Recurrent leiomyosarcoma with de-differentiation to chondrosarcoma and osteosarcoma: a case report

Zara Summers, Aemelia Melloy, Eshwarshanker Jeyarajan, Timothy Wills, David Parker, Leigh Rutherford, Philip Townend


Leiomyosarcoma are a rare type of tumour of smooth muscle that can be found in the retroperitoneum. There is a paucity of reported data around dedifferentiation of leiomyosarcoma. Our case report describes de-differentiation of recurrent leiomyosarcoma into osteosarcoma and chondrosarcoma in a patient who had a local recurrence of his leiomyosarcoma. The recurrence is on a background of intermediate grade leiomyosarcoma of the retroperitoneum and he underwent his original resection in 2019 and included a right nephrectomy and right hemicolectomy. Our patient is currently undergoing radiotherapy and we will continue ongoing follow up for his progress.


Leiomyosarcoma, Retroperitoneum, Chondrosarcoma, Osteosarcoma

Full Text:



Choi JH, Ro JY. Retroperitoneal Sarcomas: An Update on the Diagnostic Pathology Approach. Diagnostics (Basel). 2020;10(9).

Mantas D, Garmpis N, Polychroni D, Garmpi A, Damaskos C, Liakea A, Sypsa G, Kouskos E. Retroperitoneal sarcomas: from diagnosis to treatment. Case series and review of the literature. G Chir. 2020;41(1):18-33.

WHO Classification of Tumours. Soft Tissue and Bone Tumours. 2020. Available at: Accessed on: 24 December 2020.

McBride SM, Raut CP, Lapidus M, Devlin PM, Marcus KJ, Bertagnolli M, et al. Locoregional recurrence after preoperative radiation therapy for retroperitoneal sarcoma: adverse impact of multifocal disease and potential implications of dose escalation. Ann Surg Oncol. 2013;20(7):2140-7.

Gronchi A, Palmerini E, Quagliuolo V, Martin Broto J, Lopez Pousa A, Grignani G, et al. Neoadjuvant Chemotherapy in High-Risk Soft Tissue Sarcomas: Final Results of a Randomized Trial From Italian (ISG), Spanish (GEIS), French (FSG), and Polish (PSG) Sarcoma Groups. J Clin Oncol. 2020;38(19):2178-86.

Caudle AS, Tepper JE, Calvo BF, Meyers MO, Goyal LK, Cance WG, Kim HJ. Complications associated with neoadjuvant radiotherapy in the multidisciplinary treatment of retroperitoneal sarcomas. Ann Surg Oncol. 2007;14(2):577-82.

Heslin MJ, Lewis JJ, Nadler E, Newman E, Woodruff JM, Casper ES, et al. Prognostic factors associated with long-term survival for retroperitoneal sarcoma: implications for management. J Clin Oncol. 1997;15(8):2832-9.

Bartlett EK, Roses RE, Meise C, Fraker DL, Kelz RR, Karakousis GC. Preoperative radiation for retroperitoneal sarcoma is not associated with increased early postoperative morbidity. J Surg Oncol. 2014;109(6):606-11.

Nicolas MM, Tamboli P, Gomez JA, Czerniak BA. Pleomorphic and dedifferentiated leiomyosarcoma: clinicopathologic and immunohistochemical study of 41 cases. Hum Pathol. 2010;41(5):663-71.

Oda Y, Miyajima K, Kawaguchi K, Tamiya S, Oshiro Y, Hachitanda Y, et al. Pleomorphic leiomyosarcoma: clinicopathologic and immunohistochemical study with special emphasis on its distinction from ordinary leiomyosarcoma and malignant fibrous histiocytoma. Am J Surg Pathol. 2001;25(8):1030-8.

Thway K, Jones RL, Noujaim J, Zaidi S, Miah AB, Fisher C. Dedifferentiated Liposarcoma: Updates on Morphology, Genetics, and Therapeutic Strategies. Adv Anat Pathol. 2016;23(1):30-40.

Evans HL, Soule EH, Winkelmann RK. Atypical lipoma, atypical intramuscular lipoma, and well differentiated retroperitoneal liposarcoma: a reappraisal of 30 cases formerly classified as well differentiated liposarcoma. Cancer. 1979;43(2):574-84.

Fukuda T, Ohnishi Y, Watanabe H, Kaneko H, Suzuki T. Dedifferentiated leiomyosarcoma of the intestinal tract: histological, ultrastructural and immunohistochemical examinations. Virchows Arch A Pathol Anat Histopathol. 1992;420(4):313-20.

Shimada S, Ishizawa T, Ishizawa K, Kamada K, Hirose T. Dedifferentiated liposarcoma with rhabdomyoblastic differentiation. Virchows Arch. 2005;447(5):835-41.

Binh MB, Guillou L, Hostein I, Ch√Ęteau MC, Collin F, Aurias A, et al. Dedifferentiated liposarcomas with divergent myosarcomatous differentiation developed in the internal trunk: a study of 27 cases and comparison to conventional dedifferentiated liposarcomas and leiomyosarcomas. Am J Surg Pathol. 2007;31(10):1557-66.

Chen E, O'Connell F, Fletcher CD. Dedifferentiated leiomyosarcoma: clinicopathological analysis of 18 cases. Histopathology. 2011;59(6):1135-43.

Cheng H, Miura JT, Lalehzari M, Rajeev R, Donahue AE, Bedi M, Gamblin TC, Turaga KK, Johnston FM. Neoadjuvant radiotherapy for retroperitoneal sarcoma: A systematic review. J Surg Oncol. 2016;113(6):628-34.

Cheng EY, Dusenbery KE, Winters MR, Thompson RC. Soft tissue sarcomas: preoperative versus postoperative radiotherapy. J Surg Oncol. 1996;61(2):90-9.