[Gastrointestinal stromal tumors: prognostic value of DNA analysis with flow cytometry and of classical clinicopathologic parameters].

BACKGROUND

Biological behavior of gastrointestinal stromal tumours (GIST) is still difficult to predict. The aim of this study was to analyze the prognostic valve of DNA study by flow cytometry in addition to the classical clinicopathologic parameters.

PATIENTS AND

METHODS

82 GIST were investigated to assess by multivariable analysis the prognostic significance of classical morphologic and clinical features and DNA flow-cytometric analysis.

RESULTS

Features significantly correlated with bad prognosis were: pain, recurrences, metastasis, small intestine tumours, invasion of adjacent tissues, size > 6 cm, infiltrative pattern, high cellularity, high-grade of atypia, mitosis count > 2/50 high powered field, necrosis, DNA aneuploid-hyperploid or near-diploid, S and SG2M-phase of aneuploid/s population/s > 11% and average S-phase > 11%. Multivariable analysis showed that mitotic activity was the only independent variable indicating poor prognosis.

CONCLUSIONS

In this series of GIST mitosis count was the only independent prognostic factor, being more important than flow-cytometric variables like DNA ploidy and cellular cycle values.