The association of stromal mast cell response and tumor cell differentiation in colorectal cancer.

ABSTRACT

BACKGROUND: Resembling other neoplasms, the colorectal carcinogenesis is still a riddle in various aspects. Mast cells, a type of inflammatory cells, may play a role in colonic cancer pathogenesis. It has recently been found to have an essential function in tumor development and its immunologic response. OBJECTIVE: To evaluate the relation between mast cell number and biology of colorectal adenocarcinoma. MATERIAL AND METHOD: The author collected 162 cases, diagnosed as primary adenocarcinoma of the colon at the King Chulalongkorn Memorial Hospital, between 2002 and 2003, for evaluating the role of mast cells in colorectal cancers. The hematoxylin and eosin stained sections were reviewed and classified into the tumor differentiation or grading, depth of tumor invasion, and status of regional lymph node metastasis, according to the World Heath Organization's (WHO) criteria. Mast cell number within and around the tumor was counted on the 0.1% toluidine blue stained sections. F-test was used to correlate between the mast cell quantity and aforementioned tumor parameters. RESULTS: The tumor differentiation consisted of grade 1 (34%), grade 2 (52%) and grade 3 (14%), with a mean of mast cell number of23, 32 and 40 cells/mm2, respectively. In addition, mast cell quantity in poorly differentiated tumors was significantly higher than those in well differentiated form (p = 0. 03). Therefore, mast cell number was not correlated with tumor depth (p = 0.28) and nodal status (p = 0. 75). CONCLUSION: This observation might indicate that mast cell function has a role in colorectal pathogenesis.