J Korean Soc Radiol 2015;73(5):287-291 http://dx.doi.org/10.3348/jksr.2015.73.5.287
INTRODUCTION
Malignant melanoma of the breast has various manifestations, usually as primary malignant melanoma of the breast skin, ma- lignant melanoma metastasis to the breast, or in-transit metasta- ses to breast tissue and breast skin (1). Primary malignant mela- noma involving breast parenchyma is extremely rare (1, 2).
Here, we present a case of a 45-year-old female who had pri- mary breast melanoma with mammography, ultrasonography, and magnetic resonance imaging findings.
CASE REPORT
A 45-year-old woman presented with a solitary, palpable mass in the left breast that she had noticed 2 months previously. There was not any remarkable personal or familial medical history. On physical examination, an approximately 4-cm sized, firm mass
was palpable in the medial portion of the left breast without skin or nipple changes.
Left medio-lateral oblique mammogram (Senograph DMR;
GE Healthcare, Milwaukee, WI, USA) showed an approximately 4-cm sized, round, ill-defined, high-density mass in the lower portion of the left breast and enlarged lymph nodes in the left axilla (Fig. 1A). There was no combined microcalcification with- in or around the mass. Ultrasonography (iU22 unit; Philips Medi- cal System, Bothell, WA, USA) revealed an approximate 3.7 × 3.5 cm, round, microlobulated, low echoic mass with internal cystic portions in the lower inner quadrant of the left breast (Fig. 1B).
Magnetic resonance imaging (Achieva, Philips Medical system, Bothell, WA, USA) showed a well-defined mass with heteroge- neous high signal intensity and a dark rim on a T2-weighted im- age (Fig. 1C) and irregular enhancement on the rim and septum after contrast injection (Fig. 1D).
This lesion was considered as Breast Imaging Reporting and
Primary Melanoma of the Breast: A Case Report with Imaging Findings
유방의 원발성 흑색종: 증례보고와 그 영상의학적 소견Yoo Kyung Yeom, MD
1, Joo Hee Cha, MD
1*, Hak Hee Kim, MD
1, Hee Jung Shin, MD
1, Eun Young Chae, MD
1, Woo Jung Choi, MD
1, In Hye Song, MD
21Department of Radiology and Research Institute of Radiology, 2Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
Primary breast melanoma is extremely rare, and as such, there are no established radiologic findings in the literature. This report describes a case of primary malig- nant melanoma with mammography, ultrasonography, and magnetic resonance im- aging findings. Our case study demonstrates a well-circumscribed heterogeneous rim-enhancing mass, with an internal cystic or necrotic portion seen using three modalities. Thus, although rare, this condition should be included in the differential diagnosis of a well-demarcated heterogeneous breast mass, and further pathologi- cal confirmation is needed.
Index terms Breast Melanoma Primary
Received April 10, 2015 Revised May 14, 2015 Accepted May 29, 2015
*Corresponding author: Joo Hee Cha, MD Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea.
Tel. 82-2-3010-5995 Fax. 82-2-476-0090 E-mail: [email protected]
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distri- bution, and reproduction in any medium, provided the original work is properly cited.
Data System category 5, and core needle biopsy and modified radical mastectomy were performed. Positron emission tomog- raphy-CT scan showed hypermetabolic uptake in the left breast mass, and no other abnormal hypermetabolic lesion (Fig. 1E).
On gross specimen examination, the tumor was a firm, lobu- lated, and multifocal necrotic mass (5 × 4 × 4 cm). The cut sur- face was yellowish white and granular, and the overlying skin was not involved (Fig. 1F). Microscopically, the low power field
Fig. 1. A 45-year-old woman with a palpable mass in the left breast that she noticed 2 months previously.
A. Left medio-lateral oblique showing an approximate 4-cm sized, round, ill-defined, high-density mass (black arrows) in the lower portion of the left breast, and enlarged lymph nodes (white arrow) in the axilla.
B. Ultrasonography showing a round, microlobulated, low echoic mass with internal cystic portions in the lower inner quadrant of the left breast.
C, D. Magnetic resonance imaging showing a well-defined mass with heterogeneous high signal intensity and a dark rim on T2-weighted image (arrows) (C), and irregular enhancement on the rim and septum after contrast injection (D).
E. PET-CT scan shows hypermetabolic uptake in the left breast mass, and no other abnormal hypermetabolic lesion.
F. On gross specimen examination, a firm, lobulated, and multifocal necrotic mass (5 × 4 × 4 cm) is revealed. The cut surface is yellowish white and granular, and the overlying skin is not involved.
PET-CT = positron emission tomography-CT A
D
B
E
C
F
view of hematoxylin and eosin staining revealed a hypercellular mass with multifocal internal necrosis and hemorrhage infiltrat- ing to the adjacent breast parenchyma. On the high power field view, the tumor showed a diffuse, solid growth pattern without ductal differentiation. Tumor cells were highly pleomorphic and had clear cytoplasm and atypical nuclei. Mitoses were frequently seen. Intracellular pigments or granules were not observed. On immunohistochemical staining, tumor cells were positive for the proteins S-100 and HMB45, but negative for cytokeratin, while
entrapped non-neoplastic ducts were negative for S-100 protein and positive for cytokeratin. The overall features supported the diagnosis of malignant melanoma (Fig. 2).
DISCUSSION
Malignant melanoma is probably the most important and common tumor that metastasizes to the breast, apart from pri- mary contralateral mammary tumors and lymphomas and me-
Fig. 2. Microscopic images of the breast mass.
A. In the low power view (× 40), hypercellular mass is infiltrating to the adjacent breast parenchyma (black arrows). Multifocal necrosis and hem- orrhage are present in the tumor (white arrows).
B. In the high power view (× 400), the tumor shows a diffuse, solid growth pattern without ductal differentiation. Tumor cells are highly pleo- morphic and have clear cytoplasm and atypical nuclei. Mitoses are frequently seen. Intracellular pigments or granules are not observed.
C, D. On immunohistochemical staining (× 400), tumor cells are positive for S-100 protein (C) and HMB45 (not shown), but negative for cytoker- atin (D), while the entrapped non-neoplastic ducts are negative for S-100 protein (C) and positive for cytokeratin (D). The overall features sup- port the diagnosis of malignant melanoma.
A
C
B
D
tastases from cutaneous malignant melanoma (3). Primary ma- lignant melanoma can present with cutaneous tissue or breast parenchyma involvement. To date, a few cases of primary malig- nant melanoma in the breast have been reported, with most of them being cutaneous melanoma or focusing on the pathologi- cal findings (2). To the best of our knowledge, there is no ultra- sound or mammographic description of primary malignant mel- anoma in the literature, with the exception of one case report (4).
There has been no report of its MRI findings. Elena CT reported the first sonographic and mamographic findings of primary breast melanoma that were indicative of a benign lesion show- ing a well-demarcated mass (4). In our case, on mammography, a relatively well-circumscribed mass without any microcalcifica- tion was shown. Differential diagnoses could include benign le- sions such as a fibroadenoma or well-circumscribed malignant tumors, such as colloid carcinoma, papillary carcinoma, and medullary carcinoma. On ultrasonography, a round, microlobu- lated, low echoic mass was shown. There was no significant in- creased vascularity on Doppler study, unlike the previously re- ported case. On MRI, a well-defined mass with heterogeneous high signal intensity and a dark rim was shown on a T2-weight- ed image (Fig. 1C). After contrast media administration, an ir- regular rim and septal enhancement were revealed. Commonly, a relatively well-circumscribed mass and suspected internal cys- tic or necrotic portions are seen with all three modalities.
Similar to metastatic melanoma in the breast, the radiological findings of primary malignant melanoma are not always distin- guishable from primary breast cancer, or even from benign breast lesions (5, 6). It is therefore necessary to perform confirmatory pathological diagnosis, including pathological morphology and immunohistochemistry: 1) pleomorphism of tumor cells and nuclear atypia; 2) scattered intracellular pigment granules (al- though there are 6–10% of malignant melanomas exhibiting lit- tle or no pigment, which are termed amelanotic melanoma); 3) immunohistochemistry results demonstrating the positive ex- pression of the proteins S-100, HMB-45, and melan-A; 4) the edge of the tumor tissue and normal breast tissue does not ex- hibit a transition (7). Regarding immunohistochemistry, the positive expression of S-100 is an exceptionally sensitive indica- tor of malignant melanoma, however, it is also expressed in 50%
of breast cancer cases. Therefore, it must be observed in combi-
nation with the positive expression of HMB-45 and melan-A for the diagnosis of primary melanoma of the breast. Among these two markers, HMB-45 is more commonly used as confirmative staining for malignant melanoma, whereas other indicators, such as CK, vimentin, and SMA demonstrate negative expression and indicate the presentation of other types of tumors. Furthermore, Ki-67 staining may be used to distinguish between benign and malignant tumors (8). Finally, it is very important that extrama- mmary malignant melanoma metastases or tumor invasion from neighboring sites should be excluded before a diagnosis of primary malignant breast melanoma is established.
In summary, even though the radiological findings are non- specific, primary malignant melanoma should be considered in the differential diagnosis of a well-circumscribed heterogeneous solid mass with necrosis in the breast parenchyma.
REFERENCES
1. Ravdel L, Robinson WA, Lewis K, Gonzalez R. Metastatic melanoma in the breast: a report of 27 cases. J Surg Oncol 2006;94:101-104
2. Bernardo MM, Mascarenhas MJ, Lopes DP. Primary malig- nant melanoma of the breast. Acta Med Port 1980;2:39-43 3. Toombs BD, Kalisher L. Metastatic disease to the breast:
clinical, pathologic, and radiographic features. AJR Am J Roentgenol 1977;129:673-676
4. Teodorescu EC. Sonography and mammography of primary malignant breast melanoma. Med Ultrason 2008;10:55-58 5. Loffeld A, Marsden JR. Management of melanoma metas-
tasis to the breast: case series and review of the literature.
Br J Dermatol 2005;152:1206-1210
6. Bassi F, Gatti G, Mauri E, Ballardini B, De Pas T, Luini A.
Breast metastases from cutaneous malignant melanoma.
Breast 2004;13:533-535
7. He Y, Mou J, Luo D, Gao B, Wen Y. Primary malignant mela- noma of the breast: a case report and review of the litera- ture. Oncol Lett 2014;8:238-240
8. Ohsie SJ, Sarantopoulos GP, Cochran AJ, Binder SW. Immu- nohistochemical characteristics of melanoma. J Cutan Pathol 2008;35:433-444
유방의 원발성 흑색종: 증례보고와 그 영상의학적 소견
염유경
1· 차주희
1* · 김학희
1· 신희정
1· 채은영
1· 최우정
1· 송인혜
2유방 실질에 발생한 원발성 흑색종은 극히 드문 것으로 알려져 있으며 현재까지 그 방사선학적 소견에 대해 확립된 연구는 미미한 실정이다. 본 저자들은 유방 실질에 발생한 원발성 흑색종 1예를 경험하였기에 그 유방조영술과 초음파 및 자기공 명영상 소견을 보고하고자 한다. 본 증례의 유방 종양은 비교적 경계가 좋고 내부로 낭성 혹은 괴사성 부분을 포함하여 비 균질한 양상이었으며 그 주변부와 내부의 격막을 따라 조영증강이 되는 소견을 보였다. 따라서 비교적 경계가 좋은 비균질 성 유방종양의 방사선학적 소견을 보이는 경우 매우 드물지만 원발성 흑색종 역시 감별진단에 포함할 수 있을 것으로 생각 되며 이에 대해서는 병리학적 확진이 필요할 것으로 생각되는 바이다.
울산대학교 의과대학 서울아산병원 1영상의학과, 2병리과
