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Published on: January 19, 2018
Direct Observation of Retinal Microvessels in Cancer Patients After Systemic Administration of Bevacizumab and
Ayako Mitsuma1, Yasuki Ito2,3, Tomoya Shimokata1
1Department of Clinical Oncology and Chemotherapy, Nagoya University Hospital, Nagoya, Japan.
Background/Aim:
Antiangiogenic chemotherapy is the backbone of the various anticancer therapies. To date no practical biomarker predicting their antitumor effects and toxicity has been reported. We aimed to determine the feasibility of direct retinal observation as a practical biomarker in antiangiogenic chemotherapy.
Patients And Methods:
By direct retinal observation using a nonmydriatic retinal camera, we measured retinal microvessel diameters in 10 patients with colorectal cancer before and after intravenous infusion of bevacizumab and oxaliplatin. All patients also received oral capecitabine during their therapy.
Results:
Retinal microvessel diameters were decreased from baseline temporarily by 14.5±6.5% after infusion of bevacizumab and oxaliplatin in five patients who responded to treatment and 8.8±6.2% in the other five patients (p=0.008).
Conclusion:
Measurement of retinal microvessel diameters by direct observation appears to be feasible in patients receiving systemic chemotherapy. The decrease of retinal microvessel diameters might indicate improved tumor response to treatment with bevacizumab-containing systemic chemotherapy.
Insights
Direct retinal observation may predict antiangiogenic chemotherapy effectiveness. Measuring retinal microvessel diameter changes offers a practical biomarker for cancer treatment response.
Area of Science:
- Oncology
- Ophthalmology
- Biomarker Discovery
Background:
- Antiangiogenic chemotherapy is a cornerstone of cancer treatment.
- Currently, no reliable biomarkers predict treatment efficacy or toxicity.
- There is a need for practical predictive biomarkers in antiangiogenic therapy.
Purpose of the Study:
- To assess the feasibility of direct retinal observation as a biomarker.
- To evaluate retinal microvessel diameter changes during antiangiogenic chemotherapy.
Main Methods:
- Retinal microvessel diameters were measured using nonmydriatic retinal cameras.
- Measurements were taken before and after chemotherapy in 10 colorectal cancer patients.
- Bevacizumab, oxaliplatin, and capecitabine were administered.
Main Results:
- A significant decrease in retinal microvessel diameters was observed post-chemotherapy (p=0.008).
- Responders showed a 14.5% decrease, while non-responders showed an 8.8% decrease.
- Retinal microvessel diameter reduction suggests a potential link to treatment response.
Conclusions:
- Direct retinal observation is a feasible method for monitoring chemotherapy patients.
- Decreased retinal microvessel diameter may indicate a positive response to bevacizumab-based chemotherapy.
- This technique could serve as a practical predictive biomarker for antiangiogenic therapy.
