AIMS: Occasional cases of well-differentiated and dedifferentiated liposarcoma (LPS) contain myxoid stroma, leading to confusion with other sarcomas. The aim of this study was to analyse the clinicopathological and genetic features of well-differentiated/dedifferentiated LPS with prominent myxoid stroma. METHODS AND RESULTS: Fifty-six cases of LPS (22 well-differentiated; 34 dedifferentiated) with prominent myxoid stroma were evaluated. Most arose in the retroperitoneum, abdominal cavity, or spermatic cord. The mean size was 170 mm. Myxoid LPS-like plexiform vessels were conspicuous in 11 cases of well-differentiated LPS. In 22 cases of dedifferentiated LPS, myxofibrosarcoma-like curvilinear vessels were prominent. In other cases, the myxoid component had variably bland or pleomorphic morphology. By immunohistochemistry, staining for MDM2 was positive in 95% of cases, and CDK4 in 78%. Cytogenetics in 13 cases showed ring and giant marker chromosomes. Fluorescence in-situ hybridization showed amplification of 12q13-15 in six cases evaluated. Of 30 patients with follow-up, all but one had local recurrences (up to four), but only one has so far had distant metastases. CONCLUSIONS: Well-differentiated/dedifferentiated LPS with prominent myxoid stroma can closely resemble other sarcoma types, especially myxoid LPS and myxofibrosarcoma. The clinical presentation (large retroperitoneal or abdominal tumour) is a clue to the correct diagnosis; the degree of nuclear atypia helps to exclude myxoid LPS. Immunohistochemistry for MDM2 and CDK4 and genetic analysis can be useful to confirm the diagnosis.
AIMS: Occasional cases of well-differentiated and dedifferentiated liposarcoma (LPS) contain myxoid stroma, leading to confusion with other sarcomas. The aim of this study was to analyse the clinicopathological and genetic features of well-differentiated/dedifferentiated LPS with prominent myxoid stroma. METHODS AND RESULTS: Fifty-six cases of LPS (22 well-differentiated; 34 dedifferentiated) with prominent myxoid stroma were evaluated. Most arose in the retroperitoneum, abdominal cavity, or spermatic cord. The mean size was 170 mm. Myxoid LPS-like plexiform vessels were conspicuous in 11 cases of well-differentiated LPS. In 22 cases of dedifferentiated LPS, myxofibrosarcoma-like curvilinear vessels were prominent. In other cases, the myxoid component had variably bland or pleomorphic morphology. By immunohistochemistry, staining for MDM2 was positive in 95% of cases, and CDK4 in 78%. Cytogenetics in 13 cases showed ring and giant marker chromosomes. Fluorescence in-situ hybridization showed amplification of 12q13-15 in six cases evaluated. Of 30 patients with follow-up, all but one had local recurrences (up to four), but only one has so far had distant metastases. CONCLUSIONS: Well-differentiated/dedifferentiated LPS with prominent myxoid stroma can closely resemble other sarcoma types, especially myxoid LPS and myxofibrosarcoma. The clinical presentation (large retroperitoneal or abdominal tumour) is a clue to the correct diagnosis; the degree of nuclear atypia helps to exclude myxoid LPS. Immunohistochemistry for MDM2 and CDK4 and genetic analysis can be useful to confirm the diagnosis.
Authors: John S A Chrisinger; Tariq Al-Zaid; Emily Z Keung; Cheuk Leung; Heather Y Lin; Christina L Roland; Keila E Torres; Robert S Benjamin; Davis R Ingram; Samia Khan; Neeta Somaiah; Behrang Amini; Barry W Feig; Alexander J Lazar; Wei-Lien Wang Journal: J Surg Oncol Date: 2019-06-17 Impact factor: 3.454
Authors: Travis Peck; Kalla A Gervasio; Paul J L Zhang; Carol L Shields; Sara E Lally; Ralph C Eagle; Tatyana Milman Journal: Ocul Oncol Pathol Date: 2019-08-08
Authors: Naruhiko Ikoma; Keila E Torres; Neeta Somaiah; Kelly K Hunt; Janice N Cormier; William Tseng; Dina Lev; Raphael Pollock; Wei Lien Wang; Barry Feig Journal: Ann Surg Oncol Date: 2014-10-30 Impact factor: 5.344
Authors: Pablo Ortega; David Suster; Giovanni Falconieri; Eduardo Zambrano; Cesar A Moran; Carl Morrison; Saul Suster Journal: Mod Pathol Date: 2014-12-05 Impact factor: 7.842