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J C Nesbitt

Publications and source records attributed to J C Nesbitt.

At least 19 recordsLinked to original sources
PubMed1997

The laryngeal mask airway: a new standard for airway evaluation in thoracic surgery.

BACKGROUND: Thoracic surgeons typically perform fiberoptic bronchoscopy (FOB) before thoracotomy, usually on the day of the operation after intubation with a single-lumen endotracheal tube (ETT) and before insertion of a double-lumen ETT. This routine requires two laryngoscopies and two intubations. The laryngeal mask airway (LMA) is an airway device developed in England and approved by the Food and Drug Administration in 1991 for clinical use in the United States. It requires neither mask ventilation nor laryngoscopy and allows FOB visualization of the epiglottis, larynx, and entire trachea. We assessed the LMA as an alternative to a single-lumen ETT for FOB before thoracotomy. METHODS: Through prospective assessment, 50 patients underwent FOB after insertion of an LMA before thoracotomy. Pulse rate, blood pressure, ease of insertion of the LMA, quality of FOB, and complications of LMA insertion were assessed. RESULTS: During LMA insertion, blood pressure and pulse rate increased less than 5% from baseline in all patients. The LMA was inserted successfully in all patients within 10 seconds. No complications occurred as a result of LMA insertion. CONCLUSIONS: Insertion of the LMA causes minimal hemodynamic response. From the time of induction of general anesthesia, insertion of the LMA is quick, simple, and safe and eliminates the need for endotracheal intubation with a single-lumen ETT before double-lumen tube insertion. The LMA, in contrast to the ETT, allows a complete survey of the larynx and trachea. The LMA is autoclavable, reusable, and cost effective. Therefore, in patients who require FOB immediately before thoracotomy, LMA use should be the standard for airway evaluation.

Bronchoscopy↗
PubMed1997

Surgical management of renal cell carcinoma with inferior vena cava tumor thrombus.

BACKGROUND: The optimal management of patients with renal cell carcinoma with inferior vena cava tumor thrombus remains unresolved. Traditional approaches have included resection with or without the use of cardiopulmonary bypass. Chemotherapy has played a minor role except for biotherapeutic agents used for metastatic disease. METHODS: From January 1989 to January 1996, 37 patients with renal cell carcinoma and inferior vena cava tumor thrombus underwent surgical resection. The 27 men and 10 women had a median age of 57 years (range, 29 to 78 years). Thirty-six patients presented with symptoms; 21 had hematuria. Distant metastases were present in 12 patients. Tumor thrombi extended to the infrahepatic inferior vena cava (n = 16), the intrahepatic inferior vena cava (n = 16), the suprahepatic inferior vena cava (n = 3), and into the right atrium (n = 2). All tumors were resected by inferior vena cava isolation and, when necessary, extended hepatic mobilization and Pringle maneuver, with primary or patch closure of the vena cavotomy. Cardiopulmonary bypass was necessary in only 2 patients with intraatrial thrombus. RESULTS: Complications occurred in 11 patients, and 1 patient died 2 days postoperatively of a myocardial infarction (mortality, 2.7%). Twenty patients are alive; overall 2- and 5-year survival rates were 61.7% and 33.6%, respectively. For patients without lymph node or distant metastases (stage IIIa), 2- and 5-year survival rates were 74% and 45%, respectively. The presence of distant metastatic disease (stage IV) at the time of operation did not have a significant adverse effect on survival, as reflected by 2- and 5-year survival rates of 62.5% and 31.3%, respectively. Lymph node metastases (stage IIIc) adversely affected survival as there were no long-term survivors. CONCLUSIONS: Resection of an intracaval tumor thrombus arising from renal cell carcinoma can be performed safely and can result in prolonged survival even in the presence of metastatic disease. In our experience, extracorporeal circulatory support was required only when the tumor thrombus extended into the heart.

Adult↗
PubMed1996

Retrovirus-mediated wild-type p53 gene transfer to tumors of patients with lung cancer.

A retroviral vector containing the wild-type p53 gene under control of a beta-actin promoter was produced to mediate transfer of wild-type p53 into human non-small cell lung cancers by direct injection. Nine patients whose conventional treatments failed were entered into the study. No clinically significant vector-related toxic effects were noted up to five months after treatment. In situ hybridization and DNA polymerase chain reaction showed vector-p53 sequences in posttreatment biopsies. Apoptosis (programmed cell death) was more frequent in posttreatment biopsies than in pretreatment biopsies. Tumor regression was noted in three patients, and tumor growth stabilized in three other patients.

Aged↗
PubMed1996

Expandable stents.

Expandable metallic stents are effective in selected patients with malignant or benign airway stenoses. When used for malignant lesions, the primary purpose of the stent is to improve the quality of life; stents are usually chosen for palliation of symptoms in recognition of the low likelihood of success for other therapy. For patients with benign stenoses, the stents provide a permanent source of structural support to alleviate the narrowed segment. The advantages of the expandable metallic stents are as follows: (1) they can be inserted through an endotracheal tube or under local anesthesia with relative simplicity under fluoroscopic guidance; (2) they do not impair the drainage of sputum because ciliary movement is not interrupted; (3) over a period of a few weeks, the meshwork is gradually covered with mucosa as the stent becomes incorporated into the airway wall; (4) ventilation usually is not impaired if the metallic mesh stent covers another nonstenosed bronchus, because the interstices of the stent are nonobstructive; and (5) they are dynamic and continue to expand over time, particularly if concurrent treatment achieves an effect on the lesion that caused stenosis. Disadvantages of the expandable stent include (1) they often are only temporarily effective for tracheobronchial stenosis due to intraluminal tumor or granulation tissue, both of which can grow between the wires; (2) they are considered permanent stents because removal is difficult; and (3) they can be poorly positioned during placement or can become displaced by progressive migration after placement, and they cannot be repositioned. A relative contraindication to insertion is an inflammatory process or infection that can predispose to granulation formation, particularly at the points of maximal contact pressure of the stent to the airway mucosa. In the presence of inflammation, it may be better to use a silicone prosthesis until the inflammatory process subsides and fibrosis occurs. Granulation tissue is less likely to occur in areas of established scar than in areas of acute inflammation. In circumstances in which it is essential that a stent remain only temporarily, an expandable stent should not be inserted in favor of a silicone stent, which can be removed. In the future, expandable stents may have silicone coverings or may be constructed of materials that facilitate removal. Until that time, expandable stents should be considered permanent and nonremovable. Subtle differences exist among the available stents. Standard is low-profile expandable construction from wire mesh. A relatively minor difference is the slightly wider expansibility of the Gianturco stent, a quality that makes it the best suited of the three stents for lesions that involve tracheomalacia. Perhaps the only major difference between the Wallstent and the Gianturco and Palmaz stents is its better ability to conform to tortuous lesions. In an acutely angled stricture, a Wallstent offers a better opportunity for successful placement than other stents. The filamentous meshwork of the Wallstent allows it to bend and conform better to distorted airways. The Gianturco and Palmaz stents have little longitudinal elasticity, which makes them less effective in a tortuous or highly angulated airway stenosis. Expandable stents have demonstrated their efficacy and exposed their limitations in the treatment of airway stenoses. Refinements in design should help to lessen specific disadvantages and problems. Covered expandable stents, a realistic prospect, have specific advantages over standard expandable stents; they will be removable and prevent tumor ingrowth. Current investigative work with such prostheses for the vascular system may provide the foundation for their investigative use in the airway. In essence, two categories of expandable stents are evolving, covered and uncovered, each having unique features adaptable to the specific clinical needs.

Bronchial Diseases↗
PubMed1996

Retinoic acid receptor- and retinoid X receptor-selective retinoids activate signaling pathways that converge on AP-1 and inhibit squamous differentiation in human bronchial epithelial cells.

Human bronchial epithelial (HBE) cells undergo squamous differentiation in response to a variety of conditions in tissue culture, and retinoid treatment has been shown to reverse this process. Retinoids mediate their effects through the retinoic acid and retinoid X nuclear receptors (RAR and RXR, respectively), which form RAR-RXR heterodimers, RXR homodimers, and heterodimers of RXR and certain orphan receptors. These receptor dimers bind to distinct response elements, activating separate pathways. In this study, we investigated the roles of RAR and RXR signaling pathways in the inhibition of HBE squamous differentiation. After induction of squamous differentiation by confluent growth, HBE cells were treated with retinoids that selectively activate RARs (E-4-[2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthaienyl)-1- propenyl] benzoic acid), RXRs (4-[1-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)ethenyl]benzoic acid), or both RARs and RXRs (9-c/s retinoic acid). These retinoids inhibited the mRNA expression of the squamous differentiation markers transglutaminase type I, involucrin, keratin 5, and keratin 13, suggesting that inhibition of HBE squamous differentiation could be mediated by activation of either RAR or RXR signaling pathways. We examined the role of AP-1 as a potential effector of these retinoid pathways. AP-1 transcriptional activity was reduced markedly by these retinoids, and a concomitant, but proportionally smaller, reduction in AP-1 DNA binding was observed. Furthermore, treatment of squamous HBE cells with the retinoid SR11238, which inhibited AP-1 without activating retinoid receptor transcriptional properties, reduced the expression of transglutaminase type I and involucrin. These findings support the hypothesis that, in HBE cells, RAR and RXR signaling pathways inhibit AP-1 transcriptional activity, and this contributes to retinoid-induced reversal of HBE squamous differentiation.

Alitretinoin↗
PubMed1995

Retinoid refractoriness occurs during lung carcinogenesis despite functional retinoid receptors.

Retinoids have demonstrated activity in the prevention of second primary tumors in patients with non-small cell lung cancer (NSCLC). They also contribute to the normal growth and differentiation of human bronchial epithelial (HBE) cells. Because retinoids mediate their actions through retinoid nuclear receptors (RARs and RXRs), aberrant signaling through retinoid receptors could contribute to lung carcinogenesis. Using a lung carcinogenesis model consisting of normal, premalignant, and malignant HBE cells, we examined all-trans retinoic acid (t-RA)-induced changes in cellular growth. These studies revealed that t-RA treatment inhibited the growth of normal HBE cells, but premalignant and malignant HBE cells were relatively resistant to t-RA. Coincident with the development of retinoid refractoriness, basal expression of the retinoic acid nuclear receptor beta (RAR-beta) increased. Analysis of receptor function by gel shift and transient transfection assays of normal, premalignant, and malignant HBE cells demonstrated that receptor-DNA binding and transcriptional activation properties were intact in the t-RA-refractory malignant HBE cells. To compare these findings to NSCLCs in patients, we investigated retinoid receptor expression in NSCLC biopsies. A subset of the tumors expressed RAR-beta, reflecting the RAR-beta expression observed in the malignant HBE cells in culture. These findings demonstrate that retinoid receptor function was intact in the t-RA-refractory malignant HBE cell line, suggesting that the defect in retinoid signaling in this lung carcinogenesis model is not intrinsic to the retinoid receptors.

Animals↗
PubMed1995

Malignant pleural mesothelioma after radiation therapy for breast cancer. A report of two additional patients.

BACKGROUND: Malignant pleural mesotheliomas (MPMs) are rare tumors that usually have a fatal outcome. The association of these tumors with asbestos exposure is well established. Induction of malignant mesothelioma by nonasbestos-related causes also has been reported in the literature, although the number of documented cases is extremely small. Two additional patients with malignant pleural mesothelioma many years after radiotherapy for breast cancer are reported. METHODS: The observations as reported in the literature on the involvement of radiation in the development of MPMs are reviewed and compared with the authors' clinical experience. In a retrospective random review, 1000 patients who received thoracic irradiation at M. D. Anderson Cancer Center were studied for histologic and radiographic evidence of MPM. The selection criteria included the development of a unilateral pleural effusion years after successful treatment with thoracic irradiation for a proven malignancy. Patients with a history compatible with asbestos exposure were excluded from the review. RESULTS: There have been only three previous cases of documented MPM associated with thoracic irradiation reported in the English literature. A review of the experience at our institution has demonstrated three patients with radiation-induced MPM. One patient has been reported elsewhere. Details of the other two patients are discussed in this paper. CONCLUSIONS: Nonasbestos-related causes of MPMs are rare. The additional two patients lend added support to the association between thoracic irradiation and the development of MPM. The development of a unilateral pleural effusion occurring years after successful treatment of a proven malignancy with thoracic irradiation should alert the clinician to the possibility of MPM.

Aged↗
PubMed1995

Tumor implants after thoracoscopic resection of a metastatic sarcoma.

Tumor implantation after video-assisted thoracic operations is rare. We describe the case of a 61-year-old woman who underwent an apparently uneventful thoracoscopic resection of a solitary pulmonary metastasis from a primary limb sarcoma. Within 3 months, extensive trocar and diaphragmatic implants developed that required an extensive en bloc resection of her chest wall, diaphragm, and lung. Because of the aggressive biologic behavior of sarcomas and their potential to grow in surgical tracts, concern is raised about the advisability of using video-assisted thoracic surgical techniques in the management of these tumors.

Female↗
PubMed1995

Survival in early-stage non-small cell lung cancer.

The duration of survival in early-stage lung cancer (stages I and II) varies between reports in the literature. Several reasons account for this: patient population heterogeneity, inconsistent staging, anatomic variability, dissimilar tumor morphology, and unpredictable tumor biology. This report addresses some of the issues in early-stage non-small cell lung cancer that relate to variability between estimates of survival in end stage reporting. We review several large series since the introduction of the International Staging System in 1986 and other selected, contemporary reports that address end results in patients with pathologic stage I or stage II lung cancer. Overall survival for patients with pathologic stage I disease is 64.6% (range, 55% to 72%) and 41.2% for patients with stage II disease (range, 29% to 51%). Reducing morphologic differences by placing patients in groups based on the TNM subset and refinement in categorization by matching TNM subsets based on histology and other factors can improve considerably homogeneity and enhance prognostic predictability. The development of more accurate measures for predicting prognosis may serve to clarify the roles of primary and adjuvant treatment, particularly in those patients with early-stage disease associated with poor prognostic factors in whom the potential for long-term survival is reduced.

Biomarkers, Tumor↗
PubMed1995

Resection of sternal tumors: extent, reconstruction, and survival.

BACKGROUND: Resection of sternal tumors may be tailored to the patient and the location of the malignancy. METHODS: We reviewed our results of sternectomy (typically 5-cm margins) performed in 30 patients over a 10-year period. RESULTS: Thirteen patients had primary sternal sarcoma (six chondrosarcoma, five osteosarcoma, two other); 10 patients had local recurrence from breast cancer; 4 patients had metastases; 3 patients had other (two osteoradionecrosis, one malignant fibrous histiocytoma). Morbidity occurred in 8 patients (26.7%): wound dehiscence, 2; wound infection, 1; hemorrhage, 1; pneumonia, 1; prolonged air leak, 1; empyema, 1; and bronchopleural fistula, 1. One patient, with multiple metastases, died from adult respiratory distress syndrome on day 25 (overall mortality, 3.3%; 1 of 30). The area of reconstruction ranged from 35 to 264 cm2. The technique of reconstruction included muscle flap alone in 13 patients; muscle flap and mesh, 9; muscle flap and rigid prosthesis (Marlex methylmethacrylate), 7; or other, 1 patient. Nineteen patients (63%) were extubated within 24 hours after operation. Median intensive care unit stay was 2 days; median hospitalization, 6 days. Late local recurrence after resection occurred in 6 patients; 4 from breast cancer (3 patients had concurrent distant metastases). Five-year actuarial survival after primary tumor resection was 73% and 33% after resection of recurrent breast cancer (median, 21 months). CONCLUSIONS: Partial sternectomy may be performed for primary sternal tumors with short hospitalization and good local control. Wider local excision or total sternectomy may minimize local re-recurrence of breast carcinoma to the sternum.

Actuarial Analysis↗
PubMed1995

Is follow-up of lung cancer patients after resection medically indicated and cost-effective?

BACKGROUND: There are no guidelines for the appropriate follow-up of patients after pulmonary resection for lung cancer. METHODS: Three-hundred fifty-eight consecutive patients who had undergone complete resections of non-small cell lung cancer between 1987 and 1991 were evaluated for tumor recurrence and development of second primary tumors. Recurrences were categorized by site (local or distant), mode of presentation (symptomatic or asymptomatic), treatment given (curative intent or palliative), and duration of overall survival. RESULTS: Recurrences developed in 135 patients (local only, 32; local and distant, 13; and distant only, 90). Of these, 102 were symptomatic and 33 were asymptomatic (most diagnosed by screening chest roentgenogram). Forty patients received treatment with curative intent (operation or radiation therapy > 50 Gy) and 95 were treated palliatively. The median survival duration from time of recurrence was 8.0 months for symptomatic patients and 16.6 months for asymptomatic patients (p = 0.008). Multivariate analysis shows that disease-free interval (greater than 12 months or less than or equal to 12 months) was the most important variable in predicting survival after recurrence and that mode of presentation, site of recurrence, initial stage, and histologic type did not significantly affect survival. New primary tumors developed in 35 patients. CONCLUSIONS: Although detection of asymptomatic recurrences gives a lead time bias of 8 to 10 months, mode of treatment and overall survival duration are not greatly affected by this earlier detection. Disease-free interval appears to be the most important determinant of survival. Screening for asymptomatic recurrences in patients who have had lung cancer is unlikely to be cost-effective. Frequent follow-up and extensive radiologic evaluation of patients after operation for lung cancer are probably unnecessary.

Adult↗
PubMed1994

Management of tracheal and bronchial stenoses with the Gianturco stent.

Thirty-six cancer patients with symptomatic tracheobronchial stenoses received Gianturco tracheobronchial stents over a 9-year period. Symptoms improved in 28 patients (78%). The overall median survival was 1 month 3 weeks (range, 4 days to 35 months). The median survival for patients who showed improvement after receiving stents was 3 months compared with 1 week for those who did not respond. Complications were minimal. The Gianturco stent may palliate symptoms of tracheobronchial compression in selected cancer patients.

Adult↗
PubMed1994

Resection of lung cancer is justified in high-risk patients selected by exercise oxygen consumption.

The medical criteria for inoperability have been difficult to define in patients with lung cancer. Sixty-six patients with non-small cell lung cancer and radiographically resectable lesions were evaluated prospectively in a clinical trial. The patients were considered by cardiac or pulmonary criteria to be high risk for pulmonary resection. If exercise testing revealed a peak oxygen uptake of 15 mL.kg-1.min-1 or greater, the patient was offered surgical treatment. Of the 20 procedures performed, nine were lobectomies, two were bilobectomies, and nine were wedge or segmental resections. All patients were extubated within 24 hours and discharged within 22 days after operation (median time to discharge, 8 days). There were no deaths, and complications occurred in 8 (40%) of the 20 patients. Five patients whose peak oxygen uptake was lower than 15 mL.kg-1.min-1 also underwent surgical intervention; there was one death. Thirty-four patients whose peak oxygen uptake was less than 15 mL.kg-1.min-1 and 7 who declined operation underwent radiation therapy alone (35 patients) or radiation therapy and chemotherapy (6 patients). There were no treatment-related deaths, and the morbidity rate was 12% (5/41). The median duration of survival was 48 +/- 4.3 months for the patients treated surgically and 17 +/- 2.7 months for those treated medically (p = 0.0014). We conclude that a subgroup of patients who would be considered to have inoperable disease by traditional medical criteria can be selected for operation on the basis of oxygen consumption exercise testing. There is a striking survival benefit to an aggressive surgical approach in these patients.

Adenocarcinoma↗
PubMed1994

Lung tumor resection does not affect debrisoquine metabolism.

Some authors have reported an association of extensive metabolism of debrisoquine with increased lung cancer risk, although others have found no association. Debrisoquine metabolism is controlled by a cytochrome P-450 isozyme encoded at the CYP2D6 locus, which is inducible by antipyrine and rifampicin. Because lung tumors may produce a variety of humoral substances, we wanted to determine whether the tumor induced debrisoquine metabolism. As part of a case-control study of lung cancer, debrisoquine metabolism was measured in patients with histologically confirmed non-small cell lung cancer before and after surgical resection with curative intent. One hundred four incident patients with curative intent. One hundred four incident patients with pathological stage I, II, or IIIA non-small cell lung cancer took debrisoquine (10 mg) orally at 10 p.m. and collected the subsequent 8-h urine both before and after surgery. We compared the values of the metabolic ratio, which is the percentage of the dose excreted as debrisoquine to the percentage of the dose excreted as the principal metabolite. The pre- and postoperative metabolic ratios were highly correlated (Pearson correlation coefficient = 0.96), and did not differ in value significantly (P = 0.88). Using traditional cutpoints (metabolic ratio, 1.0 and 12.6) to categorize the three metabolic phenotypes, the preoperative and postoperative phenotypes were well correlated (kappa = 0.78). These results show that the ability to metabolize debrisoquine is not induced by the presence of a primary lung tumor.

Carcinoma, Non-Small-Cell Lung↗
PubMed1987

Surgical management of esophageal perforation.

The recognition and management of esophageal perforation remain a problem. Diagnostic and treatment delays are common, and controversy continues regarding approaches to surgical intervention. Overall survival has increased with improved adjunctive modalities; however, morbidity and mortality remain high. A total of 115 consecutive cases of nonmalignant esophageal perforation were reviewed. There were 69 thoracic, 27 cervical, and 19 abdominal perforations. Etiology of the perforations was iatrogenic in 65 patients, traumatic in 28, and spontaneous perforation in 22. Symptoms included pain (71%), fever (51%), dyspnea (24%), and crepitus (22%). Contrast roentgenography was used in 78 patients and demonstrated the perforation in all but two patients. All but 20 patients had operations. In the last decade, the survival rate was 11.4 per cent for patients treated within 24 hours of perforation. Survival significantly improved in the last 10 years because of hyperalimentation, cardiopulmonary monitoring, and better antibiotic coverage. Treatment of choice is primary closure with drainage, regardless of the duration of the perforation. In selected patients who have cervical esophageal perforation, nonoperative management has a role.

Esophageal Diseases↗
PubMed1986

A new model to study acute and chronic renal failure.

Many models have been developed to study renal function following injury. Two types of studies have evolved: acute--to define the acute renal injury and chronic--to determine the pattern of recovery. Current models allow either study alone to be performed, but they lack the flexibility to combine the studies. In this study of renal ischemia, a model was designed which solved this problem. The authors constructed a model for performing a unilateral nephrectomy and episiotomy on female dogs. Catheters were placed in the renal vein, vena cava, and aorta, and a renal artery flow cuff was applied. The catheters and wires were buried in a subcutaneous pocket and were exteriorized after a recovery of several weeks. The episiotomy allowed easy intermittent Foley catheterization. With the animals awake and in a harness, parameters of renal function were measured: renal extraction, filtration fraction, fractional excretion, osmolar clearance, and free water clearance. Glomerular filtration rate and renal plasma flow were calculated by inulin and paramino hippurate clearances. The animals were studied in diuretic and antidiuretic states. In addition, renal artery flow was determined by the Doppler flow cuff. All parameters were determined every half hour in the acute setting, then every day in the chronic setting. The model was easily reproducible and functioned well in the authors' renal ischemia studies. Initial experiments with 1 hour of warm ischemia produced a greater than 50 per cent reduction in GFR acutely. Chronic studies showed a GFR with a return toward normal. All model construction purposes and plans were met.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1985

Colorectal carcinoma in pregnancy.

Colorectal carcinoma in pregnancy is rare. The symptoms frequently are masked by the symptoms associated with normal pregnancy, resulting in delayed diagnosis. Based on our experience with five patients and review of the literature, we developed a management regimen that takes an aggressive approach to tumor excision, yet maintains the pregnancy and fertility if possible. The prognosis is poor for most patients because the stage of the tumor is usually advanced at the time of diagnosis. The key to improved survival, as with all cancers, is early diagnosis and treatment.

Adult↗