Predictive factors for long-term responders of pemetrexed maintenance treatment in non-small cell lung cancer.

Abstract

BACKGROUND:

We determined the clinical characteristics and predictive factors of long-term response to pemetrexed maintenance therapy as first-line treatment for non-small cell lung cancer (NSCLC).

METHODS:

A total of 950 advanced NSCLC patients received pemetrexed (500 mg/m2 ) plus cisplatin (60 mg/m2 ) (Pem-Cis) induction chemotherapy every three weeks as first-line treatment between January 2010 and August 2018. Patients who did not show progression after four cycles of Pem-Cis and received at least one cycle of pemetrexed maintenance were recruited (n = 199).

RESULTS:

Patients were divided into subgroups according to total cycles of pemetrexed: ≤ 10 (F10, n = 134) and > 10 (M10, n = 65). The M10 group had a higher proportion of patients with stage M1a (intrathoracic metastasis alone) and exhibited lower levels of thymidylate synthase (TS) than the F10 group (median H-score 10.0% vs. 60.0%; P = 0.031). Further subgrouping identified extreme responders: ≤ 7 (F7, n = 101) and ≥ 20 (M20, n = 26) cycles. The M20 group showed lower mean serum CEA levels before (17.5 vs. 147.0; P = 0.099) and after (6.9 vs. 53.2; P = 0.001) Pem-Cis treatment, and a higher incidence of normalization after Pem-Cis (abnormal 41.7% vs. 68.5%; P = 0.015). M1a stage, normalization of CEA levels after Pem-Cis, and lower TS H-score were predictors of progression-free survival in patients administered pemetrexed maintenance.

CONCLUSION:

M1a stage and lower TS expression were predictors of long-term response to pemetrexed maintenance. CEA normalization after Pem-Cis could be an additional surrogate marker of positive response to long-term treatment.

• Authors: Joon-Young Yoon, Cheol-Kyu Park, Yoo-Duk Choi, In-Jae Oh, Young-Chul Kim
• Journal: Thoracic cancer (Thorac Cancer) Vol. 10 Issue 4 Pg. 942-949 (04 2019) ISSN: 1759-7714 [Electronic] Singapore
• PMID: 30864258 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2019 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Chemical References

• Antineoplastic Agents
• Pemetrexed
• Thymidylate Synthase

Topics

• Aged
• Antineoplastic Agents (administration & dosage, therapeutic use)
• Carcinoma, Non-Small-Cell Lung (drug therapy, metabolism, pathology)
• Female
• Humans
• Lung Neoplasms (drug therapy, metabolism, pathology)
• Maintenance Chemotherapy
• Male
• Middle Aged
• Neoplasm Staging
• Pemetrexed (administration & dosage, therapeutic use)
• Retrospective Studies
• Survival Analysis
• Thymidylate Synthase (metabolism)
• Treatment Outcome