Home   Case of Week Home   Jobs  Conferences   Fellowships   Books

3 December 2014 - Case of the Week #335

All cases are archived on our website. To view them sorted by number, diagnosis or category, visit our Home Page and click on the Case of the Week button on the left hand side. To subscribe or unsubscribe to the Case of the Week or our other email lists, click here.

Thanks to Dr. David Cohen, Herzliya Medical Center (Israel), for contributing this case. To contribute a Case of the Week, follow the guidelines on our Case of the Week page.

Save the Date!

Saturday, February 21, 2015
The Townsend Hotel
Birmingham, Michigan (USA)

Current Concepts in
GYN Oncology and Pathology

Sponsored by Karmanos Cancer Institute, Henry Ford Health System,
Wayne State University School of Medicine and the Detroit Medical Center

Course Director:
Rouba Ali-Fehmi, M.D.


For more information, please call (313) 745-3594 or
email wsupathology@gmail.com



Website news:

(1) Are you shopping at Amazon.com? Be sure to click on any Amazon.com link from our Home Page, our Books pages, or here. It helps support our website, without costing you anything!

(2) Our Feature page for December is Grossing Equipment / Workstations, and highlights our advertisers EXAKT Technologies, Inc., Leica Biosystems, Milestone Medical, MOPEC and Photodyne Technologies. It also contains an original short article, "Pathology Grossing Tools of the Trade: Blades and Scalpels", by Jaleh Mansouri, M.D.

(3) Get ready for our new Home Page, to arrive by the end of the year. All of the old links will be there, but they will be rearranged to make them a little easier to access and to provide a cleaner look. At this time, ONLY the Home page is being changed. Underlying the new Home Page is a state of the art Content Management System ("computer infrastructure"), which will create more uniformity on the pages, and allow for a Topic Search in the future.

(4) We are seeking experts to serve on our Editorial Board to provide a secondary review of topics as they are updated. Editorial Board members are listed on the Reviewers page, on the relevant Chapter page, and on all topics that they review. For more information on joining our Editorial Board, please click here or email Dr. Pernick at NatPernick@hotmail.com.

(5) Visit our Updates page to learn what topics have been revised.

Case of the Week #335

Clinical History:
A 31 year old man had a vascular lesion on the right leg near the knee. Prior medical history was significant only for a nasal sinus biopsy showing severe acute and chronic inflammation.

The mass was excised. It was large and fusiform, 14 x 8 x 6 cm, and focally encapsulated, but in other areas tumor was present on the margin. On sectioning, the tumor peripherally was grey-tan-white, soft and "sarcomatous". Centrally, it had irregular calcified and ossified tissue.

Micro images:

What is your diagnosis?

Extraskeletal mesenchymal chondrosarcoma

Mesenchymal chondrosarcoma is a rare cartilaginous tumor with a primitive component composed of mesenchymal cells at the condensation stage. It typically affects teenagers or young adults, with no gender preference. Common sites are the diaphysis of the jaw, pelvis, femur, ribs or spine. However, it often involves extraosseous structures such as the orbit, paraspinal region, meninges or extremity soft tissue (see Soft tissue chapter).

The tumor has a biphasic pattern with a hyaline cartilage component and a small blue cell malignancy, either adjacent or with a gradual interface. The cartilage component is well differentiated and demonstrates areas of endochondral ossification. The small cell component has a "staghorn" pattern of vasculature. It is hypercellular with a high nuclear-to-cytoplasmic ratio. Both components are usually immunoreactive for Sox9 (Hum Pathol 2010;41:653, Hum Pathol 2003;34:263).

The differential diagnosis includes other small blue cell tumors, including Ewing/PNET, lymphoma and small cell osteosarcoma, all of which typically lack chondroid lobules.

The prognosis is unpredictable. Survival may be short or prolonged after metastases are identified (Arch Pathol Lab Med 2012;136:61).

Nat Pernick, M.D., President
and Shivani Thakore, Associate Medical Editor
PathologyOutlines.com, Inc.
30100 Telegraph Road, Suite 408
Bingham Farms, Michigan (USA) 48025
Telephone: 248/646-0325
Email: NatPernick@Hotmail.com
Alternate email: NatPernick@gmail.com