Long-term results of 100 consecutive comprehensive neck dissections: implications for selective neck dissections

OBJECTIVE: The optimal surgical procedure for the neck in patients with squamous head and neck cancers is controversial. Selective neck dissections have replaced modified radical neck dissections as the procedure of choice for the clinically negative (N0) neck and are now being considered for patients with early-stage neck disease. We report the long-term local recurrence rates in 100 consecutive patients undergoing a radical or modified radical neck dissection for clinically positive (N+) and N0 neck disease and review comprehensively the literature reporting and comparing regional control rates for both neck dissection types. PATIENTS: The clinical records of 100 consecutive patients who underwent a comprehensive neck dissection (levels I-V) for squamous head and neck cancers with a minimum of a 2-year follow-up were retrospectively reviewed for primary site of disease, clinical and pathologic neck status, histopathologic grade, neck dissection type, and the site and time of recurrence. RESULTS: Complete data were available for 97 patients on whom 99 neck dissections were performed. Three patients died from unknown causes. Seventy-six patients with N+ disease underwent a therapeutic neck dissection, while 24 patients with clinically N0 disease underwent an elective dissection. The overall neck recurrence rate in patients with controlled primary disease was 7%. The neck or regional failure rate for patients completing the recommended adjuvant radiotherapy was 4%. Six (25%) of 24 patients with clinically N0 disease had occult metastases. The recurrence rate for this group was 4%. CONCLUSION: Further study is needed to determine the optimal surgical management of the N0 and limited N+ neck.     

Labor market costs of illness: prevalence matters

We present a model of the labor market effects of health impairments. In particular, we describe several economic models in which health affects worker productivity and the demand for and supply of market labor services. These models provide a framework for estimating the social cost of prevalent health impairments - a necessary step in conducting cost-benefit analyses and in determining the cost-effectiveness of potential health interventions from a broader social perspective. Our approach suggests that several measures used in the literature provide an incomplete and systematically biased assessment of the economic impact of health impairment or of the treatment of illness and impairment. The problem arises because of the reliance on an approximation at the firm level and from the bias from the neglect of the effect of impairment in shifting the labor market equilibrium. If the illness is prevalent, the effects on labor market equilibrium wage rates could be substantial. In addition, many analyses also ignore the effects of illness on producers' surplus.     

Estimation of errors in determining intrathoracic blood volume using thermal dilution in pigs with acute lung injury and haemorrhage

Background. Global end diastolic volume (GEDV) has a constantand predictable relationship to intrathoracic blood volume (ITBV).The present study assesses the difference between ITBV derivedfrom GEDV and ITBV measured directly in pigs with acute lunginjury (ALI) and mild haemorrhage. Methods. We caused ALI in 12 anaesthetized pigs by i.v. injectionof oleic acid and removed 10% of estimated blood volume. EVLW,GEDV, ITBV (COLD; Pulsion Medical Systems),     

Hemorrhagic complications during long-term postoperative warfarin administration in patients undergoing lower extremity arterial bypass surgery

Lower extremity bypass procedures restore function and prevent amputation in many patients with severe peripheral arterial occlusive disease. The regular postoperative use of aspirin offers the dual benefit of extending bypass patency and patient survival. Previous trials of adjunctive oral anticoagulant therapy with warfarin have infrequently combined warfarin with aspirin. We hypothesized that the addition of oral anticoagulant therapy would further enhance the benefits of aspirin but may increase the risk of clinically important bleeding. Eligible patients (N = 831) scheduled for elective lower extremity arterial bypass surgery were randomized to receive either warfarin plus aspirin (WA) (n = 418) or aspirin alone (n = 413). At monthly intervals, the warfarin dose was adjusted to a target international normalized ratio (INR) of 1.4 to 2.8; both groups received aspirin (325 mg/d). The end point of major hemorrhagic events, defined as intracranial hemorrhage or bleeding that required intervention, is reported, and INR values and compliance with warfarin therapy are presented. Major hemorrhagic events occurred more frequently in the WA group (35 in the WA group vs 15 in the aspirin group; p = .02) during a mean follow-up of 38 months. In the WA group, an intracranial hemorrhage occurred in six patients (two had an INR > 3.0), of whom four died; one subdural hemorrhage occurred in the aspirin group. Transfusions and interventions for bleeding were more frequent in the WA group, as were minor bleeding events. Of the 8,946 INR determinations, 58% were in the target range, whereas a higher value occurred in 10% and a lower value in 32%. Compliance with warfarin was maintained in 65% of the patients after the first year of observation. In patients with elective lower extremity bypass procedures, the postoperative adjunctive use of warfarin with aspirin increased the risk of major hemorrhagic events. Most of these events occurred when the INR was in the target range.     

Age-associated changes in the expression pattern of cyclooxygenase-2 and related apoptotic markers in the cancer susceptible region of rat prostate

Senescence-associated changes in the prostate are believed to play an important role in the genesis of prostate cancer. In order to provide further information on how aging increases the prostate susceptibility to cancer, we examined the pattern of cyclooxygenase (COX)-2 expression and the concomitant alterations in prostaglandin E(2) (PGE(2)) synthesis in the prostate glands of 4-, 10-, 50- and 100-week-old Fischer 344 rats. This was carried out in the prostatic areas where hormone-induced tumors arise, namely the periurethral ducts of the dorsolateral prostate (DLP). Age-associated changes were also evaluated for pro- and anti-apoptotic factors linked to COX-2 signaling and known to be involved in the normal development of the prostate gland as well as in carcinogenesis. COX-2 expression was increased in the DLP in an age-dependent manner where senescent rats had >3-4-fold higher COX-2 mRNA and protein levels than their juvenile counterparts (P<0.05). The age-related changes in COX-2 were accompanied by a similar up-regulation in the PGE(2) synthesis. Evaluation of mediators of apoptotic signaling showed a significant (P<0.05) decline in the expression levels of the pro-apoptotic BAX (>6-fold) and peroxisome proliferator-activated receptor gamma (>3-fold) and in caspase-3 activity (>2-fold) and an up-regulation of the anti-apoptotic Bcl(2) (>8-fold), PKCalpha (>2-fold) and pAkt (>4-fold) in the 100-week-old rats versus the 4-week-old animals. There was an approximately 15-fold age-dependent decrease in the pro-apoptotic ratio BAX:Bcl(2) and an increase in the anti-apoptotic variable PKCalpha(*)Bcl(2)/BAX in the senescent rats compared with the juvenile ones. These results suggest that increased COX-2 expression can be linked to the decline in the pro-apoptotic signaling in the prostate gland during aging. Subsequently, COX-2 inhibitors can be considered as a promising class of agents to attenuate the increased cell survival and, hence, protect against tumorigenesis in the aging prostate.     

Evaluation of estrous cycle stage and gender on behavioral outcome after experimental traumatic brain injury

Female sex hormones are acutely neuroprotective in experimental models of traumatic brain injury (TBI). Because hormonal profiles are known to vary with estrous cycle stage, the purpose of this study was to evaluate how pre-injury estrous stage affects motor and cognitive performance after experimental TBI. We also sought to compare post-injury behavioral performance in males vs. females. Under anesthesia, male (n=18) and female (n=35) Sprague-Dawley rats underwent either controlled cortical impact (CCI) injury (2.7 mm; 4 m/s) or sham operations. Females were grouped according to estrous stage (proestrous or non-proestrous) at the time of surgery. Motor function was assessed pre-injury and for the first 5 days after surgery using beam balance and walking tasks. Spatial memory was assessed beginning 14 days post-injury utilizing the Morris water maze (MWM) task. No significant differences were found on any task between injured females regardless of estrous cycle stage. Females performed significantly better than males on both motor tasks, but gender did not influence MWM performance. Mixed effects multivariate analysis corroborated these results by showing that pre-injury serum hormone levels had little affect on behavioral performance. The results suggest that the presence of endogenous circulating hormones, rather than hormonal status at time of injury, may confer early neuroprotection in females after TBI. The impact of early neuroprotection on later behavioral outcome and the anatomic structural specificity of hormonal neuroprotection require further study.     

Sexually transmitted diseases among American youth: incidence and prevalence estimates, 2000

CONTEXT In the United States, young people aged 15–24 represent 25% of the sexually experienced population. However, the incidence and prevalence of sexually transmitted diseases (STDs) among this age-group are unknown.
METHODS Data from a variety of sources were used to estimate the incidence and prevalence of STDs among 15–24-year-olds in the United States in 2000. The quality and reliability of the estimates were categorized as good, fair or poor, depending on the quality of the data source.
RESULTS Approximately 18.9 million new cases of STD occurred in 2000, of which 9.1 million (48%) were among persons aged 15–24. Three STDs (human papillomavirus, trichomoniasis and chlamydia) accounted for 88% of all new cases of STD among 15–24-year-olds.
CONCLUSIONS These estimates emphasize the toll that STDs have on American youth. More representative data are needed to help monitor efforts at lowering the burden of these infections.