Evaluation of the Prognostic value of the Prechemotherapy Platelet to Lymphocyte Ratio in Malignant Pleural Mesothelioma
Background: Malignant pleural mesothelioma is an aggressive disease. It is characterized with bad prognosis. We conducted this study to assess the prognostic significance of pretreatment PLR in patients with MPM. Methods: We retrospectively reviewed 400 patients treated for MPM in Ain Shams University hospital, Clinical Oncology department between January 2013 and December 2017. Pre-treatment CBC was available for the 110 patients to calculate PLR. Results: Out of 110 patients, age ranged from 28 to 70 years. Male: female was 5: 6. Epithelioid subtype represent 85%. Stages III, IV represent 48.2% and 35.5%. Median PFS and OS were 6.9 and 11.9 months. Using a cut-off value of 177.9. Low PLR was associated with better median PFS than high PLR (7.97 vs. 6.63), (p=0.039). For patients with low vs. high PLR, median OS was 15.07 vs. 10.4 months (P value= 0.063) 61.8% received platinum pemetrexed and 38.2% received platinum/gemcitabine as 1st line chemotherapy. Radiological response to first line therapy was SD, PR, PD and CR in 47%, 29%, 23% and 0.9% of patients respectively. There was no statistical significance in PFS and OS between patients who received platinum/pemetexed versus platinum/Gemcitabine (p=0.53). The group who received platinum/pemetrexed had median OS 17.5 vs. 10.5 months (P=0.108) in low versus high PLR and median PFS 7.7 months vs. 5.03 months (P=0.034). The group who received platinumgemcitabine had median OS 15.07 vs. 8.2 months (P=0.264) in low versus high PLR and median PFS 8.07 vs. 8.2 months (P=0.332). Conclusion: The higher the PLR, the worse the prognosis. There was statistically significant difference in PFS between low vs. high PLR, and in PFS of both groups of PLR of the group who received platinum pemetrexed.