Extracardiac conduit fontan procedure: early and intermediate results

OBJECTIVE

The extracardiac Fontan procedure, as compared with classic atriopulmonary connections, may have the potential for optimizing ventricular and pulmonary vascular function by maximizing the laminar flow principle, by the avoidance of intra-atrial suture lines and cardiac manipulation, and by minimizing cardiopulmonary bypass time. In this study the clinical results of this procedure are assessed.

METHODS

From January 1990 until January 1997, 45 patients (33 males and 12 females) with a median age of 4.0 years (range 2.7-38 years) underwent an extracardiac Fontan procedure for univentricular physiology. The underlying diagnoses included tricuspid atresia (n=19), double-inlet left ventricle (n=11), and complex anomalies (n=15). Forty patients (89%) were in sinus rhythm. The median ventricular ejection fraction was 60%. In 37 patients (82%) the procedure was staged.

RESULTS

Median cardiopulmonary bypass time was 72 min, with a decrease to a median time of 24 min in the last ten patients. Aortic cross-clamping was avoided in 33 patients (73%). The intraoperative Fontan pressure and transpulmonary gradient were low: 13.6+/-3.2 and 8.5+/-3.9 mmHg, respectively. Transient supraventricular tachyarrhythmias were observed in six patients (13%). There was no early or late mortality. At a median follow-up of 64 months (range 26-105 months), 39 patients (87%) were in NYHA class I, four (9%) were in NYHA class II, and two (4%) were in class III. Forty patients (89%) remained in sinus rhythm. The median ventricular ejection fraction was 59%. The median arterial oxygen saturation raised from 82% preoperatively to 97%. Functional class (P=0.02), maintenance of sinus rhythm (P=0.04), and preservation of ventricular function (P=0.05) was superior in patients who were appropriately staged. None of the patients had atrial thrombus, chronic pleural effusions, or protein losing enteropathy.

CONCLUSIONS

In the majority of patients, the extracardiac Fontan procedure, when performed as a staged procedure, provides excellent early and midterm results in terms of quality of life, maintenance of sinus rhythm, and preservation of ventricular function.

Alpha1-antichymotrypsin globules within hepatocytes in patients with chronic hepatitis C and cirrhosis

Alpha1-antichymotrypsin (A1AC) is an acute phase serine protease inhibitor, similar to alpha1-antitrypsin (A1AT) in amino acid sequence. A1AT deficiency is known to be associated with emphysema and cirrhosis; deficiency of serum A1AC has been reported to be associated with emphysema, childhood asthma, and cryptogenic cirrhosis. The hepatocyte globules associated with A1AT deficiency have been well described; A1AC deficiency also has been reported to be associated with hepatocyte globules. The aim of this study was to describe the globules of A1AC and to compare them with A1AT globules. Immunohistochemistry for A1AC and A1AT was performed on liver biopsy specimens from 15 hepatitis C virus (HCV)-positive cirrhotic patients, 14 non-HCV cirrhotic patients, and 12 other patients with chronic hepatitis C but no cirrhosis, all of whom had known serum levels of A1AC; most had known serum levels of A1AT. Five of 15 HCV-positive cirrhotic patients, 1 of 14 non-HCV cirrhotic patients, and 1 of 12 noncirrhotic chronic hepatitis C patients had A1AC globules. Two of 15 HCV-positive cirrhotic patients and 2 of 14 non-HCV cirrhotic patients had A1AT globules. Histologically, the globules of A1AC were similar to those of A1AT but were smaller and fewer; the PAS/D stain was not as helpful for A1AC as it was for A1AT; immunohistochemistry was most useful. There was not a good correlation between serum levels of A1AC and its globules in hepatocytes. A1AC globules should be included in the differential diagnosis of hepatocyte inclusions.

Drug-related deaths among recently released prisoners in the Strathclyde Region of Scotland

Drug abuse and its consequences are everyday problems encountered globally, and Scotland is no exception. During a study of drug-related deaths in the Strathclyde region of Scotland it was noted that known drug users who had recently been released from prison were at high risk of dying from a drug overdose. The majority of deaths occurred within one week of the release date and polydrug use was prevalent. Morphine was the most frequently encountered drug and this was found in combination with benzodiazepines in a significant number of cases. This paper highlights the dangers of resuming drug consumption following a period of abstinence.

Correlation between increased colloid osmotic pressure and the resolution of refractory ascites after transjugular intrahepatic portosystemic shunt

BACKGROUND

This study compared the changes in serum albumin, globulin, and colloid osmotic pressure (COP) before and after transjugular intrahepatic portosystemic shunt (TIPS) or large volume paracentesis (LVP) in patients with ascites.

METHODS

Of 23 patients with refractory ascites, 17 had TIPS and 6 had LVP with infusion of albumin. Colloid osmotic pressure measurements were calculated, using the formula previously proposed by Hoefs: COP = A (1.058G + 0.163A + 3.11) where A = serum albumin and G = serum globulin.

RESULTS

After 1 month, ascites resolved in 9 of the 17 patients who had TIPS and in none of the 6 who had LVP. Colloid osmotic pressure increased significantly in patients whose ascites resolved after TIPS. Colloid osmotic pressure did not change in the patients whose ascites did not resolve after TIPS, and COP decreased significantly in the LVP group. A statistically significant difference was found in the pre-TIPS COP measurements between those patients who had resolution of ascites and those who did not. A pre-TIPS COP of < or =20 mm Hg predicted resolution of ascites with an 88% sensitivity and a 78% specificity.

CONCLUSIONS

Serum COP increased significantly in patients with resolution of ascites but remained unchanged in patients with persistent ascites after TIPS. Serum COP decreased after LVP. A statistically significant difference in the pre-TIPS COP was found between patients whose ascites resolved and patients having persistent ascites.

Biochemical and viral response to consensus interferon (CIFN) therapy in chronic hepatitis C patients: effect of baseline viral concentration. Consensus Interferon Study Group

OBJECTIVE

The effect of baseline viral concentration on response was assessed as part of a multicenter phase 3 trial evaluating the safety and efficacy of CIFN therapy for chronic HCV infection.

METHODS

Patients (n = 472) received either CIFN 9 microg or IFN alpha-2b 3 MU subcutaneously t.i.w. for 24 wk, followed by 24 wk of observation.

RESULTS

Efficacy was assessed by the percentage of patients who achieved normal ALT values or undetectable HCV RNA values (using RT-PCR with a sensitivity of 100 copies/ml). There was a clear relationship between baseline viral concentration and either ALT or HCV RNA response; patients with lower titer HCV RNA had better response rates. End-of-treatment HCV RNA responses were better for patients with low viral concentrations treated with CIFN (51%) than for patients treated with IFN a-2b (31%) (p = 0.03). ALT responses in patients with low viral concentrations were 60% for CIFN-treated patients and 27% for IFN alpha-2b-treated patients (p < 0.01) at the end of treatment. Patients with high titer HCV RNA were more likely to have a sustained HCV RNA response after treatment with CIFN 9 microg, compared with those treated with IFN alpha-2b (7% vs 0%, p = 0.03).

CONCLUSIONS

Both genotype and baseline viral concentration were independent factors that affected response to interferon.

Developing Collaborative Partnerships in Continuing Nursing Education: Walking the Talk

The purpose of this article is to describe and analyze a reciprocal partnership developed among four university-based continuing education providers in Wisconsin. Members of this partnership collaborated in developing a statewide program to address the educational needs of nurses moving from acute or long-term care into community nursing. Components of the reciprocal partnership model were applied in developing this program. The partners identified that, despite the initial time investment, the collaborative approach was an advantage. The collaborative approach enhanced the quality of the program developed and reached a wider audience. Continuing nursing educators may want to consider partnership arrangements for program development and implementation.

Calculation of esophageal variceal wall tension by direct sonographic and manometric measurements

BACKGROUND

LaPlace's law determines the wall tension of a tubular system by measuring the radius (r), wall thickness (w), and pressure gradient of a tubular structure: wall tension = pressure gradient x r/w. In theory, the determination of wall tension could provide the most accurate method of predicting the likelihood of esophageal variceal rupture. Using high-resolution endoluminal sonography, we measured the variceal wall thickness and radius. Using direct needle puncture, we measured the intravariceal pressure in three patients. We then calculated the wall tension by the LaPlace equation for each of seven varices.

METHODS

A 20 MHz ultrasonographic transducer was used to image esophageal varices. Outer and inner variceal wall circumferences were measured at a cross section of each varix. The radius and wall thickness of each varix were then calculated. Pressure measurements were obtained in the esophageal lumen and variceal lumen by direct needle puncture of the varices. The pressure gradient was then calculated (esophageal lumen - variceal lumen).

RESULTS

The wall tension of the varices from three patients was determined. There was a linear relation (r = 0.88) between the wall tension and pressure gradient.

CONCLUSIONS

This is a novel technique by which esophageal variceal wall tension can be directly measured. Such information may be useful in the future treatment of patients with portal hypertension by which risk stratification may be determined and pharmacologic response to therapy may be measured.

The effects of intrinsic sympathomimetic activity on beta-blocker efficacy for treatment of neurocardiogenic syncope

To compare the efficacy and side effects of beta-blockers with intrinsic sympathomimetic activity (ISA) to those without ISA, we retrospectively reviewed patients diagnosed with neurocardiogenic syncope (NCS) as determined by head-up tilt table testing. Four hundred and thirty-one patients (mean age of 57 +/- 25 years) underwent head-up tilt table testing for syncope of unknown etiology, of which 120 patients were diagnosed with NCS; 87 of these patients were treated with beta-blocker therapy. Only 56 patients could be contacted during follow-up. Twenty-eight patients were treated with beta-blockers with ISA (acebutolol or pindolol) and 28 received beta-blockers without ISA (atenolol or metoprolol) based on physician preference and followed for up to 2 years. During the follow-up period, beta-blockers with or without ISA had comparable clinical efficacy in suppressing recurrent syncope in patients with NCS. However, beta-blockers with ISA were better tolerated and caused less fatigue (32% side effects) as compared to those without ISA (50% side effects; p = 0.23). The benefits of beta-blockers with ISA were more pronounced in patients less than 60 years old (19% side effects with beta-blocker with ISA as compared to 85% side effects with beta-blocker without ISA; p = 0.0004). Beta-blockers without ISA appear to be better tolerated and caused less fatigue in patients 65 years old or greater (20%) than in patients less than 65 years old (85%; p = 0.0002).

Water content, raffinose, and dehydrins in the induction of desiccation tolerance in immature wheat embryos

Desiccation tolerance is initiated in wheat (Triticum aestivum L.) embryos in planta at 22 to 24 d after anthesis, at the time that the embryo water content has decreased from about 73% fresh weight (2.7 g water/g dry weight) to about 65% fresh weight (1.8 g water/g dry weight). To determine if desiccation tolerance is fully induced by the loss of a relatively small amount of water, detached wheat grains were treated to reduce the embryo water content by just a small amount to approximately 69% (2.2 g water/g dry weight). After 24 h of such incipient water loss, subsequently excised embryos were able to withstand severe desiccation, whereas those embryos that had not previously lost water could not. Therefore, a relatively small decrease in water content for only 24 h acts as the signal for the development of desiccation tolerance. Embryos that were induced into tolerance by a 24-h water loss had no detectable raffinose. The oligosaccharide accumulated at later times even in embryos of detached grains that had not become desiccation tolerant, although tolerant embryos (i.e. those that previously had lost some water) contained larger amounts of the carbohydrate. It is concluded that desiccation tolerance and the occurrence of raffinose are not correlated. Immunodetected dehydrins accumulated in embryos in planta as desiccation tolerance developed. Detachment of grains induced the appearance of dehydrins at an earlier age, even in embryos that had not been made desiccation tolerant by incipient drying. It is concluded that a small reduction in water content induces desiccation tolerance by initiating changes in which dehydrins might participate but not by their interaction with raffinose.

High-resolution endoluminal sonography assessment of the hematocystic spots of esophageal varices

BACKGROUND

Many variables are associated with an increased potential for esophageal variceal rupture, especially the presence of hematocystic spots and other red signs on upper endoscopy. The etiology of hematocystic spots is unknown. High-resolution endoluminal sonography has been shown to be an accurate and sensitive imaging modality for detection, as well as the qualitative and quantitative assessment of esophageal varices. Because the high-resolution endoluminal sonography transducer permits detailed resolution of submucosal structures thereby allowing more precise examination of the actual wall of the varix, we sought to image variceal hematocystic spots in an effort to better define their anatomy.

METHODS

Simultaneous upper endoscopy and high-resolution endoluminal sonography were performed in 68 patients with cirrhosis. Endoscopy was performed as part of screening for varices during evaluation for liver transplantation or in patients with previous presumed variceal bleeding. On endoscopy and high-resolution endoluminal sonography, two independent reviewers identified the same 10 patients having esophageal varices with hematocystic spots. The patients who had bled from their varices had not received prior endoscopic treatment.

RESULTS

Hematocystic spots as seen with high-resolution endoluminal sonography imaging appeared as saccular aneurysm like projections on the variceal surface in 6 of 10 patients. Four of six patients would later have recurrent bleeding; two of these patients were again noted to have hematocystic spots on endoscopy with a similar corresponding high-resolution endoluminal sonography appearance. Patients without hematocystic spots did not have similar high-resolution endoluminal sonography imaging.

CONCLUSION

Aneurysm-like projections in the wall of varices may represent focal weaknesses of the variceal wall and thus play a role in the pathophysiology of esophageal variceal rupture. The present findings may help to explain why there is an increased risk of variceal hemorrhage associated with the presence of hematocystic spots on esophageal varices.

Repeat exposure to incremental doses of acetaminophen provides protection against acetaminophen-induced lethality in mice: an explanation for high acetaminophen dosage in humans without hepatic injury

In studies designed to simulate a clinical observation in which an individual became tolerant to normally lethal doses of acetaminophen (APAP), mice were pretreated with increasing doses of APAP for 8 days and challenged on day 9 with normally supralethal doses of APAP. These animals developed minimal hepatotoxicity after a challenge dose with a fourfold increase in LD50 to 1,350 mg/kg. The pretreatment regimen resulted in hepatic changes including: centrilobular localization of 3-(cysteine-S-yl)APAP protein adducts, selective down-regulation of cytochrome P4502E1 (CYP2E1) and CYP1A2 that produced the toxic metabolite, N-acetyl-p-benzoquinone imine, higher levels of reduced glutathione (GSH), centrilobular inflammation, and a fourfold increase in hepatocellular proliferation. The protection against the lethal APAP doses afforded by pretreatment is secondary to these changes and to the associated regional shift in the bioactivation of the APAP challenge dose from centrilobular to periportal regions where CYP2E1 is not found, protective GSH is more abundant, and where cell-proliferative responses are better able to sustain repair. This shift in APAP bioactivation results in less-intense covalent binding that is more diffuse and spread uniformly throughout the hepatic lobe, most likely contributing to protection by delaying the early onset of liver injury that has been generally associated with centrilobular localization of the adducts. Intervention of APAP pretreatment-induced cell division in mice with colchicine left them resistant to a 500-mg/kg (normally lethal) dose of APAP, but unable to survive a 1,000-mg/kg APAP challenge dose. The data demonstrate multiple mechanistic components to the protection afforded by APAP pretreatment. Whereas metabolic and physiological changes not dependent on cell proliferation are adequate to protect against 500 mg/kg APAP, these changes plus a potentiated cell-proliferative response are necessary for protection against the supralethal 1,000-mg/kg APAP dose. Furthermore, the data document an uncoupling of the traditional association between covalent binding and toxicity, and suggest that the assessment of toxicity following repeated or chronic APAP exposure must consider altered drug interactions and parameters besides those historically used to assess acute APAP overdose.

Laryngeal cancer: is computed tomography a valuable imaging technique? A retrospective analysis

OBJECTIVE

Our objectives were threefold: to evaluate the sensitivity and specificity of laryngeal computed tomography (CT) in the evaluation of laryngeal cancer, to determine the positive and negative predictive values of CT in assessing laryngeal cancer with respect to patient outcome, and to compare the CT staging of laryngeal cancer with endoscopy.

METHODS

We reviewed the records of 77 consecutive patients with endoscopically proven laryngeal cancer. All patients underwent nonhelical CT evaluation of the larynx, with 23 subsequently undergoing surgery and 54 undergoing radiotherapy. The CT findings in the surgical cohort were compared with the pathologic analysis of resected specimens and with endoscopic data using a predetermined checklist of 14 regions of surgical interest. All the CT data in the radiotherapy cohort were compared with patient outcome in an attempt to define regions of tumour involvement that may predict disease recurrence after radiotherapy.

RESULTS

CT evaluation of laryngeal cancer had an overall sensitivity of 74% and a specificity of 93%. In the radiotherapy cohort, CT had an overall positive predictive value of 51% and a negative predictive value of 62% for disease recurrence after radiotherapy. Compared with endoscopic examination, CT resulted in upgrading of clinical staging in 43% of patients in the surgical cohort and 33% of patients in the radiotherapy cohort.

CONCLUSION

Our findings suggest that, despite the superiority of CT over endoscopy in the assessment of laryngeal cancer, this imaging technique is weak in staging advanced laryngeal cancer and is poor in predicting clinical outcome following radiotherapy.

Correlates of health-related quality of life in upper aerodigestive tract cancer patients

Reflecting a limited understanding of the definition and determinants of health-related quality of life (HRQoL), the majority of research in this field has concentrated upon the effect of disease- and treatment-related variables. That work specifically investigating HRQoL among upper aerodigestive tract (UADT) cancer patients is no exception to this observation. Treating subject-related and non-subject-related variables separately, the aim of this study was to investigate predictors of global HRQoL rating in a sample of UADT cancer patients, concentrating upon the relative importance of sociodemographic and clinical variables. A cross-sectional study design was used with a sample of 188 UADT cancer patients. Global HRQoL was assessed using the EORTC QLQ-C30 instrument, global domain (global QoL). Other study variables were collected by subject interview and chart review. Two multivariate regression models were independently developed, containing, respectively, subject-rated and non-subject rated variables. In the model containing subject-rated predictors of global QoL, emotional, breathing, physical, financial, pain and appetite problems were significant predictors (F = 14.6, p < 0.0001 and r2 = 0.54). Among non-subject-rated sociodemographic and clinical variables tested, unemployment, older age, female gender, being dentate and a more advanced disease stage predicted worse global QoL rating, while oral as opposed to pharyngeal or laryngeal cancer predicted a better global QoL rating (F = 5.1, p < 0.0001 and r2 = 0.21). In the latter model, a greater proportion of the variance was explained by sociodemographic variables than by clinical variables.

Early hepatitis C virus-RNA responses predict interferon treatment outcomes in chronic hepatitis C. The Consensus Interferon Study Group

In previous studies employing interferons (IFNs) in the treatment of chronic hepatitis C, there have been few reliable predictors of sustained responses. We retrospectively evaluated the predictive value of hepatitis C virus (HCV)-RNA measurements in the first few months during consensus interferon (CIFN) treatment using a sensitive reverse-transcriptase polymerase chain reaction assay to determine sustained responses. Data from two large treatment trials, one of IFN-naive patients and one of retreated relapsers and nonresponders, were used, including serum samples at 2-week intervals in the naive study and 8-week intervals in the retreatment study. Patients received initial CIFN (9 microgram) treatment for 6 months and were assessed 6 months after treatment. There were 28 sustained viral responders of 232 CIFN-treated patients. Of the sustained responders, 48% had already cleared HCV RNA from serum (<100 copies/mL) by week 2, 78% by week 4, 81% by week 6, and 96% by week 12. Patients with early HCV-RNA clearance were more likely to have sustained responses than those who responded later. Early clearance of HCV from serum was also associated with greater likelihood of a sustained response to 48 weeks of retreatment with 15 microgram CIFN. Ninety-five percent of the sustained responders were HCV-RNA-negative by week 8 of retreatment. Early assessment of HCV RNA may help in the prediction of sustained responses to IFN and allow the value of continued treatment to be determined early in the course of IFN therapy.

Effects of ethanol and nitrous oxide, alone and in combination, on mood, psychomotor performance and pain reports in healthy volunteers

Ethanol and nitrous oxide (N2O) are sometimes used in combination by recreational drug users. The subjective effects of this drug combination have not been examined, and was the basis for the present study. The effects of both drugs were examined alone and in combination. Dependent measures included mood, cognitive/psychomotor performance, and pain reports. Volunteers (N = 11) first consumed a drink containing ethanol (0, 0.25, or 0.5 g/kg), waited for 15 min, and then inhaled 100% oxygen (placebo) or 30% N2O in oxygen for 35 min. Thirty minutes into the inhalation, subjects immersed their non-dominant forearm in icy water for 3 min. Ethanol increased ratings of 'feel drug effect' and 'drunk'. N2O affected several mood ratings, impaired cognitive/psychomotor performance, and reduced pain reports. There were several instances of ethanol potentiating the effects of N2O, and instances in which the drug combination produced effects that neither drug alone did. Ethanol did not potentiate the analgesic effects of N2O. Overall, the data obtained in the study did not convincingly demonstrate that the drug combination of N2O and ethanol had a greater abuse liability than did N2O alone, at the doses that were tested.

Determining cost drivers for pediatric home health services

A variety of cost constraints threaten the financial viability of home health agencies. Thus, tools must be developed that expand the critical information resources that will be the key ingredient in successfully navigating the challenges in the volatile home health market. Identifying and analyzing the core processes with the pediatric home care team provided a template that could be used with other agency patient populations by producing cost trajectories based on anticipated care requirements and capturing information that could be used for both internal and external benchmarking. The cost drivers of key processes and activities must be known so that they can be controlled and appropriate rates for capitation contracts can be established. Activity-based management uses cost driver analysis, activity analysis and performance analysis, to determine strategies for redirecting the work processes and agency activities to achieve lasting cost reductions.

Relationship between biochemical and virological responses to interferon therapy in chronic hepatitis C infection. Consensus Interferon Study Group

We have investigated the relationship between serum alanine aminotransferase (ALT) and hepatitis C virus (HCV) RNA in the assessment of responses to interferon (IFN) therapy in chronic HCV infection. Data from 704 patients with HCV infection who were randomized to receive consensus IFN-alpha (CIFN) 3 micrograms (n = 232 patients) or 9 micrograms (n = 232 patients), or IFN-alpha 2b 3 million units (MU) (n = 240 patients), were used for these analyses. All patients were treated three times weekly. Hepatitis C viral RNA (HCV RNA) was determined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) with a lower limit of detection of 100 copies ml-1. Of patients with normal serum ALT concentrations, 53% (120/225) had undetectable HCV RNA at the end-of-treatment period and 47% (51/109) had undetectable HCV RNA at the end of the post-treatment observation period. In contrast, of the patients with undetectable HCV RNA, 75% (120/161) and 84% (51/61) had normal serum ALT activities at the end-of-treatment and post-treatment observations periods, respectively. The majority of patients with undetectable HCV RNA had normal ALT values. In contrast, only half of the patients with normal ALT values were negative for HCV. End-of-treatment HCV RNA response also better predicted sustained virological response than did end-of-treatment ALT response.

In vivo comparison of esophageal varices at and above the diaphragmatic high pressure zone using high resolution endoluminal sonography

Our objective in this study was to use high resolution endoluminal sonography to compare the size of esophageal varices within 5 cm of and at the esophageal high pressure zone. We carried out the study in 36 patients with endoscopically proven esophageal varices. A 20-MHz 6.2F ultrasound catheter was passed through a 34F endoscope and used to image esophageal varices as it was slowly withdrawn through the high pressure zone (the level at which the diaphragm was imaged) and into the body of the esophagus approximately 5 cm above the high pressure zone. All images were captured on videotape and reviewed by one of the investigators. The mean, total, and percent cross-sectional surface areas occupied by varices were calculated and then compared within 5 cm and at the esophageal high pressure zone. Six of 36 (17%) patients had no varices imaged at the high pressure zone but did have varices imaged in the distal esophagus. The mean cross-sectional surface area per varix at the high pressure zone (0.036+/-0.006 cm2) was significantly less (p < or = 0.0001) than the mean cross-sectional area per varix 5 cm above the high pressure zone (0.142+/-0.018 cm2). The average total cross-sectional surface area occupied by varices at the high pressure zone (0.137+/-0.034 cm2) was significantly less (p < 0.0001) than the average cross-sectional surface area occupied by varices 5 cm above the high pressure zone (0.672+/-0.080 cm2). The mean percent esophageal wall cross-sectional surface area occupied by varices at the high pressure zone (16%) was significantly less (p < or = 0.0001) than 5 cm above the high pressure zone (49%). We conclude that the mean, total, and percent cross-sectional surface areas of esophageal varices at the high pressure zone are significantly less than those 5 cm above the high pressure zone.

Overexpression of p53 protein does not predict local-regional control or survival in patients with early-stage squamous cell carcinoma of the glottic larynx treated with radiotherapy

PURPOSE

Nonfunctional or mutated p53 protein (m-p53) is found in a myriad of solid tumors in humans. m-p53 is believed to confer radioresistance through inhibition of radiation-induced apoptosis. This study was carried out to determine if the overexpression of p53 in squamous cell carcinomas (SCC) of the glottic larynx treated with radiation therapy alone carried a poorer prognosis than normal wild-type p53 (w-p53) and could, therefore, be used as a marker of radioresistance in glottic SCC.

METHODS & MATERIALS

Eighty-six patients with early-stage glottic SCC (64 T1N0, 25 T2N0 by TMN stage) treated with contemporary radiotherapy techniques to doses of 50-70 Gy were analyzed. Aberrant p53 protein was detected by immunohistochemical (IHC) staining on archival tissue samples containing original tumor specimens. Analysis of prognostic factors and treatment outcome to expression of p53 was performed. All patients were carefully selected to have comparable sites of disease, histology, early-stage disease, and treatment delivered, thus increasing the power of this study by controlling for other independent factors affecting outcome.

RESULTS

Sixty percent of patients demonstrated overexpression of p53 in tissue samples. Accumulation of p53 was not predictive of tumor grade, stage, or smoking status prior to diagnosis. p53 status was not predictive of treatment outcome parameters including local-regional failure rate and disease-free survival rate. Factors significantly affecting treatment outcome were stage and dose of radiotherapy in T2 patients (50 Gy vs. > 62 Gy).

CONCLUSION

m-p53 protein detected by IHC staining was not predictive as a prognostic factor for clinical outcome following radiation therapy for early-stage glottic SCC. This is in general agreement with other recently published studies of laryngeal carcinoma patients treated with radiation or surgery. At the present time, p53 status should not be used as a marker for prognosis and clinical outcome in laryngeal SCC.