Evaluation of Retinal Nerve Fiber Layer and Macular Thickness Pre- and Post-Chemotherapy With Carboplatin and Paclitaxel in Patients With Endometrial and Ovarian Cancer

Abstract

Background Carboplatin and paclitaxel are two standard chemotherapeutic agents known to cause neurotoxicity. In this study, we aim to evaluate the toxicity of these agents by measuring the peripapillary retinal nerve fiber layer (RNFL) and macular thickness in patients with endometrial and ovarian cancers who are receiving them. Methods A one-year prospective cohort study involving 28 patients who were treated intravenously with carboplatin (200-400 mg/m²) and paclitaxel (175 mg/m²) three-weekly for six cycles was conducted. RNFL and macula thickness were measured using optical coherence tomography (OCT) before the commencement of chemotherapy, after the third cycle, and one month after the sixth cycle. The main outcome measurements were the average RNFL thickness and central subfield thickness of the macula. Results The mean age of the 28 participants was 54.68 years old (standard deviation [SD] 9.03). Eleven had endometrial cancer, while 17 had ovarian cancer. The mean of the average RNFL thickness during baseline pre-chemotherapy was 96.43 µm (SD 11.39). One month after cessation of treatment, the mean RNFL thickness increased to 101.57 µm (SD 13.54). Statistical analysis showed a significant increment in the mean RNFL thickness (p ≤ 0.001), from baseline to after three cycles, and baseline to one month after six cycles of chemotherapy, except the nasal quadrant. The increment of all macular quadrants was statistically significant (p < 0.05) except for central subfield thickness. Conclusion Systemic administration of carboplatin and paclitaxel affected both the peripapillary RNFL and macula thickness. This represents early evidence of subacute subclinical retinal toxicity. OCT can be used as a screening tool to assess peri-chemotherapeutic retinal alterations.

Keywords: carboplatin; macular thickness; ocular toxicity; paclitaxel; retinal nerve fiber layer.

Figure 1. Mean of RNFL thickness with time

1: Average; 2: Superior; 3: Inferior; 4: Temporal; 5: Nasal. RNFL: Retinal nerve fiber layer.

Figure 2. Mean of macular thickness with time

1: Macular central subfield thickness; 2: Inner superior; 3: Inner nasal; 4: Inner inferior; 5: Inner temporal; 6: Outer temporal; 7: Outer superior; 8: Outer nasal; 9: Outer inferior.