Malignant triton tumour of the distal femur : imaging features of arare entity

Authors

  • Reni Ibrahim Department of Radiology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Central Java, Indonesia , Dr. Moewardi General Hospital, Surakarta, Central Java, Indonesia
  • Muchtar Hanafi Department of Radiology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Central Java, Indonesia , Universitas Sebelas Maret Teaching Hospital, Sukoharjo, Central Java, Indonesia
  • Amelia Tjandra Irawan Department of Radiology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Central Java, Indonesia , Dr. Moewardi General Hospital, Surakarta, Central Java, Indonesia
Published 2026-06-01
Issue Vol. 17 No. 1 (2026): June 2026
Section Case Report
DOI: https://doi.org/10.30659/sainsmed.v17i1.40815
Keywords: Malignant Triton Tumor, Malignant Peripheral, Nerve Sheath Tumour, Neurofibromatosis-1, Rhabdomyoblastic differentiation, Distal femur mass, Pulmonary metastasis of MPNST

Abstract

Malignant Triton tumour (MTT) is a rare rhabdomyoblastic variant of malignant peripheral nerve sheath
tumour (MPNST), characterised by striated muscle differentiation, with an incidence of approximately
0.001%. We report a 40-year-old woman with a rapidly painful, enlarging mass of the left distal femur
and associated palpable lesions in the left calf and abdomen. Multislice CT demonstrated multiple solid
lesions with peripheral contrast enhancement infiltrating adjacent tissues. MRI showed a large (>5 cm)
heterogeneous lesion measuring 9.4 × 8.4 × 9.2 cm with lobulated margins, heterogeneous contrast
enhancement, and mass effect on surrounding structures. Diagnosis and treatment: Histopathology
and immunohistochemistry confirmed the diagnosis of MTT. The patient underwent two wide tumour
excisions followed by adjuvant chemotherapy. Despite treatment, chest radiography one and a half
years later revealed pulmonary metastases. MTT is an aggressive tumour with rapid growth and a
high propensity for early metastasis. Radiologic features that should raise suspicion include large size,
lobulated margins, peripheral calcifications, and internal heterogeneity. Correlation of imaging with
clinical and histopathological findings is essential for timely diagnosis and treatment planning.

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© 2026 Author(s). Published by Sains Medika: Jurnal Kedokteran dan Kesehatan. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

How to Cite

Ibrahim, R., Hanafi, M., & Irawan, A. T. (2026). Malignant triton tumour of the distal femur : imaging features of arare entity. Sains Medika: Jurnal Kedokteran Dan Kesehatan, 17(1), 45-50. https://doi.org/10.30659/sainsmed.v17i1.40815

References

Alwan, M., Noar, G., Alwan, A., Alrwabdeh, S., & Etawi, M. (2024). Sporadic Malignant Triton Tumor of Shoulder: a Case Report. Medical Archives, 78(2), 174. https://doi.org/10.5455/medarh.2024.78.174-176

Asahi, Y., Nakagawa, T., Nakanishi, K., Takagi, T., Yoshikawa, H., Wakizaka, K., Yokoyama, R., Takahashi, M., & Sasaki, F. (2018). Malignant triton tumor of the duodenum: report of a case. International Cancer Conference Journal, 7(2), 52–58. https://doi.org/10.1007/s13691-018-0320-7

Aykut, B., Wieczorek, K., Schirmacher, P., Büchler, M. W., & Hoffmann, K. (2016). A rare case of recurrent malignant triton tumor in a male with NF1: Case report and mini-review. International Journal of Surgery Case Reports, 21, 121–124. https://doi.org/10.1016/j.ijscr.2016.03.003

Ban, Y., Oebisu, N., Yao, H., Takada, N., Hoshi, M., Nakamura, H., & Kohashi, K. (2024). Malignant Triton Tumor of the Distal Femur: A Case Report and Review of the Literature. In Vivo, 38(6), 3112–3116. https://doi.org/10.21873/invivo.13796

Bian, Y., Yongbo, X., Xi, Z., Zhao, D., Wu, H., & Liu, Y. (2019). A series of 10 malignant triton tumors in one institution. Medicine, 98(36), e16797. https://doi.org/10.1097/MD.0000000000016797

Chaudhry, I., Algazal, T., Cheema, A., Al Faraj, A., Al Malki, N., Mutairi, H., Abbas, A., & Amr, S. (2019). Mediastinal malignant triton tumor: A rare case series and review of literature. International Journal of Surgery Case Reports, 62, 115–119. https://doi.org/10.1016/j.ijscr.2019.08.020

Ghailane, S., Fauquier, S., Lepreux, S., & Le Huec, J.-C. (2019). Malignant triton tumor: Grand Round presentation of a rare aggressive case thoracolumbar spine tumor. European Spine Journal, 28(6), 1448–1452. https://doi.org/10.1007/s00586-017-5277-2

Hashimoto, K., Nishimura, S., & Goto, K. (2025). Advanced Metastatic Malignant Triton Tumor in Neurofibromatosis Type 1: A Case Report and Management Challenges. Cancer Diagnosis & Prognosis, 5(3), 410–416. https://doi.org/10.21873/cdp.10454

Hou, Z., Wang, C., Li, L., & Dong, L. (2020). Retroperitoneal malignant triton tumor in an infant: a case report and literature review. Translational Pediatrics, 9(4), 567–572. https://doi.org/10.21037/tp.2020.03.12

Jack, A. S., Witiw, C., Hockley, A., Huie, C. J., Wustrack, R., & Jacques, L. G. (2021). Malignant triton tumor in the setting of segmental neurofibromatosis: A rare case report and review of the literature. Interdisciplinary Neurosurgery, 24, 101073. https://doi.org/10.1016/j.inat.2020.101073

Jaing, T.-H., Chuang, C.-C., Jung, S.-M., Wu, C.-T., Tseng, C.-K., & Chen, C.-S. (2015). Malignant Triton Tumor of the Cervical Spine: Report of One Case and Review of the Literature. Pediatrics & Neonatology, 56(1), 58–61. https://doi.org/10.1016/j.pedneo.2013.01.013

James, A. W., Shurell, E., Singh, A., Dry, S. M., & Eilber, F. C. (2016). Malignant Peripheral Nerve Sheath Tumor. Surgical Oncology Clinics of North America, 25(4), 789–802. https://doi.org/10.1016/j.soc.2016.05.009

Kazawa, N. (2018). The US/ MRI/PET-CT Imaging Findings of a Malignant Triton Tumor of the Shoulder in a NF-1 (Von Recklinghausen Disease) Patient. Austin Journal of Medical Oncology, 5(2), 1041–1041. https://austinpublishinggroup.com/medical-oncology/fulltext/ajmo-v5-id1041.pdf

Li, Y., Peng, Q., Jiang, N., Molloy, D. P., Zeng, C., & Wu, Q. (2022). Computed tomography imaging features of malignant ‘triton’ tumor to facilitate its clinical diagnosis: report of two cases. BMC Medical Imaging, 22(1), 125. https://doi.org/10.1186/s12880-022-00848-9

Natalie Wu, L. M., & Lu, Q. R. (2019). Therapeutic Targets for Malignant Peripheral nerve Sheath Tumors. Future Neurology, 14(1). https://doi.org/10.2217/fnl-2018-0026

National Cancer Institute. (2020, July 22). Malignant Peripheral Nerve Sheath Tumor. https://www.cancer.gov/pediatric-adult-rare-tumor/rare-tumors/rare-soft-tissue-tumors/mpnst. Accessed 19 October 2024.

Tsagozis, P., Gaston, C. L., Haglund, F., Balko, J., Sumathi, V., Grimer, R., & Parry, M. (2020). The importance of surgical margins in malignant Triton tumour of the trunk and extremities. Oncology Letters, 21(2), 120. https://doi.org/10.3892/ol.2020.12381

Yao, C., Zhou, H., Dong, Y., Alhaskawi, A., Hasan Abdullah Ezzi, S., Wang, Z., Lai, J., Goutham Kota, V., Hasan Abdulla Hasan Abdulla, M., & Lu, H. (2023). Malignant Peripheral Nerve Sheath Tumors: Latest Concepts in Disease Pathogenesis and Clinical Management. Cancers, 15(4), 1077. https://doi.org/10.3390/cancers15041077

Zain, S., Mirchia, K., Hussien, A., & Mirchia, K. (2021). Malignant triton tumor of the anterior mediastinum: a rare tumor in a rare location. Radiology Case Reports, 16(7), 1770–1776. https://doi.org/10.1016/j.radcr.2021.04.019