Effect of liver toxicity on clinical outcome of patients with non‑small‑cell lung cancer treated with pemetrexed
- Authors:
- Published online on: November 4, 2014 https://doi.org/10.3892/mco.2014.452
- Pages: 334-340
Abstract
Introduction
Lung cancer is the leading cause of cancer-related mortality in numerous industrialized countries, with an incidence that is increasing worldwide (1). Platinum-based combination chemotherapy has been shown to improve the survival and quality of life of patients with advanced non-small-cell lung cancer (NSCLC), which accounts for ∼80% of all lung cancers; however, its prognosis remains poor.
Pemetrexed (PEM) is a novel pyrrolo[2,3-d]pyrimidine-based antifolate. It is transported into the cells via the reduced folate carrier. Upon cell entry, PEM is polyglutamylated to the activate pentaglutamate in a reaction catalyzed by folylpolyglutamate synthase. PEM inhibits multiple enzymes involved in pyrimidine and purine synthesis, including thymidylate synthase, dihydrofolate reductase and glycinamide ribonucleotide formyltransferase (2, 3). Available data suggest that PEM is exclusively more effective in non-squamous NSCLC compared to other non-platinum agents (4, 5).
Elevation of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels has been commonly reported in previous clinical studies of PEM (6–9). In a randomized study of two different doses of PEM, the incidence of ≥grade 2 AST and ALT elevation was 29.8 and 34.2%, respectively, in patients who received the standard dose (500 mg/m2) of PEM (8). Despite the high incidence of AST and ALT elevation, however, its effect on clinical outcome has not been investigated. If carcinoma cells exhibit characteristics similar to those of host cells, the therapeutic effect may be predictable from the reaction of hepatocytes to PEM.
In this study, we defined as liver toxicity (LT) any grade of AST or ALT elevation from baseline and investigated the association between LT and clinical outcome in patients with non-squamous NSCLC who were treated with a PEM-containing regimen.
Materials and methods
Patients
Between June, 2009 and June, 2012, 95 consecutive patients with advanced NSCLC were treated with PEM or PEM plus a platinum agent as first-line chemotherapy at the Department of Respiratory Medicine, Kyoto University Hospital. Patients who had received PEM-based chemotherapy as perioperative treatment were excluded from the analysis. Staging was performed according to the 7th edition of TNM classification (10). This study was approved by the institutional review board of Kyoto University and informed consent was obtained from all patients prior to enrollment in this study.
Evaluation of response and survival
Tumor response was assessed by the response evaluation criteria in solid tumors (RECIST, version 1.1) (11) every 2 cycles during chemotherapy and then based on clinical practice. Survival data were obtained through active follow-up based on the verification of the patients' vital status up to March 1, 2012. Progression-free survival (PFS) was defined as the time from the first administration of PEM to disease progression or death from any cause.
Evaluation and definition of LT
The following biochemical parameters were evaluated: AST, ALT, alkaline phosphatase (ALP), γ-glutamyl transpeptidase (γ-GTP), total bilirubin (TBil) and renal function (estimated creatinine clearance using the modified Cockcroft-Gault formula). Each toxicity was graded according to the National Cancer Institute Common Toxicity Criteria, version 4.0. The worst grade was identified and toxicities were recorded following deterioration by one or more grades compared to baseline. In this study, LT was defined as any grade of AST or ALT elevation from baseline.
Statistical analysis
Statistical comparisons were performed using the Student's t-test when data were normally distributed and non-parametric analysis using the Wilcoxon signed-rank test otherwise. The significance of the association between individual clinical factors was evaluated using the χ2 or Fisher's exact tests, as appropriate. A multivariate regression analysis was conducted using the Cox proportional hazards model. The survival rate was calculated by the Kaplan-Meier method and the statistical significance of the differences was evaluated using the log-rank test. P<0.05 was considered to indicate a statistically significant difference. All statistical analyses were performed using JMP 10.0.0 software (SAS Institute, Cary, NC, USA).
Results
Patient characteristics
A total of 95 patients with NSCLC were included in this analysis. The clinical characteristics of the patients are summarized in Table I. The patients comprised 51 men and 44 women, with a median age of 68 years. The performance status (PS) was generally good, with ∼92% of the patients exhibiting a PS of 0 or 1. In total, 55 patients (57.9%) were former or current smokers and 27 patients (28.4%) had a history of habitual alcohol consumption. There were few patients with positive hepatitis virus B (HBV) surface antigen, positive hepatitis virus C (HCV) antibody, or fatty liver. The majority of patients had adenocarcinoma histology and were diagnosed with stage IV disease. Liver metastasis was recorded in 10 patients.
Frequency and severity of LT
Compared with the high incidence of AST (63.2%) or ALT elevation (62.1%), the incidence of cholestatic enzyme elevation was relatively low (ALP, 16.8%; γ-GTP, 37.9%; and TBil, 6.3%). As shown in Fig. 1, 47 of the 67 patients who developed LT (70.1%) did so during the first cycle of chemotherapy. All cases of grade 1 LT improved spontaneously and there was no effect on subsequent PEM administration. By contrast, of the 16 patients with ≥ grade 2 LT, 10 patients required a treatment delay or a dose reduction from the subsequent cycle and PEM discontinuation was required in 1 patient (Table II).
![]() | Table II.Characteristics of 16 patients with grade 2 or higher AST or ALT elevation following chemotherapy with PEM . |
Risk factors for AST and ALT elevation
We investigated the association between LT and clinical factors, such as gender, age, body mass index (BMI), PS, disease stage, liver metastasis, alcohol consumption, hepatic comorbidity, treatment regimen, estimated creatinine clearance, dose intensity of PEM and baseline liver function, that may affect the pharmacokinetics of PEM (Table I). There was no significant difference between the LT and non-LT groups, with the exception of liver metastasis and the dose intensity of PEM: the incidence of liver metastasis and the dose intensity were higher in the non-LT group (P=0.0332 and 0.0478, respectively).
Efficacy
There were no recorded cases with complete response (CR), 35 with partial response (PR), 45 with stable disease (SD) and 15 with progressive disease (PD). The response rate (RR) and disease control rate (DCR) were 36.8 and 84.2%, respectively.
The association between clinical characteristics, including LT, and response to PEM, is shown in Table III. Younger age (<70 years), good PS (<2) and a doublet regimen were significant positive predictive factors for disease control (PR+SD) in the univariate analysis. The incidence of LT was significantly higher among non-PD patients compared to that in PD patients (P=0.0352). The RR and DCR were 43.3 and 89.6%, respectively, in patients with LT and 21.4 and 71.4%, respectively, in patients without LT (RR, P=0.0387; DCR, P=0.0352).
The median PFS of all patients was 5.6 months (95% CI: 4.2-6.5 months). Patients with LT achieved a significantly longer PFS compared to those without LT (6.3 vs. 2.9 months, P<0.0001; Fig. 2A). Similarly, the 16 patients with grade 2 or worse LT achieved a significantly longer PFS compared to their counterparts (6.3 and 4.0 months, respectively; P=0.0105; Fig. 2B). Furthermore, the median survival time and 1-year survival rate from the beginning of the treatment were 24.2 months and 79.6%, respectively, in patients with grade 2 or worse LT vs. 18.3 months and 74.3%, respectively, in their counterparts. There was no difference in overall survival (OS) (P=0.2426 vs. P=0.3109; Fig. 2C and D).
Subsequently, we conducted a Cox regression analysis to determine the correlation between PFS and clinical factors such as age (<70 vs. ≥70 years), gender (female vs. male), PS (0–1 vs. 2), epidermal growth factor receptor (EGFR) mutation status (mutant vs. wild-type/unknown), disease stage (III vs. IV), first-line therapy regimen (platinum plus PEM vs. PEM) and the presence of LT (present vs. absent). Among these factors, the presence of LT [hazard ratio (HR) = 0.389, 95% CI : 0.244-0.633 and P=0.0002] exerted a significant positive effect on PFS based on the univariate analysis. The multivariate analysis revealed that platinum plus PEM therapy (HR = 0.438, 95% CI : 0.210-0.823 and P=0.0119) and the presence of LT (HR = 0.341, 95% CI : 0.206-0.574 and P<0.0001) exerted a significant positive effect on PFS (Table IV).
![]() | Table IV.Cox proportional hazards model analysis of factors affecting progression-free survival (n=95). |
Discussion
The incidence of LT in this study was 70.5%. This is almost identical to that reported by previous clinical trials (6, 8, 9). Although approximately two-thirds of the patients who developed ≥ grade 2 LT required a treatment delay or a dose reduction from the subsequent cycle, PEM was successfully continued, except in 1 patient. These results suggest that LT is common among patients treated with PEM, although it is generally easily manageable. The most interesting result in this study was that patients who developed LT achieved a significantly higher RR and PFS compared to those without LT.
PEM is primarily eliminated in the urine, with 70–90% of the dose recovered as the unchanged parent drug within the first 24 h. It was hypothesized that PEM undergoes limited hepatic metabolism and the precise mechanism of PEM-induced liver injury has not been fully elucidated. The potential determinants of PEM activity include : the folate receptor carrier, which is the predominant route by which folates and several anti-folates gain entry into the cells; γ-glutamyl hydrolase, which removes glutamyl residues from polyglutamylated substrates, decreasing intracellular activity and retention of PEM; thymidylate synthase, which is the main target of this drug; and 5,10-methylenetetrahydrofolate reductase (MTHFR), which has a major impact on the regulation of the folic acid pathway (3, 12). These enzymes exist in liver cells as well as in tumor cells; therefore, PEM may also affect liver cells, leading to the development of LT.
The response of cancer cells to chemotherapy depends on a sufficient amount of active drug reaching the target and on whether that target is sensitive to the effects of the drug. These factors may also apply to normal cells, such as liver cells. The availability of the active drug to tumor or normal cells is affected by the pharmacokinetics of the drug, which may produce a similar effect in tumor and normal cells. However, no correlation between the levels of AST or ALT and PEM pharmacokinetic parameters has been reported thus far (13). In the present study, we were unable to verify a correlation between LT and the factors that affect the pharmacokinetics of PEM (such as, dose intensity and estimated creatinine clearance) (14).
The sensitivity of tumor and normal cells to chemotherapeutic agents may also be affected by genetic predisposition, which may similarly affect the two cell types. According to a previous randomized phase II study comparing PEM with PEM plus carboplatin (CBDCA), patients harbouring the C677T homozygous mutation of MTHFR, a key enzyme involved in folate metabolism, exhibited a prolonged PFS compared to patients with wild-type or heterozygous MTHFR mutations (15). This type of mutation has been shown to be associated with efficacy as well as toxicity in patients receiving methotrexate (16). In addition, Taniguchi et al (17) reported that the presence of MTHFR 677T was associated with an increased risk of ALT elevation in patients with rheumatoid arthritis treated with antirheumatic drugs. Those observations suggested that the polymorphism of genes that encode enzymes involved in folate metabolism, transportation and activation/inactivation may be associated with clinical outcome and LT in patients with advanced NSCLC receiving PEM-based therapy.
The present study had several limitations. Firstly, there was no definite rule for the evaluation of LT and the follow-up interval was based on clinical practice, due to its retrospective nature. Secondly, a false correlation between LT and patient outcome may have occured, since a higher incidence of LT was expected with the increasing number of chemotherapy cycles and patients surviving longer have a greater chance of receiving additional cycles of chemotherapy; however, these effects appear to be limited, as LT was mostly observed during the first 2 cycles in this analysis. To address this issue, we applied a novel strategy, restricting the primary analysis to patients who remained alive 30 days after the initiation of chemotherapy and the results did not change (data not shown).
To the best of our knowledge, this is the first study suggesting an association between LT and clinical outcome in NSCLC patients treated with PEM. Further studies are required to confirm this hypothesis.
References
Jemal A, Bray F, Center MM, Ferlay J, Ward E and Forman D: Global cancer statistics. CA Cancer J Clin. 61:69–90. 2011. View Article : Google Scholar : PubMed/NCBI | |
Schultz RM, Patel VF, Worzalla JF and Shih C: Role of thymidylate synthase in the antitumor activity of the multitargeted antifolate, LY231514. Anticancer Res. 19:437–443. 1999.PubMed/NCBI | |
Shih C, Chen VJ, Gossett LS, et al: LY231514, a pyrrolo[2,3-d]pyrimidine-based antifolate that inhibits multiple folate-requiring enzymes. Cancer Res. 57:1116–1123. 1997.PubMed/NCBI | |
Scagliotti G, Hanna N, Fossella F, et al: The differential efficacy of pemetrexed according to NSCLC histology: a review of two phase III studies. Oncologist. 14:253–263. 2009. View Article : Google Scholar : PubMed/NCBI | |
Scagliotti G, Brodowicz T, Shepherd FA, et al: Treatment-by-histology interaction analyses in three phase III trials show superiority of pemetrexed in nonsquamous non-small cell lung cancer. J Thorac Oncol. 6:64–70. 2011.PubMed/NCBI | |
Clarke SJ, Abratt R, Goedhals L, Boyer MJ, Millward MJ and Ackland SP: Phase II trial of pemetrexed disodium (ALIMTA, LY231514) in chemotherapy-naive patients with advanced non-small-cell lung cancer. Ann Oncol. 13:737–741. 2002. View Article : Google Scholar : PubMed/NCBI | |
Manegold C, Gatzemeier U, von Pawel J, Pirker R, Malayeri R, Blatter J and Krejcy K: Front-line treatment of advanced non-small-cell lung cancer with MTA (LY231514, pemetrexed disodium, ALIMTA) and cisplatin: a multicenter phase II trial. Ann Oncol. 11:435–440. 2000. View Article : Google Scholar : PubMed/NCBI | |
Ohe Y, Ichinose Y, Nakagawa K, et al: Efficacy and safety of two doses of pemetrexed supplemented with folic acid and vitamin B12 in previously treated patients with non-small cell lung cancer. Clin Cancer Res. 14:4206–4212. 2008. View Article : Google Scholar : PubMed/NCBI | |
Smit EF, Mattson K, von Pawel J, Manegold C, Clarke S and Postmus PE: ALIMTA (pemetrexed disodium) as second-line treatment of non-small-cell lung cancer: a phase II study. Ann Oncol. 14:455–460. 2003. View Article : Google Scholar : PubMed/NCBI | |
Goldstraw P, Crowley J, Chansky K, et al International Association for the Study of Lung Cancer International Staging Committee; Participating Institutions: The IASLC Lung Cancer Staging Project: proposals for the revision of the TNM stage groupings in the forthcoming (seventh) edition of the TNM Classification of malignant tumours. J Thorac Oncol. 2:706–714. 2007. View Article : Google Scholar : PubMed/NCBI | |
Eisenhauer EA, Therasse P, Bogaerts J, et al: New response evaluation criteria in solid tumours: revised RECIST guideline (version 1.1). Eur J Cancer. 45:228–247. 2009. View Article : Google Scholar : PubMed/NCBI | |
Schneider E and Ryan TJ: Gamma-glutamyl hydrolase and drug resistance. Clin Chim Acta. 374:25–32. 2006. View Article : Google Scholar : PubMed/NCBI | |
McDonald AC, Vasey PA, Adams L, et al: A phase I and pharmacokinetic study of LY231514, the multitargeted antifolate. Clin Cancer Res. 4:605–610. 1998.PubMed/NCBI | |
Mita AC, Sweeney CJ, Baker SD, et al: Phase I and pharmacokinetic study of pemetrexed administered every 3 weeks to advanced cancer patients with normal and impaired renal function. J Clin Oncol. 24:552–562. 2006. View Article : Google Scholar : PubMed/NCBI | |
Smit EF, Burgers SA, Biesma B, Smit HJ, Eppinga P, Dingemans AM, Joerger M, Schellens JH, Vincent A, van Zandwijk N and Groen HJ: Randomized phase II and pharmacogenetic study of pemetrexed compared with pemetrexed plus carboplatin in pretreated patients with advanced non-small-cell lung cancer. J Clin Oncol. 27:2038–2045. 2009. View Article : Google Scholar : PubMed/NCBI | |
Urano W, Taniguchi A, Yamanaka H, Tanaka E, Nakajima H, Matsuda Y, Akama H, Kitamura Y and Kamatani N: Polymorphisms in the methylenetetrahydrofolate reductase gene were associated with both the efficacy and the toxicity of methotrexate used for the treatment of rheumatoid arthritis, as evidenced by single locus and haplotype analyses. Pharmacogenetics. 12:183–190. 2002. View Article : Google Scholar : PubMed/NCBI | |
Taniguchi A, Urano W, Tanaka E, Furihata S, Kamitsuji S, Inoue E, Yamanaka M, Yamanaka H and Kamatani N: Validation of the associations between single nucleotide polymorphisms or haplotypes and responses to disease-modifying antirheumatic drugs in patients with rheumatoid arthritis: a proposal for prospective pharmacogenomic study in clinical practice. Pharmacogenet Genomics. 17:383–390. 2007. View Article : Google Scholar : PubMed/NCBI |