ABSTRACT
<p><b>BACKGROUND</b>According to the National Institutes of Health consensus criteria, gastrointestinal stromal tumors (GISTs) smaller than 2 cm in diameter with less than 5 mitotic figures per 50 high-power fields are considered very-low-risk GISTs, but these two indices alone cannot reliably predict a benign outcome during long-term follow-ups. Therefore, identification of additional parameters for predicting the clinical behavior of GISTs is necessary.</p><p><b>METHODS</b>Eighty-eight patients with tumors that meet the very-low-risk GIST criteria were retrospectively investigated and morphological parameters of tumors associated with the biological behavior of very-low-risk GISTs were evaluated in the present study. The Kaplan-Meier method was used to calculate disease-free survival rates.</p><p><b>RESULTS</b>Eighty-one patients were followed up for one to 16.3 years. Five cases of relapses were identified in the patients. Distinctive infiltrative growth patterns such as muscularis propria, muscularis mucosa, or nerve infiltration were identified by microscopy in 4 patients with the relapse, including three patients who experienced multiple recurrences. The infiltrative growth features became more obvious in multiple recurrent tumors compared to the single recurrent tumor, while only one developed relapse in 76 patients without infiltration (P < 0.0001).</p><p><b>CONCLUSION</b>Microscopic infiltrative growth patterns of the tumor may have clinical significance in predicting the prognosis of very-low-risk GISTs.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Disease-Free Survival , Gastrointestinal Stromal Tumors , Pathology , Prognosis , Retrospective StudiesABSTRACT
<p><b>BACKGROUND</b>Hypoxia-inducible factor (HIF) may play an important role in the process of tumorigenesis as well as tumor progression. The aim of this study was to compare the expression between HIF-1α and HIF-2α in tumor angiogenesis and the overall impact on patient prognosis in human non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>In the current work we compared the immunohistochemical expression of HIF-1α and HIF-2α in surgical specimens of 140 patients with NSCLC in a tissue microarray study. Relationships between HIF-α expression and clinicopathological or angiogenic factors, including prognosis, were analyzed.</p><p><b>RESULTS</b>High HIF-1α and HIF-2α expression was noted in 49/140 (35.0%) and in 64/140 (45.7%) of the cases, respectively. There was no direct correlation between HIF-1α and HIF-2α expression. Patients with advanced stage tumors had frequent high expression of HIF-2α (P = 0.007), and we also found a significant correlation between HIF-2α and T or N stage (P = 0.030 and 0.043, respectively). HIF-1α showed a marginal association with T stage (P = 0.084), which showed a higher expression in early stage tumors. A significant correlation (P = 0.045) was noticed between HIF-1α and vascular endothelial growth factor (VEGF) expression while the expression levels of thymidine phosphorylase (TP), cyclooxygenase (COX)-2 and microvessel density (MVD) were significantly higher in high HIF-2α tumors (P = 0.020, 0.004, and 0.046, respectively). In addition, univariate analysis of overall survival demonstrated that HIF-2α expression, but not HIF-1α, was related to poor outcome (P = 0.001) and it retained significant in multivariate analysis (P = 0.036).</p><p><b>CONCLUSIONS</b>Taken together, we conclude that HIF-1α and HIF-2α may differentially regulate the major angiogenic factors in different stages of the tumor process in NSCLC. HIF-2α may play a dominant role in tumor angiogenesis and appears to be of obvious value as a significant prognostic factor in NSCLC.</p>