This clinical trial studies biomarker differences in samples from patients with undifferentiated sarcomas. Studying biomarker in tissue samples from patients with cancer in the laboratory may help doctors identify and learn more about biomarkers related to cancer

Study Subtype: Ancillary/Correlative Observational Study Model: Cohort Time Perspective: Prospective Biospecimen Retention: Samples With DNA Biospecimen Description: Tissue Study Population Description: Patients from ARST0332 study Sampling Method: Non-Probability Sample

PRIMARY OBJECTIVES:

I. To determine what proportion of unclassifiable sarcomas are unclassifiable because the initial evaluation was not sufficiently comprehensive versus what proportion can be regarded as "true" undifferentiated sarcoma when a comprehensive assessment has been performed.

II. To develop formal diagnostic criteria for establishing the diagnosis of undifferentiated sarcoma.

III. To determine whether undifferentiated sarcoma can be subdivided into separate and distinct pathologic entities that are distinguishable by light microscopy, immunohistochemistry, single nucleotide polymorphism (SNP) array profiling, or clinical features.

IV. To determine whether undifferentiated sarcomas with specific "actionable mutations" can be identified based on their histologic appearance, immunohistochemical staining characteristics, or SNP array profiling features.

OUTLINE:

Tissue samples are analyzed for loss of heterozygosity (LOH) and SNP array profiling using microarray and immunohistochemistry.

Inclusion Criteria:

• 49 cases of undifferentiated sarcomas from ARST0332 (additional cases may be ascertained as eligible for this current project that also fall under ARST0332 to be requested later if necessary)

Undifferentiated sarcomas from ARST0332