—  SPECIALTY CONFERENCE HANDOUT  — Dermatopathology Monday, February 28, 2011, 7:30 PM CC 001 A/B 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 Challenging Skin Tumors: Recognition and Recommendation Moderator: STEVEN R. TAHAN Beth Israel Deaconess Medical Center, 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: Rajiv M. Patel, University of Michigan Health System, Ann Arbor, MI Alireza Sepehr, Beth Israel Deaconess Medical Center, Boston, MA Thomas Brenn, Western General Hospital and The University of Edinburgh, Edinburgh S. David Hudnall, Yale University School of Medicine, New Haven, CT David E. Elder, Hospital of The University of Pennsylvania, Philadelphia, PA 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: Rajiv M. Patel - Clinical Summary: 29-year-old male with a 5-year history of a slow-growing nodule on the plantar aspect of the base of the first toe overlying the first metatarsal phalangeal joint. The lesion was excised by the patient's podiatrist. Case 1 - Slide 1 Click to view with ImageScope Click to view with a Web-Based Viewer Case 1 - Figure 1 Multinodular amelanotic poorly circumscribed tumor involving the dermis and infiltrating into deep soft tissue. Case 1 - Figure 2 Spindled to fusiform cells arrayed in nests and fascicles defined by fibrocollagenous septa. Case 1 - Figure 3 Focal myxoid change and microcystic growth pattern. Case 1 - Figure 4 Atypical multinucleated giant cells. Case 1 - Figure 5 Atypical multinucleated giant cells. Case 1 - Figure 6 Increased mitotic activity. Case 1 - Figure 7 Spindle cells are atypical and have vesicular nuclei, macronucleoli and variably clear to eosinophilic cytoplasm. Case 1 - Figure 8 Case 1 - Figure 9 Case 1 - Figure 10 Case 1 - Figure 11 Positive EWSR1 break-apart FISH. Split green and red signals (translocated EWSR1) with adjacent red/green signal (intact EWSR1). Case 2 - Click here for Text and References Submitted by: Alireza Sepehr - Clinical History: A 32-year-old man presented with a mass on his left index finger in 1993. A biopsy was performed. Pertinent Laboratory Data: In gross pathologic examination, the specimen consisted of gray to tan-pink nodular fragments of soft tissue and measured 3.0 x 1.0 x 0.5 cm in aggregate. The cut surface revealed a multilocular appearance with semi-viscous fluid contents. 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 2 - Figure 8 Case 2 - Figure 9 Case 2 - Figure 10 Case 2 - Figure 11 Case 2 - Figure 12 Case 2 - Figure 13 Case 2 - Figure 14 Case 2 - Figure 15 Case 2 - Figure 16 Case 2 - Figure 17 Case 2 - Figure 18 Case 2 - Figure 19 Case 2 - Figure 20 Case 2 - Figure 21 Case 3 - Click here for Text and References Submitted by: Thomas Brenn - Clinical Summary: A 79 year old female presents with three recently developed skin lesions in the right axilla (two biopsies are shown below). The patient has a past medical history of invasive breast carcinoma treated with mastectomy, axillary lymph node clearance and adjuvant radiation in 2004. Case 3 - Figure 1 This dermal based and relatively circumscribed tumor shows vasoformative elements with a complex and dissecting growth within pre-existing dermal collagen bundles. Vascular channels are lined by a single layer of endothelial cells lacking significant cytological atypia. Case 3 - Figure 2 This dermal based and relatively circumscribed tumor shows vasoformative elements with a complex and dissecting growth within pre-existing dermal collagen bundles. Vascular channels are lined by a single layer of endothelial cells lacking significant cytological atypia. Case 3 - Figure 3 This dermal based and relatively circumscribed tumor shows vasoformative elements with a complex and dissecting growth within pre-existing dermal collagen bundles. Vascular channels are lined by a single layer of endothelial cells lacking significant cytological atypia. Case 3 - Figure 4 Immunohistochemistry for CD31 stains lesional endothelial cells. It also emphasizes lesional circumscription and lack of subcutaneous involvement. Case 3 - Figure 5 Biopsy of a second lesion shows a circumscribed and nodular tumor with dilated vascular channels based within mid to deep dermis and abutting subcutaneous tissue. Case 3 - Figure 6 Higher magnification highlights the complex architecture. Also note the absence of endothelial cell layering and cytological atypia. Case 3 - Figure 7 Immunohistochemistry for CD31 demonstrates lesional circumscription as well as absence of endothelial cell multilayering. Case 3 - Figure 8 Immunohistochemistry for CD31 demonstrates lesional circumscription as well as absence of endothelial cell multilayering. Case 4 - Click here for Text and References Submitted by: S. David Hudnall - Clinical Summary: 9 year old afebrile boy presents with skin lesions of the upper extremities and face along with generalized lymphadenopathy. Pertinent Laboratory Data: CBC reveals pancytopenia. Biopsy of subcutaneous tissue from arm is obtained. Case 4 - Figure 1 Subcutaneous tissue from right arm. The monomorphic infiltrate consists of medium-sized blastic cells with round-oval nuclei and pale agranular cytoplasm. Based solely upon the morphology the differential diagnosis included lymphoblastic leukemia/lymphoma, acute monocytic leukemia, and extranodal NK/T cell lymphoma, nasal type. Case 4 - Figure 2 Bone marrow aspirate. The marrow contained a majority of large immature blastic cells with delicate folded nuclei and agranular vacuolated cytoplasm. On morphologic grounds alone this was considered to most likely represent acute monocytic leukemia. Case 5 - Click here for Text and References Submitted by: David E. Elder - Clinical Summary: A 9 year old child presented with a nodular lesion of the back. The lesion had appeared suddenly and grown rapidly over several weeks, more recently developing a crust and occasionally bleeding. A fragment of skin was received, with a central ulcerated nodule. Case 5 - Figure 1 Low-power view of a shave biopsy of a nodular tumor. Case 5 - Figure 2 The tumor abuts the adjacent epidermis without an associated junctional or in situ proliferation. Case 5 - Figure 3 Higher power view of the adjacent epidermis and the tumor. Case 5 - Figure 4 The tumor is ulcerated extensively across its surface. Case 5 - Figure 5 Tumor cells are arranged in nests, rather loosely placed in a vascular fibrous stroma. Case 5 - Figure 6 Frequent mitoses are present (e.g. in the green circle). Case 5 - Figure 7 The tumor cells at the base resemble those near the surface (failure of maturation) – compare with figures 4 and 5. Mitotic activity is also present near the base. Case 5 - Figure 8 The tumor is brightly and strongly positive with S100. Case 5 - Figure 9 There is focal reactivity with Melan-A. Case 5 - Figure 10 Low-power view of a bisected sentinel lymph node. Case 5 - Figure 11 Small sub capsular deposits of atypical cells are present in the lymph node parenchyma. The cells resemble those in the primary tumor. Case 5 - Figure 12 Melan-A stain of one of the deposits. Case 5 - Figure 13 S100 stain. 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.