Quantitative analysis of
DNA content and ploidy pattern was performed in 84 cases of
smooth muscle tumors of the gastrointestinal tract by flow cytometry, and the results were correlated with histopathologic features. The
aneuploid rate was found to be 0, 50%, 75%, 92.8% and 100% respectively in the
tumors with mitotic figures of 0,1, 2-4, 5-9, or over 10/10HPF (P < 0.005), as to be 3.2%, 60%, 95.8% and 100% in
tumors with zero, mild, moderate or severe cellular atypia (P < 0.005). There were no
aneuploidy in the 30 cases of
leiomyomas, but all 40 cases of
leiomyosarcomas were
aneuploidy, while in the 14 potentially malignant
smooth muscle tumors, there were 4 cases of
aneuploidy (P < 0.01). The
aneuploid rate was significantly higher in
tumors with contiguous organ inveasion or distant
metastasis (79.5%), and in
tumors of large size (64.5%) as well as in
tumors with center
necrosis (68.3%). 5 year survival rate in patients with
aneuploid tumors (41.6%) was significantly lower than those with diploid
tumors (96%) (P < 0.005). The results suggested that
DNA content and ploidy pattern be used as an objective parameter to distinguish malignants from benigns and predict the prognosis of patients with gastrointestinal
smooth muscle tumors.