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R J Downey

Publications and source records attributed to R J Downey.

At least 37 records · Page 2Linked to original sources
PubMed1998

Extramedullary hematopoiesis mimicking metastatic lung carcinoma.

Extramedullary hematopoiesis is a rare condition defined as the appearance of hematopoietic elements outside of the bone marrow, which occurs primarily in patients with chronic myeloproliferative disorders or congenital hemolytic anemias. We report a patient who presented with a left lower lobe lung carcinoma and right paravertebral and left pleural masses, initially thought most consistent radiographically with inoperable metastatic disease, until biopsies of the paravertebral and pleural masses established the presence of extramedullary hematopoiesis. The left lower lobe neoplasm was subsequently resected uneventfully.

Adenocarcinoma↗
PubMed1998

Pulmonary metastasectomy for testicular germ cell tumors: a 28-year experience.

BACKGROUND: The role of surgery in patients with pulmonary metastatic germ cell tumors has been evolving since the 1970s. To evaluate the results of pulmonary resection, we reviewed our 28-year experience. METHODS: Between July 1967 and May 1995, 157 patients with testicular germ cell tumors underwent pulmonary resections for suspected metastases. Their clinical and pathological data were reviewed. Kaplan-Meier and Cox regression models were used to analyze prognostic factors for survival after resection of metastatic disease. RESULTS: All patients were male with median age of 27 years (range 15-65). Complete resection was accomplished in 155 (99%) patients. Viable carcinoma was present in 44% (70) of the patients. Forty-one (26%) patients had metastases to other sites after pulmonary metastasectomy. The overall actuarial survival 5 years after pulmonary resection was 68% for the entire group and 82% for patients diagnosed after 1985. On multivariate analysis, the adverse prognostic factors were metastases to nonpulmonary visceral sites (p = 0.0069) and the presence of viable carcinoma in the resected specimen (p < 0.0001). CONCLUSIONS: With current chemotherapy regimens, almost 85% of the patients with testicular germ cell tumors undergoing complete resection of their pulmonary metastases can be expected to achieve long-term survival.

Adolescent↗
PubMed1998

Thymic carcinoma: current staging does not predict prognosis.

BACKGROUND: Thymic carcinomas are currently staged by Masaoka classification, a staging system for thymomas. We retrospectively evaluated surgical patients with thymic carcinoma to determine prognostic factors and to evaluate the usefulness of Masaoka staging in this disease. METHODS: Our computerized tumor registry yielded 118 patients with thymoma. Review of pathologic material revealed 43 cases of thymic carcinoma. Collection of data was by review of hospital and physician charts and telephone contact with patients. Analysis of prognostic factors was performed in patients undergoing complete resection by the method of Kaplan-Meier and Cox proportional hazards regression. RESULTS: Between 1949 and 1993, 43 patients underwent surgery for thymic carcinoma. Overall survival was 65% at 5 years and 35% at 10 years. Overall recurrence was 65% at 5 years and 75% at 10 years. On univariate analysis, survival was not dependent on age, sex, tumor size, or Masaoka stage but was dependent on innominate vessel invasion. By multivariate analysis, survival was dependent only on innominate vessel invasion. CONCLUSIONS: Patients with thymic carcinoma have a high rate of recurrence. Tumor invasion of the innominate vessels is associated with a particularly poor prognosis. Although Masaoka staging is useful in staging patients with thymoma, it does not appear to predict outcome for patients with thymic carcinoma.

Adult↗
PubMed1998

Proposed revision of the staging classification for esophageal cancer.

OBJECTIVES: This study analyzed survival with respect to lymph node involvement to develop a new staging system for patients with esophageal cancer that accurately reflects prognosis. METHODS: The records of patients undergoing resection of primary esophageal cancer from 1989 to 1993 were reviewed. The data collected included patient age and sex, tumor histologic characteristics and location, the use of preoperative or postoperative radiation and chemotherapy, the type of resection, the depth of tumor invasion, the number and location of benign and malignant lymph nodes in the resected specimen, the disease status at last follow-up, and the first site of relapse. With an anatomically specific lymph node map, tumors designated in the current American Joint Committee on Cancer system as M1 because of extensive lymph node metastases were reclassified as N2, reserving the M1 category for visceral metastases. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were assessed by log-rank and Cox regression analyses. RESULTS: There were 216 patients (159 men, 57 women) with a median age of 63.5 years. Adenocarcinoma of the distal esophagus or gastroesophageal junction was the most common tumor (127 patients, 59%) and Ivor Lewis esophagogastrectomy was the most frequently performed operation. Both lymph node location (N1 versus N2) and number (0 vs 1 to 3 vs 4 or more) significantly influenced survival. CONCLUSIONS: A new staging system that adds an N2 M0 descriptor and reclassifies stage groupings reflects prognosis more accurately than does the current American Joint Committee on Cancer staging system. The number of positive lymph nodes is also an important stratification factor.

Adenocarcinoma↗
PubMed1998

Complications after video-assisted thoracic surgery.

Video-assisted thoracic surgery (VATS) procedures have been adopted widely and rapidly for the treatment of a wide range of benign and malignant thoracic disorders. To date, there is only incomplete information available about the complications associated with these techniques. In this article, the available literature addressing the types and incidence of postoperative complications associated with VATS procedures is reviewed, as are the problems of incisional pain, alterations in respiratory function, and dissemination of malignancy following manipulation of tumors by VATS techniques.

Endoscopy↗
PubMed1997

Effects of diltiazem versus digoxin on dysrhythmias and cardiac function after pneumonectomy.

BACKGROUND: This prospective study was designed to determine whether diltiazem is superior to digoxin for the prophylaxis of supraventricular dysrhythmias (SVD) after pneumonectomy or extrapleural pneumonectomy (EPP) and to assess the influence of these drugs on perioperative cardiac function. METHODS: Seventy consecutive patients without previous SVD were randomly allocated immediately after pneumonectomy or EPP to receive diltiazem (n = 35) or digoxin (n = 35). Diltiazem-treated patients received a slow intravenous loading dose of 20 mg, followed by 10 mg intravenously every 4 hours for 24 to 36 hours, then 180 to 240 mg orally daily for 1 month. Digoxin-treated patients received a 1-mg intravenous loading in the first 24 to 36 hours, then 0.125 to 0.25 mg orally daily for 1 month. A concurrent prospective cohort of 40 patients without previous SVD, who did not participate in the study and underwent pneumonectomy or EPP without prophylaxis, served as a comparison group for SVD occurrence. Serial Doppler echocardiograms were performed to assess cardiac function and all patients were continuously monitored with Holter recorders for 3 days. Data were analyzed by intent-to-treat. RESULTS: In patients undergoing standard or intrapericardial pneumonectomy, diltiazem prevented the overall incidence of postoperative SVD when compared with digoxin, 0 of 21 patients versus 8 of 25 patients, respectively, p < 0.005. When EPP patients were included in the analysis, diltiazem decreased the incidence of all SVD from 11 of 35 patients (31%) to 5 of 35 patients (14%) when compared with digoxin, p = 0.09. Digoxin-treated patients had a similar incidence of all SVD (31%) as concurrent controls (11 of 40 patients [28%]). The two treated groups did not differ in right or left atrial size, left ventricular ejection fraction, or right heart pressure. When all patients were combined, those in whom SVD developed were significantly older (65 +/- 12 years versus 55 +/- 11 years, p = 0.004) and had a longer median hospital stay (9 versus 6 days, p = 0.03), when compared with those in whom SVD did not develop, respectively. The subset of patients undergoing EPP had a greater incidence of atrial fibrillation and electrocardiographic changes suggestive of postoperative pericarditis than all other pneumonectomy patients. CONCLUSIONS: Diltiazem was both safe and more effective than digoxin in reducing the overall incidence of SVD after standard or intrapericardial pneumonectomy. Digoxin therapy had no effect on the incidence of postoperative SVD and is not recommended for prophylaxis of SVD. Dysrhythmias after pneumonectomy or EPP occur in older patients and are associated with a greater length of hospital stay.

Aged↗
PubMed1996

Role of video-assisted thoracic surgery in the treatment of pulmonary metastases: results of a prospective trial.

BACKGROUND: A retrospective review revealed a 42% error rate between computed tomographic scan reports and thoracotomy findings; therefore, a prospective study was designed to compare the value of computed tomographic scans, video-assisted thoracoscopic exploration, and open thoracotomy in the management of pulmonary metastases. METHODS: Eligibility included any patient with only one or two ipsilateral pulmonary metastases identified on computed tomographic scan who was being considered for surgical resection. Initially video-assisted thoracic surgery was performed and all lesions identified were resected. A thoracotomy adequate for complete lung palpation was then carried out and any additional lesions found were removed. RESULTS: Eighteen patients of a planned 50 were treated before closure of the study. Four patients (22%) had no additional lesions found at thoracotomy. The primary sites of tumor were colon (10), breast (3), and one patient each skin (squamous), cervix, kidney, melanoma, and sarcoma. Four patients (22%) did have additional lesions at thoracotomy, which were benign. In the remaining 10 patients (56%) additional malignant lesions were found at thoracotomy after video-assisted thoracoscopic exploration. After 18 patients were entered, analysis of the early results disclosed a 56% failure rate of a computed tomographic scan and video-assisted thoracic surgery to detect all lesions. Being within the 95% confidence interval (32% to 78%), the study was abandoned. CONCLUSIONS: We conclude that video-assisted thoracic surgery should be used only as a diagnostic tool in managing lung metastasis. A thoracotomy is required to achieve complete resection, which is the major survival prognosticator for satisfactory long-term results.

Breast Neoplasms↗
PubMed1996

Dissemination of malignant tumors after video-assisted thoracic surgery: a report of twenty-one cases. The Video-Assisted Thoracic Surgery Study Group.

Video-assisted thoracic surgical techniques are widely used for biopsy and resection of thoracic tumors, but studies of long-term outcomes have not been reported. Dissemination of tumor by these techniques is a potential hazard. Therefore we surveyed the surgical members of the Video-Assisted Thoracic Surgery Study Group to determine whether tumor implants thought to be directly related to video-assisted techniques had occurred. Surgeons reported 21 cases. The sites of recurrence were the incision (n = 14), pulmonary staple line (n = 2), pleura (n = 2), both staple line and incision (n = 1), both pleura and incision (n = 1), and both pleura and staple line (n = 1). Review of these cases illustrates the pitfalls of present video-assisted techniques for malignant tumors of the thorax.

Adult↗
PubMed1996

Predictors of survival in malignant tumors of the sternum.

From 1930 to 1994, 54 patients with primary malignant tumors of the sternum were seen. Fifty patients were first seen with a mass, and one half of them also had pain in the sternal region. Two patients had no symptoms at presentation. Among 39 solid tumors were 26 chondrosarcomas, 10 osteosarcomas, 1 fibrosarcoma, 1 angiosarcoma, and 1 malignant fibrous histiocytoma. Of these, 25 were low-grade and 14 were high-grade tumors. Among 15 small cell tumors were 8 plasmacytomas, 6 malignant lymphomas, and 1 Ewing's sarcoma. Partial or subtotal sternectomy was done in 37 patients and total sternectomy in 3. Of the remaining 14 patients, 3 had local excision; 10 had external radiation or chemotherapy without operation, or both; and 1 had no treatment. All but one patient treated by wide resection (N = 40) had some form of skeletal reconstruction of the chest wall defect. Thirty-one (78%) underwent repair with Marlex mesh, and in 25 this was combined with methyl methacrylate. The skin edges were closed per primum in 32 patients; 8 required muscle, omentum, or skin flaps. Resection in chondrosarcomas yielded a 5-year survival (Kaplan-Meier) of 80% (median follow-up, 17 years). The 5-year survival in osteosarcomas was 14%. Resection was curative in 64% of low-grade sarcomas but in only 7% of high-grade sarcomas. In small cell tumors, resection and radiation were helpful for local control; all failures were a result of distant metastases. We conclude that primary sarcomas of the sternum though uncommon are potentially curable by wide surgical excision. With rigid prostheses to repair the skeletal defects, the surgical complication rates are low. Overall survival after complete surgical resection is related to tumor histologic type and grade.

Bone Cements↗
PubMed1995

Management strategies for pulmonary vein thrombosis following single lung transplantation.

Pulmonary vein thrombosis following lung transplantation is an infrequently reported and often fatal vascular complication. Two cases of early pulmonary vein thrombosis following single lung transplantation are described. Both patients underwent surgical thrombectomy and anastomotic reconstruction following institution of cardiopulmonary bypass, but died of multiorgan failure within 5 days of diagnosis. The efficacy of transesophageal echocardiography as a diagnostic modality, as well as medical and surgical management strategies for thrombectomy, are discussed.

Adult↗
PubMed1995

Mediastinal parathyroid cysts.

OBJECTIVE: To present our experience with mediastinal parathyroid cysts and summarize previously reported cases. DESIGN: We retrospectively reviewed medical records and reviewed the pertinent literature. MATERIAL AND METHODS: The clinical, operative, and pathologic findings in 7 cases of mediastinal parathyroid cysts encountered at one institution and 31 cases previously reported in the literature are described. RESULTS: Rarely, cysts may arise from an aberrant mediastinal parathyroid gland. Such cysts may manifest as a symptomatic mass, as an asymptomatic finding on roentgenography, or during the assessment of a patient with hyperparathyroidism. The diagnosis may be made by fine-needle aspiration or by excision and pathologic examination. CONCLUSION: Functioning parathyroid cysts represent degeneration of a hyperfunctioning gland, such as an adenoma, and are usually removed through a cervical approach. Nonfunctioning cysts in asymptomatic patients with normal serum calcium levels are considered indeterminate and should be managed accordingly. Excision is usually recommended.

Adult↗
PubMed1994

Evidence for a H+ nitrate symporter in Aspergillus nidulans.

Nitrate transport in Aspergillus nidulans was dependent upon a consistent proton motive force (delta p) across the cell membrane which was maintained in a range of 105 (+/- 6.7) to 131 (+/- 3.4) mV over an external pH span of 5.5 to 7.5. The membrane potential (delta psi) measured by uptake of [3H]-tetra-phenylphosphonium bromide and the transmembrane pH difference (delta pH) measured by the distribution of 3H2O and [14C]- salicylic acid were used to compute the delta p present during transport of nitrate. Energy dependent accumulation of nitrate was measured in actively assimilating and tungstate inhibited cells. A delta G for nitrate of 14 kJ mol-1 was computed from the results. Cells induced for nitrate transport maintained internal nitrate levels of 6 to 8 mM based on an internal volume of 2.6 microliters/mg dry wt as determined by a conventional dual label procedure. A fivefold higher level of cellular nitrate was observed in tungstate inhibited cells. Nitrate accumulation was dependent upon a H+ gradient which was dissipated by treatment with 2-butanol, the ionophores valinomycin and gramicidin and the proton conductors carbonyl cyanide m-chlorophenyl hydrazone and N,N'-dicyclo-hexylcarbodiimide. Significant ATP and nitrate efflux occurred in cells treated with the above agents. The results suggest that nitrate is transported by symport with H+ on a carrier which is functionally linked to a H+ ATPase pump.

Aspergillus nidulans↗