[PARAMOUNT trial: clinical meaning of continuous maintenance therapy in lung cancer]

Non-small cell lung cancer (NSCLC) remains one of the leading causes of cancer related deaths worldwide across both sex. Patients with Advanced -NSCLC (A-NSCLC) do not have curative treatment options, so the primary endpoint of every therapeutic decision aims to prolong survival, improving or maintain a good Quality of Life (QoL). Histology could represent a positive predictive factor for patients with Non squamous NSCLC (Nsq-NSCLC) respect to pemetrexed treatment. Pemetrexed is an antifolate that inhibits primarily thymidylate synthase (TS), together with dihydrofolate reductase and glycinamide ribonucleotide formyl transferase. Pemetrexed in combination with cisplatin is approved in the first line setting and as monotherapy in the switch or continuous maintenance of Non Squamous A-NSCLC. Maintenance therapy is a widely used therapeutic option in other solid and hematologic malignancies, but in the A-NSCLC represent an innovative approach. The rationale in this new setting of patients is based on the evidence that patients who benefit from an initial induction therapy platinum based may benefit from maintenance therapy with the third generation agent dropping the platinum drug after four to six cycles. We can define two types of maintenance therapy: continuation maintenance and switch maintenance. Major results in prolonging Overall Survival (OS) was reported with the continuation maintenance strategy as in the PARAMOUNT trial.