Malignant Triton Tumor of the Distal Femur: Imaging Features of a Rare Entity

Reni Ibrahim*  -  Universitas Sebelas Maret; Dr. Moewardi General Hospital, Indonesia
Muchtar Hanafi  -  Universitas Sebelas Maret; Universitas Sebelas Maret Teaching Hospital, Indonesia
Amelia Tjandra Irawan  -  Universitas Sebelas Maret; Dr. Moewardi General Hospital, Indonesia

(*) Corresponding Author
DOI: 10.30659/sainsmed.v17i1.40815
Malignant Triton Tumor (MTT) is a subtype of Malignant Peripheral Nerve Sheath Tumor (MPNST), characterized by the appearance of striated muscle cells within the peripheral nerves. This rare tumor has an extremely low incidence rate of 0.001%. This study examines the radiological features of MPNST with the MTT subtype at the left distal femur. We present a case involving a 40-year-old woman who reported a lump in her left thigh, left calf, and abdominal area. This lump had rapidly become painful over the past two years. An MRI examination revealed typical manifestations associated with MPNST, with the lesion exceeding 5 cm (11.1 x 12.6 x 17.1 cm). Heterogeneous contrast enhancement appeared, and the lesion was compressing into and infiltrating adjacent tissue. Additionally, an MSCT revealed multiple solid lesions with peripheral contrast enhancement, which were compressing into and infiltrating adjacent tissue. Histopathological and immunohistochemical examinations confirmed the diagnosis of MTT. The patient subsequently underwent two wide tumor excisions, along with neoadjuvant radiotherapy and adjuvant chemotherapy. Following treatment, a chest X-ray examination revealed the presence of pulmonary metastases. The patient was discharged and will be reevaluated in three months. These findings suggest that MTT is highly aggressive and exhibits rapid growth, with lung metastases occurring within just one and a half years despite ongoing treatment.

Keywords: Malignant Triton Tumor; Malignant Peripheral Nerve Seath Tumor; Neurofibromatosis-1; Rhabdomyoblastic differentiation; Distal femur

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ISSN: 2339-093X (Online) | 2085-1545 (Print)
DOI : 10.30659/sainsmed

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