| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Invited Commentary |
Department of Radiology, George Washington University Medical Center, Washington, DC
Radial scars of the breast are benign but controversial. Recent research indicates that such lesions increase the risk of development of breast cancer almost twofold (1). In fact, these lesions may be a marker (similar to lobular carcinoma in situ) for increased risk of breast cancer in either breast (1). At both histopathologic examination and mammography, it is difficult to distinguish radial scar from carcinoma. In addition, some pathologists speculate that radial scar may be a precursor to breast carcinoma (2,3).
Alleva et al have done an excellent job in illustrating the close radiologic-pathologic correlation of radial scars. Their work highlights the difficulty in distinguishing these lesions from carcinoma at mammography as evidenced by the high prevalence of carcinoma in cases that demonstrate the typical mammographic appearance of radial scar. By illustrating the similarity between radial scar and carcinoma, they reinforce the imperative that all patients in whom the former is suspected at mammography must undergo biopsy. The authors also correctly emphasize that excisional rather than core biopsy should be specifically recommended by the radiologist in such cases. Stereotactic or ultrasound-guided core biopsy is contraindicated for these lesions for two important reasons: (a) The pathologist must analyze the overall architecture of the intact lesion to correctly diagnose radial scar, and (b) carcinoma as well as high-risk or marker lesions (eg, atypical ductal hyperplasia) may coexist with radial scar. Jackman et al (4) recently reported that carcinoma was found at excisional biopsy in two of five lesions with an initial finding of radial scar at core needle biopsy. Thus, core biopsy is not well suited to definitive diagnosis of suspected radial scar due to potential sampling error, which may lead to either false-positive or false-negative diagnosis.
The studies by Alleva et al and by Sloane and Mayers (3) reveal that carcinoma may be present within or adjacent to histologically proved radial scar. This situation probably occurs in 5%–20% of cases (3–5). Jackman et al (4) and Frouge et al (5) also report a high prevalence of carcinoma (45%–50% of cases) in mammographically suspected radial scar. Clearly, it is important that the radiologist recognize the typical mammographic appearance of radial scar and recommend excisional biopsy with preoperative needle localization. It is also important to clearly communicate to the surgeon and pathologist the mammography-based suspicion of radial scar.
Recent data from a study by Jacobs et al (1) indicate that radial scar represents an independent risk factor for subsequent development of breast cancer, with a relative risk of 1.8. Relative risk is further increased among women with radial scars greater than 4 mm in diameter (relative risk, 3.5) and when atypical hyperplasia is identified within a radial scar (relative risk, 3.5). These larger radial scars represent the subset most likely to be detected at mammography; however, we do not yet know whether they are more likely to contain coexistent atypical hyperplasia or carcinoma. It is also not known whether there is a pathogenic continuum among radial scar, atypical hyperplasia, and breast carcinoma. These questions require further investigation.
New data indicate that radial scar is a risk factor for development of breast cancer and that this risk is incrementally greater in patients with atypical hyperplasia or with radial scars greater than 4 mm in diameter. Therefore, it would be useful to know what percentage of mammographically suspected radial scars reviewed by Alleva et al were confirmed as such at histologic analysis and thus constituted true-positive findings. Of these true-positive results, what percentage were associated with atypical hyperplasia or carcinoma, and what was the mean size of the mammographically visible, true-positive lesions? Other studies have shown the prevalence of atypical hyperplasia within radial scar to be 8.1% (1) and 10.8% (3), respectively and the mean diameter of mammographically visible radial scars to be 1.3 cm (6). The comparative mammographic or histopathologic size of the radial scars reviewed by Alleva et al would be of interest because of the increased relative risk of carcinoma in larger radial scars that are more likely to be detected at mammography.
Alleva et al have succeeded in presenting a clear pictorial review of the classic mammographic features of radial scars as well as of identical appearing carcinomas. This review is particularly important because current evidence suggests that larger radial scars are likely to be of relatively greater clinical importance. Radiologists should be familiar with both the typical mammographic features of radial scar and the clinical implications of suspected radial scar so that these lesions may be handled appropriately by radiologists, surgeons, and pathologists. Patients should also be counseled as to the increased relative risk for breast cancer when radial scar is diagnosed. Whenever radial scar is encountered at core biopsy, it would be prudent to excise the lesion to assess for associated carcinoma or a high-risk lesion such as atypical hyperplasia.
References
Department of Radiology, Ochsner Clinic, New Orleans, Louisiana
We thank Dr Greenberg for her comments on our article. We agree that the size of radial scar is clinically important, particularly in light of the recent article by Jacobs et al (1). In our series, eight of the 22 lesions (36%) represented true-positive findings (ie, mammographically suspected radial scars that were confirmed at pathologic analysis). Of these eight histopathologically proved radial scars, one contained a focus of atypical ductal hyperplasia and another had an adjacent low-nuclear-grade cribriform and micropapillary ductal carcinoma in situ. We plan to reexamine our data to determine the size of these eight lesions at both mammography and histologic analysis. Furthermore, we hope to publish our findings in the near future, perhaps along with findings in additional cases that have been diagnosed at our institution since our earlier work.
References
Related Article
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOGRAPHICS | RADIOLOGY | RSNA JOURNALS ONLINE |
