Lack of radiosensitivity predicts poor disease specific survival in myxoid liposarcoma

Abstract

Background Compared to other sarcomas, myxoid liposarcoma (ML) is known to be radiosensitive, with improved oncologic outcomes. Although these tumors “shrink” following radiotherapy, there is a paucity of data examining the degree of radiosensitivity and oncologic outcome. The purpose of the study was to evaluate pre‐ and postradiotherapy tumor volume to determine if size reduction impacts outcome. Methods We reviewed 62 patients with ML undergoing surgical resection combined with preoperative radiotherapy, with pre‐ and postradiotherapy MRI. This included 34 (55%) males, with a mean age of 47 ± 14 years. All tumors were deep to the fascia, and 12 (19%) patients had tumors with a >5% round‐cell component. Results The mean volume reduction was 54% ± 29%. Compared to patients with >25% volume reduction, patients with reduction ≤25% had worse 10‐year disease specific survival (86% vs. 37%, p < 0.01), in addition to an increased risk of metastatic disease (HR 4.63, p < 0.01) and death due to disease (HR 4.52, p < 0.01). Conclusion Lack of volume reduction is a risk factor for metastatic disease and subsequent death due to disease in patients with extremity ML treated with combined preoperative radiotherapy and surgery. This data could be used to stratify patients for adjuvant therapies and follow‐up intervals.

Emerging innovations and advancements in the treatment of extremity and truncal soft tissue sarcomas

“…75 Other investigators have shown the ability of preoperative RT to influence pathologic response markers, including hyalinization, necrosis, and fatty maturation. 76,77 Concurrently, studies delved into immunomodulatory impacts, including an increase in tumor-infiltrating lymphocytes post-RT and a more pronounced trend in the heightened expression of immune…”

“…A benefit of this was suggested in the DOREMY trial, which utilized tissue‐based changes in myxoid liposarcoma (MLS) to guide and analyze RT effects on MLS 75 . Other investigators have shown the ability of preoperative RT to influence pathologic response markers, including hyalinization, necrosis, and fatty maturation 76,77 . Concurrently, studies delved into immunomodulatory impacts, including an increase in tumor‐infiltrating lymphocytes post‐RT and a more pronounced trend in the heightened expression of immune suppressors 78 .…”

What’s New in Musculoskeletal Tumor Surgery

“…The authors found that most patients with extraskeletal myxoid chondrosarcoma had localized disease at diagnosis and that these patients had a 5-year overall survival rate of 70%. Houdek et al assessed the impact of radiation therapy on disease-specific survival in 143 patients with myxoid liposarcoma and found that the lack of response to radiation therapy was associated with poorer disease-specific survival 56 .…”

“…Houdek et al evaluated the treatment outcomes of patients with extraskeletal Ewing sarcoma and reported that patients who underwent multimodal therapy, including a surgical procedure, chemotherapy, and radiation, had improved overall survival and progression-free survival compared with those who underwent a surgical procedure alone 57 . The authors also reported that tumor size and the presence of metastasis at diagnosis were significant factors associated with worse outcomes.…”