Serum melatonin circadian profiles in women suffering from cervical cancer.

Although there is an increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors. Therefore, we decided to study the circadian melatonin rhythm in patients suffering from cervical cancer in different stages of progression and to compare them with those in subjects free from neoplastic disease. A total of 45 women were analyzed in this study. The subjects were divided into two groups. The first group consisted of 31 patients [mean age 52.1 +/- 1.8 yr (mean +/- S.E.M.), range 32-77 yr] with cervical cancer in various stages of the disease. The second group consisted of 14 healthy volunteers [mean age 53.5 +/- 2.0 yr (mean +/- S.E.M.), range 42-63] who served as the control group. Blood samples were collected at 08:00, 12:00, 16:00, 20:00, 22:00, 24:00, 02:00, 04:00, 06:00, and 08:00 hours. Melatonin concentration was measured by immunoenzymatic method. There were significant differences in circadian melatonin profiles as well as in the area under curve among the two studied groups. Melatonin concentrations were significantly lower in cancer patients in comparison with healthy individuals. Taking into consideration stage of the cervical cancer significantly lower melatonin secretion has been found in all subgroups of patients in comparison with that of tumor-free control group. Additionally, nocturnal melatonin concentrations as well as area under curve were significantly lower in advanced stage of cancer (stages 3 and 4) in comparison with patients with preinvasive cancer (stage 0) at 24:00, 02:00, and 04:00 hours and patients with stage 1 disease at 02:00 and 04:00 hours. The results of the present study indicate that the presence of cervical cancer influences melatonin levels in women. Moreover, stage dependence in reduction of melatonin concentrations has been found.

Serum melatonin circadian profile in women suffering from the genital tract cancers.

OBJECTIVES: Although there is increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors. Therefore we decided to study the circadian melatonin rhythm in patients suffering from malignant tumors of the female genital tract, and to compare them with subjects free from neoplastic disease (healthy volunteers and patients with myomatous uterus). MATERIAL AND METHODS: A total of 46 women were analyzed in this study. The subjects were divided into 3 groups. The first group consisted of 23 patients with malignant tumors of the genital tract (mean age 50.3+/-2.2 years; mean+/-SEM, range 32-77 years). The second group consisted of 16 healthy volunteers (mean age 50.9+/-1.8 years; mean+/-SEM, range 42-63) who served as the first control group, whereas the third group consisted of 7 subjects who suffered from myomatous uterus (mean age 45.7+/-2.3 years; mean+/-SEM, range 39-56) and served as the second control group without malignancy. Blood samples were collected at 08:00, 12:00, 16:00, 20:00, 22:00, 24:00, 02:00, 04:00, 06:00 and 08:00 h. Melatonin concentration was measured using RIA kit. RESULTS: There were no significant differences in circadian melatonin profiles among the three groups studied. Taking into consideration the type of tumor of the genital tract, significantly lower melatonin secretion has been found in patients with endometrial cancer in comparison with tumor-free control groups, whereas no significant differences in melatonin secretion have been observed between tumor-free control groups and patients with invasive ovarian cancer and squamous cervical cancer. However, significant differences have been observed between endometrial cancer and invasive ovarian cancer. CONCLUSION: Its seems probable that melatonin concentrations in human malignancy may, at least partly, depend on hormone dependency of the particular type of tumor.