Serum Malondialdehyde as a Biomarker of Oxidative Stress in Patients with Primary Ocular Carcinoma: Impact on Response to Chemotherapy

Purpose: To study the level of serum malondialdehyde (MDA), a biomarker of oxidative stress before and after chemotherapy in various ocular malignancies and to correlate its significance with clinicopathological parameters. Methods: Thirty two histopathologically confirmed cases of primary ocular malignancies were included in this longitudinal cohort study. Detailed clinicopathological assessment was done. Analysis of serum MDA level in the patient before and after chemotherapy was measured and its prognostic significance was analyzed. Results: Maximum cases were of eyelid malignancy (n=18, 56.2%) followed by retinoblastoma (18.8%) and OSSN (6, 18.8%). About 43.75% patients were in the advanced-stage. The tumor was histopathologically well-differentiated in 20 (62.5%) cases. Most common malignancy was sebaceous gland carcinoma of the eyelid (n=10,31.25%). Serum MDA level in patients were significantly higher than controls [5.5712 +/- 0.32779 vs 2.5531 +/- 0.08056 nmol/ mL, p<0.001]. Level was significantly reduced after chemotherapy (4.5146 +/- 0.23209 nmol/mL). Serum MDA was maximum in cases of rhabdomyosarcoma (5.9450 +/- 0.23335 nmol/mL) and retinoblastoma (5.7433 +/- 0.14334 nmol/mL). It was minimum in basal cell carcinoma (5.3775 +/- 0.17746 nmol/mL). Pre chemotherapy serum MDA level was significantly higher in patients having larger tumor (>20mm, p< 0.001) and having lymph node metastasis than those without lymph node metastasis [5.8350 +/- 0.17113 vs 5.4833 +/- 0.32193 nmol/mL, p<0.006]. No significant difference was observed in post chemotherapy serum MDA level as for as size of tumor (p=0.947) and histopathological differentiation (p=0.109) was concerned. Conclusion: The serum MDA level is a potential biomarker in primary ocular carcinoma to assess oxidative stress and its impact on response to chemotherapy.