Learning objectives
To remind a rare soft tissue tumor of the foot which can be a diagnostic challenge: isolated,
sporadic neurofibroma.
Background
Introduction: Neurofibromas are benign peripheral nerve sheath tumors composed of Schwann cells,
fibroblasts and collagen.
Unlike schwannomas they are not encapsulated and infiltrate between the nerve fascicles causing fusiform enlargement of the nerve.
They account for slightly more than %5 of all benign soft tissue tumors (1,2).
There are three types of neurofibroma: localized,
diffuse and plexiform.
Localized neurofibroma is the most common form,
representing %90 of all cases.
The vast majority of localized neurofibromas are solitary and not associated with neurofibromatosis type 1 (3,4)....
Imaging findings OR Procedure Details
Plain x rays of right foot taken in two directions revealed no abnormality (Figure 1).
MRI showed well-defined expansive soft tissue mass deeply seated between plantar muscles which was isointense with muscle on T1W images and hyperintense on T2W images (Figure 2).
No “target sign” was observed.
Contrast enhanced MRI sequences demonstrated heterogenous enhancement of the soft tissue mass (Figure 3).
Conclusion
Neurofibroma should be kept in mind in differential diagnosis of soft tissue masses in foot although it is a rare localization and there is no “target sign” appearance.
References
1) Kransdorf MJ.
Benign soft-tissue tumors in a large referral population: distribution of specific diagnosis by age,
sex,
and location.
AJR 1995;164:395-402.
2) Enzinger FM,
Weiss SW.
Benign tumors of peripheral nerves.
3rd ed.
In: Soft tissue tumors.
St Louis,
Mo: Mosby,
1995;821-888.
3) Kransdorf MJ.
Malignant soft-tissue tumors in large referral population: distribution of diagnosis by age,
sex,
and location.
AJR 1995;164:12-134.
4) Kransdorf M,
Murphey MD.
Neurogenic tumors.
In: Imaging of soft tissue tumors.
Philadelphia,
Pa: Saunders; 1997:235-273.
5) Pilavaki M,
Chourmouzi D,...
Personal Information
* Esin Gezmis,
M.D.,
Instructor of Radiology,
Baskent University Faculty of Medicine Zubeyde Hanim Practice and Research Center,
Department of Radiology
* Sedat Kıvanc Muratlı,
M.D.,
Baskent University Faculty of Medicine Zubeyde Hanim Practice and Research Center,
Department of Orthopedics and Traumatology
* Funda Ulu Ozturk,
M.D.,
Baskent University Faculty of Medicine Ankara Hospital,
Department of Radiology
* Cihan Altın,
M.D.,Assistant Professor,
Baskent University Faculty of Medicine Zubeyde Hanim Practice and Research Center,
Department of Cardiology