Distinct mutation patterns were observed between primary and metastatic tumors; primary tumors were enriched for mutations in <i>TP53</i> and <i>CDKN2A</i>, while metastatic lesions harbored unique alterations in genes like <i>CBLB</i> and <i>BUB1B</i>, suggesting pathways involved in immune evasion and chromosomal instability may drive disease progression. The gene discussed is BUB1B; the disease is metastatic neoplasm.