BACKGROUND: Long non-coding RNAs (lncRNAs) are a kind of single-stranded RNA of more than 200 nucleotides in length and have no protein-coding function. Amounting studies have indicated that lncRNAs could play a vital role in the initiation and development of cancers, including gastric cancer (GC). Considering the crucial functions of lncRNAs, the identification and exploration of novel lncRNAs in GC is necessary.
AIM: To identify independent prognostic markers for the whole gastroenteropancreatic neuroendocrine tumor (GEP-NET) group.
METHODS: Ninety-three patients diagnosed with GEP-NETs within a specified period were included in this study. Patient data were retrospectively analyzed. The relationships between all independent variables and 5-year survival status calculated during the follow-up period (months) were assessed. In addition, the relationships between the independent variables were investigated.
RESULTS: When 5-year survival rate was compared, a statistically significant relationship between the age at diagnosis, male gender, tumor size, tumor stage, liver and/or distant metastasis, and tumor grade determined by the Ki-67 level and mitotic count, and the level of C-reactive protein (CRP), was observed. The mean survival (overall survival) of the study group was 102.5 ± 6.3 (SD) mo. The percentages of 1, 3 and 5-year survival were 90%, 72%, and 61%, respectively. In 63 of 93 patients, Ki-67 and the mitotic count determined the same grade. The Ki-67 levels in 29 patients and the mitotic count in only 1 patient were in the higher grade. The risk of death increased by 4% for every 1 year increase at the diagnosis age and was 2.0-fold higher for male patients, 3.0-fold higher for G3 according to the mitotic count, 3.7-fold higher for G3 according to the Ki-67 level, 12.7-fold higher for cases with tumor stage 3 or 4 by a 1 cm increase in the ratio of 9% in tumor size, and 6.1-fold higher for patients with liver metastasis for every 1 mg/dL increase in the ratio of 1.5% in CRP level. There was a significant difference between pancreatic and stomach NETs in favor of stomach tumors in terms of survival.
CONCLUSION: Tumor site, stage, grade and Ki-67 level affected patient survival, and it was observed that CRP affected disease progression (particularly if it was > 20 mg/dL). However, a relationship between surgical resection of the lesion and survival was not shown. Larger scale prospective studies are required to determine whether CRP level may be a poor prognostic factor for the entire GEP-NET group.
