Hepatoma-derived growth factor is a novel prognostic factor for gastrointestinal stromal tumors

Proliferating activity as mitotic count is generally accepted as a major prognostic indicator for gastrointestinal stromal tumors (GISTs). Hepatoma-derived growth factor (HDGF) is a novel growth factor and elevated in several types of cancer. Our study was designed to elucidate the expression and prognostic role of HDGF in GISTs. A total 178 surgically resected CD117-positive GISTs specimens were collected for immunohistochemical analysis using antibodies against HDGF. The immunoreactivities were scored as labeling index (LI) and correlated with clinicopathologic parameters of GIST patients. The HDGF immunoreactivities were detected in both nucleus and cytoplasm of GISTs tissues. Besides, the nuclear and cytoplasmic HDGF was parallely upregulated in GISTs (p < 0.001). The nuclear HDGF LI were positively correlated with that of PCNA (p < 0.001) and Ki-67 (p < 0.001), tumor mitosis (p < 0.001), tumor sizes (p = 0.007) and NIH risk categories (p < 0.001). In addition, the cytoplasmic HDGF LI were also positively correlated with that of PCNA (p = 0.031) and Ki-67 (p = 0.038), tumor sizes (p = 0.003) and tumor mitosis (p = 0.015). Patients with higher HDGF levels had earlier tumor recurrence and unfavorable outcome (p < 0.05). In addition to standard prognostic factors (NIH risk categories), the nuclear HDGF LI is an independent prognostic factor for disease free and overall survivals of GIST patients after operation. We conclude that HDGF is a novel prognostic factor for GIST patients.