Palbociclib treatment in pleural mesothelioma cells triggered senescence markers including increased SA-β-galactosidase activity and IL-6/IL-8 secretion, but cells resumed growth after drug withdrawal. Conventional senolytics like navitoclax, venetoclax, and dasatinib failed to eliminate these pseudo-senescent cells, contrasting with cisplatin which induced permanent senescence. This finding challenges the emerging therapeutic strategy of combining senescence-inducing drugs with senolytics to eliminate cancer cells. The reversible nature of palbociclib-induced senescence represents a significant limitation for mesothelioma treatment, where durable responses are critical given the cancer's aggressive progression and poor prognosis. The research reveals important mechanistic distinctions between drug-induced senescence states that could reshape clinical trial designs. While senolytic combination therapy shows promise in other cancer types and aging research, this work suggests that not all senescence-inducing treatments create vulnerable cellular states. For the broader longevity field, these results highlight the complexity of cellular senescence and the need for more nuanced approaches when targeting senescent cells for therapeutic benefit.