Journal of the College of Physicians and Surgeons Pakistan
ISSN: 1022-386X (PRINT)
ISSN: 1681-7168 (ONLINE)
Affiliations
doi: 10.29271/jcpsp.2025.12.1611ABSTRACT
Objective: To determine factors influencing progression-free survival (PFS) in patients with advanced non-small cell lung cancer (NSCLC) treated with anlotinib and to create a predictive model using a nomogram.
Study Design: A descriptive study.
Place and Duration of the Study: Clinical Research Centre, Hefei Cancer Hospital, Chinese Academy of Sciences, Hebei, China, from July 2020 to 2024.
Methodology: Data of patients with advanced NSCLC receiving anlotinib treatment were retrieved from medical records. Potential predictors of PFS were first identified using univariate Cox proportional hazards regression analysis, and subsequently, multivariate Cox regression analysis was performed to identify key factors influencing PFS. A nomogram was constructed for PFS prediction.
Results: The study included 145 patients. Six factors were identified as significant predictors: combined use of proton pump inhibitors (PPI), nutritional risk score, monocyte percentage, pathological grading, combined use of immune checkpoint inhibitors (ICI), and body temperature. The combined use of PPI and Pathological Grading Ⅳ was found to be an independent risk factor for PFS, whereas the combined use of ICI, a nutritional risk score of 0, a monocyte percentage below 10.04%, and a body temperature under 36.2°C was identified as an independent protective factor. The areas under the ROC curve (AUC) at 1, 3, 6, and 12 months were 0.765 (95% CI: 0.672-0.859), 0.816 (95% CI: 0.759-0.873), 0.784 (95% CI: 0.718-0.849), and 0.773 (95% CI: 0.673-0.874), respectively. The model demonstrated a C-index of 0.71 (95% CI: 0.65-0.76), and the calibration curves indicated a high degree of alignment between the predicted and actual outcomes. A nomogram was successfully created to predict PFS.
Conclusion: Six significant factors affecting PFS in patients with advanced NSCLC treated with anlotinib were identified. A reliable nomogram was successfully constructed for the prediction of PFS, offering a tool to support personalised treatment planning.
Key Words: Anlotinib, Non-small cell lung cancer, Predictors, Cox regression, Nomogram.
INTRODUCTION
Globally, lung cancer accounts for the highest number of cancer-related fatalities, with 80-85% of these cases classified as non- small cell lung cancer (NSCLC).1 Most patients present with advan-ced disease, resulting in a poor prognosis.2 Targeted therapies and immunotherapies have improved overall survival (OS) and quality of life. Anlotinib, an orally administered multi-target tyrosine kinase inhibitor, works by suppressing tumour growth and preventing metastasis. In clinical comparisons with placebo, anlotinib has shown an increase of approximately 4 months in median progression-free survival (PFS) and 3 months in median OS.3
Several factors influence disease progression during anlotinib treatment, including genetic mutations, serological indicators, and combination therapies. Risk factors include obesity, high pre-treatment neutrophil-to-lymphocyte (NLR) ratio, elevated baseline AST, NSE, fibrinogen, ANC, squamous cell histology, non- epidermal growth factor receptor (EGFR) driver mutations, and platelet-to-lymphocyte (PLR) ratios.4,5 Hypertriglyceridaemia and combination therapy with immune checkpoint inhibitors (ICI) can extend PFS, while no correlation exists between EGFR mutations and efficacy.6-8 Elevated baseline total cholesterol (TC) and LDL levels are associated with increased risk of progression.9
The variability in patient responses to anlotinib, with disease control durations ranging from 1.5 to ≥18 months, highlights the need for predictive biomarkers.10 Nomograms, which synthesise multiple risk factors for prognostic estimates, have shown utility in lung cancer management. The researchers aimed to develop and validate a nomogram based on the clinical data retrieved from Hefei Cancer Hospital, Chinese Academy of Sciences, to optimise treatment outcome predictions for patients with NSCLC receiving anlotinib.
METHODOLOGY
A retrospective review was conducted on patients with meta-static or locally advanced NSCLC who received anlotinib monotherapy at the Clinical Research Centre, Hefei Cancer Hospital, Chinese Academy of Sciences, Hebei, China, from July 2020 to 2024. Patient selection was based on the following requirements: histologically verified Stage III/IV NSCLC, failure of two or more lines of standard therapy, completion of anlotinib treatment exceeding 14 days, and the availability of tumour response documentation through imaging studies (ultrasonography and computed tomography) according to RECIST guidelines. The institutional ethics board granted study approval. The research team collected comprehensive patient information, encompassing demographic details, histopathological findings, therapeutic history, baseline blood parameters, treatment-related toxicities, and clinical outcomes.
Data processing and statistical evaluation were performed using the R computing environment (4.2.0). The model construction consisted of two steps. Step 1 involved preliminary variable screening. Given the large number of variables derived from comprehensive patient information, initial screening was necessary to exclude clearly irrelevant variables. Univariate Cox regression analysis was employed with a statistical significance threshold of p <0.1.11 Variables meeting the criterion were included in step 2.
Step 2 involved multivariate Cox regression analysis. All variables meeting the screening criteria from step 1 were incorporated into the multivariate analysis. Forward selection and backward elimination methods were then applied to adjust for potential confounding factors and to identify the final set of variables, with statistical significance set at p <0.05. Continuous variables were dichotomised using optimal cut-offs from the cut-off R package.12,13
To validate the prognostic tool, bootstrap resampling (n = 1,000) was employed to generate calibration curves, and discriminative ability was calculated via C-statistics.14,15 The C-index and receiver operating characteristic (ROC) curve were used to evaluate the discriminative ability of the model. Higher values of C-index and the area under the ROC curve (AUC), approaching 1, indicated superior predictive performance, while calibration plots were generated to compare the observed and predicted probabilities. Statistical significance was drawn using a p-value threshold of 0.05.
RESULTS
A total of 145 patients with NSCLC were administered anlotinib during the study period. Their demographic profile and medical characteristics are presented in Table I.
The cohort of 145 anlotinib-treated patients showed a median PFS of 3.1 months (95% CI: 2.47-3.73). Univariate Cox regression analysis was conducted on 69 variables potentially affecting prognosis to evaluate their correlation with PFS. Table II presents the factors with p <0.1 identified in the univariate analysis results.
Table I: Patients’ demographic and medical characteristics.
|
Characteristics |
Patients (%) |
|
Combined use of PPI |
|
|
Yes |
68 (46.90) |
|
No |
77 (53.10) |
|
Combined use of ICI |
|
|
Yes |
95 (65.52) |
|
No |
50 (34.48) |
|
Age >65 |
65.16 (9.85) |
|
Yes |
80 (55.17) |
|
No |
65 (44.83) |
|
Gender |
|
|
Male |
104 (71.72) |
|
Female |
41 (28.28) |
|
Pathological |
|
|
Adenocarcinoma |
68 (46.90) |
|
Squamous cell carcinoma |
77 (53.10) |
|
Epidermal growth factor receptor mutant |
|
|
Yes |
25 (17.24) |
|
No |
120 (82.76) |
|
Mutations |
|
|
Pathological grading |
|
|
IV |
65 (44.83) |
|
III |
80 (55.17) |
|
Metastasis |
|
|
Yes |
104 (71.72) |
|
No |
41 (28.28) |
|
Brain metastases |
|
|
Yes |
20 (13.79) |
|
No |
125 (86.21) |
|
Radiation |
|
|
Yes |
124 (85.52) |
|
No |
24 (16.55) |
|
Number of previous treatment lines |
|
|
2 |
91 (62.76) |
|
>2 |
54 (37.24) |
|
Nutritional risk score = 0 |
|
|
Yes |
53 (36.55) |
|
No |
92 (63.45) |
|
Karnofsky performance status <70 |
|
|
Yes |
32 (22.07) |
|
No |
113 (77.93) |
|
Smoking |
|
|
Yes |
10 (06.90) |
|
No |
135 (93.10) |
|
Alcohol |
|
|
Yes |
8 (5.52) |
|
No |
137 (94.48) |
|
ICI: Immune checkpoint inhibitors; PPI: Proton pump inhibitors. |
|
Table II: Univariate Cox regression outcomes.
|
Characteristics |
HR (95% CI) |
p-values |
|
Nutritional risk score = 0 |
0.50 (0.30 ~ 0.81) |
0.005 |
|
Prealbumin |
0.99 (0.99 ~ 0.99) |
0.016 |
|
Body temperature |
1.74 (1.10 ~ 2.75) |
0.018 |
|
Monocyte percentage |
1.04 (1.01 ~ 1.07) |
0.05 |
|
Pathological grading Ⅳ |
1.46 (0.95 ~ 2.24) |
0.087 |
|
Monocyte count |
1.75 (0.91 ~ 3.37) |
0.096 |
|
Combined use of PPI |
2.42 (1.56 ~ 3.77) |
<.001 |
|
Combined use of ICI |
0.43 (0.28 ~ 0.67) |
<.001 |
|
HR: Hazard ratio; CI: Confidence interval; ICI: Immune checkpoint inhibitors; |
||
Table III: Results of multivariate Cox regression analysis.
|
Characteristics |
HR (95% CI) |
p-values |
|
Combined with PPI |
2.16 (1.36 ~ 3.43) |
0.001 |
|
Nutritional risk score = 0 |
0.53 (0.32 ~ 0.88) |
0.014 |
|
Monocyte percentage <10.04 |
0.56 (0.34 ~ 0.93) |
0.023 |
|
Pathological grading IV |
2.03 (1.29 ~ 3.19) |
0.002 |
|
Combined use of ICI |
0.55 (0.35 ~ 0.87) |
0.01 |
|
Body temperature <36.3℃ |
0.55 (0.33 ~ 0.92) |
0.022 |
|
HR: Hazard ratio, CI: Confidence interval; ICI: Immune checkpoint inhibitors; |
||
Table II presents potential prognostic factors for NSCLC patients treated with anlotinib, showing only those with p <0.1. The following optimal cut-off values for continuous variables were selected: prealbumin (160), body temperature (36.3°C), monocyte percentage (10.04%), and monocyte count (0.41).
Figure 1: ROC curves of the multivariate proportional hazards regression model at 1, 3, 6, and 12 months.
Table III shows the results of multivariate analysis. The combined use of PPI and pathological grading Ⅳ was identified as an independent risk factor, while the combined use of ICI, nutritional risk score = 0, monocyte percentage <10.04%, and body temperature <36.2°C was found to be an independent protective factor.
As shown in Figure 1, the AUC at 1, 3, 6, and 12 months were 0.765 (95% CI: 0.672-0.859), 0.816 (95% CI: 0.759-0.873), 0.784 (95% CI: 0.718-0.849), and 0.773 (95% CI: 0.673-0.874), respectively. The model demonstrated a C-index of 0.71 (95% CI: 0.65-0.76). The calibration curves (Figure 2) indicated a high degree of alignment between the predicted and actual outcomes. Based on the multivariate Cox model, a nomogram was created to predict PFS at different time points in NSCLC patients treated with anlotinib.
Figure 3 provides a prognostic tool for predicting PFS in NSCLC patients treated with anlotinib. To use the nomogram, the patient's value for each variable was located on its corresponding axis, and a vertical line was drawn upward to the point axis to determine the score assigned to each variable. These scores were then summed, and the total was located on the total points axis. A vertical line was drawn downward from this point to the survival axes to determine the probability of PFS at 1, 3, 6, and 12 months.
Figure 2: Calibration curves of the multivariate proportional hazards regression model at 1, 3, 6, and 12 months.
Figure 3: Nomogram for predicting PFS.
DISCUSSION
In this study, a nomogram was developed to predict PFS in NSCLC patients treated with anlotinib. Previous studies have suggested that the use of PPIs combined with tyrosine kinase inhibitors (TKIs) may negatively impact patient survival.16 The solubility of anlotinib is pH-dependent, and at pH 6.5, its solubility falls below the required level.17,18 Reduced absorptions of anlotinib when co-administered with PPIs may contribute to the shortened PFS observed in these patients.
This study identified the combination of anlotinib and ICI as a protective factor for prolonged PFS (HR: 0.54; 95% CI: 0.34-0.86), consistent with previous studies. For instance, Yu et al. reported improved PFS with an anlotinib-immuno-therapy combination versus anlotinib monotherapy (HR: 0.68; 95% CI: 0.68-0.97).19
Univariate Cox analysis showed a 1.74-fold increase in risk for each 1°C rise in body temperature. Otsuka et al. suggested that elevated body temperature promotes cancer cell growth and extracellular vesicle secretion, linking it to poor prognosis in breast cancer.20 Thus, increased body temperature may contribute to disease progression.
This study identified a nutritional risk score of 0 as a protective factor for PFS. Similarly, in a prognostic investigation, Chen et al. discovered that NSCLC patients exhibiting reduced nutritional status (PNI ≤42.48) experienced markedly abbreviated PFS relative to those with optimal nutritional indices (1.5 vs. 4.0 months; p = 0.010),21 indicating that nutritional status influences PFS in NSCLC patients treated with anlotinib.
Prior studies indicated that elevated NLR (>7.75), LDH (>254.65 U/L), AST, NSE, and fibrinogen levels were predictive of poor survival outcomes.22 In this study, univariate analysis failed to demonstrate such correlations. The calculated hazard ratios with 95% confidence intervals (0.96-1.04, 0.99-1.01, and 0.99-1.02, respectively) showed no statistical significance for these parameters. Prealbumin (HR 0.99, 95% CI 0.98-0.99) and monocyte count (HR 1.04, 95% CI 1.01-1.07) showed mild statistical significance.
Prealbumin reflects the protein levels and nutritional status of the body, aligning with studies linking higher albumin levels to improved survival in cancer patients.23 Monocyte count, part of the pan-immune inflammatory index, may predict survival and immune-related adverse events in late- stage NSCLC.24
This investigation identified the following variables potentially predictive of anlotinib efficacy: the concomitant use of PPI, nutritional risk score, monocyte percentage, grade IV histology, immunotherapy combination, and body temperature. A nomogram was subsequently constructed to forecast PFS in post-chemotherapy metastatic NSCLC patients. This prognostic tool generates individualised survival probabilities, facilitating personalised treatment strategies and identifying candidates for intensified surveillance or therapy modification.
However, this study has certain limitations. The single- centre, retrospective design potentially constrains the gene-ralisability of results and yields lower-level evidence compared to prospective approaches. The nomogram demonstrated consistent predictive performance at 6 and 12 months but may have limitations in predicting long-term outcomes. Additionally, due to insufficient data on the OS, the model is restricted to predicting PFS only.
CONCLUSION
This investigation identified prognostic factors influencing PFS among patients with metastatic NSCLC receiving anlotinib therapy. Based on these prognostic factors, a nomogram was developed to help clinicians predict PFS and guide clinical decisions, such as closer monitoring or treatment adjustments before and during therapy.
FUNDING:
This study was funded by the Young Medical Talents programme at Hefei Cancer Hospital, Chinese Academy of Sciences, Hebei, China.
ETHICAL APPROVAL:
This study was conducted with the approval of the Medical Ethics Committee of the Hefei Cancer Hospital, Chinese Academy of Sciences, Hebei, China (Ref. No: PJ-KY2024-042).
PATIENTS’ CONSENT:
All patients signed a general informed consent form upon admission, agreeing to the use of their medical record data for scientific research.
COMPETING INTEREST:
The authors declared no conflict of interest.
AUTHORS' CONTRIBUTION:
ZW: Experimental design, data analysis, and manuscript writing.
PZ, YZ: Experimental data extraction and data analysis.
JW: Experimental data extraction and manuscript writing.
SG: Data analysis and manuscript writing.
All authors approved the final version of the manuscript to be published.
REFERENCES