—  SPECIALTY CONFERENCE HANDOUT  — Breast Pathology Thursday, March 22, 2012, 7:30 PM Convention Centre 301-305 Clinical histories are printed below. Click on the case numbers for text and references of each case. Click on each slide thumbnail image for an enlarged view Mimics in Breast Pathology Moderator: LAURA C. COLLINS Beth Israel Deaconess MC Boston, MA Disclosure: In accordance with ACCME guidelines regarding disclosure, the USCAP policy requires that faculty members who have a significant financial or other relationship with a commercial company, entity, or service (which will be discussed in this Symposium) must disclose this to attendees. The Academy also requires that speakers disclose any products that are not labeled for the use under discussion. The speakers listed below have indicated they have nothing to disclose. Panelists: Melinda F. Lerwill, Mass General Hospital, Boston, MA Juan P. Palazzo, Jefferson University, Philadelphia, PA Kimberly H. Allison, Univ of WA Med Ctr, Seattle, WA Fouad Boulos, American Univ/Beirut, Beirut, Lebanon Jean F. Simpson, Vanderbilt Univ Med Ctr, Nashville, TN Clinical histories are displayed below. For the fastest viewing of virtual slides, click: under each thumbnail image below. You must have Aperio ImageScope installed on your PC. If you do not already have Aperio ImageScope, Windows users with administrator privileges may download and install a free version in order to view USCAP Virtual Slides. Click the icon on the right to get your free copy:   Or, click on slide thumbnail images to view each slide in a Web-based slide viewer, which is somewhat slower. If you have any difficulties viewing these slides, email or call George Clay at +1.724.449.1137. Case 1 - Click here for Text and References Submitted by: Melinda F. Lerwill - Mass General Hospital, Boston, MA Clinical Summary: 83-year-old woman with a 4.5 x 3 cm hard, palpable mass in the upper outer quadrant of the right breast. Case 1 - Slide 1 Click to view with ImageScope Click to view with a Web-Based Viewer Case 1 - Figure 1 The tumor cells demonstrate diffuse positivity for S-100. Case 1 - Figure 2 The tumor cells demonstrate diffuse positivity for HMB-45. Case 1 - Figure 3 The tumor cells demonstrate diffuse positivity for MART-1. Case 1 - Figure 4 The tumor cells demonstrate focal positivity for cytokeratin AE1/3-Cam5.2 Case 2 - Click here for Text and References Submitted by: Juan P. Palazzo - Jefferson University, Philadelphia, PA Clinical Summary: A seventy five year old female was diagnosed in a screening mammography with a focal asymmetry in the upper outer left breast. By ultrasound, there was an ovoid, hypoechoic mass with indistinct margins and no calcifications. Twenty years ago the patient had an invasive ductal carcinoma of the left breast and six years ago she had an invasive ductal carcinoma of the right breast. A wide local excision was performed. Case 2 - Figure 1 Case 2 - Figure 2 Case 2 - Figure 3 Case 2 - Figure 4 Case 2 - Figure 5 Case 2 - Figure 6 Case 2 - Figure 7 Case 3 - Click here for Text and References Submitted by: Kimberly H. Allison - Univ of WA Med Ctr, Seattle, WA Clinical History: 54 year old post-menopausal female now status post breast core needle biopsy for an area of calcifications found on annual mammogram. She is status post bilateral salpingo- oophorectomy at age 38 for benign cysts and has been on hormone replacement therapy for the last 16 years. She is G3P2 with her first pregnancy at age 23. She has no personal or family history of breast cancer but has a half sister with ovarian cancer. Case 3 - Slide 1 Click to view with ImageScope Click to view with a Web-Based Viewer Case 3 - Slide 2 Click to view with ImageScope Click to view with a Web-Based Viewer Case 3 - Figure 1 On low power, this breast needle core biopsy has several areas of potential interest. There is an intra- ductal proliferation present, microcysts, and an expanded lobule in the upper aspect of the image. Case 3 - Figure 2 The targeted calcifications are present in non-atypical ducts and lobules. Case 3 - Figure 3 The intraductal proliferation is characterized by a mixed population of cells with bland, overlapping nuclei. Slit-like spaces are being formed as well as micropapillary structures with small nuclei at their tips. These histologic changes are characteristic of usual ductal hyperplasia without atypia. A small calcification is evident in the epithelium focally as well. Case 3 - Figure 4 The expanded lobule seen on medium power is noted to contain areas with striking cytologic atypia. Some acini also contain a dense eosinophilic secretion reminiscent of thyroid colloid. Case 3 - Figure 5 On higher power the cytologic atypia in the lobule is more evident. The nuclei are very enlarged and contain prominent eosinophilic nucleoli. Many cells are multinucleate. The cytoplasm is also increased in volume and has a bubbly, vacuolated appearance, consistent with pseudolactational change. Case 3 - Figure 6 Blebs of cellular material containing both cytoplasm and nucleus are being shed into the center of the lobular acinus. These are findings associated with lactational and pseudolactational change. Case 3 - Figure 7 Some of the atypical acini contain both cytologic atypia as well as dense eosinophilic secretion where the pseudolactational change merges with cystic hypersecretory change. Several of the cells have spherules of eosinophilic material in their cytoplasm as well. Case 3 - Figure 8 On medium power other acini in the lobule are noted to have pseudolactational changes and cystic hypersecretory change but lack obvious cytologic atypia. Case 3 - Figure 9 More classic pseudolactational change without atypia and with hypersecretory secretion. Case 3 - Figure 10 The bubbly pseudolacataional change is evident in cytoplasm of the cells in these acini without the cytologic atypia present in the previous images. The hypersecretory secretion is present in these acini and is characteristically scalloped at the edges where it meets the surrounding epithelium. Case 4 - Click here for Text and References Submitted by: Fouad Boulos - American Univ/Beirut, Beirut, Lebanon Clinical Summary: 67-year-old patient with a 6 cm right breast mass. Case 4 - Figure 1 Phyllodes tumor with leaf-like architecture. Case 4 - Figure 2 Transition between phyllodes tumor and metaplastic carcinoma (Low power). Case 4 - Figure 3 Transition between phyllodes tumor and metaplastic carcinoma (Medium power). Case 4 - Figure 4 Metaplastic carcinoma with squamoid island Case 4 - Figure 5 Metaplastic carcinoma with diffuse growth and infiltration of fat. Case 4 - Figure 6 Intersecting curvilinear fascicles of metaplastic carcinoma. Case 4 - Figure 7 Metaplastic carcinoma with epithelioid tumor cells. Case 4 - Figure 8 High power of metaplastic carcinoma with atypical mitosis, mild atypia, tearing artifact, and few inflammatory cells. Case 4 - Figure 9 CK5/6 positivity in the metaplastic carcinoma Case 5 - Click here for Text and References Submitted by: Jean F. Simpson - Vanderbilt Univ Med Ctr, Nashville, TN Clinical Summary: A 56-year old woman had an excisional breast biopsy after a nodular density was detected on breast imaging. Case 5 - Figure 1 On low power, there is a nodular density with irregular placed epithelial nests and small glands. Case 5 - Figure 2 Closer view of irregular glands in an infiltrative patter, as well as an expanded space with marked epithelial proliferation Case 5 - Figure 3 Higher magnification view of the epithelial proliferation, including central secreted material Case 5 - Figure 4 Compressed epithelial clusters and glands are present at the periphery of a fibrotic center. Note fibrovascular core associated with epithelial proliferation at the bottom right of the image Case 5 - Figure 5 The epithelial cords and glandular structures are entrapped by the sclerotic center of the lesion Case 5 - Figure 6 The epithelial proliferation is associated with a predominantly fibrous core Case 5 - Figure 7 Entrapped glands maintain a parallel arrangement within the fibrous stroma Handouts for all Specialty Conferences will be accessible via the "Educational Materials" section on the homepage the morning after each respective conference. Printed copies of the handout will not be available at the meeting.