Citations

AbstractReoperation for persistent or recurrent hyperparathyroidism is more hazardous than is primary cervical exploration and is also much less likely to result in cure of the disease. Only 21 of 34 reoperations (62%) were successful during the period 1970 through 1972 at the Mayo Clinic, compared with success in 312 of 327 primary operations (95%). In 9 patients who had their initial exploration at this institution, the most common cause of failure at the first operation was inadequate treatment of multiglandular disease; in 25 patients who were first operated on elsewhere, missed adenomas were far more common.Parathyroid arteriography and selective venous sampling with parathyroid hormone assays should improve the results of reoperation by providing preoperative localization of hyperfunctioning parathyroid glands in difficult cases. These procedures, however, are expensive and technically difficult, and they are not always successful. They are also associated with a definite morbidity, which must be weighed against any anticipated benefits. The systematic evaluation and treatment of patients facing reoperation for hyperparathyroidism should be undertaken in special centers accustomed to dealing with these difficult problems.

Prooxidents can induce reversible inhibition or irreversible inactivation and degradation of the mitochondrial enzyme aconitase. Cardiac ischemia/reperfusion is associated with an increase in mitochondrial free radical production. In the current study, the effects of reperfusion-induced production of prooxidants on mitochondrial aconitase and proteolytic activity were determined to assess whether alterations represented a regulated response to changes in redox status or oxidative damage. Evidence is provided that ATP-dependent proteolytic activity increased during early reperfusion followed by a time-dependent reduction in activity to control levels. These alterations in proteolytic activity paralleled an increase and subsequent decrease in the level of oxidatively modified protein. In vitro data supports a role for prooxidants in the activation of ATP-dependent proteolytic activity. Despite inhibition during early periods of reperfusion, aconitase was not degraded under the conditions of these experiments. Aconitase activity exhibited a decline in activity followed by reactivation during cardiac reperfusion. Loss and regain in activity involved reversible sulfhydryl modification. Aconitase was found to associate with the iron binding protein frataxin exclusively during reperfusion. In vitro , frataxin has been shown to protect aconitase from [4Fe-4S] 2+ cluster disassembly, irreversible inactivation, and, potentially, degradation. Thus, the response of mitochondrial aconitase and ATP-dependent proteolytic activity to reperfusion-induced prooxidant production appears to be a regulated event that would be expected to reduce irreparable damage to the mitochondria.

Purpose To compare once-daily radiation therapy (qdRT) with hyperfractionated accelerated radiation therapy (HART) after two cycles of induction chemotherapy. Patients and Methods Eligible patients were treatment naive, and had stage IIIA and B unresectable non-small-cell lung cancer, Eastern Cooperative Oncology Group performance status 0/1, and normal organ function. Induction chemotherapy consisted of two cycles of carboplatin area under time-concentration curve 6 mg/mL · min plus paclitaxel 225 mg/m2 on day 1. RT consisted of arm 1 (qdRT), 64 Gy (2 Gy/d), versus arm 2 (HART), 57.6 Gy (1.5 Gy tid for 2.5 weeks). A total of 388 patients were needed to detect a 50% increase in median survival from 14 months of qdRT to 21 months of HART; accrual was not achieved and the study closed prematurely. Results Of 141 patients enrolled, 83% were randomly assigned after chemotherapy to qdRT (n = 59) or HART (n = 60). Median survival was 20.3 and 14.9 months for HART and qdRT, respectively (P = .28). Overall response was 25% and 22% for HART and qdRT, respectively (P = .69). Two- and 3-year survival was 44% and 34% for HART, and 24% and 14% for qdRT, respectively. Grade ≥ 3 toxicities included esophagitis in 14 v nine patients, and pneumonitis in 0 v 6 patients for HART and qdRT, respectively. Any subsequent trials of the HART regimen must address the issues that led to early closure, including slow accrual, logistics of HART, mucosal toxicity, and the fact that concurrent chemoradiotherapy now seems more effective than sequential treatment. Conclusion After two cycles of induction chemotherapy with carboplatin-paclitaxel, HART is feasible with an acceptable toxicity profile. Although statistical significance was not achieved and the study closed early, there was a positive statistical trend suggesting a survival advantage with the HART regimen.

Purpose To determine whether a response classification based on integration of fluorine-18–fluorodeoxyglucose positron emission tomography (FDG-PET) into the International Workshop Criteria (IWC) provides a more accurate response assessment than IWC alone in patients with non-Hodgkin's lymphoma (NHL). Patients and Methods Fifty-four patients with aggressive NHL who underwent FDG-PET and computed tomography 1 to 16 weeks after four to eight cycles of chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone were assessed for complete response (CR), unconfirmed CR (CRu), partial response (PR), stable disease (SD), and progressive disease (PD) by the IWC and by integrated IWC and FDG-PET (IWC+PET). Progression-free survival (PFS) was also compared between IWC- and IWC+PET-assigned response designations. Results By IWC, 17 patients had a CR, seven had a CRu, 19 had a PR, nine had SD, and two had PD. In comparison, by IWC+PET, 35 patients had a CR, 12 had a PR, six had SD, one had PD, and zero had a CRu. In separate multivariate models, PFS was significantly shorter in patients with PR than in those with a CR using IWC (hazard ratio [HR], 8.9; P = .021) or IWC+PET (HR, 29.7; P = .0003). However, when the two classifications were included in the same multivariate model, only IWC+PET was a statistically significant independent predictor for PFS (P = .008 v P = .72 for IWC). In addition, when patients with a PR by IWC and a CR by IWC+PET were compared with those with a CR by IWC and a CR by IWC+PET, there was no significant difference in PFS (HR, 1.6; P = .72), indicating that IWC+PET identified a subset of IWC-PR patients with a more favorable prognosis. Conclusion Compared with IWC, the IWC+PET-based assessment provides a more accurate response classification in patients with aggressive NHL.

Background— Obesity is associated with coronary artery calcification (CAC), a marker of the presence and extent of subclinical coronary atherosclerosis. Obesity adds incremental information in identifying those at higher risk of coronary heart disease to traditional risk factor assessment. The present study examined associations between obesity measures and progression of CAC in those at higher (≥10%) and lower (<10%) 10-year coronary heart disease risk according to the Framingham risk equation. Methods and Results— In this study, 443 asymptomatic white individuals >30 years of age (243 men) had baseline and follow-up CAC measurements an average of 8.9 years apart. Multivariable linear regression models were fit to determine associations of obesity measures at baseline with progression of CAC defined as log e of the difference between follow-up and baseline CAC area plus 1 divided by time (in years) between examinations, adjusting for baseline CAC quantity, age, sex, baseline hypertension status, and baseline cholesterol level. Among 329 participants (74.3%) in the lower-risk group, waist circumference ( P =0.024), waist-to-hip ratio ( P <0.001), body mass index ( P =0.036), and being overweight compared with being underweight or of normal weight ( P =0.008) were each significantly positively associated with progression of CAC. Among those at higher coronary heart disease risk, no baseline obesity measures were associated with CAC progression. Conclusions— Various measures of obesity were associated with increased progression of CAC in those at lower risk of coronary heart disease. Future studies examining the effectiveness of weight reduction strategies in reducing CAC progression among those with an otherwise favorable risk factor profile may be warranted.