological groups: IBC-NOS and special types of IBC • The main difference that distinguishes these groups is that IBC-NOS is a diagnosis of exclusion that comprises adenocarcinomas that fail to exhibit sufficient characteristics to warrant their classification in one of the special types • Special types of carcinoma account for up to 25% of all IBC and are associated with distinct biological features • One of these special types of IBC is MBC • MBC was officially...

Findings and procedure details

• Diagnosis is made by associating clinical, mammographic, sonographic, MRI and histopathological findings • Typical clinical findings of MBC includes a rapidly growing palpable breast mass • It can mimic a benign breast lesion (such as fibroadenoma) in the imaging methods conventionally used in the evaluation of the breast • Typical mammographic findings of MBC includes a round or irregular dense mass, with circumscribed or indistinct margins, rarely presenting calcifications • Typical sonographic findings of MBC includes an irregular microlobulated hypoechoic mass or complex cystic...

Conclusion

• Breast cancer is histologically classified in IBC-NOS or special type of IBC. MBC is one of these special types • MBC is characterized by differentiation of the neoplastic epithelium into squamous or mesenchymal phenotype • Diagnosis is made by associating clinical, imaging and histopathological findings • Most of the patients look for medical care after presenting a rapidly growing palpable mass • MBC can mimic a benign breast lesion in the imaging methods conventionally used in the evaluation of the breast • Compared to...

Personal information and conflict of interest

V. S. D. M. Ogata; São Paulo, SP/BR - nothing to disclose R. A. E. K. Matsumoto; Sao Paulo/BR - nothing to disclose C. Shimizu; São Paulo, SP/BR - nothing to disclose N. de Barros; Sao Paulo, SAO PAULO/BR - nothing to disclose P. H. H. Souza; São Paulo, SÃO PAULO/BR - nothing to disclose

References

• "Metaplastic breast cancer: histologic characteristics, prognostic factors and systemic treatment strategies" Schwartz et al. Experimental Hematology & Oncology (2013) 2:31 • "Metaplastic carcinoma of the breast: an immunohistochemical study", Altaf et al. Diagnostic Pathology (2014) 9:139 • "Metaplastic carcinoma of the breast: A case series and review of the literature", D.E. Boler et al. Journal of Oncological Sciences 2 (2016) 38-42 • "Clinicopathological features of metaplastic breast carcinoma", O. A. Hasdemir, et al. Adv Clin Exp Med. (2018) 27(4):509–513 • "Metaplastic Carcinoma of the...