SUMMARY
Cancer is heterogeneous disorders characterized by cellular different genetic alterations and diverse clinical behaviours results from uncontrolled division leads to loss of control of the cells growth. Neuron Specific Enolase(NSE) is considered as a marker of many diseases such as brain damage (traumatic brain injury), stroke and anoxic encephalopathy after cardiac arrest. Generally, in adults NSE accepted as a marker protein in the brain. Serotonin exhibits a growth stimulatory effect on several types of carcinoma, carcinoid and other tumor cells. In contrast, a few data are available on serotonin involvement in cancer cell migration and metastatic processes. Serum serotonin level was found to be suitable for prognosis evaluation of urothelial carcinoma in the urinary bladder, adenocarcinoma of the prostate and renal cell carcinoma. 201 patients with malignant tumors, 74 patients with different benign tumors and, 83 healthy individuals were enrolled in the present study. Our results show a significant increase (p = 0.011, and 0.043) of serum serotonin levels in malignant tumors group when compared with those of benign tumors (as a pathological control) group, and healthy individuals groups; respectively. No such results were shown when the two control (benign tumors and healthy individuals) groups were compared together. While evaluation of the NSE concentrations revealed a significant decrease in patients with malignant tumors when compared with those of benign tumors (p = 0.028), and healthy individuals (p< 0.000). According to ANOVA test, Same variations (p < 0.000) were obtained when benign tumors and healthy controls groups were compared together. Results shows a significant decrease in the serotonin concentration (p < 0.05) as well as the NSE (p < 0.01) levels, correlation between the levels of the two examined parameters has been negative and statically acceptable (r = - 0.723 at p<0.05) at malignant tumor patients group after treatment by chemotherapy or radiotherapy. Before treatment with chemotherapy or radiotherapy, negatively significant correlation (r = - 0.792 at p < 0.001) was observed for the concentrations of Serotonin to the NSE in the sera of malignant tumor patients group, while no such correlations were noted at this relation examined in the benign tumor patients. Serotonin and NSE correlations together can be used as primary diagnostic tools for distinguishing between cancerous and benign tumors, this correlation increases the sensitivity of the two biomarkers together comparing to measure everyone alone.