We analyzed the proliferative activities, immunoreactivity of the p53
protein, and
aneuploidy in patients with benign and malignant fibrous lesions, including 19 with nodular
fasciitis (cellular type) (6-88 years old, mean 42.9), 11 with
abdominal fibromatoses (22-74 years old, mean 37.9), 13 with extraabdominal
fibromatoses (2-38 years old, mean 19.5), and 23 with
fibrosarcomas (adult type: 16-71 years old, mean 47.3; infantile type: 3 months to 9 years, mean 2.9) using immunohistochemistry to determine
proliferating cell nuclear antigen (PC10) and p53
protein (CM1) as well as performing
DNA flow cytometry. The
proliferating cell nuclear antigen (
PCNA) score was measured as the ratio of
PCNA-positive nuclear size/total nuclear size determined by an image analysis computer system. The distribution pattern of the
PCNA-positive cells was uneven in each instance of nodular
fasciitis, in contrast to the distribution in
abdominal fibromatosis, extraabdominal
fibromatosis, and
fibrosarcoma. Both
fibrosarcoma (28.4 +/- 20.0) and nodular
fasciitis (33.6 +/- 20.9) exhibited a larger value and a greater variation in the
PCNA score than did either abdominal (13.5 +/- 14.5) or extraabdominal
fibromatosis (19.9 +/- 21.5).
Abdominal fibromatosis exhibited a smaller value and less variation in the score. In short, the
PCNA score did not correlate with the malignant potential. The proliferative index (S + G2 + M fraction) in
fibrosarcoma was significantly higher than in either nodular
fasciitis or
abdominal fibromatosis.
Aneuploidy was detected in five cases (26%) of
fibrosarcoma, while six (26%)
fibrosarcomas showed p53 positivity. Furthermore, p53-positive patients had a worse survival (0.01 < p < 0.05), and p53 positivity correlated with the proliferative index (p < 0.01). In conclusion, the
PCNA score simply indicates the proliferative activity independent of malignant potential. On the other hand, p53 positivity, proliferative index, and
aneuploidy are all indicators of malignant potential in fibroblastic lesions, and p53 positivity may reflect a poor prognosis.