Linear Breast Calcifications

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1 Residents Section Pattern of the Month Lai et al. Linear reast alcifications Residents Section Pattern of the Month Residents inradiology Kenny. Lai 1 Priscilla J. Slanetz Ronald L. Eisenberg Lai K, Slanetz PJ, Eisenberg RL Keywords: breast calcifications DOI: /JR Received pril 28, 2011; accepted without revision June 1, ll authors: Department of Radiology, eth Israel Deaconess Medical enter, Harvard Medical School, 330 rookline ve, oston, M ddress correspondence to R. L. Eisenberg (rleisenb@bidmc.harvard.edu). WE This is a Web exclusive article. JR 2012; 199:W151 W X/12/1992 W151 merican Roentgen Ray Society Linear reast alcifications reast calcifications are among the most common findings detected by radiologists on routine mammography. ecause they can reflect either a benign or malignant cause, calcifications often warrant further evaluation with spot compression magnification views in the craniocaudal and lateral projections. y analyzing the morphology, size, number, and distribution of breast calcifications, radiologists can divide them into three categories: benign, probably benign warranting follow-up, or suspicious warranting further evaluation with biopsy. reast calcifications can have a variety of morphologic patterns, such as linear branching, grouped, dystrophic, and dermal. This article focuses on the benign and malignant causes of linear calcifications (Table 1). enign auses of Linear alcifications Vascular alcification Vascular calcification is one of the most common findings encountered in mammography. Vascular calcification is not associated with malignancy and thus is among those entities that radiologists can confidently call benign on the basis of imaging alone. Initial studies suggested an association between breast vascular calcifications and diabetes, but later reports have shown this link to be weak. Other studies have suggested a relationship between visualized breast calcifications and an increased risk for coronary artery disease. However, vascular calcifications within the breast represent calcification within the medial layer of the vessel (Mönckeberg medial calcific sclerosis) as opposed to the intimal calcification seen in atherosclerotic disease elsewhere in the body. Other systemic processes reported to be associated with mammographic breast calcifications include chronic renal failure and hyperparathyroidism. Showing a distinctive tram-track (railroad track) configuration paralleling the vessel wall, vascular calcifications are often associated with a visible smooth tubular vessel (Fig. 1). Vascular calcifications have a serpentine course rather than the branching ductal pattern seen with other benign and malignant calcifications. However, vascular calcifications within smaller vessels and those deposited only on one side of a vessel wall can appear intraductal and present a diagnostic dilemma. Magnification views often are of value in distinguishing early vascular calcifications from other causes. Sutural alcification Sutural calcification typically occurs at or near the biopsy bed of an irradiated breast. In evaluating the treated breast, it is essential to carefully assess the surgical site. New calcifications in this region can reflect a broad spectrum of diagnostic considerations, including tumor recurrence, fat necrosis, dystrophic calcifications, and sutural calcifications. Like vascular calcifications within the breast, the typical appearance of sutural calcifications permits them to be easily dismissed as benign. However, at times, sutural calcifications potentially can be a source of TLE 1: Differential Diagnoses of Linear reast alcifications enign Vascular calcification Sutural calcification Secretory calcification Filariasis Malignant Ductal carcinoma in situ Invasive ductal carcinoma JR:199, ugust 2012 W151

2 Lai et al. Fig year-old woman with vascular calcification., Mediolateral oblique (), craniocaudal (), and magnification mediolateral () images of both breasts show linear serpentine tram-track calcifications typical of this benign process. confusion, especially early in their development when they might appear as an indeterminate grouping of calcifications without definitive benign features, suggesting possible recurrence. It has been suggested that sutural calcifications predominantly occur in areas of the breast subjected to prior radiation therapy. However, they rarely occur in the absence of radiation after extensive benign breast surgery. lthough the cause of sutural calcifications is incompletely understood, it has been suggested that impaired tissue healing and the foreign suture material serve as a matrix to create an environment conducive to calcium deposition. Sutural calcifications classically have a characteristic tubular curvilinear appearance with a knot seen associated with the surgical tie (Fig. 2). lthough they can appear anywhere in the breast, sutural calcifications occur at a site of prior surgery. The distribution of these calcifications in a straight line along a sutural plane can aid in making a diagnosis. However, sutural calcifications can assume various configurations. Depending on the percentage of suture material that has calcified, sutural calcifications can appear linear, curvilinear, or even as an indeterminate cluster. However, the key to diagnosis is the classic knotted configuration. s with the evaluation of all breast calcifications, magnification views often can identify this key trait if it is not clearly evident on standard mammographic views. Secretory alcifications lthough the cause is incompletely understood, secretory calcification appears to be related to duct ectasia. Secretory calcification is occasionally referred to as plasma cell mastitis because W152 JR:199, ugust 2012

3 Linear reast alcifications Fig. 2 Sutural calcifications in 77-year-old woman. and, raniocaudal () and mediolateral oblique () images of left breast obtained 4 years after lumpectomy and radiation therapy for invasive ductal carcinoma show curvilinear calcifications in lumpectomy site, with suggestion of knotted configuration, consistent with surgical ties. and D, Magnification craniocaudal () and mediolateral oblique (D) images better show classic knotted configuration of these calcifications, consistent with benign sutural calcifications. of the association of this condition with ductal infiltrates containing plasma cells. When the characteristic imaging appearance is evident, these calcifications can be dismissed as benign. Secretory calcifications are classically described as smooth thick (> 0.5 mm diameter) rodshaped calcifications (Fig. 3). However, there may be other patterns, such as more globular deposits with lucent centers. The various imaging findings likely depend on differences in the location of calcium deposition. It has been hypothesized that calcification of intraluminal de- D JR:199, ugust 2012 W153

4 Lai et al. Fig. 3 Secretory calcifications in 76-year-old woman., raniocaudal (), mediolateral (), and magnification mediolateral () images of left breast show characteristic diffuse smooth thick rodlike linear calcifications. bris within dilated ducts produces smooth thick rod-shaped calcifications. s expected given their intraductal origin, these calcifications often show a diffuse linear branching ductal distribution. Occasionally, these calcifications do not appear thickened and instead have a thinner needlelike appearance. Periductal (rather than intraductal) calcium deposition may appear as rod-shaped calcifications with central lucencies, which can also have a diffuse linear branching ductal distribution. reas of fat necrosis or ductal debris may present as more globular calcifications with lucent centers. lthough secretory calcifications can appear in isolation within a single duct, they often can be diffuse and bilateral. The smoothness and thickness of secretory calcifications is often enough to distinguish this benign entity from ductal carcinoma in situ. However, it is still essential for the radiologist to carefully examine all calcifications within a breast containing secretory calcifications to exclude any associated malignancy. Ductal carcinoma in situ typically has a more irregular appearance than secretory calcifications (Fig. 4). Moreover, the calcifications in ductal carcinoma in situ lack lucent centers, appear thinner (often < 1 mm), and show a finer more discontinuous pattern. W154 JR:199, ugust 2012

5 Linear reast alcifications Fig. 4 Ductal carcinoma in situ in 74-year-old woman recalled from screening mammography for further evaluation of calcifications., raniocaudal () and mediolateral oblique () images of right breast show linear rodlike calcifications consistent with secretory calcifications in upper outer right breast. However, there is additional group of indeterminate pleomorphic microcalcifications in lower outer right breast, which project in area of secretory calcifications on magnification craniocaudal image (). Subsequent biopsy under stereotactic guidance of this pleomorphic group of calcifications showed ductal carcinoma in situ. Filariasis Most commonly related to infection by Wuchereria bancrofti, filarial infection of the breast should be considered within the differential diagnosis for linear breast calcifications if the patient has had exposure to an endemic area (e.g., South and entral merica, the aribbean, frica, Southeast sia, hina, and northern ustralia). Filarial breast calcifications appear to represent chronic sequela of infection, presenting months to years after exposure. Therefore, it is important to consider this diagnosis not only among people living in or emigrating from endemic areas but also in those who have traveled to or visited these areas at any time. cutely, filarial infection of the breast can present with an erythematous painful lump and progress to lymphedema and fibrosis. However, elephantiasis-like symptoms are seen less frequently within the breast than in the extremities and genitalia. The breast calcifications related to filariasis often have a characteristic serpiginous, wormlike appearance (Fig. 5). The adult form of W. bancrofti resides in the lymphatics, with regional inflammation and necrosis after the death of the worm thought to result in filarial calcifications taking the form of the worm. These calcifications are typically present and mammographically stable for many years. If seen on a baseline mammogram, the character- JR:199, ugust 2012 W155

6 Lai et al. Fig. 5 Filariasis in 65-year-old woman who emigrated from Nigeria., raniocaudal (), mediolateral (), and magnification mediolateral () images of right breast show serpentine wormlike configuration of linear calcifications within anterior breast that was unchanged from multiple prior mammograms. istic morphology and appropriate clinical history are the most helpful factors in diagnosing filarial calcifications. Malignant auses of Linear alcifications Ductal carcinoma in situ and invasive ductal carcinoma can present as various patterns of calcifications within the breast. In addition to fine linear and linear branching appearances, the calcifications of ductal carcinoma can be grouped, pleomorphic, and dot-dash. If linear calcifications are not clearly benign, as in the previously described vascular and secretory calcifications, further evaluation is imperative to exclude malignancy. The fine linear and linear branching calcifications associated with ductal carcinoma in situ and invasive ductal carcinoma typically follow a ductal distribution. These calcifications represent calcified debris and secretions within the intraductal system, which form in the acini of the terminal ductal lobular unit. Suspicious calcifications associated with ductal carcinoma in situ and W156 JR:199, ugust 2012

7 Linear reast alcifications Fig. 6 Ductal carcinoma in situ with invasive ductal carcinoma in 57-year-old woman with family history of breast cancer. and, Magnification craniocaudal (), and magnification mediolateral () images of right breast show numerous fine linear-branching microcalcifications with segmental distribution within inferior central breast. Subsequent biopsy of calcifications under stereotactic guidance revealed ductal carcinoma in situ with invasive ductal carcinoma. invasive ductal carcinoma typically do not appear as regular as secretory calcifications, lack lucent centers, and have a more delicate appearance. In addition, they often show a finer more interrupted dot-dash pattern (Fig. 6). nother feature of linear calcifications that should raise suspicion for malignancy is a clustered distribution because ductal carcinoma in situ is commonly confined to a single duct segment. However, the disease may be more widespread and show a segmental distribution. onclusion Linear calcification is a commonly encountered mammographic pattern. The combination of magnified spot compression views and a keen eye should permit the radiologist to discriminate suspicious calcifications warranting biopsy from those that are clearly benign and require no further workup. Suggested Reading 1. rribas J, Prieto, Díaz, alleja M, Nava E. alcifications of the breast in Onchocerca infection. reast J 2005; 11: aum JK, omstock H, Joseph L. Intramammary arterial calcifications associated with diabetes. Radiology 1980; 136: Davis SP, Stomper P, Weidner N, Meyer JE. Suture calcification mimicking recurrence in the irradiated breast: a potential pitfall in mammographic evaluation. Radiology 1989; 172: Kim H, Greenberg JS, Javitt M. reast calcifications due to Mönckeberg medial calcific sclerosis. RadioGraphics 1999; 19: Kopans D. reast imaging, 3rd ed. Philadelphia, P: Lippincott Williams & Wilkins, Lang P, Luchsinger IS, Rawling EG. Filariasis of the breast. rch Pathol Lab Med 1987; 111: Sickles E, Galvin H. reast arterial calcification in association with diabetes mellitus: too weak a correlation to have clinical utility. Radiology 1985; 155: Stacey-lear, Mcarthy K, Hall D, et al. alcified suture material in the breast after radiation therapy. Radiology 1992; 183: JR:199, ugust 2012 W157