Ki-67 proliferation index and clinicopathological patterns in colorectal carcinomas

Background : Tumour, node, metastasis (TNM) staging system provides useful prognostic information in patients with colorectal carcinoma (CRC). An improved prognostication and patient survival may be achieved by employing immunohistochemistry studies with proliferation markers like Ki-67. Material and methods: We prospectively studied 51 patients with CRC and evaluated the clinicopathological patterns of CRC and the relationship of with the clinicopathological variables Results: Their mean age was 48 (range 17-75) years; majority (64.7%) were males. Rectum was the most common subsite affected (45.1%). Histopathologically most of the tumours (86.3%) were usual type adenocarcinomas and were of grade 1 morphology (51%). The Ki-67 proliferation index (PI) ranged from 8.4% to 84.4%. The mean PI was greater in patients aged less than or equal to 50 years than in those aged above 50 years, in males than females, in rectal cancers than colonic cancers. It was greater in mucinous carcinomas than usual type adenocarcinomas, in grade 3 tumours than lower grade tumours (grades 1 and 2) and in T4 than T3 and T2 tumours. There was a significant positive correlation between the PI values and grade of the tumour. Conclusion: We concluded that Ki-67 proliferation marker may be useful as an additional tool to assess the tumour aggressiveness with respect to certain clinicopathological parameters in colorectal carcinomas.