Bayesian and regularization methods for hyperparameter estimation in image restoration

In this paper, we propose the application of the hierarchical Bayesian paradigm to the image restoration problem. We derive expressions for the iterative evaluation of the two hyperparameters applying the evidence and maximum a posteriori (MAP) analysis within the hierarchical Bayesian paradigm. We show analytically that the analysis provided by the evidence approach is more realistic and appropriate than the MAP approach for the image restoration problem. We furthermore study the relationship between the evidence and an iterative approach resulting from the set theoretic regularization approach for estimating the two hyperparameters, or their ratio, defined as the regularization parameter. Finally the proposed algorithms are tested experimentally.

Infection of sand flies by humans coinfected with Leishmania infantum and human immunodeficiency virus

To determine the role that Leishmania infantum/human immunodeficiency virus (HIV) coinfected patients could play in the epidemiology of visceral leishmaniasis (VL), we applied direct xenodiagnosis of VL in this study to test the infectivity of six coinfected patients to colonized Phlebotomus perniciosus. All patients proved to be infective for the sand flies. The infectivity of patients who had still not received specific treatment for VL was inversely proportional to their absolute CD4+ T lymphocyte cell count. It has been proven that P. perniciosus can acquire and allow the development of L. infantum by feeding on L. infantum/HIV coinfected patients. Since this sand fly is an important vector of VL in southern Europe, a new natural anthroponotic cycle could be considered in the epidemiology of L. infantum/HIV coinfection. The design of leishmaniasis control programs and the management of coinfected individuals should take these findings into account.

Impaired production of interleukin 6 and tumour necrosis factor alpha in whole blood cell cultures of patients with multiple myeloma

Cytokine production in whole blood cell cultures can be an indicator of immune cellular status in neoplastic patients. Production of interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-alpha) after stimulation with lipopolysaccharide was measured in 1/10 diluted whole blood culture of patients with monoclonal gammopathies [monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM)]. With this system, lower production of IL-6 and TNF-alpha at 4, 24 and 48 h in total blood cultures in patients with symptomatic MM was observed. Thus, the capacity of cytokine production was greater in control subjects and in patients with MGUS and MM in response than in symptomatic MM (P=0.005 at 4 h and P=0. 006 at 24 and 48 h for IL-6 and P<0.0001 at 24 h and P<0.001 at 48 h for TNF-alpha). These differences remained significant after adjustment on the basis of the lymphocyte count (P<0.001 for IL-6 and TNF-alpha at 24 and 48 h). The impaired IL-6 and TNF-alpha production in patients with symptomatic MM is probably due to a tumour-related immunosuppressive status.

Adenoid cystic carcinoma of the breast: mammographic appearance and pathologic correlation

OBJECTIVE

The objective of our study was to describe the mammographic features of adenoid cystic carcinoma of the breast and to correlate mammography findings with histopathologic findings.

CONCLUSION

Adenoid cystic carcinoma is a rare type of breast neoplasm that usually appears as a slowly enlarging nodule. In spite of its low incidence, recognition is important because early detection ensures good prognosis. On mammography, these tumors often appear as moderately circumscribed, lobulated nodules that are similar to other types of benign and malignant tumors. Therefore, cytologic and histologic evaluations are needed for accurate diagnosis.

Analytical and clinical evaluation of an electrochemiluminescence immunoassay for the determination of CA 125

The CA 125 II assay on the Elecsys(R) 2010 analyzer was evaluated in an international multicenter trial. Imprecision studies yielded within-run CVs of 0.8-3.3% and between-day CVs of 2.4-10.9%; CVs for total imprecision in the manufacturer's laboratory were 2.4-7.8%. The linear range of the assay extended to at least 4500 kilounits/L (three decades). Interference from triglycerides (10.3 mmol/L), bilirubin (850 micromol/L), hemoglobin (1.1 mmol/L), anticoagulants (plasma), and several widely used drugs was undetectable. Method comparisons with five other CA 125 II assays showed good correlation but differences in standardization. A 95th percentile cutoff value of 35 kilounits/L was calculated from values measured in 593 apparently healthy (pre- and postmenopausal) women. In 95% of patients with benign gynecological diseases CA 125 was </=190 kilounits/L; 63% of patients with newly diagnosed ovarian carcinoma had values >190 kilounits/L. A comparison of CA 125 values obtained with the Elecsys test and with other common CA 125 tests in monitored patients being treated for ovarian cancer showed identical patterns. In conclusion, the Elecsys CA 125 II assay is linear over a broad range, yields precise and accurate results, is free from interferences, and compares well with other assays.

[Cholera in a district of Peru]

Taking to consideration the low report of cholera patients and with the main knowing the reality about the introduction of Vibrio cholerae (V. cholerae) in Peru, a sample of 101 cases with acute diarrheal disease (ADD) was taken at the Distrito Villa El Salvador. They were selected by a systematic randomized sampling defined for each health care unit in the District, according to the daily average occurrence of ADD cases attended a week before the beginning of the study. All of them took part in a epidemiological survey. A sample was taken by rectal swab in order to isolate V. cholerae. 53 positive cases were found (52.2% and a confidence interval from 42.29 to 62.5%) with significant differences (p < 0.01) between the frequency in adults (67.3%) and children (34.8%). V. cholerae was isolated only in 13 (61.9%) of the 21 cases who had contact with cholera patients, for a relative risk of 1.24 (0.83 < RR < 1.85). A high positivity was also found, 21 cases (72.4%) among those who had raw food. A significant difference (p < 0.01) was observed in connection with those who had cooked food. In the multivariate logistic regression analysis it was only found a significant relationship with age and with the ingestion of raw food as regards the occurrence of cholera.

Limitations in the use of glutathione S-transferase P1 in urine as a marker for bladder cancer

BACKGROUND

GST pi (GSTPl) is overexpressed in bladder cancer and desquamation of the tumour may produce detectable levels of urinary GSTPl which could be used as a marker for the early diagnosis of bladder cancer.

MATERIALS AND METHODS

A preliminary study in 27 transitional cell carcinoma (TCC) patients and 20 controls, using an ELISA methodl is presented here.

RESULTS

55.5% of TCC patients were positive for GSTP1, while all control samples were negative. Some of the GSTP1 positive cases also gave positive results for haematuria, which indicates that a limitation of this marker involves the contamination of the urine with erythocyte GSTP1. In 5 cases (18.5%) without haematuria detectable levels of GST pi were found.

CONCLUSIONS

Further studies would be required to assess the advantages of this technique over clas sical cytology or as a complement to it, especially in patients in a phase of temporary negative haematuria.

c-erbB-2 oncoprotein, CEA, and CA 15.3 in patients with breast cancer: prognostic value

The diagnostic value of a new tumor marker, c-erbB-2, was studied in the sera of 50 healthy subjects, 58 patients with benign breast diseases, and 413 patients with breast cancer (186 locoregional, 185 with advanced disease, and 42 with no evidence of disease). Using 15 U/ml as the cut-off, no healthy subjects or patients with benign diseases and only 2.4% of no evidence of disease patients had elevated serum levels. Abnormal c-erbB-2 levels were found in 29% (101/370) of the patients with breast carcinoma (locoregional 9%, metastases 45.4%). CEA (cut-off 5 U/ml) and CA 15.3 (cut-off 35 U/ml) sensitivity was 18% and 16% in patients with locoregional disease and 61% and 70% in those patients with advanced disease, respectively. A trend toward higher serum levels of all three tumor markers in patients with nodal involvement or greater tumor size was found, but was statistically significant only with CEA (p < 0.01). By contrast, c-erbB-2 was related to steroid receptors, in both locoregional and metastatic tumors. When the prognostic value of these markers was evaluated, patients with abnormally high presurgical CEA and c-erbB-2 had a worse prognosis than those patients with normal values, in both node-negative (p < 0.05 and p < 0.001, respectively) and node-positive patients (p < 0.556 and p < 0.001, respectively). By contrast, no relationship was found between CA 15.3 values and prognosis. Multivariate analysis showed that CEA and c-erbB-2 were also prognostic factors. The correlation between serum and tissue levels of c-erbB-2 was studied in the tumors of 161 patients. Significantly higher c-erbB-2 serum levels were found in patients with overexpression in tissue by immunohistochemistry, in both locoregional and advanced disease (p = 0.0001). Serum concentrations in patients with advanced disease were related to the site of recurrence, with significantly higher values in patients with metastases (mainly in those with liver metastases) than in those with locoregional recurrence. In summary, c-erbB-2 serum levels seem to be a useful tumor marker in the prognosis of patients with breast cancer. Using all three tumor markers, sensitivity was 35% in patients with locoregional breast cancer and 88% in patients with recurrence.

Synergistic sedation with propofol and midazolam in intensive care patients after coronary artery bypass grafting

OBJECTIVES

To evaluate and compare the clinical efficacy, impact on hemodynamics, safety profiles, and cost of combined administration of propofol and midazolam (synergistic sedation) vs. midazolam and propofol administered as sole agents, for sedation of mechanically ventilated patients after coronary artery bypass grafting.

DESIGN

Prospective, controlled, randomized, double-blind clinical trial.

SETTING

Intensive care unit of SCIAS-Hospital de Barcelona.

PATIENTS

Seventy-five mechanically ventilated patients who underwent coronary artery bypass graft surgery under low-dose opioid anesthesia.

INTERVENTIONS

According to the double-blind method, patients were randomly assigned to receive propofol (n = 25), midazolam (n = 25), or propofol combined with midazolam (n = 25). Infusion rates were adjusted to stay between 8 and 11 points on Glasgow Coma Score modified by Cook and Palma.

MEASUREMENTS AND MAIN RESULTS

Mean +/- SD duration of sedation was 14.4 +/- 1.5 hrs, 14.1 +/- 1.1 hrs, and 14.7 +/- 1.9 hrs for the propofol, midazolam, and synergistic groups, respectively. The induction dose was 0.55 +/- 0.05 mg/kg for propofol as sole agent, 0.05 +/- 0.01 mg/kg for midazolam as sole agent, and 0.22 +/- 0.03 mg/kg for propofol administered in combination with 0.02 +/- 0.00 mg/kg of midazolam (p = .001). The maintenance dose was 1.20 +/- 0.03 mg/kg/hr for propofol as sole agent, 0.08 +/- 0.01 mg/kg/hr for midazolam as sole agent, and 0.50 +/- 0.09 mg/kg/hr for propofol administered in combination with 0.03 +/- 0.01 mg/kg/hr of midazolam (p < .001). All sedative regimens achieved similar efficacy in percentage of hours of adequate sedation (93% for propofol, 88% for midazolam, and 90% for the synergistic group, respectively). After induction, both propofol and midazolam groups had significant decreases in systolic blood pressure, diastolic blood pressure, left atrial pressure, and heart rate. Patients in the synergistic group had significant bradycardia throughout the study, without impairment in other hemodynamic parameters. Patients sedated with propofol or synergistic regimen awoke sooner and could be extubated before those patients sedated with midazolam (0.9 +/- 0.3 hrs and 1.2 +/- 0.6 hrs vs. 2.3 +/- 0.8 hrs, respectively, p = .01). Synergistic sedation produced cost savings of 28% with respect to midazolam and 68% with respect to propofol.

CONCLUSIONS

In the study conditions, the new synergistic treatment with propofol and midazolam administered together is an effective and safe alternative for sedation, with some advantages over the conventional regimen with propofol or midazolam administered as sole agents, such as absence of hemodynamic impairment, >68% reduction in maintenance dose, and lower pharmaceutical cost.

[Content of carbohydrates and trace elements in a group of non-alcoholic drinks]

BACKGROUND

In order to elaborate recommendations for the dietetic care of diabetic patients and other clinical disorders we have measured the concentration of carbohydrates and trace elements in a group of non alcoholic refreshments of current use in Spain.

MATERIAL AND METHODS

Thirty refreshments were classified into 10 groups. Glucose and phosphate were measured by hexokinase and reduction of phospho-molybdate methods respectively in an autoanalyzer Dax-72. Glucose and fructose were analyzed by cellulose thin-layer chromatography; glucose, fructose and sucrose by gas chromatographys. Sodium and potassium by emission spectrophotometry and calcium, magnesium, iron, copper and zinc by atomic absorption spectrophotometry.

RESULTS

Light refreshments and soft drinks have no carbohydrates. Isotonic beverages, fruit juices, cool tea and non alcoholic beers had less than 10 g/dl. Tonic waters, Fanta, different coles, non alcoholic bitter and others had more than 10 g/dl. Sodium levels between 15-20 mEq/l were found in the isotonic beverages and 7-Up and levels of 7 mEq/l in the others. Potassium values between 15-40 mEq/l were found in the fruit juices, 3-4 mEq/l in Gatorade and less than 1 mEq/l in the others.

CONCLUSIONS

Light refreshments and soft drinks contain low concentrations of carbohydrates and sodium. Fruit juices have high potassium concentration. Such information can be especially useful for dietetic care of diabetic patients.

Lack of correlation between tumor markers (CA 125 and SCC) and systemic lupus erythematosus activity

BACKGROUND

Recently, tumor markers (CA 125 and SCC) have been suggested as possible activity markers of systemic lupus erythematosus (SLE), but study results have been contradictory.

OBJECTIVE

The aim of this study was to evaluate the possible relationship between CA 125 and SCC serum levels and SLE activity.

PATIENTS AND METHODS

Serum levels of CA 125 from 59 patients and levels of SCC from 53 patients with SLE were analyzed. Both tumor markers were determined by ELISA, considering 35 U/ml (CA 125) and 2.5 ng/ml (SCC) respectively as the upper limit of normality. The serum levels of these tumor markers were correlated with the SLE disease activity index (SLEDAI).

RESULTS

The CA 125 concentrations in active SLE (mean 13.8 + 15.3) were similar to those in inactive patients (mean 13.1 + 11.7 U/ml). Significantly high CA 125 serum levels were found only in SLE patients with nephrotic syndrome (p = 0.001). No significant differences were found in SCC serum levels in SLE patients with (mean 0.9 +/- 0.8 ng/ml) or without activity (mean 1.1 +/- 1.3 ng/ml). Likewise, no relationship between SCC serum levels and parameters related to SLE activity were found, excluding slight increases associated with renal failure.

CONCLUSIONS

The correlation that some authors have found between elevated serum levels of CA 125 and SLE activity is only associated with the presence of nephrotic syndrome. Likewise, SCC is not related with SLE activity and the increases found may be due to renal failure.

[Ameloblastic fibro-odontoma. Clinical aspects and review of the literature]

Ameloblastic fibro-odontoma is a rare odontogenic tumor. It is formed by proliferation of epithelial odontogenic elements combined with ectomesechimal tissue. The presence of dentine, enamel and osteoid like tissue can be identified. Cases of sarcomatous degeneration have been described. In this work, we present two new cases of ameloblastic fibro-odontoma, analyzing the most important aspects of their differential diagnosis, with a review of literature.

Tumor markers in response monitoring and prognosis of non-small cell lung cancer: preliminary report

BACKGROUND

The significance of tumor markers in lung cancer is not well established.

PATIENTS AND METHODS

We analyzed level of serum markers as prognostic factor of response and survival in 46 evaluable patients with locally advanced or metastasic non small cell lung cancer. All patients were treated with cisplatin 120 mg/m2 or carboplatin 400 mg/m2 day 1, plus etoposide 80 mg/m2 days 1 to 3.

RESULTS

Partial response was obtained in 11 patients (24%), stabilization in 18 and progression in 17. Tumor marker sensitivities were: CEA 37%, CA 125 54.5%, SCC 17.5%, NSE 30.5%, and CYFRA 52%. Higher levels of CEA and NSE correlated with more probability of response (p < 0.001 and p = 0.002). The survival probability of patients with normal pretreatment levels of NSE was significantly better than those with NSE over normal level (15.2 vs 7.2 months) p = 0.02. In patients who achieved partial response, CEA, CA 125 and CYFRA levels decreased significantly with respect to the pretreatment values.

CONCLUSIONS

Patients with high CEA and NSE serum level have an increased probability of response than patients with low initial levels; however, patients with high initial level of NSE have poor survival. The decrease in CEA, CA 125 and CYFRA values at the moment of response evaluation could help in response assessment.

Zero incidence of inhibitor development in previously treated haemophilia A, HIV-negative patients upon exposure to a plasma-derived high-purity and double viral inactivated factor VIII concentrate

Thirty-six haemophilia A, HIV-negative, previously treated patients were changed therapy to a highpurity and double-inactivated (solvent/detergent and dry-heating) previously unused factor VIII concentrate. The mean age of these patients was 27 years at the time of the change. Twenty-three patients were severe haemophiliacs (FVIII:C < 0.02 IU mL-1), seven moderate (FVIII:C between 0.02 and 0.05 IU mL-1) and six mild (FVIII:C > 0.05 IU mL-1). The mean follow-up with this single product was 16 months, with 82 accumulated exposure days and the mean consumption was 117,300 IU of FVIII corresponding to a mean of six batches per patient. No patient developed FVIII inhibitors (upper limit of the CI95: 7.98%), resulting in an incidence rate of 0/48 patient-years (upper limit of the CI95: 77/1000 patient-years). The change in therapy to this new factor VIII concentrate was not associated with the appearance of inhibitors.

Glutathione and glutathione S-transferases in human squamous cell carcinomas of the larynx and GSTM1 dependent risk

BACKGROUND

The aim of the present study was to establish the risk of squamous cell carcinoma (SCC) of the larynx associated with the congenital absence of glutathione S-transferase M1 (GSTM1), and to describe the expression of the isoenzymes GSTA1/2, GSTP1-1, and GSTM1 and glutathione (GSH) content in healthy and tumoral larynx tissue.

MATERIAL AND METHODS

Blood samples from 160 SCC male patients and 158 controls were phenotyped for GSTM1 by ELISA. Using 37 paired samples (normal and tumour specimens) from cancer patients we carried out a descriptive study of enzyme activity by ELISA (GSTs) and Ellman's as say (GSH) RESULTS: GSTM1 null phenotype was more common in the SCC group than in controls (OR 1.9, CIs 1.18-3.05, p = 0.004). Total GST activity was higher in tumour samples than in matched healthy tissue (2.2-fold, p-0.00001), being largely determined by GSTP1-1 (1.9-fold increased in malignant tissue; p = 0.0003). The GSH content was also significantly higher in SCC than in normal mucosa (1.9-fold, p = 0.0007).

CONCLUSIONS

We confirmed the GSTM1-dependent risk for larynx cancer among smokers. The overexpression of the GST/GSH system in tumours reported here indicates their possible role in chemoresistance to pharmacological therapy.

p53 oncoprotein as a prognostic indicator in patients with breast cancer

p53 is a tumor suppressor gene located on the human chromosome 17 that is thought to regulate (suppress) the proliferation of normal cells. The mutant protein accumulates in the nuclei of tumor cells that may then have a proliferative advantage over normal cells. The purpose of this study was to investigate the relationship between levels of mutant p53 expression and the clinical outcome of patients with node-positive and node-negative breast cancer. Expression of mutant p53 was evaluated in 655 human breast carcinomas (349 node-positive and 306 node-negative patients) with long-term clinical follow-up by immunohistochemistry in sections from paraffin embedded tumors.

RESULTS

Immunoreactivity was found in 37.3% of breast tumors. There was no significant correlation between the expression of p53 and tumor size, nodal involvement, age or histological type. However, p53 overexpression was clearly related to histological grade and steroid receptors, with a trend to higher overexpression in ER-tumors or in those with a high histological grade (p < 0.01). On univariate analysis positive tumors were associated with reduced DFS in the total group (p < 0.001) as well as in node-positive patients (p < 0.05) and in node-negative patients (p < 0.01). In conclusion, these results suggest that the immunoreactivity of p53 may be a biologic marker of prognostic significance in both node-positive and node-negative patients.

Free and total PSA in the diagnosis of prostate cancer

The use of PSA in the diagnosis of prostate cancer is controversial. This is due to false-positive results caused by benign prostatic hyperplasia (BPH). Different forms of circulating PSA have recently been described. Initial studies indicate that the fraction of free PSA is lower in prostate cancer than in BPH, therefore suggesting that its measurement could be of some diagnostic value. We have assessed the serum value of the percentage of free/total PSA in the differential diagnosis of BPH and prostate cancer. The levels of PSA and free PSA (DELFIA) were measured in 145 BPH patients and 56 prostate cancer patients. Free PSA is a small fraction of PSA, and significantly lower levels are being found in prostate cancer. In those patients with a PSA level between 2 and 25 micrograms/l, the determination of the percentage of free PSA increased the diagnostic efficiency of PSA, while reducing the number of negative biopsies. We conclude that free PSA may be a useful marker for the diagnosis of prostate cancer.

Social, familial and medical aspects of Usher syndrome in Colombia

A psycho-social study was performed in 19 Colombian families with 40 affected individuals with Usher syndrome, identified through our national screening program for this disease in Colombia. The study was aimed to understand their needs, kind of familial inter-relationships, and social and familial implications of the patients' double sensorial limitation, in order to provide enough information to support the importance of early diagnosis, appropriate genetic counseling, and the establishment of adequate educational and rehabilitation programs in Colombia.

Efficacy and safety of two new methods of rapid intravenous detoxification in heroin addicts previously treated without success

BACKGROUND

New methods of rapid opiate detoxification, under intravenous sedation, can detoxify heroin-addicted patients in 24 hours. Their clinical application has been limited by the lack of studies establishing both efficacy and safety.

METHOD

In a randomised, controlled study, 300 treatment-refractory, heroin-addicted patients received rapid intravenous detoxification treatment (naloxone infusion, 0.06-0.08 mg/kg, then oral naltrexone 50 mg/day) under either monitored light intravenous sedation or unmonitored deep intravenous sedation.

RESULTS

All patients were successfully detoxified and 93% remained abstinent one month later. Severity of withdrawal, according to the Wang Scale modified by Loimer, was 4.9 (s.d. 3.0) points in the light sedation group and 4.8 (s.d. 2.9) in the deep sedation group (P = 0.26). Two patients (1.3%) in the light sedation group and four (2.6%) in the deep sedation group required tracheal intubation (P = 0.31). There was only one severe complication, a case of nosocomial aspirative pneumonia which improved with antibiotic treatment.

CONCLUSIONS

Successful rapid intravenous detoxification can be achieved using relatively light levels of sedation.

Anti-Sia-lb (anti-Gd) cold agglutinins bind the domain NeuNAc alpha2-3Gal in sialyl Lewis(x), sialyl Lewis(a), and related carbohydrates on nucleated cells and in soluble cancer-associated mucins

Anti-Sia-lb (formerly anti-Gd) cold agglutinins (CAs) recognize sialylated carbohydrates on both adult and neonate red blood cells (RBCs). RBC CA activity inhibition experiments reported here indicate that the domain NeuNAc alpha2-3Gal, as found in sialyllactose, synthetic sialyl(s) Lewis(Le)(x) and sLe(a), sialyllactosamine, sialyl-fucosyllactose, and nonfucosylated sLe(a), constitutes the minimal epitope for these CAs, implicating that these autoantibodies could be able to bind this domain in sLe(x) and sLe(a) and related carbohydrates expressed on nucleated cells and in soluble cancer-related mucins. The following data obtained with the previously characterized monoclonal IgMk anti-Sia-lb CA, GAS, show that this is the case. GAS epitope expression among leukocytes that lack sLe(a) parallels that of sLe(x) determinant as detected by mouse monoclonal antibodies (MoAbs), especially MoAb KM-93. It is also found on epithelial malignant cells bearing both sLe(x) and sLe(a). GAS epitope on these nucleated cells, (1) like that present on RBC, is abolished by sialidase, unaffected by proteases, and inhibited by sialyllactose; and (2) is overlapping and/or proximal to that recognized by anti-sLe(x) MoAb, CSLEX-1, and KM-93. Moreover, CAGAS binds soluble cancer-associated mucins bearing sLe(x) and sLe(a) determinants. This binding is inhibited by sialyllactose and these mucins inhibit the RBC CA activity of CAGAS. The possible significance of anti-Sia-lb (anti-Gd) CAs as autoantibodies directed to carbohydrate ligands of host adhesion molecules that might be receptors of microbial adhesins of some CA-inducing pathogens is discussed.

Phase III placebo-controlled trial of capsaicin cream in the management of surgical neuropathic pain in cancer patients

PURPOSE

A minority of cancer survivors develops long-term postsurgical neuropathic pain. Based on evidence that capsaicin, the pungent ingredient in hot chili peppers, might be useful for treating neuropathic pain, we developed the present clinical trial.

PATIENTS AND METHODS

Ninety-nine assessable patients with postsurgical neuropathic pain were entered onto this study. After stratification, patients were to receive 8 weeks of a 0.075% capsaicin cream followed by 8 weeks of an identical-appearing placebo cream, or vice versa. A capsaicin/placebo cream was to be applied to the painful site four times daily. Treatment evaluation was performed by patient-completed weekly questionnaires.

RESULTS

During the first 8-week study period, the capsaicin-cream arm was associated with substantially more skin burning, skin redness, and coughing (P < .0001 for each). Nonetheless, treatment was stopped for patient refusal or toxicity just as often while patients were receiving the placebo as compared with the capsaicin. The capsaicin cream arm had substantially more pain relief (P = .01) after the first 8 weeks, with an average pain reduction of 53% versus 17%. On completion of the 16-week study period, patients were asked which treatment period was most beneficial. Of the responding patients, 60% chose the capsaicin arm, 18% chose the placebo arm, and 22% chose neither (P = .001).

CONCLUSION

A topical capsaicin cream decreases postsurgical neuropathic pain and, despite some toxicities, is preferred by patients over a placebo by a three-to-one margin among those expressing a preference.