Characteristic Mammography and Ultrasonography Findings of Ductal Carcinoma In Situ of the Breast Arising in Sclerosing Adenosis
Kumiko Tanaka
1, Hiroshi Sakuma
2, Goi Sakamoto
1, Futoshi Akiyama
1, and Fujio Kasumi
3135 Summary.
Some cases of ductal carcinoma in situ (DCIS) of the breast are arising in sclerosing adenosis. Sclerosing adenosis can sometimes resemble invasive carcinoma, especially in mammography (MMG). We attemped to reevaluate images from DCIS arising in sclerosing adenosis in MMG and ultrasonography (US) by comparing pathological reports. Four of the 90 (4.4%) cases of DCIS operated on at the Cancer Institute Hospital in 2001 arose from sclerosing adenosis. Three of the 4 cases showed characteristic images, focal distortion without mass lesion in MMG and indistinct and irregularly shaped hypoechoic area in US. It is usually easy to conclude the presence of malignancies from MMG findings. However, using US findings, it can difficult not only to detect abnormalities but also to determine the presence of malignancy. It is important to be able to detect this type of DCIS to make the correct diagnosis and to select suitable treatment.
Key words.
DCIS, Sclerosing adenosis, Distortion, Irregularly shaped hypoechoic lesion
Introduction
Some cases of ductal carcinoma in situ (DCIS) of the breast are arising in sclerosing adenosis. However, sclerosing adenosis can sometimes resemble invasive carcinoma.
Thus, DCIS arising in ducts affected by sclerosing adenosis can be misinterpreted as invasive carcinoma. In this study we attempted to reevaluate images from DCIS cases with sclerosing adenosis.
Patients and Methods
Ninety cases of DCIS were operated on at the Cancer Institute Hospital in 2001. Cases of DCIS arising in sclerosing adenosis were identified from pathological reports, and mammography (MMG) and ultrasonography (US) images were compared.
1Department of Breast Pathology, Cancer Institute Hospital, 1-37-1 Kamiikebukuro, Toshima- ku, Tokyo 170-8455, Japan
2Department of Ultrasonology, Cancer Institute Hospital, Tokyo, Japan
3Department of Breast Surgery, Cancer Institute Hospital, Tokyo, Japan
Results
Four of the 90 (4.4%) patients showed DCIS arising from sclerosing adenosis. We examined the MMG and US images from the patients and found that 3 of the 4 cases showed similar characteristics.
Case 1
A 56-year-old woman. The tumor was not palpable. Distortion in the MMG was prominent, and an irregularly shaped hypoechoic lesion was seen by US (Fig. 1).
Microscopic appearance showed carcinoma spreading into the sclerosing adenosis and distorted parenchyma, which reflected the distortion in the MMG (Fig. 2).
Case 2
A 59-year-old woman. Physical findings were a 40 ¥ 20 mm induration. Distortion in the MMG was associated with coarse calcification caused by an old fibroadenoma and was not related to the tumor. An irregularly shaped hypoechoic lesion was seen by US (Fig. 3). The microscopic appearance was similar to case 1 (Fig. 4).
Fig. 1. Focal distortion in mammography (MMG) (arrow); irregularly shaped hypoechoic area seen by ultrasonography
Case 3
A 60-year-old woman. A small round tumor (14 ¥ 14 mm) was palpable. A slight dis- tortion was observed by MMG and an irregular hypoechoic tumor was seen by US (Fig. 5). Microscopically, carcinoma was observed in the ducts of the sclerosing adeno- sis, but had spread to a relatively small area.
Fig. 2. Microscopic appear- ance of case 1. Ductal carci- noma in situ (DCIS) is spreading into sclerosing adenosis
Fig. 3. Focal distortion in MMG (arrow); irregularly shaped hypoechoic area by ultrasonography
Case 4
A 69-year-old woman. An oval, hard, 30 ¥ 23 mm tumor was palpable. This case is dif- ferent from the others, with a high-density mass detectable by MMG and an irregu- lar hypoechoic tumor by US (Fig. 6). Microscopically, intraductal carcinoma foci were gathering and in the process of forming a tumor.
Fig. 4. Microscopic appear- ance of case 2 was similar to that of case 1, i.e., DCIS spreading into sclerosing adenosis
Fig. 5. There was slight distortion in MMG (arrow) and an irregularly shaped, hypoechoic small tumor by ultrasonography
Discussion
1. Sclerosing adenosis causes architectural distortion by MMG, such that if DCIS arises in sclerosing adenosis, the MMG distortion is emphasized by the carcinoma foci. This kind of distortion observed by MMG can often be misinterpreted as inva- sive carcinoma.
2. Although sclerosing adenosis is difficult to detect by US, if DCIS does arise in scle- rosing adenosis, an indistinct and irregularly shaped hypoechoic lesion can often be observed. However, this kind of nonmass-forming image can be missed or overlooked.
Conclusion
It is important to be able to detect DCIS arising in sclerosing adenosis. However, this type of carcinoma tends not to show typical malignant features, especially by ultra- sound examination. Our findings showed that a characteristic distortion was observed by MMG, and an indistinct and an irregularly shaped hypoechoic lesion was observed by US in three of four cases of DCIS arising in sclerosing adenosis.
Fig. 6. High-density mass in MMG; oval tumor by ultrasonography. This case was different from the others
References
1. Rosen PP (2001) Rosen’s breast pathology. Lippincott/Williams & Wilkins, Philadelphia, pp 282–285
2. Page DL, Anderson TJ (1987) Diagnostic histopathology of the breast. Churchill Livingstone, Edinburgh, pp 89–103
3. Muto N, Akiyama F, Sakamoto G, et al (2000) Breast cancer arising in the duct of scle- rosing adenosis. Jpn J Breast Cancer 15(2):239–241
