Temozolomide treatment in refractory pituitary adenomas and pituitary carcinomas.

Background: Temozolomide (TMZ), a non-classical alkylating agent, possesses lipophilic properties that allow it to cross the blood-brain barrier, making it active within the central nervous system. Furthermore, the adverse reactions of the TMZ are relatively mild, which is why it is currently recommended as a first-line chemotherapy drug for refractory pituitary adenomas (RPAs) and pituitary carcinomas (PCs).

Summary: Systematic evaluations indicate a radiological response rate of 41% and a hormonal response rate of 53%, underscoring TMZ clinical efficacy, particularly when combined with radiotherapy. Functional tumors demonstrate a higher response rate compared to non-functional tumors. While the optimal duration of TMZ treatment remains undetermined, studies suggest that longer therapy durations may lead to better prognoses. Additionally, prior to TMZ administration, it is advisable to conduct immunohistochemical analysis of O6-methylguanine-DNA methyltransferase (MGMT), MSH2, MSH6, MLH1, PMS2, and N-methylpurine DNA glycosylase (MPG) to assess the potential impact of repair mechanisms such as direct repair (DR), mismatch repair pathway (MMR), and base excision repair (BER) on TMZ treatment. The efficacy of TMZ analogs, combined TMZ therapies, and TMZ with nanomaterials following TMZ treatment failure remains uncertain.

Key Messages: The involvement of experienced multidisciplinary pituitary teams in all management decisions for RPAs/PCs patients is essential.