Abstract P1-08-37: Magee equations predict pathologic response to neoadjuvant chemotherapy

Introduction: Neoadjuvant chemotherapy is used in locally advanced breast cancer to downstage the tumor, facilitating surgical management. Oncotype DX (ODX) is used to estimate the risk of distant recurrence for ER-positive breast cancers, allowing selected patients to avoid the toxicity of chemotherapy. ODX is often not possible on the small core biopsy samples. Klein et al. have shown that standard histological variables, combined with semiquantitative ER, PR, HER-2, and Ki-67 results, can provide information similar to that with ODX, using equations derived by linear regression analysis (Magee equations). We applied a modification of these equations to pretreatment core biopsies in women who received neoadjuvant chemotherapy to determine if the risk scores were predictive of pathologic response.

Methods: 25 patients who received chemotherapy for receptor positive locally advanced(21), inflammatory(3), or metastatic(1) breast cancer followed by surgical treatment of the primary site were identified from a prospective breast cancer database. Pretreatment core biopsies were reviewed by a breast pathologist and Nottingham grade, ER and PR status (% of cells staining and intensity of staining), and Her-2 status by IHC and/or FISH were recorded. Clinical tumor size was defined as the average of sizes derived from mammogram, ultrasound, MRI, PET-CT and clinical breast examination. Using these data in a modified Magee equation, the patient's recurrence score was calculated. 0-18 was considered low risk (LR), >18-<30 was considered intermediate risk (IR), and ≥30 was considered high risk (HR). Resection specimens were reviewed to define pathologic response. A good pathologic response to chemotherapy was defined as a complete pathologic response (3 cases), near complete response (2), or a response with one or more of the following; reduction in the post-treatment size of the tumor by greater than 50% compared with pretreatment imaging, a significant reduction in tumor cellularity in the tumor bed, and an inflammatory lymphohistiocytic infiltrate with tumor necrosis (6 cases). For the remaining 14 cases, the response was defined as poor (no histopathologic evidence of response to treatment). Risk scores were compared between good and poor responders using T-Test. Comparison between risk groups (HR vs IR vs LR) were made using Chi Square analysis.

Results: Magee scores ranged from 13.8-41.6 (mean 27.4) and were significantly lower in the poor responders (mean = 23, range 13.8-41.6) compared to the good responders (mean = 33, range 22-41.3, p = 0.003). Table 1 shows the distribution of response by Risk Group (p = 0.018).

Table 1: Response by Risk CategoryMagee Risk GroupLRIRHRPoor Response563Good Response038

73% of patients with high risk Magee scores had a good response to chemotherapy, compared to 21% of patient with low or intermediate scores (p = 0.01).

Conclusions: Modified Magee equations applied to pretreatment core biopsies seem to predict pathologic response to neoadjuvant chemotherapy. Use of these equations to assign risk scores may be a useful tool in deciding which ER positive breast cancer patients are likely to benefit from preoperative chemotherapy for cytoreduction, and who should go directly to surgery. These findings need to be validated in larger studies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-08-37.

Palpable breast cancers are inherently different from nonpalpable breast cancers

BACKGROUND

We examined the clinicopathologic profile of T1 cancers to determine whether palpable cancers are different from nonpalpable cancers.

METHODS

A prospective database was reviewed. Palpable T1 cancers were compared with nonpalpable T1 cancers. Initial significance was determined by chi2 analysis. Factors found to be significant were then reanalyzed. controlling for tumor size by logistic or linear regression, as appropriate.

RESULTS

Of 1263 T1 cancers treated between 1981 and 2000, 857 (68%) were palpable and 401 (32%) were nonpalpable. Palpability correlated with pathologic tumor size, mitotic grade, nuclear grade, high S-phase, lymphovascular invasion, nodal positivity, and lack of extensive intraductal component, multifocality, and multicentricity. There was no significant difference in estrogen receptor, progesterone receptor or Her-2/neu status, ploidy, or DNA index. Breast cancer-specific survival was worse for patients with palpable cancers.

CONCLUSIONS

Palpable cancers are inherently different from nonpalpable cancers, with a less diffuse growth pattern, higher metastatic potential, higher proliferative activity, more nuclear abnormalities, and a worse prognosis.

Predicting axillary nodal positivity in 2282 patients with breast carcinoma

Axillary lymph node status continues to be the single most important prognostic variable for breast cancer survival despite significant progress in the molecular and genetic characterization of breast malignancies. All patients with invasive breast cancer who underwent axillary lymph node dissection as part of their treatment were evaluated by 11 clinical and pathologic factors, including the primary lesion's T category (TNM staging system), whether the lesion was clinically palpable, the presence of lymphatic or vascular invasion, nuclear grade, estrogen and progesterone receptors, S-phase, age, HER2/neu overexpression, histology (infiltrating lobular or ductal), and ploidy. A total of 2282 axillary dissections were performed: 391 in patients with ductal carcinoma in situ (DCIS) [3 of which (0.8%) contained metastases] and 1891 in patients with invasive breast cancer [680 of which (36%) contained metastases]. Multivariate analysis of patients with invasive cancer identified four factors as independent predictors of axillary lymph node metastases: lymph/vascular invasion, tumor size, nuclear grade, tumor palpability. Among a group of 189 patients with nonpalpable, non-high-grade invasive lesions 15 mm or smaller without lymph/vascular invasion, only 6 (3%) had metastases to lymph nodes. If any three of the favorable factors were present, lymph node positivity was 6% or less. Clinical and pathologic feature of the primary lesions can be used to estimate the risk of axillary lymph node metastases. Such risk assessment can be used for the treatment decision-making process.

Epigenetic patterns in the progression of esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) arises after normal squamous mucosa undergoes metaplasia to specialized columnar epithelium (intestinal metaplasia or Barrett's esophagus), which can then ultimately progress to dysplasia and subsequent malignancy. Epigenetic studies of this model have thus far been limited to the DNA methylation analysis of a few genes. In this study, we analyzed a panel of 20 genes using a quantitative, high-throughput methylation assay, METHYLIGHT: We used this broader approach to gain insight into concordant methylation behavior between genes and to generate epigenomic fingerprints for the different histological stages of EAC. Our study included a total of 104 tissue specimens from 51 patients with different stages of Barrett's esophagus and/or associated adenocarcinoma. We screened 84 of these samples with the full panel of 20 genes and found distinct classes of methylation patterns in the different types of tissue. The most informative genes were those with an intermediate frequency of significant hypermethylation [ranging from 15% (CDKN2A) to 60% (MGMT) of the samples]. This group could be further subdivided into three classes, according to the absence (CDKN2A, ESR1, and MYOD1) or presence (CALCA, MGMT, and TIMP3) of methylation in normal esophageal mucosa and stomach, or the infrequent methylation of normal esophageal mucosa accompanied by methylation in all normal stomach samples (APC). The other genes were less informative, because the frequency of hypermethylation was below 5% (ARF, CDH1, CDKN2B, GSTP1, MLH1, PTGS2, and THBS1), completely absent (CTNNB1, RB1, TGFBR2, and TYMS1), or ubiquitous (HIC1 and MTHFR), regardless of tissue type. Each class undergoes unique epigenetic changes at different steps of disease progression of EAC, suggesting a step-wise loss of multiple protective barriers against CpG island hypermethylation. The aberrant hypermethylation occurs at many different loci in the same tissues, suggestive of an overall deregulation of methylation control in EAC tumorigenesis. However, we did not find evidence for a distinct group of tumors with a CpG island methylator phenotype. Finally, we found that normal and metaplastic tissues from patients with evidence of associated dysplasia or cancer had a significantly higher incidence of hypermethylation than similar tissues from patients with no further progression of their disease. The fact that the samples from these two groups of patients were histologically indistinguishable, yet molecularly distinct, suggests that the occurrence of such hypermethylation may provide a clinical tool to identify patients with premalignant Barrett's who are at risk for further progression.

The management of ductal carcinoma in situ of the breast

Ductal carcinoma in situ (DCIS) of the breast is a heterogeneous group of lesions with diverse malignant potential. It is the most rapidly growing subgroup within the breast cancer family with more than 42 000 new cases diagnosed in the United States during 2000. Most new cases are nonpalpable and are discovered mammographically. Treatment is controversial and ranges from excision only, to excision with radiation therapy, to mastectomy. Prospective randomized trials reveal an approximate 50% reduction in local recurrence rate overall with the addition of radiation therapy to excisional surgery, but the published prospective data do not allow the selection of subgroups in whom the benefit from radiation therapy is so small that its risks outweigh its benefits. Nonrandomized single facility series suggest that age, family history, nuclear grade, comedo-type necrosis, tumor size and margin width are all important factors in predicting local recurrence and that one or more of these factors could be used to select subgroups of patients who do not benefit sufficiently from radiation therapy to merit its use. When all patients with ductal carcinoma in situ are considered, the overall mortality from breast cancer is extremely low, only about 1-2%. When conservative treatment fails, approximately 50% of all local recurrences are invasive breast cancer. In spite of this, the mortality rate following invasive local recurrence is relatively low, about 12% with eight years of actuarial follow-up. Genetic changes routinely precede morphological evidence of malignant transformation. Lessons learned from ongoing basic science research will help us to identify those DCIS lesions that are unlikely to progress and to prevent progression in the rest.

Breast cancer after augmentation mammoplasty

BACKGROUND

It is thought that implants interfere with breast cancer diagnosis and that cancers in women who have had breast augmentation carry a worse prognosis.

METHODS

A prospective breast cancer database was reviewed, comparing augmented and nonaugmented patients for details of histology, palpability, tumor size, nodal status, mammographic status, receptor status, nuclear grade, stage, and outcome.

RESULTS

Ninety-nine cancers in augmented women and 2857 cancers in nonaugmented women were identified. Among these women, mammography was normal in 43% of those who had had augmentation and in 5% of those who had not. Augmented women were more likely to have palpable cancers (83% vs. 59%) and nodal involvement (48% vs. 36%), and less likely to have ductal carcinoma in situ (DCIS) (18% vs. 28%). When comparing only women younger than 50, the differences in invasiveness and nodal status lost significance. Cancers diagnosed in the 1990s were more likely to be nonpalpable and noninvasive than those diagnosed in the 1980s. This trend was more pronounced in the augmented population.

CONCLUSIONS

Augmented patients were more likely to have palpable cancers, although the overall stage and outcome were similar to those of nonaugmented women. Although there have been significant improvements in our ability to diagnose early breast cancer over the past two decades, mammography continues to be suboptimal in augmented women.

Differential expression of ACAT1 and ACAT2 among cells within liver, intestine, kidney, and adrenal of nonhuman primates

Two closely related enzymes with more than 50% sequence identity have been identified that catalyze the esterification of cholesterol using acyl-CoA substrates, namely acyl-CoA:cholesterol acyltransferase 1 (ACAT1) and ACAT2. Both are membrane-spanning proteins believed to reside in the endoplasmic reticulum of cells. ACAT2 has been hypothesized to be associated with lipoprotein particle secretion whereas ACAT1 is ubiquitous and may serve a more general role in cellular cholesterol homeostasis. We have prepared and affinity purified rabbit polyclonal antibodies unique to either ACAT enzyme to identify their cellular localization in liver and intestine, the two main lipoprotein-secreting tissues of the body, and for comparison, kidney and adrenal. In the liver, ACAT2 was identified in the rough endoplasmic reticulum of essentially all hepatocytes whereas ACAT1 was confined to cells lining the intercellular spaces among hepatocytes in a pattern typical of Kupffer cells. In the intestine, ACAT2 signal was strongly present in the apical third of the mucosal cells, whereas ACAT1 staining was diffuse throughout the mucosal cell, but with strong signal in goblet cells, Paneth cells, and villus macrophages. In the kidney, ACAT1 immunostaining was specific for the distal tubules and podocytes within the glomerulus. In the adrenal, ACAT1 signal was strongly present in the cells of the cortex, and absent from other adrenal cell types. No ACAT2 signal was identified in the kidney or adrenal. We conclude that only the cells of the liver and intestine that secrete apolipoprotein B-containing lipoproteins contain ACAT2, whereas ACAT1 is present in numerous other cell types. The data clearly suggest separate functions for these two closely related enzymes, with ACAT2 being most closely associated with plasma cholesterol levels.

Fields of aberrant CpG island hypermethylation in Barrett's esophagus and associated adenocarcinoma

Esophageal adenocarcinoma (EAC) is thought to develop through a multistage process in which Barrett's metaplasia progresses through low- and high-grade dysplasia to invasive cancer. Transcriptional silencing of tumor suppressor genes by promoter CpG island hypermethylation has been observed in many types of human cancer. Analysis of CpG island hypermethylation in EAC has thus far been limited to the CDKN2A (p16) gene. In this study, we extend the methylation analysis of EAC to include three other genes, APC, CDH1 (E-cadherin), and ESR1 (ER, estrogen receptor alpha), in addition to CDKN2A. Molecular analysis can provide insight into the complex relationships between tissues with different histologies in Barrett's esophagus and associated adenocarcinoma. Therefore, we have mapped the spatial distribution of methylation patterns in six esophagectomy cases in detail. Hypermethylation of the four CpG islands was analyzed by the MethyLight technique in 107 biopsies derived from these six patients for a total of 428 methylation analyses. Our results show that normal esophageal squamous epithelium is unmethylated at all four CpG islands. CDH1 is unmethylated in most other tissue types as well. Hypermethylation of ESR1 is seen at high frequency in inflammatory reflux esophagitis and at all subsequent stages, whereas APC and CDKN2A hypermethylation is found in Barrett's metaplasia, dysplasia, and EAC. When it occurs, hypermethylation of APC, CDKN2A, and ESR1 is usually found in a large contiguous field, suggesting either a concerted methylation change associated with metaplasia or a clonal expansion of cells with abnormal hypermethylation.

Telomerase reverse transcriptase expression is increased early in the Barrett's metaplasia, dysplasia, adenocarcinoma sequence

Barrett's esophagus is a multistage polyclonal disease that is associated with the development of adenocarcinoma of the esophagus and esophagogastric junction. Telomerase activation is associated with cellular immortality and carcinogenesis, and increased expression of the telomerase reverse transcriptase catalytic subunit (hTERT) has been used for the early detection of malignant diseases. To identify biomarkers associated with each stage of the Barrett's process, relative mRNA expression levels of hTERT were measured using a quantitative reverse transcription-polymerase chain reaction method (ABI 7700 Sequence Detector (TaqMan system) in Barrett's intestinal metaplasia (n = 14), Barrett's dysplasia (n = 10), Barrett's adenocarcinoma (n = 14), and matching normal squamous esophagus tissues (n = 32). hTERT expression was significantly increased at all stages of Barrett's esophagus, including the intestinal metaplasia stage, compared to normal tissues from patients without cancer (intestinal metaplasia vs. normal esophagus, P <0.0001; dysplasia, P = 0.001; adenocarcinoma, P = 0.007; all Mann-Whitney U test ). hTERT expression levels were significantly higher in adenocarcinoma tissues than in intestinal metaplasia tissues (P = 0.003), and were higher in dysplasia compared with intestinal metaplasia tissues (P = 0.056). hTERT levels were also significantly higher in histologically normal squamous esophagus tissues from cancer patients than in normal esophagus tissues from patients with no cancer (P = 0.013). Very high expression levels ([hTERT x 100: beta-actin] >20) were found only in patients with cancer. These findings suggest that telomerase activation is an important early event in the development of Barrett's esophagus and esophageal adenocarcinoma, that very high telomerase levels may be a clinically useful biomarker for the detection of occult adenocarcinoma, and that a widespread cancer "field" effect is present in the esophagus of patients with Barrett's cancer.

Preoperative paclitaxel and radiotherapy for locally advanced breast cancer: surgical aspects

INTRODUCTION

Approximately 15% of breast cancer patients present with large tumors that involve the skin, the chest wall, or the regional lymph nodes. Multimodality therapy is required, to provide the best chance for long-term survival. We have developed a regimen of paclitaxel, with concomitant radiation, as a primary therapy in patients with locally advanced breast cancer.

METHODS

Eligible patients had locally advanced breast cancer (stage IIB or III). After obtaining informed consent, patients received paclitaxel (30 mg/m2 during 1 hour) twice per week for 8 weeks and radiotherapy to 45 Gy (25 fractions, at 180 cGy/fraction, to the breast and regional nodes). Patients then underwent modified radical mastectomy followed by postoperative polychemotherapy.

RESULTS

Twenty-nine patients were enrolled. Of these, 28 were assessable for clinical response and toxicity, and 27 were assessable for pathological response. Objective clinical response was achieved in 89%. At the time of surgery, 33% had no or minimal microscopic residual disease. Chemoradiation-related acute toxicity was limited; however, surgical complications occurred in 41% of patients.

CONCLUSIONS

Preoperative paclitaxel with radiotherapy is well tolerated and provides significant pathological response, in up to 33% of patients with locally advanced breast cancer, but with a significant postoperative morbidity rate.

Loss of function of Trp53, but not Apc, leads to the development of esophageal adenocarcinoma in mice with jejunoesophageal reflux

INTRODUCTION

APC and TP53 are tumor suppressor genes known to be altered frequently in human esophageal adenocarcinoma (EAC), which arises as a complication of reflux disease. To determine the functional role of these genes in the development of EAC, we have created reflux in mice gene-targeted for either Trp53 or Apc.

METHODS

Wild-type (WT), p53-knockout (Trp53-/-), or Apc-mutated (ApcMin/+) mice were generated in our breeding colony. Total gastrectomy with esophagojejunostomy was performed at 6 weeks of age, creating jejunoesophageal reflux. Unoperated control mice were maintained under identical conditions. Mice were sacrificed at 30 weeks of age. Histology of the esophagus and jejunal anastamosis or gastroesophageal junction was reviewed by a single pathologist blinded to the genotype of the animal.

RESULTS

The esophagus was normal in all of the unoperated mice (6 ApcMin/+, 6 WT, and 6 Trp53-/-). All operated mice (6 ApcMin/+, 12 WT, and 4 Trp53-/-) had esophagitis, with squamous hyperplasia and early focal ulceration. Barrett's metaplasia was identified in 33% of the operated ApcMin/+ (2/6) and 25% of the Trp53-/- (1/4) mice, but not in the WT mice. Of 4 operated Trp53-/- mice, all developed severe dysplasia of the squamous epithelium and 2 (50%) had EAC on histology, although no gross tumors were seen. No severe dysplasia or carcinoma was identified in any of the ApcMin/+ or WT mice.

CONCLUSIONS

Loss of either Trp53 or Apc leads to the development of columnar metaplasia, whereas loss of Trp53, but not Apc, leads to development of cancer in mice with jejunoesophageal reflux.

Nitrosation of uric acid by peroxynitrite. Formation of a vasoactive nitric oxide donor

Peroxynitrite (ONOO-), formed by the reaction between nitric oxide (. NO) and superoxide, has been implicated in the etiology of numerous disease processes. Low molecular weight antioxidants, including uric acid, may minimize ONOO---mediated damage to tissues. The tissue-sparing effects of uric acid are typically attributed to oxidant scavenging; however, little attention has been paid to the biology of the reaction products. In this study, a previously unidentified uric acid derivative was detected in ONOO--treated human plasma. The product of the uric acid/ONOO- reaction resulted in endothelium-independent vasorelaxation of rat thoracic aorta, with an EC50 value in the range of 0.03-0.3 microM. Oxyhemoglobin, a .NO scavenger, completely attenuated detectable .NO release and vascular relaxation. Uric acid plus decomposed ONOO- neither released .NO nor altered vascular reactivity. Electrochemical quantification of .NO confirmed that the uric acid/ONOO- reaction resulted in spontaneous (thiol-independent) and protracted (t1/2 approximately 125 min) release of .NO. Mass spectroscopic analysis indicated that the product was a nitrated uric acid derivative. The uric acid nitration/nitrosation product may play a pivotal role in human pathophysiology by releasing .NO, which could decrease vascular tone, increase tissue blood flow, and thereby constitute a role for uric acid not previously described.

Recurrent secondary hyperparathyroidism after autotransplantation into the sternocleidomastoid muscle: report of a case with fine needle aspiration findings

BACKGROUND

Recurrent hyperparathyroidism may occur following parathyroid autotransplantation due to autogenous function of the muscle-engrafted tissue. Parathyroid lesions are uncommonly diagnosed on cytology.

CASE

A 31-year-old female with chronic renal failure presented with an elevated parathyroid hormone level and a neck mass in the left sternocleidomastoid muscle, the site of a previous parathyroid autograft. Fine needle aspiration of the mass revealed high cellularity, with perivascularly arranged, three-dimensional, branching clusters; individual cells; and naked nuclei exhibiting anisonucleosis. A diagnosis of parathyroid graft hyperplasia was made by fine needle aspiration and subsequently by histopathologic examination.

CONCLUSION

Fine needle aspiration is an effective tool for confirming the presence of parathyroid autograft hyperplasia, thus allowing the correct surgical approach.

Upregulation of xanthine oxidase by lipopolysaccharide, interleukin-1, and hypoxia. Role in acute lung injury

LPS and selected cytokines upregulate xanthine dehydrogenase/xanthine oxidase (XDH/XO) in cellular systems. However, the effect of these factors on in vivo XDH/XO expression, and their contribution to lung injury, are poorly understood. Rats were exposed to normoxia or hypoxia for 24 h after treatment with LPS (1 mg/kg) and IL-1beta (100 microg/kg) or sterile saline. Lungs were then harvested for measurement of XDH/XO enzymatic activity and gene expression, and pulmonary edema was assessed by measurement of the wet/dry lung weight ratio (W/D). Although treatment with LPS + IL-1beta or hypoxia independently produced a 2-fold elevation (p < 0. 05 versus exposure to normoxia and treatment with saline) in lung XDH/XO activity and mRNA, the combination of LPS + IL-1beta and hypoxia caused a 4- and 3.5-fold increase in these values, respectively. XDH/XO protein expression was increased 2-fold by hypoxia alone and 1.3-fold by treatment with LPS + IL-1beta alone or combination treatment. Compared with normoxic lungs, W/D was significantly increased by exposure to hypoxia, LPS + IL-1beta, or combination treatment. This increase was prevented by treatment of the animals with tungsten, which abrogated lung XDH/XO activity. In conclusion, LPS, IL-1beta, and hypoxia significantly upregulate lung XDH/XO expression in vivo. The present data support a role for this enzyme in the pathogenesis of acute lung injury.

Recurrent Zenker's diverticulum: treatment with crycopharyngeal myotomy

Recurrence following treatment of Zenker's diverticulum (ZD) occurs in up to 16 per cent of patients. We have reviewed our experience with cricopharyngeal myotomy (CM) to determine its safety and efficacy in the treatment of recurrent ZD. Eight patients were treated, five with early recurrence (symptoms persisting or recurring within 6 months of their initial surgery) and three with late recurrence. Most patients with early recurrence did not have an adequate CM as part of their initial therapy, suggesting that adequate myotomy is important for early relief of dysphagia. Seven patients underwent CM alone, and one patient underwent CM with diverticulectomy. All patients experienced immediate relief of their dysphagia, with good to excellent results persisting at last follow-up (mean follow-up 53 months). Complications were seen only in the patient who underwent combined myotomy with diverticulectomy. We have found CM alone to be quite safe and effective in the treatment of recurrent ZD.

Preoperative 5-fluorouracil and radiation therapy for locally advanced breast cancer

BACKGROUND

Fifteen percent of breast cancer patients present with large tumors involving skin or chest wall. Often, surgery with primary wound closure is impossible. We used neoadjuvant chemoradiation in locally advanced breast cancer patients, in hopes of increasing resectability.

METHODS

Eligible patients had locally advanced breast cancer deemed unresectable with primary wound closure. Patients received 8 weeks of infusional 5-fluorouracil (5-FU) 200 mg/m2 per day and radiation therapy to 50 Gy. Patients rendered resectable underwent modified radical mastectomy (MRM) followed up by chemotherapy.

RESULTS

Of 30 evaluable patients, 73% had an objective clinical response. All were able to undergo MRM with primary wound closure; 63% had residual disease, 20% had minimal microscopic disease, and 17% had complete pathologic response. Treatment-related toxicity was minimal. Surgical morbidity was not increased.

CONCLUSIONS

Infusional 5-FU with concomitant radiotherapy is well tolerated and effective at producing shrinkage in the majority of patients, converting inoperable breast cancer to easily resectable disease.

High negative appendectomy rates are no longer acceptable

BACKGROUND

A 10% to 20% negative appendectomy rate has been accepted in order to minimize the incidence of perforated appendicitis with its increased morbidity. We reviewed our experience with appendicitis in order to determine the incidence of negative appendectomies and perforation, and the role of delay in diagnosis or treatment.

METHODS

We reviewed 659 appendectomies performed over a 12-month period. Incidental and pediatric appendectomies were excluded.

RESULTS

Seventy-five percent of patients were male and 25% female. Nine percent had negative appendectomies and 28% had perforated appendicitis. Perforated appendicitis resulted in increased morbidity and length of stay. Delay in presentation greater than 12 hours after the onset of symptoms significantly increased the perforation rate. In-hospital delay did not affect perforation rate.

CONCLUSIONS

We have achieved a negative appendectomy rate lower than that in other reported series, while maintaining an acceptable perforation rate. In the majority of patients, perforated appendicitis is a result of late presentation.

Free and protein-associated nitrotyrosine formation following rat liver preservation and transplantation

Nitrotyrosine in human and animal tissues has been associated with pathologic conditions such as atherosclerosis, renal failure, and acute lung disease. In this study, free and protein-associated nitrotyrosine were determined in plasma and tissue samples using a dual-channel electrochemical detection method. Free nitrotyrosine was quantified in acetonitrile-extracted samples while protein-associated nitrotyrosine was determined in proteinase K-digested samples. In human plasma, total nitrotyrosine increased from 2.3 to 4.3 and 13.2 mumol/mol Tyr following addition of 0, 0.5, and 1 mM ONOO-. To determine if nitrotyrosine was produced during ex vivo hypothermic preservation, rat livers were stored in University of Wisconsin solution (UW) for 0, 6, or 8 h and reperfused for 3 h. Total nitro-tyrosine increased 359 and 908% after 6 and 8 h preservation compared to 0 h. To determine if nitrotyrosine was produced in vivo following hepatic ischemia, a rat preservation-transplantation model was utilized in which livers were flushed with cold UW (0-h group) or transplanted following 6 h hypothermic preservation in UW. Free nitrotyrosine increased from 15.7 +/- 0.3 in the 0-h group to 23.6 +/- 2.5 mumol/mol Tyr, 24 h posttransplant of 6-h preserved livers. Protein-associated nitrotyrosine increased from 9.5 +/- 1.1 in the 0-h group to 27.5 +/- 0.7 mumol/mol Tyr in the 6-h preservation-transplantation group. Protein-associated nitrotyrosine provides an integrative determination of nitration. Detection of free and protein-associated nitrotyrosine in biologic samples may allow insight into the role of .NO-derived oxidants in tissue injury associated with various pathologic conditions.

Recurrent secondary hyperparathyroidism. An argument for total parathyroidectomy

OBJECTIVE

To define better the incidence and causes of recurrent secondary hyperparathyroidism.

DESIGN

Review of total parathyroidectomy with autotransplantation in uremic patients and literature review.

SETTING

Two teaching hospitals.

PATIENTS

Nine patients treated for secondary hyperparathyroidism between 1982 and 1993 by a single surgeon.

INTERVENTIONS

Total parathyroidectomy with autotransplantation into the sternocleidomastoid muscle. Recurrence was treated, if necessary, with a graft reduction procedure.

MAIN OUTCOME MEASURES

The symptomatic and biochemical response to initial therapy, morbidity, and mortality, as well as the development of recurrent hypercalcemia.

RESULTS

All patients were normocalcemic after their initial surgery. One patient died postoperatively (mortality, 11%). Three (38%) of the remaining patients developed recurrent hypercalcemia, 2 (25%) requiring reoperation. Of the 2 patients who underwent surgery for recurrence, 1 had an adenoma in the implant and the other had graft hyperplasia.

CONCLUSIONS

Recurrence rates after total parathyroidectomy with autotransplantation are substantial and, given the pathophysiology of secondary hyperparathyroidism, unavoidable in patients with uncorrected renal failure. An argument is made for performing total parathyroidectomy alone in patients with secondary hyperparathyroidism who will not undergo renal transplantation in the near future.

Liver ischemia-reperfusion increases pulmonary permeability in rat: role of circulating xanthine oxidase

Reactive oxygen species play an important role in pathogenesis of a variety of pathological processes, e.g., ischemia-reperfusion, acute viral infections, thermal injury, hepatic diseases, and acute lung injury. Xanthine oxidase (XO) may be a significant source of these cytotoxic oxygen species. We tested the hypothesis that hepatic ischemia-reperfusion releases xanthine dehydrogenase + XO (XDH + XO) into the circulation and that circulating XO damages isolated perfused lung. Isolated liver + lung preparation was perfused with Krebs-Henseleit buffer to minimize confounding effects of circulating neutrophils. In one group, livers were rendered globally ischemic for 2 h and then reperfused (I/R). In another group, livers were pretreated with allopurinol and perfused with buffer containing additional allopurinol (I/R + Allo). After 2 h of ischemia, an isolated lung was connected to liver, and liver + lung preparation was reperfused in series for 15 min. Liver reperfusion was terminated, and lung was recirculated with liver effluent for 45 min. Capillary filtration coefficient (ml.min-1.cmH2O-1.100 g lung dry wt-1) was 2.0 +/- 0.3 and 1.9 +/- 0.4 in control and I/R + Allo lungs, respectively, and 9.0 +/- 1.2 in I/R lungs (P < 0.001). Lung wet-to-dry weight ratio in control and I/R + Allo lungs was 8.6 +/- 0.3 and 9.1 +/- 0.5, respectively, and 14.9 +/- 1.1 in I/R lungs (P < 0.01). Control and I/R + Allo bronchoalveolar lavage protein content was < 1.0 mg/ml compared with 32.6 +/- 8.4 mg/ml in I/R group.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of surgery in the treatment of nonregionally recurrent melanoma

BACKGROUND

Between 1971 and 1989, 144 patients underwent 183 surgical procedures for resection of nonregional metastatic melanoma.

METHODS

Thirty-six patients with subcutaneous or nodal metastases, 46 patients with pulmonary metastases, 17 patients with brain metastases, 19 with gastrointestinal metastases, and 26 patients with miscellaneous sites of metastatic involvement underwent resection.

RESULTS

The overall 5- and 10-year actuarial survival rates were 20% and 14%, respectively. A single postoperative death occurred in a patient operated on for palliative treatment of gastrointestinal metastases.

CONCLUSIONS

Cox regression analysis suggests that patients with a solitary metastasis confined to the subcutaneous, nonregional lymph nodes or lung are most likely to benefit from aggressive surgical intervention. Surgical intervention represents a potentially important modality in the management of selected patients with nonregional metastatic melanoma.

Surgical treatment and chemotherapy for pulmonary metastases from osteosarcoma

Between 1971 and 1991, 247 patients with stage I osteosarcoma were treated at UCLA. Patients were treated in four sequential groups, with group 1 receiving surgery alone, and groups 2 through 4 receiving various adjuvant chemotherapeutic regimens. The incidence of lung metastases in these patients decreased from 92% (group 1) to 31% (group 4), while the proportion of patients undergoing pulmonary resection increased (17% vs 82%). Overall 5-year survival rate among patients with pulmonary metastases increased from 0 in group 1 to 41% (actuarial) in group 4. No clinical factor correlated significantly with outcome using univariate analysis, although there was a trend toward prolonged survival in those with longer disease-free intervals. Adjuvant chemotherapy and resection of pulmonary metastases have transformed a uniformly fatal condition into one with a reasonable expectation of long-term survival.

Prospective evaluation of the use of antigen-specific immune complexes in predicting the development of recurrent melanoma

We previously demonstrated that the antigen-specific immune complexes captured by the monoclonal antibody MAb JSI in a sandwich enzyme-linked immunosorbent assay were associated with recurrent melanoma. To determine the potential use of antigen-specific immune complex analysis in predicting the development of recurrent melanoma, we prospectively analyzed serum obtained from patients with melanoma following surgical treatment. Two hundred fifty-three patients have been followed up for a median of 25 months (range, 17 to 29 months). Seventy-seven patients (30%) have developed recurrent melanoma. Antigen-specific immune complexes correlated with the stage of disease at time of entry into the study. The absence of antigen-specific immune complexes in postoperative serum samples is predictive of a disease-free status. Long-term follow-up will define the false-positive rate of antigen-specific immune complex analysis. Continued refinement of this approach should lead to clinically useful methodology to monitor human melanoma.

Effects of estradiol and tamoxifen on creatine kinase in rodent mammary carcinomas

The effects of altered estrogenic environments on creatine kinase (CK) and adenylate kinase (AK) were studied in two rodent mammary tumor systems, R3230AC and primary 7,12-dimethylbenz(a)anthracene (DMBA)-induced carcinomas, to determine whether response of these enzymes could be related to their hormone dependence. The hormonal perturbations studied were ovariectomy and administration of various doses of estradiol valerate or the antiestrogen tamoxifen. Total CK activity and AK activity were assessed by a spectrophotometric assay followed by electrophoretic separation of the CK isozymes to determine their relative activities. In the ovarian-independent R3230AC tumors, estrogen treatment produced a dose-related decrease in CK activity, whereas CK was not responsive in ovarian-dependent DMBA-induced tumors. Adenylate kinase activity remained unchanged regardless of the hormonal perturbation. Glucose-6-phosphate dehydrogenase and lactate dehydrogenase, which were studied for comparative purposes, were both estrogen responsive. While both estrogenic and antiestrogenic effects on enzyme activities were observed in the DMBA-induced tumors, the effect of tamoxifen in the R3230AC tumors was generally estrogenic. We conclude that the effect of estrogen on CK-BB in DMBA-induced tumors is not sufficient to be used as a biochemical marker of hormone dependence.

Changes in the synthesis and metabolism of prostaglandins by human fetal membranes and decidua at labor

The production of prostaglandins by dispersed cells from human amnion, chorion, and decidua was examined at term before the onset of labor and at spontaneous vaginal delivery. In order to obtain detailed information about relative prostaglandin production rates, the time course of prostaglandin output was examined by incubating the cells for up to 4 hours and measuring the cumulative output of prostaglandin E2, prostaglandin F2 alpha and 13,14-dihydro-15-keto-prostaglandin F2 alpha in the incubation media. The output of all three prostaglandins was low in tissues obtained before the onset of labor. At labor there was an increased production of prostaglandins E2 and F2 alpha in amnion and a small increase in the output of prostaglandin E2, prostaglandin F2 alpha, and 13,14-dihydro-15-keto-prostaglandin F2 alpha in decidua. In contrast, chorionic cells obtained at spontaneous vaginal delivery showed high levels of 13,14-dihydro-15-keto-prostaglandin F2 alpha in the media with no net production of prostaglandin E2 or F2 alpha. These data suggest a high rate of specific in vitro prostaglandin synthesis in amnion and decidua at labor, accompanied by a high rate of prostaglandin metabolism in chorion.

Effect of sialoadenectomy and salivary gland extracts on gastrointestinal mucosal growth and gastrin levels in the rat

We have examined gastrointestinal mucosal growth 30 days after surgical removal of the submandibular-sublingual salivary glands and ligation of the parotid ducts of rats. The rate of [3H]thymidine uptake in vitro as an estimation of DNA synthesis and the content of DNA and RNA were examined in the oxyntic, duodenal and proximal colonic mucosa. DNA synthesis, DNA and RNA content of oxyntic mucosa were reduced in sialoadenectomized rats when compared to sham-sialoadenectomized control animals. There was no change in the degree of [3H]thymidine incorporation or DNA content of the duodenal or colonic mucosa. Intraperitoneal injection of an aqueous extract of the submandibular-sublingual salivary glands of rats (4.0 mg tissue protein in 0.1 M-sodium phosphate buffer administered twice a day for 15 days) increased the rate of DNA synthesis and the total mucosal DNA and RNA content in the oxyntic mucosa. Injections of extracts of spleen or muscle did not produce consistent results. Administration of epidermal growth factor (10 micrograms/kg) or pentagastrin (250 micrograms/kg) resulted in an increase of the level of DNA synthesis observed in the oxyntic mucosa of sialoadenectomized rats. Plasma and antral tissue levels of the trophic hormone, gastrin, were not significantly decreased in sialoadenectomized rats treated with 0.1 M-sodium phosphate-buffered saline. However, treatment with the salivary tissue extract did result in significant reductions in both plasma and tissue levels of gastrin. We conclude that elimination of the major salivary glands in the rat results in a decrease in [3H]thymidine uptake and DNA content of the gastric oxyntic mucosa. These effects are not mediated via a reduction in endogenous levels of the trophic hormone, gastrin. Administration of an aqueous extract of salivary tissue exerted a small but significant trophic influence on the oxyntic mucosa of the rat.

Influence of desalivation on acid secretory output and gastric mucosal integrity in the rat

Exogenous administration of substances extracted from rodent salivary glands may increase the resistance of gastric mucosal barrier to the disruptive actions of ulcerogenic agents and/or reduce acid secretory output. In the present study the influence of desalivation in the rat on acid secretory function and mucosal integrity has been investigated. Experiments were performed on rats 4 wk after removal of the major salivary glands and ligation of the salivary ducts. Intravenous infusion of pentagastrin (0.1--0.4 microgram/kg/min) resulted in an increase in acid output in desalivated rats although the responses was less than that observed in sham-operated controls. Intraluminal instillation of a bile salt solution (5 mM in 150 mM HCl) in control animals resulted in a significant loss of H+ and the luminal appearance of Na+ and K+. The net fluxes of Na+ and K+ were exacerbated in the desalivated group. Furthermore, the mean area of bile salt-induced ulceration was significantly greater in desalivated rats than in the control group. In the absence of bile salt treatment there was no difference in either the transmural ionic fluxes or area of ulceration between the two groups. These results suggests that removal of the major salivary glands in rats decreases the resistance of the gastric mucosa to bile salt-induced damage.