Recently, epidermal growth factor eceptor(EGFR) has been examined in many tumors such as lung cancer, breast cancer, brain tumor and stomach cancer. And it has been known to be associated with the development and progression of such tumors.
However,
there is no agreement of the expression of EGFR with clinical staging and the histological differentiation of colon cancer of which incidence is increasing progressively in Korea. This study was initiated to clarify the importance of expression
of
EGFR
on clinical staging and clinicopathologic parameters including the depth of invasion, the histologic differentiation of cancer cells, tumor site, tumor size and the blood level of carcinoembryonic antigen(CEA).
The expression of EGFR was examined immunohistochemically using monoclonal antibody against EGFR in total of 49 coon cancer tissues in the patients undertaken colectomy due to colon cancer and 10 metastatic lymph nodes in the same patients and 18
benign
tumors such as polyps and adenomas and 13 normal colon tissues in the patients undertaken colectomy due to traumatic colon injury or inflammatory disease.
The immunoreactivity of EGFR was detected in 36.7%(18/49) of the colon cancers, while it was observed in 5.6%(1/18) of the benign tumors, the incidence the two being significantly different(P<0.05). However, there was no expression of EGFR in
normal
colon tissues. And the immunoreactivity of EGFR in metastatic lymph nodes was detected in 40.0%(4/10) of the metastatic lymph nodes. The immunoreactivity of EGFR of human colon cancers was gradually increased from 12.5%(1/8) of Dukes-
Astler-Coller's
stage A, 22.2%(2/9) of stage B1, 16.7%(2/12) of stage B2, 42.9%(3/7) of stage C1 to 76.9%(10/13) of stage C2(P<0.05). And the immunoreactivity of EGFR was related to their depth of invasion of cancer cells(P<0.05). There was no relation between
the
immunoreactivity of EGFR, cancer size, cancer site and level of carcinoembryonic antigen(P>0.05). The EGFR was expressed only in moderately-differentiated cancers and well-differentiated cancers, while not expressed in poorly-defferentiated
cancers(P<0.05). The immunohistochemical staining intensity of EGFR was gradually increased according to clinical stages(P<).05).
These results suggested that the expression of EGFR may play an important role in the growth and differentiation of colon cancer. And the expression of EGFR using immunohistochemical stain was useful for diagnosis and treatment of colon cancer
and
it
also may serve as a prognostic indicator.(Korean J Gastroenterol 1994 ; 26 : 637-646)
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