Aims: Chromogranin-A (CG), a cytoplasmic glycoprotein, is one of the m
arkers most frequently used to identify the presence of neuroendocrine
cells in the human gastrointestinal tract. Several authors have ident
ified a subgroup of colorectal cancer patients with a severe prognosis
whose tumors contained neuroendocrine CG-positive cells. In the prese
nt study, CG expression in 100 patients with colorectal adenocarcinoma
treated from January 1983 to December 1988 with potentially curative
surgery was analyzed and correlated with other prognostic factors and
5-year survival rate, Methods: Samples tested immunohistochemically fa
r CG were divided into three groups: I) negative; II) less than 1 CG-p
ositive cell/mm(2); III) more than 1 CG-positive celll/mm(2). Results:
Of 100 patients with primary colorectal adenocarcinoma, 79% had tumor
s comprised of CG-negative cells, 17% had rare CG-positive cells, and
4% of cases could be classified in group III. No significant relation
between CG expression and location of primary tumor, bowel wall infilt
ration, stage of disease or tumor grade according to Broders and Jass
was observed. The 5-year survival was 53% and 52% for CG-positive acid
CG-negative lesions, respectively. Survival of patients with Dukes-Ki
rklin stage C and D was comparable in patients with CG-positive (33.3%
) and CG-negative (30%) tumors. Conclusions: CG expression cannot, at
present, be recommended as a marker to identify prognostic subgroups i
n colorectal cancer patients.