Selenium substitution during radiotherapy of solid tumours - laboratory data from two observation studies in gynaecological and head and neck cancer patients.

OBJECTIVE: Selenium is an essential cofactor of the enzyme glutathione peroxidase (GSH-Px), which is important for the endogenous detoxification of free radicals. A reduced activity of GSH-Px is related to increased toxicities due to radiation therapy during primary cancer treatment. Therefore, selenium substitution may be a new supportive strategy to diminish radiation-associated side effects. PATIENTS AND METHODS: The selenium blood concentrations of 121 radiotherapy patients were measured in two randomized observation studies (81 gynaecological tumours, 40 head and neck tumours). Measurements (atom absorption spectrometry) were performed on serum and whole blood (WB) samples before, in the middle of, at the end, and 6 weeks after radiotherapy. In cases of decreased selenium levels in WB, 63 patients (mean age 63.83+/-9.23 a) received selenium substitution (500 microg sodium selenite at RT days, 300 microg at the weekend) and 64 patients (mean age 63.03+/-10.47 years) were evaluated as control group without any selenium substitution. Both groups were well balanced according to tumour localization and stage. Reference values were 85-162 microg/l WB-selenium, and 65-135 microg/l serum-selenium. RESULTS: We measured the following WB selenium (Se) levels (Se-group vs. control group, U-test): begin RT 64.17+/-13.98 microg/l vs. 64.50+/-14.47 microg/l (p=0.869); mid RT 92.48+/-26.68 microg/l vs. 65.80+/-18.04 microg/l (p<0.001); end RT 93.78+/-25.90 microg/l vs. 64.06+/-17.54 microg/l (p<0.001); 6 weeks after RT 74.01+/-20.06 microg/l vs. 69.66+/-17.83 microg/l (p=0.183). The serum levels were as follows: begin RT 59.18+/-13.49 microg/l vs. 61.99+/-15.72 microg/l (p=0.427); mid RT 104.75+/-31.41 microg/l vs. 62.37+/-16.23 microg/l (p<0.001); end RT 100.63+/-31.12 microg/l vs. 62.29+/-16.11 microg/l (p<0.001); 6 weeks after RT 72.73+/-26.53 microg/l vs. 64.17+/-17.22 microg/l (p=0.170). CONCLUSION: The used dosage of 500 microg sodium selenite per day is sufficient to treat selenium deficiency during radiotherapy. After substitution, the patient returns to their individual selenium status.

Zinc concentrations in serum during head and neck cancer progression.

UNLABELLED: Reduced serum-zinc concentrations are well known as typical laboratory characteristics in advanced head and neck cancer. Our aim was to follow the development of this phenomenon during the disease. PATIENTS AND METHODS: A total of 21 patients were included in this pilot-study (1 female, 20 male). The median age was 64 years, range 43-80 years. The following tumour localizations were registered: 11 larynx, 4 oropharynx, 2 hypopharynx and 4 other. Serum zinc levels were registered at baseline and during the follow-up investigations using flame atomic absorption spectrometry. RESULTS: The median follow-up time was 17 months, range 6-43 months. During the follow-up, 9/21 patients died tumour-dependently, 2 patients were living with cancer, 8 patients showed NED, and a further 2 patients died of non-cancer related causes. The zinc concentration decreased from 0.76 mmol/l (0.48-1.07 mmol/l) to 0.55 mmol/l (0.32-1.01 mmol/l). Nine of 11 patients with cancer developed extremely low serum zinc concentration 4-6 weeks before dying. CONCLUSION: The serum zinc concentration may be a marker for definitive palliative situations in head and neck cancer patients.

Serum selenium in head and neck cancer patients--a new marker of tumor activity?

OBJECTIVE: The purpose of this work was to investigate the relationship between the tumor volume and the endogenous selenium levels in untreated head and neck cancer patients. MATERIALS AND METHODS: One hundred consecutive patients were included in this study. We measured the endogenous levels of selenium in the serum and the whole blood of all patients by atomic absorption spectrometry. Additionally, the activity of glutathione peroxidase and the concentration of malonedialdehyde were observed. The resectability of the tumor was used as an independent marker of the tumor volume. RESULTS: Thirty-one out of 100 patients had resectable tumors, while 69 patients were characterized as unresectable. The following median results were obtained (resectable versus unresectable): Serum Se 0.90 micromol/l versus 0.78 micromol/l (p=0.024); whole blood Se 1.00 micromol/l versus 0.93 micromol/l (p=0.139); glutathione peroxidase 145 U/l versus 148 U/l (p=0.93); and malonedialdehyde 2.21 mmol/l versus 2.6 mmol/l (p=0.84). CONCLUSION: The concentration of serum selenium shows a significant relationship with tumor resectability in patients with advanced head and neck cancer.

Low-dose radiotherapy for painful heel spur. Retrospective study of 117 patients.

PURPOSE: Retrospective analysis of 117 patients treated between 1996 and 2000 with low-dose radiotherapy (RT) for painful heel spurs. PATIENTS AND METHODS: 71 women and 46 men were irradiated on 136 painful heel spurs in one (n = 104) or two radiation series (n = 13). The painful spurs were located either at the plantar (n = 94), dorsal (n = 5) or bilateral heel (n = 18). 82 patients had prior treatments, in 35 patients RT was the primary treatment. Low-dose RT was performed twice a week with one 6-MV photon field. Ten fractions of 0.5 Gy were applied to a total dose of 5 Gy. Evaluation was done on completion and during follow-up using the four-scale von Pannewitz score. RESULTS: On completion of RT, 27 patients were free of pain, 40 were much improved, 31 reported slight improvement, and 19 experienced no change. After a mean follow-up of 20 months, 75 out of 100 patients were free of pain, twelve had marked and three some improvement. Ten patients reported no change of symptoms. Mean duration of pain before RT was 6 months. RT applied < or = 6 months after the onset of clinical symptoms resulted in improvement in 94%. By contrast, an interval of > 6 months until the initiation of RT resulted in only 73% of patients with clinical improvement. CONCLUSION: Low-dose RT reveals a benefit in > 80% of the patients. RT should start during the first 6 months of symptoms. Prospective clinical studies with validated symptom scores should be conducted to assess optimal dose and fractionation scheme of RT.

Selenium in the treatment of radiation-associated secondary lymphedema.

PURPOSE: The aim of this explorative study was to evaluate the impact of selenium in the treatment of lymphedema after radiotherapy. MATERIALS AND METHODS: Between June 1996 and June 2001, 12 patients with edema of the arm and 36 patients with edema of the head-and-neck region were treated with selenium for therapy-related lymphedema. Of these 36 patients, 20 had interstitial endolaryngeal edema associated with stridor and dyspnea. All patients received sodium selenite over 4 to 6 weeks. RESULTS: Self-assessment using a visual analog scale (n = 48) showed a reduction of 4.3 points when comparing pre- and posttreatment values (p < 0.05). Of 20 patients with endolaryngeal edema, 13 underwent no tracheostomy, 5 underwent a temporary tracheostomy, and only 2 underwent a permanent tracheostomy. Ten of 12 patients with arm edema showed a circumference reduction of the edematous limb and improvement in the Skin-Fold Index by 23.3 points. An improvement of one stage or more was shown by the Földi or the Miller score (n = 28) in 22 (Földi score) and in 24 (Miller score) patients. CONCLUSIONS: Treatment with sodium selenite is well tolerated and easy to deliver. Additionally, our results suggest that sodium selenite has a positive effect on secondary-developing lymphedema caused by radiation therapy alone or by irradiation after surgery.

Combined radiotherapy and temozolomide in patients with recurrent high grade glioma.

AIMS AND BACKGROUND: There is only little preliminary information about combined-modality treatment with radiotherapy and temozolamide. The purpose of this analysis was to document the feasibility of such combined-modality treatment. METHODS: We treated 25 patients with recurrent high grade gliomas after standard therapy (surgery and radiation) with the following schedule: 400 mg temozolomide orally for five days repeated every 28 days, and radiotherapy at a dose of 20-30 Gy (2 x 1.2 Gy per day). Four of these patients underwent a second operation without complete tumor resection. RESULTS: After 125 courses of temozolomide, grade 1 (NCI-CTC) thrombocytopenia was found in four patients and grade 2 in two patients. Two patients developed grade 1 leukocytopenia and two others grade 2. CTC grade 1-2 nausea was observed in eight patients. For one patient we reduced the dose of temozolomide to 300 mg/day because of thrombocytopenia. One patient discontinued therapy after the first course because of leukocytopenia and nausea. CTC grade 3-4 side effects did not occur. Combined-modality treatment showed no more side effects than treatment with temozolomide alone. The median duration of response was seven months. CONCLUSION: The observed side effects were tolerable. Combined treatment with radiotherapy and temozolomide is feasible. Further investigation of this agent is necessary.