bims-myxlip 2025-06-29 papers

Issue of 2025–06–29
three papers selected by
Laura Mannarino, Humanitas Research

Radiol Oncol. 2025 Jun 01. 59(2): 176-182

Radiographic and pathologic response of myxoid liposarcoma treated with preoperative radiotherapy.

Robert W Gao, Judith As Jebastin, Doris E Wenger, William S Harmsen, Andrew L Folpe, Michael G Haddock, Ivy A Petersen, Safia K Ahmed.

BACKGROUND: We retrospectively assessed volumetric response of myxoid liposarcoma (MLPS) with preoperative radiotherapy (RT) and sought to identify disease and treatment characteristics associated with response.
PATIENTS AND METHODS: We identified all patients with a histologic diagnosis of MLPS who received preoperative RT from 2013 to 2021 at our institution. We used cone beam computed tomography (CBCT) to assess changes in tumor volume and greatest dimension during treatment. Tumors were contoured on CBCT images prior to treatment and at the end of each week of RT. Percentage change in tumor volume and greatest dimension were calculated based on pre-treatment and final week contours. Patients with tumors incompletely visualized on CBCT were excluded from volume analysis but included on greatest dimension analysis. Magnetic resonance imaging (MRI) was used to evaluate pre- and post-RT radiographic features. Surgical pathology was reviewed to record pathologic characteristics.
RESULTS: Twenty patients met inclusion criteria. Most tumors (18/20) were low grade. The most frequent dose/fractionation scheme was 50 Gy in 25 fractions (16/20), with 3 patients receiving 36 Gy in 18 fractions. Median pre-RT volume and greatest dimension were 120 cc (interquartile range [IQR]: 56-399) and 11.2 cm (IQR: 8.4-14.1), respectively. Median percentage change in volume and greatest dimension were -37% (IQR: -57 to -29) and -10% (IQR: -20 to -7). All evaluable tumors decreased in volume during RT. Between pre- and post-RT MRI, most patients had a decrease in intratumoral (16/20) and peritumoral edema (11/20). Sixteen patients exhibited extensive pathologic response. There were no significant associations between radiographic and pathologic features and volumetric change. Local failure at 3 years was 9% (95% confidence interval: 1-59).
CONCLUSIONS: We report significant decreases in MLPS tumor size during preoperative RT. There may be a role for adaptive RT planning to reduce target volumes and minimize RT-associated morbidity.

Keywords: adaptive radiotherapy; myxoid liposarcoma; radiotherapy; sarcoma

DOI: https://doi.org/10.2478/raon-2025-0032

Magn Reson Med Sci. 2025 Jun 25.

Features of MR Imaging that Differentiate between Immunohistochemically Diagnosed Dedifferentiated Liposarcoma and Myxoid Liposarcoma.

Masaya Kawaguchi, Hiroki Kato, Kazuhiro Kobayashi, Tatsuhiko Miyazaki, Akihito Nagano, Yoshifumi Noda, Fuminori Hyodo, Masayuki Matsuo.

PURPOSE: This study aimed to compare the differences in the imaging findings for dedifferentiated liposarcoma (DDLS) and myxoid liposarcoma (MLS).
METHODS: The study included 30 patients with histopathologically confirmed DDLS and 13 patients with MLS. All DDLSs and MLSs were diagnosed immunohistochemically using MDM2 and DDIT3 staining, respectively. Conventional MRI, CT, and 18F-fluorodeoxyglucose-positron emission tomography/CT findings were retrospectively evaluated and compared between the 2 pathologies.
RESULTS: The median age of patients with DDLS was higher than that of patients with MLS (74 vs. 46 years, P < 0.01). In 10 DDLSs and 7 MLSs with fatty areas, the well-differentiated liposarcoma-like fatty areas were more common in DDLS than in MLS (70% vs. 14%), whereas septal/linear fatty areas were less common in DDLS than in MLS (30% vs. 86%, P < 0.05). The T2-hyperintense area of non-fatty area was less common in DDLS than in MLS (50% vs. 92%, P < 0.05), and the tumor-to-muscle signal intensity ratio of non-fatty areas on T2-weighted images was lower in DDLS than in MLS (3.18 vs. 5.92, P < 0.01). Apparent diffusion coefficient value was lower in DDLS than in MLS (1.29 vs. 2.10 × 10-3mm2/sec, P < 0.01). Unenhanced CT attenuation of non-fatty area was greater in DDLS than in MLS (33 vs. 19 Hounsfield unit, P < 0.01).
CONCLUSION: MRI features are valuable in differentiating MLS from DDLS. Younger age, septal/linear fatty areas, and high signal intensity of non-fatty areas on T2-weighted images were useful for diagnosing MLS.

Keywords: computed tomography; dedifferentiated; magnetic resonance imaging; myxoid; positron emission tomography–computed tomography

DOI: https://doi.org/10.2463/mrms.mp.2024-0186

Diseases. 2025 Jun 06. pii: 177. [Epub ahead of print]13(6):

Evaluation of Prognostic Factors in Myxoid Liposarcoma Treated with Combined Neoadjuvant Radiotherapy and Surgical Excision: Systematic Review.

Giuseppe Francesco Papalia, Giulia De Marco, Claudia Luciano, Luisana Sisca, Pasquale Farsetti, Bruno Vincenzi, Rocco Papalia.

PURPOSE: Myxoid liposarcoma (MLPS) is a malignant tumor that occurs predominantly in the deep soft tissues of the extremities. Preoperative radiotherapy (RT) is used to reduce tumor volume to achieve adequate surgical margins. This systematic review aims to evaluate the impact of preoperative RT on surgical margins, local recurrence (LR) rates, metastasis development, and overall survival in patients with MLPS and associated prognostic factors.
METHODS: A systematic literature search was conducted by two reviewers following PRISMA guidelines on PubMed, Scopus, and the Cochrane Library on 30 November 2024. We included prospective and retrospective cohort studies published in English that evaluate surgical margin status, LR and metastasis rates, and survival outcomes in patients undergoing surgical excision of MLPS following neoadjuvant radiotherapy. Two authors extracted tumor characteristics, percentage of round cells (RCs), change in tumor volume post-RT, surgical margins, postoperative complications, LR and metastasis rates, survival rates, and related prognostic factors.
RESULTS: The twelve studies included in this review involved 1483 patients with a mean age of 44.8 years. Tumors were mostly located in the lower limbs, deeply localized, and larger than 5 cm in most cases. The average LR and metastasis rates were 5.2% and 17%, respectively. The mean 5-year and 10-year overall survival rates were 87% and 74%, respectively. Poor prognosis was associated with >5% RC components, tumors larger than 15 cm, deep localization, and inadequate surgical margins.
CONCLUSION: The management of MLPS requires a multidisciplinary approach. Preoperative radiotherapy offers several advantages in reducing tumor volume and facilitating the achievement of adequate surgical margins, finally improving local control and long-term outcomes.

Keywords: myxoid liposarcoma; neoadjuvant radiotherapy; prognostic factors; surgical margins; systematic review

DOI: https://doi.org/10.3390/diseases13060177