Multicystic dedifferentiated retroperitoneal liposarcoma: tumour cyst fluid analysis and implications for management

Abstract

SUMMARYLiposarcomas are soft tissue sarcomas of adipocyte origin. We describe a case of a dedifferentiated retroperitoneal liposarcoma with an unusual presentation on recurrence as a large, multicystic tumour. The patient was a 72-year-old woman who had undergone multiple treatments including two prior resections. For her most recent locoregional disease recurrence, the patient was offered surgical debulking for symptom palliation. At this operation, performed after two cycles of chemotherapy, the tumour cyst fluid was analysed and found to have a predominance of immune cells with no identifiable malignant cells. This case and the results of our tumour cyst fluid analysis raise several interesting considerations for the management of this unique situation in a rare disease. BACKGROUND

Retroperitoneal dedifferentiated liposarcoma with huge cystic degeneration: A case report

“…Khoury et al analyzed the fluid in the cystic lesion of dedifferentiated liposarcoma and described that most of them (97.2%) were CD45-positive hematopoietic/immune cells. 4 Unfortunately, no cytological analysis was carried out, and histologically, the inner layer of the cyst wall contained a small number of atypical stromal cells in our case. Therefore, punctuation and analyses such as flow cytometry and cytology may be a little informative.…”

“…Careful histopathological examination of the cyst wall and an immunohistochemical study for MDM2 and CDK4 are necessary to make a correct diagnosis. Khoury et al analyzed the fluid in the cystic lesion of dedifferentiated liposarcoma and described that most of them (97.2%) were CD45‐positive hematopoietic/immune cells . Unfortunately, no cytological analysis was carried out, and histologically, the inner layer of the cyst wall contained a small number of atypical stromal cells in our case.…”

“…In this report, we describe the case of dedifferentiated liposarcoma with huge cystic change in the retroperitoneum of an elderly woman. Although a few cases of liposarcoma with degenerative multiple cystic degeneration as a minor component 3 or cystic change after chemoradiation therapy 4 have been reported, to the best of our knowledge, this is the first report of huge cystic dedifferentiated liposarcoma without a solid dedifferentiated component.…”

“…1,2 A small number of dedifferentiated liposarcoma cases may show cystic degeneration as a minor component, [3][4][5] potentially due to preoperative chemoradiation therapy. 4 However, huge cystic change with or without neoadjuvant therapy is a very rare phenomenon in WDL/DL cases. We describe, herein, a case of dedifferentiated liposarcoma with unusual huge cystic change with an involvement of the subserosa of the colon and the perirenal fat tissue.…”

Hypothesis: The Intratumoral Immune Response against a Cancer Progenitor Cell Impacts the Development of Well-Differentiated versus Dedifferentiated Disease in Liposarcoma

“…Alternatively, do the HCs recruit suppressive immune cell types or do they themselves directly suppress the mounting immune response? In support of the former, we recently described a case report of multicystic DD liposarcoma with a prominent monocytic immune cell subpopulation that is likely comprised of myeloid-derived suppressor cells and tumor-associated macrophages ( 43 ).…”