The correlation of Ki-67 (MIB-1) proliferation index and progesterone receptor status with histological grade of meningioma: An observational study

Context: Five year rate for recurrence of symptoms regardless of method of treatment is 19.2% for benign tumors and 32.4% for malignant tumors. Behavior of meningiomas depends upon its histological type, grade, proliferation markers and PR status. Aims: To correlate the WHO grade, PR status and Ki-67 labeling index of meningiomas to correlate with other histologic and demographic parameters of prognostic significance. Material and methods: A total of 120 cases were taken over a period of 2 years. Routine H&E stain sections used for histological typing and grade of meningioma. Immunohistochemistry done for Ki-67 and Progestrone receptor using immunoperoxidase method. The various grades of meningiomas than correlated with Ki-67 labeling index and PR status and appropriate statistical calculations done. Results: The peak age distribution is between 31 to 50 years with mean age of 49.45 years, male to female ratio being 1:2.3. Maximum cases were of grade I (88.33%) followed by grade II(6.66%) and grade III(5%). There was no significant difference between mean age of different grades (p>0.05). The difference between mean Ki-67 labeling index between grade I and II, grade II and III and grade I and III all were significant (p<0.0001). The PR status difference between grade I and II tumor was significant (p=0.0007), however between grade II and III could not be calculated as none of these tumor showed PR positivity. The Pearson correlation coefficient between PR status with Ki67 labeling index came out to be -1.0, that shows highly significant negative correlation. Conclusion: This study shows an inverse correlation between WHO 2016 grades of meningioma and PR status while shows a linear relation with Ki-67 labeling index