Serum selenium levels and the risk of progression of laryngeal cancer.

BACKGROUND: Observational studies have reported an inverse relationship between selenium status (blood or toenail) and the risk of laryngeal cancer; however, the impact of low serum selenium level on survival has not been evaluated. METHODS: We conducted a prospective study of 296 patients diagnosed with laryngeal cancer in Szczecin, Poland. Serum selenium was measured at diagnosis and prior to treatment. Patients were followed from the date of diagnosis to death at five years. Vital status was obtained by linkage to the Polish National Death Registry. RESULTS: The five-year survival after diagnosis was 82.0% (95% CI: 68% to 91%) for individuals in the highest quartile of serum selenium (> 66.8 µg/L) and was 28.6% (95% CI 19% to 42%) for individuals in the lowest quartile (<50.0 µg/L). In an age- and sex-adjusted analysis, the hazard ratio (HR) for death from all causes was 7.01 (95% CI 3.81 to 12.9) for patients in the lowest quartile of serum selenium, compared to those in the highest quartile. The corresponding multivariate HR was 3.07 (95% CI 1.59 to 5.94). CONCLUSIONS: This study suggests that a selenium level in excess of 70 µg/L is associated with improved outcome among patients undergoing treatment for laryngeal cancer. Further studies are needed to evaluate if selenium supplementation to achieve this level might improve overall prognosis.

A low selenium level is associated with lung and laryngeal cancers.

PURPOSE: It has been suggested that selenium deficiency is a risk factor for several cancer types. We conducted a case-control study in Szczecin, a region of northwestern Poland, on 95 cases of lung cancer, 113 cases of laryngeal cancer and corresponding healthy controls. METHODS: We measured the serum level of selenium and established genotypes for four variants in four selenoprotein genes (GPX1, GPX4, TXNRD2 and SEP15). Selenium levels in the cases were measured after diagnosis but before treatment. We calculated the odds of being diagnosed with lung or laryngeal cancer, conditional on selenium level and genotype. RESULTS: Among lung cancer cases, the mean selenium level was 63.2 µg/l, compared to a mean level of 74.6 µg/l for their matched controls (p<0.0001). Among laryngeal cancer cases, the mean selenium level was 64.8 µg/l, compared to a mean level of 77.1 µg/l for their matched controls (p<0.0001). Compared to a serum selenium value below 60 µg/l, a selenium level above 80 µg/l was associated with an odds ratio of 0.10 (95% CI 0.03 to 0.34; p = 0.0002) for lung cancer and 0.23 (95% CI 0. 09 to 0.56; p = 0.001) for laryngeal cancer. In analysis of four selenoprotein genes we found a modest evidence of association of genetic variant in GPX1 with the risk of lung and laryngeal cancers. CONCLUSION: A selenium level below 60 µg/l is associated with a high risk of both lung and laryngeal cancer.

The effects of diet on selenium concentration in serum in patients with cancer.

The aim of this study was to determine serum levels of selenium (Se) in patients with larynx and urinary system cancers. We also estimated the influence of dietary habits on Se status in examined patients. The mean content of Se in serum of patients with urinary system cancer (48.94 +/- 16.3 mu/l) and larynx cancer (51.00 +/- 18.6 mu/l) was lower than the mean content of Se in the control group (68.25 +/- 15.6 mircog/l; P = 0.000006 or 64.03 +/- 16.8 microg/l; P = 0.0112, respectively). In tissue only, the mean level of Se in patients with kidney cancer (75.37 +/- 40.3 mircog/l) was lower to compare with the dead body control group (220.68 +/- 83.6 microg/l). We have observed the correlation between the content of Se in serum and tissue (r = 0.297; P = 0.002). Patients with studied cancers have deficiency of Se in serum and kidney tissue, and it depends on the diet in about 30%. Frequent consumption of eggs, ham, and wine has the biggest influence on the content of Se in serum of patients in Poland, whereas frequent consumption of pulses, eggs, bacon, and lard is connected with the content of Se in tissue.

HPV-induced recurrent laryngeal papillomatosis: dietary fatty acid and micronutrient intakes.

Human papilloma virus (HPV)-induced recurrent laryngeal papillomatosis (RLP) is a chronic debilitating disease often encountered among children of poor socio-economic South African groups. There are a few studies and limited evidence as to what extent nutrition may contribute to this disease. To our knowledge this is the first study that gives an account of dietary FA and micronutrient intakes in RLP patients, according to food frequency questionnaires. The dietary FA profile revealed an excessive linoleic acid (LA) intake syndrome and is also marked by high palmitic acid (PA), oleic acid (OA) and SFA intakes. Research revealed that enhanced LA and PA drive, respectively, mitogenic stimuli and apoptotic resistance during tumorigenesis, whist SFAs are associated with lipid rafts, the Th1 immune response and immunosuppression. Low folate intake, a risk for HPV-infection, and low Zn intake, detrimental for lipid metabolism and immunocompetence, occurred in, respectively, 70% and 20% RLP patients. The poor correlations that were found in RLP patients between essential fatty acids (EFAs) and micronutrients, namely, Mg, Zn and Se, involved in lipid metabolism and immune responses, need proper clarification. Overall, it is plausible that the diet (poor nutrition), a shift in lipid metabolism caused by HPV- infection, environmental smoke and oxidative stress, as well as extra-esophageal acid reflux with secondary inflammation in the larynx are co-factors in the etiology of laryngeal papillomatosis, and that immunocompromised patients are subjected to recurrence. It is imperative to ensure that children with RLP receive proper nutrition and follow a healthy lifestyle to prevent disease recurrence after treatment.

Photodynamic therapy using m-tetra(hydroxyphenyl) chlorin. An animal model.

OBJECTIVE: To evaluate the potent photosensitizer m-tetra (hydroxyphenyl) chlorin (m-THPC) by using rabbits with cottontail rabbit papillomavirus-induced tumors and the canine larynx as model systems. DESIGN: Nonrandomized control trial. SETTING: Division of ear, nose, and throat research at a tertiary care teaching hospital. MATERIALS: Rabbits were used for relative retention ratio studies and tissue tolerance tests. Studies on the swelling of normal tissues in the larynx after photoactivation were done with canines. INTERVENTION: Animals were injected with 0.3 mg/kg of m-THPC. At varying intervals, tissues were exposed to 652 nm of light. OUTCOME MEASURES: Outcome measures consisted of four elements: (1) decay of plasma concentration over time, (2) interval to and duration of maximal ratio between drug concentration in normal tissue and tumor, (3) maximal permissible light exposure to normal tissue (skin and laryngeal mucosa) at an optimal interval, and (4) efficacy--number of tumors with partial and complete response. RESULTS: The largest papilloma to skin ratio (10:1) occurred 4 to 8 days after drug injection. The rabbit skin damage threshold was 40 to 60 J/cm2 at 6 days. The canine laryngeal edema and erythema thresholds were 50 to 70 J. A 75% cure rate of papillomas was achieved with tumors that were less than 100 mm2 in area at light doses that ranged from 25 to 75 J/cm2. CONCLUSIONS: m-THPC shows efficacy in treating papilloma virus-induced tumors. We present a protocol for rapid optimization of the factors required for tumor destruction with minimal normal tissue damage, thus permitting determination of an optimal therapeutic protocol for any photosensitizer.

[The function of the oxidant-antioxidant system in patients with laryngeal cancer]. / Sostoianie oksidantno-antioksidantnoi sistemy u bol'nykh rakom gortani.

Lipid peroxidation and antioxidant system were studied at hospital admission, on postoperative day 1, 3 weeks and half a year after surgery in 86 patients with different stages of laryngeal cancer. A correlation is stated between lipid peroxidation disturbances and the defects in the protective antioxidant system. Low-frequency laser irradiation of autoblood produced a clinically beneficial effect and stabilized biochemically the relations between lipid peroxidation and antioxidant systems.

Laryngeal cancer and blood selenium levels.

Blood selenium concentrations in 43 patients with laryngeal cancer and 47 normal subjects were determined by atomic absorption spectrophotometry. No significant differences in selenium values were observed in sera from the cancer patients when compared with controls, but there were significant differences between patients with advanced (T4) supraglottic cancers and the normal controls. These results suggest that lower blood selenium levels in this latter group of laryngeal cancer patients may be a consequence of their disease rather than its cause.

[The hematopoietic characteristics of laryngeal cancer patients undergoing thermoradiosensitization]. / Osobennosti krovetvoreniia u bol'nykh rakom gortani v usloviiakh termoradiosensibilizatsii.

Peripheral blood and bone marrow were studied in 46 patients suffering laryngeal cancer. Two schedules of radiotherapy with and without local hyperthermia were used. Complex hematologic study included electron microscopy of the bone marrow. Apart from general hematologic parameters, partial erythro- and granulocytograms of the bone marrow, mitotic index of karyocytes and morphologic anomalies of erythrokaryocytes were studied. Hematologic studies were conducted both before and after a course of radiotherapy. Adverse effect of hyperthermia and radiation therapy on cells of the granulocytic and immunologic component of hemopoiesis was established.