Age / Sex : 62 / F

Chief complaint :

Left hand mass (onset: 10 y)


What is your diagnosis?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).


Courtesy : 이슬기, Seul Ki Lee, 가톨릭대학교 성빈센트병원, Catholic University of Korea, St. Vincent’s Hospital

Ancient schwannoma

Discussion

Findings:

 About 1.4x2.0x2.4cm sized well-defined soft tissue mass in the dorsal aspect of 5th CMC joint level
- T1 iso to hyperintense SI and T2 heterogeneously high SI mass with heterogeneous enhancement
- multiple dark SI foci are noted within mass

- suspect of tail sign

Differential Diagnosis:

 tenosynovial giant cell tumor

malignant soft tissue tumor such as synovial sarcoma

Discussion:

 An ancient schwannoma is a subtype of schwannoma characterized by degeneration and a diffuse hypocellular area.

On MRI, heterogeneity may appear on T2-weighted images due to scattered myxoid, hemorrhagic, cystic, and necrotic areas.

 Calcification in schwannomas is extremely rare and can be found in ancient schwannomas. According to a few reports, these calcifications are usually scattered in distribution and punctate, mottled, or curvilinear in shape like our case

References:

1. Lee YS, Kim JO, Park SE. Ancient schwannoma of the thigh mimicking a malignant tumour: a report of two cases, with emphasis on MRI findings. Br J Radiol. 2010;83:e154-7.


2. Nakashima T, Tsurumaru D, Nishimuta Y, Miyasaka M, Nishie A, Honda H. A case of pelvic schwannoma presenting prominent eggshell-like calcification. Case Rep Radiol. 2013;2013:825078.


3. Isobe K, Shimizu T, Akahane T et-al. Imaging of ancient schwannoma. AJR Am J Roentgenol. 2004;183 (2): 331-6. doi:10.2214/ajr.183.2.1830331