A case report described a fatal tumor lysis syndrome episode after a single 1-mg starter dose of tarlatamab in a patient with relapsed small cell lung cancer. The complication emerged six days after dosing and occurred despite an initial limited clinical course. The report, published in Respirology Case Reports, highlights the need for heightened monitoring around early dosing when cytokine-release and rapid tumor shrinkage risks overlap. While tumor lysis syndrome remains rare, the timing in relation to the initial “priming” dose may prompt revisitation of precaution and risk-stratification practices for similar bispecific approaches.