Page views in 2023: 3
Page views in 2024 to date: 15
3 December 2014 - Case #335

All cases are archived on our website. To view them sorted by case number, diagnosis or category, visit our main Case of the Month page. To subscribe or unsubscribe to Case of the Month or our other email lists, click here.

Thanks to Dr. David Cohen, Herzliya Medical Center (Israel), for contributing this case.


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.


Website
Hotel
Registration

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

[#4383]

Advertisement


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) 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.

Visit and follow our Blog to see recent updates to the website.



Case #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 gray-tan-white, soft and sarcomatous. Centrally, it had irregular calcified and ossified tissue.

Microscopic images:



What is your diagnosis?

Click here for diagnosis and discussion:


Diagnosis: Extraskeletal mesenchymal chondrosarcoma

Discussion:
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.

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 N:C 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).


Image 01 Image 02