Utility of clinical and MR imaging parameters for prediction and monitoring of response to capecitabine and temozolomide (CAPTEM) therapy in patients with liver metastases of neuroendocrine tumors

Maria Ingenerf ¹, Christoph Auernhammer ^2,3, Roberto Lorbeer ¹

⁰Department of Radiology, University Hospital, LMU Munich, Germany.

Radiology and Oncology +

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April 13, 2024

View abstract on PubMed

Summary

Magnetic resonance imaging (MRI) parameters, including apparent diffusion coefficient (ADC) values and tumor size, effectively predict capecitabine and temozolomide (CAPTEM) therapy response in neuroendocrine tumors (NET). Combining these MRI metrics with clinical markers like chromogranin A (CgA) improves monitoring accuracy.

Area Of Science

Oncology
Radiology
Medical Imaging

Background

Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms.
Capecitabine and temozolomide (CAPTEM) is a common treatment regimen for NETs, particularly those with liver metastases.
Accurate assessment of treatment response is crucial for optimizing patient management.

Purpose Of The Study

To evaluate the predictive and monitoring capabilities of multiparametric MRI parameters in assessing CAPTEM therapy response in NET patients.
To compare the efficacy of different MRI-derived metrics and clinical parameters in predicting progression-free survival (PFS).
To establish optimal response criteria for monitoring CAPTEM treatment in hepatic NET metastases.

Main Methods

Retrospective analysis of 44 neuroendocrine liver metastases (NELM) patients treated with CAPTEM.
Pretherapeutic and follow-up MRI data (tumor size, apparent diffusion coefficient [ADC] values) and clinical parameters (chromogranin A [CgA], Ki-67%) were analyzed.
Progression-free survival (PFS) ≥ 6 months defined responders; analysis included ROC and Kaplan-Meier curves.

Main Results

Non-responders (NR) exhibited higher primary tumor Ki-67 and increased hepatic burden compared to responders (R).
Post-treatment CgA levels were elevated in NR and decreased in R.
Significant differences in ADC changes were observed: NR showed decreased ADCmin and liver-adjusted ADCmean, while R showed increases. A combined model of ∆ Size NELM and ∆ ADCmin demonstrated high sensitivity (88%) and specificity (60%) for predicting response.

Conclusions

Multiparametric MRI, particularly ADC values and tumor size changes, are valuable tools for monitoring CAPTEM response in hepatic NETs.
Combined evaluation of CgA, ADC values, and tumor size offers a more robust approach to response assessment.
Adapted response criteria incorporating these parameters are needed for improved patient management.

Keywords:

CAPTEM therapy MR imaging clinical parameters liver metastases neuroendocrine tumors treatment response