Disappearance Curves of Tumor Markers after Radical Surgery

CEA serum levels were sampled from 15 patients with lung carcinoma, 12 patients with colon carcinoma, and 5 patients with gastric carcinoma before and after radical excision of the malignancy. In addition, TPA serum levels were measured in 7 patients with lung carcinoma and CA 19.9 serum levels in 9 patients with colon carcinoma, before and after curative surgery. Irrespective of the primary malignancy, a CEA half-life of approximately 3 days was calculated. The normalization time was related to the preoperative level of the marker, being longer when the preoperative CEA level was > 20 ng/ml. The TPA half-life was slightly longer than 1 day, ranging from less than 1 day to more than 3 days, with a normalization time of about 20 days. The CA 19.9 half-life was slightly longer than 1 day with variations from less than 1 day to about 3 days. Many factors, especially associated inflammatory processes and hepatic clearance imbalances, may influence marker kinetics in the postoperative period. A correct evaluation of the clinical significance of tumor marker half-life after radical surgery will require a larger number of patients as well as careful and prolonged follow-up.

Obese patients with obstructive sleep apnoea syndrome show a peculiar alteration of the corticotroph but not of the thyrotroph and lactotroph function

OBJECTIVE

Obstructive sleep apnoea syndrome (OSAS) is strongly associated with obesity (OB) and is characterized by several changes in endocrine functions, e.g. GH/IGF-I axis, adrenal and thyroid activity. It is still unclear whether these alterations simply reflect overweight or include peculiar hypoxia-induced hormonal alterations. Hormonal evaluations have been generally performed in basal conditions but we have recently reported that OSAS is characterized by a more severe reduction of the GH releasable pool in comparison to simple obesity. We aimed to extend our evaluation of anterior pituitary function to corticotroph, thyrotroph and lactotroph secretion under dynamic testing in OSAS in comparison with simply obese and normal subjects.

SUBJECTS AND METHODS

In 15 male patients with OSAS [age, mean +/- SEM 43.5 +/- 1.6 years; body mass index (BMI) 39.2 +/- 3.1 kg/m2; apnoea/hypopnoea index, (AHI) 53.4 +/- 8.7], 15 male patients with simple obesity (OB, age 39.7 +/- 1.2 years; BMI 41.2 +/- 2.0 kg/m2; AHI 3.1 +/- 1.2 events/h of sleep) and in 15 normal lean male subjects (NS, age 38.2 +/- 1.4 years; BMI 21.2 +/- 0.8 kg/m2; AHI 1.9 +/- 0.8 events/h of sleep) we evaluated: (a) the ACTH and cortisol responses to CRH [2 microg/kg intravenously (i.v.)] and basal 24 h UFC levels; (b) the TSH and PRL responses to TRH (5 microg/kg iv) as well as FT3 and FT4 levels.

RESULTS

Twenty-four-hour UFC levels in OSAS and OB were similar and within the normal range. Basal ACTH and cortisol levels were similar in all groups. However, the ACTH response to CRH in OSAS (Deltapeak: 30.3 +/- 3.8 pmol/l; DeltaAUC: 682.8 +/- 128.4 pmol*h/l) was markedly higher (P < 0.001) than in OB (Deltapeak: 9.3 +/- 1.4 pmol/l; DeltaAUC 471.5 +/- 97.3 pmol*h/l), which, in turn, was higher (P < 0.05) than in NS (Deltapeak: 3.3 +/- 0.9 pmol/l; DeltaAUC 94.7 +/- 76.7 pmol*h/l). On the other hand, the cortisol response to CRH was not significantly different in the three groups. Basal FT3 and FT4 levels as well as the TSH response to TRH were similar in all groups. Similarly, both basal PRL levels and the PRL response to TRH were similar in the three groups.

CONCLUSIONS

With respect to patients with simple abdominal obesity, obese patients with OSAS show a more remarkable enhancement of the ACTH response to CRH but a preserved TSH and PRL responsiveness to TRH. These findings indicate the existence of a peculiarly exaggerated ACTH hyper-responsiveness to CRH that would reflect hypoxia- and/or sleep-induced alterations of the neural control of corticotroph function; this further alteration is coupled to the previously described, peculiar reduction of somatotroph function.

Concomitant impairment of growth hormone secretion and peripheral sensitivity in obese patients with obstructive sleep apnea syndrome

To clarify the impairment of the GH/IGF-I axis in obstructive sleep apnea syndrome (OSAS), in 13 adult male patients with OSAS (OSA) as well as 15 weight-matched patients with simple obesity (OB) and 10 normal lean male subjects (NS), we studied: 1) the GH response to GHRH (1 micro g/kg iv) plus arginine (30 g iv); and 2) the IGF-I and IGF binding protein-3 responses to a very low dose recombinant human (rh)GH treatment (5.0 microg/kg sc per day for 4 d). The GH response to arginine plus GHRH in OSA was lower than in OB (P < 0.05), which in turn was lower than in NS (P < 0.001). Basal IGF-I levels in OSA were lower than in OB (P < 0.05), which in turn were lower than in NS (P < 0.03). As opposed to OB and NS, in OSA a very low rhGH dose did not affect IGF-I. Adjusting for age and basal values, rhGH-induced IGF-I rise in OSA was lower than in OB (P < 0.01). IGF binding protein-3, glucose, and insulin levels in the three groups were not modified by rhGH. OSA show a more marked impairment of the maximal secretory capacity of somatotroph cells together with reduced IGF-I sensitivity to rhGH stimulation. These findings suggest that OSAS is connoted by a concomitant impairment of GH secretion and sensitivity.

High prevalence of autoimmune phenomena in hepatitis C virus antibody positive patients with lymphoproliferative and connective tissue disorders

The aim of this study was to investigate whether hepatitis C virus (HCV) may perturb the immune system towards autoreactivity. We studied the relationship between the prevalence of anti-HCV and the presence of laboratory and/or clinical autoimmune features in 300 patients: lymphoid malignancies (167) and autoimmune disorders (connective tissue diseases 100; idiopathic thrombocytopenic purpura (ITP) 33). As a control, hepatitis B surface antigen (HBV) and anti-hepatitis B core antigen (anti-HBc) were related to the same parameters. Anti-HCV and anti-HBV were detected in 68/300 (22.6%) and 70/300 (24.6%) patients, respectively. HCV prevalence was 18% in lymphoproliferative disorders (anti-HBc 28.1%) and 26% in connective tissue disease (anti-HBc 16.3%). Among ITP cases, 12/33 (36.4%) were anti-HCV+ and 10/33 (30.3%) anti-HBc+. In 24/30 (80%) anti-HCV+ patients with lymphoproliferative disorders at least one serologic or clinical autoimmune abnormality was detected. To the contrary, only 10/45 (22.2%) anti-HBc+ patients with lymphoproliferative disorders had at least one serologic or clinical abnormality (P < 0.0001). A statistically significant correlation was observed between HCV prevalence and the number of autoimmune alterations in both lymphoproliferative and connective tissue disorders, which was not found for anti-HBc. These data suggest that HCV may skew the immune system toward the production of autoantibodies and also support the possibility that some cases of ITP may be linked to both HCV and HBV infection.