Richard B. McElvein

Hyperthermia with implanted electrodes: In vitro and in vivo correlations

Hyperthermia as a treatment for cancer has elicited much recent interest. However, major difficulties persist both in the technology for heating deep-seated tumors, and in thermal dosimetry. We have investigated a heating technique for deep-seated neoplasms that employs an internal implanted electrode and an external electrode to apply radiofrequency current to a tumor mass. The internal electrode consists of an array of stainless steel needles or wires which define a Faraday cage within the tumor, while the external electrode consists of a variety of electrical conductors at the skin surface. Phantom measurements have closely reproduced calculated temperature distributions. The temperature profiles within the volume enclosed by the internal electrode show relatively homogenous heating. Temperature measurements in a rat tumor model have demonstrated that significant heating within such an internal electrode array is easily obtained. The heating may extend some centimeters outside the electrode. Using a dog model we have shown that with such a treatment technique the temperature profiles obtained are reproducible both spatially and temporally. A case report of a clinical application is presented. A 5 cm bronchogenic carcinoma was easily heated without significant heating of the surrounding normal lung, and without apparent toxicity. Such a technique may be applicable to a variety of operable but unresectable neoplasms. The reproducibility and relative homogeneity of heating suggest possible usefulness in combined modality trials.

Transthoracic Exposure for Anterior Spinal Surgery

The anterior approach to the vertebral column is used to treat fractures, spinal deformities, and destructive lesions secondary to tumor or infection. The thoracic surgeon, working with orthopedic surgeons and neurosurgeons, is uniquely qualified to provide surgical exposure expediently and assist in postoperative care. Forty-five patients with spinal deformities secondary to trauma (18 patients), congenital anomalies (16 patients), neoplastic disease (7 patients), and inflammation (4 patients) were treated by a transthoracic (37 patients) or thoracoabdominal (10 patients) anterior approach to the vertebral column. Two patients had subsequent operations. Free and vascularized rib grafts were used for stabilization and fusion with good results and few complications (8 patients). These results indicate that interspecialty cooperation results in expedient surgical exposure and good postoperative care.

Indications, results, and complications of bronchoscopic carbon dioxide laser therapy.

A carbon dioxide laser coupled with a rigid ventilating bronchoscope has been used to treat 94 patients with symptomatic obstructing lesions of the trachea and main stem bronchi. Fifty-nine patients had malignant disease and 35 had benign disease. The results in the 35 patients with benign disease have been good except for patients with airway deformity who required subsequent reconstruction. The results in the 59 patients with malignant disease have been satisfactory. Six patients died in the immediate postoperative period, five died within 30 days of treatment, and of the remaining, 24 are alive with an average life span of 14.3 months.

Early Thoracotomy for Pyogenic Empyema

horacic empyema, although currently not common, persists despite the introduction and widespread use of antibiotics for pulT monary inflammatory disease. Historically many different microorganisms have been responsible, but in recent years coagulase positive Staphylococcus aureus and the hemolytic streptococcis have been the more common infecting agents. When treatment of pulmonary infections is delayed or inadequate, empyema may occur. A small number of patients develop empyema despite prompt and adequate therapy.

CT manifestation of non-Hodgkin's lymphoma as a solitary pulmonary nodule in a patient with acquired immunodeficiency syndrome

We present a case of acquired immunodeficiency syndrome with primary pulmonary non-Hodgkins lymphoma that manifested as a solitary pleura-based mass lesion. Its differentiation from an infectious process imposed a diagnostic dilemma. The importance of awareness of such an entity for earlier diagnosis is stressed.

A Method of Early Irrigation of the Contaminated Postpneumonectomy Space

A modified balanced drainage system was used with other measures in a patient with an obstructing pulmonary carcinoma, infection, and necrosis. Management included right pneumonectomy, perioperative systemic antibiotics, protection of the remaining lung, and a modified balanced drainage system that allowed early irrigation of the postpneumonectomy space. On the tenth postoperative day, irrigations were discontinued, the right chest was filled with an antibiotic solution, and the thoracostomy tubes were removed. The mediastinum remained in a satisfactory position, and the patient recovered without evidence of empyema. He died of a cerebral metastasis five and a half months postoperatively. This method combines principles that have been used for many years. A balanced drainage-irrigation system permits early irrigation of the contaminated postpneumonectomy space while the mediastinum is still mobile. Prolonged hospitalization and formal closure of the thoracostomy sites can be avoided.

Solitary neurofibroma of the vagus nerve in the aortopulmonary window masquerading as a developmental cyst.

A rare case of solitary neurofibroma of the vagus nerve in the aortopulmonary window masquerading as a developmental cyst is reported. Its computed tomographic characteristics and magnetic resonance imaging are described and correlated with pathologic findings. Although the features of such imaging modalities are quite characteristic for a neurofibroma, its differentiation from atypical developmental cysts may be difficult.

Enzymatic Disaggregation of Human Bronchogenic Carcinomas followed by Velocity Sedimentation of Cells

Publisher Summary This chapter discusses the enzymatic disaggregation of human bronchogenic carcinomas followed by velocity sedimentation of cells. Tumors are heterogeneous populations of neoplastic cells, blood cells, and stromal cells including lymphocytes, macrophages, and plasma cells. The biological and chemical characterization of tumors would be facilitated if solid tumors could be quantitatively disaggregated into suspensions of viable cells. The malignant cells in human lung carcinomas often comprise 50% or less of the total cells in the tumor. Thus, the biochemical changes that accompany malignant transformation will be more apparent when purified malignant cells are compared with purified normal epithelial cells. In a study described in the chapter, patients with widely disseminated lung carcinoma had elevated levels of urinary hexosaminidase compared to a healthy control population, and most patients who responded to therapy showed decreasing levels of urinary hexosaminidase. The theory and applications of cell separation by velocity sedimentation in isokinetic gradients have been used. Gradients of Ficoll were constructed with a two-chambered gradient generator. The isokinetic gradient is most useful for separating cells with different diameters, but the densities of cells also contribute to the sedimentation patterns. Gradients were centrifuged. Velocity sedimentation in isokinetic gradients of Ficoll in JTCM resulted in enriched preparations of both stromal cells and malignant cells from the same lung tumors.

Computed tomography evaluation of pathologic processes in the potential spaces of the mediastinum

The potential spaces of the mediastinum can be involved in a variety of disease processes and become evident by computed tomography study. The potential spaces may be distended with air, blood, inflammatory exudate, excessive fat, or tumor which separates and displaces the normal mediastinal structures. Seven cases with various pathologic processes are selected to demonstrate the computed tomography characteristics of such lesions. We emphasize the importance of computed tomography in evaluating and understanding various disease processes involving the potential spaces in an often widened mediastinum.