الفهرس 
Review of LiteratureOnly 14 pages are availabe for public view
 |  | from | 239 |  |  |
| | | from | 239 | | |
Abstract
Summary & Conclusion ””
SUMMARY AND CONCLUSION
Summary:
In Egypt, colorectal cancer is the seventh most common cancer
according to Cancer Pathology Registry (Soliman et aL, 1997). In United
States, colorectal carcinoma is the second most common malignancy after
lung cancer, comprising 10-15% of all malignancies. It shows wide
variation in incidence throughout the world (Potter, 1997).
The present study aims at evaluation of the proliferative activity of
different histopathologic colorectal tumors among Egyptians. Tumor
were classified according to WHO classification, using two different
methods of cellular proliferation; the monoclonal antibody PCNA LI and
silver-stained nucleolar organizer regions. The second aim was to
correlate their results with other clinicopathologic variables including
age, sex, site, metastases, grade, stage, and depth of invasion, recurrence
and survival. Statistical analysis and correlations were made for all these
variables.
Our material of study included 46 cases of colorectal tumors which
were diagnosed and treated at the Faculty of Medicine Benha University
and the Armed Forces hospital during the period between July 1990 and
January 1995. All of the patients underwent resection of the tumor
combined with lymph node dissection and none of them received preoperative
chemotherapy or radiotherapy. Additional 6 normal colonic
specimens were taken as a control.
166
Summary & Conclusion ~
The PCNA Labeling Index (PCNA-LI) was determined as the
percentage of positive cell nuclei. Cases were then classified into high
and low PCNA LI according whether the value was above or below the
median PCNA LI. Also AgNOR score was divided into low and high
according to the mean. Morphology and distribution of AgNOR was
taken into consideration.
Statistical analysis was performed by the student ”t” test, the chi
square test and the Fisher exact probability calculation method. The
correlation between PCNA LI and AgNOR score was studied using linear
regression. The outcome of different groups of patients was compared by
the generalized Wilcescan test. Statistical significance was defined as
P<0.05.
The histopathologic findings showed that out of 46 cases studied, 4
cases adenoma, 42 cases colorectal cancer; including 8 WDA, 12 MDA, 7
PDA, 9 MUC and 6 SRC. Also, we added 6 cases as a control. Lymph
node, liver and peritoneal metastases were detected in 21, 13 and 7 cases
respectively. Out of the 42 colorectal cancer, 23 had recurrence and 22
died. Eleven cases were stage Bl, 9 stage B2, 5 stage Cl, 11 stage C2 and
4 cases stage D.
The immunohistochemical results of PCNA LI varied between
different colorectal groups, where it increased gradually with progression
and proliferation of the lesions from apparently normal mucosa (1.33 +
1.2) to adenoma (20.25 ± 3.3) to colorectal cancer (46.9 ± 23.44), where
167
Summary & Conclusion ’”
P<O.00 1. PCNA LI was found to correlate well with tumor stage, depth of
invasion, metastases and survival. The prognosis of high PCNA group
was significantly worse than that oflow PCNA group, P<O.OOl based on
survival and metastases.
The AgNOR counts were found to correlate significantly and
increase gradually with progression of colorectal lesions. The mean
numbers of AgNORs dots/nucleus was evaluated in apparently normal
mucosa (1.97 + 0.51), in adenoma (3.28 + 0.8) and in colorectal cancer
(5.6 + 1.95), where P<O.OO1.An overlap was found between individual
cases of the malignant groups. The AgNOR score was found to correlate
well with tumor stage, depth of invasion, metastases and recurrence. The
prognosis of high AgNOR group was significantly worse than that of the
low AgNOR group, P<O.OOl.
As regards the AgNOR morphology and distribution pattern, it was
found to show a characteristic difference between benign and malignant
groups of colorectal tumors. Malignant cells were characterized by an
irregularly scattered distribution ofNORs and by a pleomorphic size and
shape of the dots in comparison to the rounded, uniform and regular size
and shape with regular dispersion in the nucleoplasm of the NORs dots in
benign lesions.
from the combined analysis of AgNOR score and PCNA LI, we
found that the high AgNOR, high PCNA group had the poorest
prognosis, on the other hand low AgNOR, low PCNA group had the best.
We suggest that nucleolar organizer regions were the most reliable
168
Summary & Conclusion l<1
prognostic variable for predicting recurrence irrespective to PCNA. While
PCNA could be more accurate in predicting survival. These results
indicate that simultaneous determination of AgNOR score and PCNA LI
is more serviceable than either alone for the precise evaluation of
prognosis for colorectal carcinoma patients.