Clinical utility of PET-FDG imaging in differentiation of benign from malignant adrenal masses in lung cancer.

This study was designed to evaluate the sensitivity, specificity, and predictive accuracy of PET-FDG imaging in detecting metastatic disease involvement of adrenal glands in patients with lung cancer. We wanted to compare efficacy of positron emission tomography (PET)-fluorodeoxyglucose (FDG) imaging to computed tomography (CT) scanning in differentiating benign from malignant involvement of adrenal glands in patients with lung cancer. Thirty patients with biopsy-proven lung cancer and abnormal findings on PET and/or CT scanning were studied for presence of adrenal abnormality suggestive of metastatic disease involvement (n = 26) or benign adrenal enlargement (n = 4). The results of PET and CT scanning were compared to histological findings and/or clinical follow-up for at least 1 year for presence or absence of adrenal metastases. PET-FDG imaging correctly detected the presence of metastatic involvement in 17 of 18 patients and excluded metastatic involvement in 11 of 12 patients for sensitivity, specificity, and accuracy of 94.4%, 91.6%, and 93.3%, respectively. CT scanning showed enlarged adrenals without metastases in 8 of 30 patients and normal-sized adrenals in the presence of metastases in 5 of 30 patients. There was a false-positive PET finding in 1 patient and a false-negative PET finding in another patient. PET-FDG imaging is a highly sensitive, specific, and accurate test to differentiate benign from malignant involvement of adrenal glands in patients with lung cancer and often ambiguous findings on CT scanning.

Comparative efficacy of positron emission tomography with fluorodeoxyglucose in evaluation of small (<1 cm), intermediate (1 to 3 cm), and large (>3 cm) lymph node lesions.

PURPOSE: Our objective was to determine if positron emission tomography (PET) with fluorodeoxyglucose (FDG; PET-FDG) imaging is equally efficacious in detection of metastases in small and large mediastinal lymph nodes as compared to CT scanning. MATERIALS AND METHODS: PET-FDG imaging, CT scanning, and histology results of sampled mediastinal lymph nodes were compared in 54 patients of total 118 patients studied. Efficacy of PET and CT was determined and compared in small (< 1 cm), intermediate (1 to 3 cm), and large (> 3 cm) mediastinal lesions. RESULTS: PET was accurate in 94% of patients in characterizing "N" disease as compared to 61% with CT. Overall, sensitivity, specificity, and accuracy of PET for staging mediastinal lymph nodes (n = 168 in 54 patients) was 96, 93, and 94%, as compared to 68, 65, and 66% with CT. Positive and negative predictive value of PET in detecting mediastinal adenopathy was 86% and 98%, as compared to 47% and 82% with CT, respectively. PET was also highly reliable and accurate for detecting lymph nodes < 1 cm, 1 to 3 cm, and > 3 cm in size with superior efficacy than CT. Sensitivity, specificity, and accuracy of PET for detecting malignancy in lymph node lesions < 1 cm in size was 97, 82, and 95%, respectively. CONCLUSION: PET-FDG imaging is equally reliable and accurate for detecting disease in small and large lymph node lesions in patients with suspected or proven lung cancer with better efficacy than CT.

Current status of the diagnosis and treatment of thymoma.

Although thymomas are rare neoplasms, they are the most common tumor of the anterior mediastinum in adults. Preferred therapy for these neoplasms is complete surgical resection. If a thymoma cannot be completely resected, postoperative radiotherapy may produce satisfactory results in controlling the tumor. Significant 5- and 10-year survival rates have been recorded for patients with advanced thymomas who have been treated by radiation therapy alone. Chemotherapy may be used in patients with unresectable thymomas as well, but the results are less promising than with radiotherapy. Combinations of radiotherapy and chemotherapy used on patients with unresectable thymomas have produced encouraging results. Surveillance of patients with thymoma should be prolonged because late recurrence (more than 5 years after initial therapy) can be expected in a significant minority of patients. Aggressive therapy of late recurrence, including resection of new tumor masses and pleural metastases, has yielded successive disease-free intervals that validate persistent treatment.

Utilization of muscle flaps in the treatment of bronchopleural fistulas.

This paper reports the results of a series of 5 patients who underwent closure of persistent bronchopleural fistula using extrathoracic muscle flaps over a 6-year period. All patients had failed more conservative treatment. The surgeries were one- or two-stage procedures performed with the collaboration of cardiovascular and reconstructive surgical staffs. There were no associated mortalities. The muscle flaps utilized were the latissimus dorsi, serratus anterior, pectoralis major, pectoralis minor, and trapezius. The results have been encouraging and allowed the complete closure of the bronchopleural fistula in the majority of patients. The authors present the best management of this serious disease, as well as its pathophysiology and clinical aspects.

Chest wall resection and reconstruction.

Chest wall reconstruction has been refined and expanded in recent years so that almost any defect may be repaired with an excellent cosmetic and physiological result. The first step in a good reconstruction is an appropriate and thorough resection that leaves healthy, viable margins to which the materials and tissues used in a reconstruction may be anchored securely. In most instances, chest wall stabilization will not be necessary. In some cases in which large areas of chest wall will be removed or a lateral aspect of a chest wall needs to be resected, stabilization may be necessary. Stabilization may also be required in patients who suffer from debilitating lung disease and need a chest wall resection and reconstruction. Soft tissue coverage completes the reconstruction by moving healthy, viable tissue to fill the defect. In most instances, pedicled muscular, musculocutaneous, and omental flaps will provide adequate soft tissue coverage. Very infrequently, a free flap will be necessary to achieve total closure of a chest wall defect. The soft tissue coverage is completed by using meshed, split thickness skin grafts to provide epithelialization of any exposed muscle or omentum.

Current management of thymoma.

Patients with thymoma present rarely even on active thoracic surgery services. These patients may suffer from many associated conditions but the most common is myasthenia gravis. Aggressive surgical resection is the mainstay of initial therapy. Radiation therapy has a role in patients who are left with retained neoplasm after surgical resection. Recurrence may occur at prolonged intervals but should be treated aggressively.

Positron emission tomographic imaging with fluorodeoxyglucose isefficacious in evaluating malignant pulmonary disease.

OBJECTIVE: Positron emission tomography (PET), when used with the intravenously administered radiopharmaceutical F-18 fluorodeoxyglucose (FDG), has the potential to help in the evaluation of patients with lung cancer because the radiopharmaceutical is concentrated by metabolically active cells. We conducted a retrospective study of PET-FDG in 96 patients evaluated at our institution over the past 2 years for suspected primary pulmonary neoplasms. PET-FDG results were compared with the findings of computed tomographic scans on the same patients. All patients underwent surgical exploration with or without resection of the malignant tumors. Sites of potential malignancy were subjected to biopsy and/or excision, with subsequent pathologic evaluation. RESULTS: A total of 96 patients with suspected or proven primary pulmonary malignant disease were evaluated. Sixty-six patients had histologically confirmed malignant tumors, and 30 had benign masses histologically. PET-FDG had an accuracy of detecting malignancy in pulmonary lesions of 92% (sensitivity 97%; specificity 89%). A total of 111 surgically sampled sites were from lymph nodes. PET-FDG was accurate in predicting the malignancy of nodes in 91% of instances, whereas computed tomography was correct in 64%. The sensitivity, specificity, and predictive accuracy of PET in detecting metastatic lymphadenopathy in mediastinal lymph nodes were 98%, 94%, and 95%, respectively. PET-FDG also changed the M stage in 8 (12%) patients (6 with and 2 without metastases). The 6 malignant (positive) lesions were correctly identified by PET-FDG, and the 2 without tumor were accurately predicted as benign (negative). CONCLUSION: These initial results suggest that PET-FDG is highly accurate in identifying and staging lung cancer. PET-FDG also appears to be more accurate in detecting metastatic mediastinal lymphadenopathy than computed tomographic scan.

Comparative efficacy of positron emission tomography with FDG and computed tomographic scanning in preoperative staging of non-small cell lung cancer.

OBJECTIVE: To determine the sensitivity, specificity, and accuracy of positron emission tomography with 2-fluorine-18-fluorodeoxyglucose (PET-FDG) in the preoperative staging (N and M staging) of patients with lung cancer. The authors wanted to compare the efficacy of PET scanning with currently used computed tomography (CT) scanning. MATERIALS AND METHODS: Results of whole-body PET-FDG imaging and CT scans were compared with histologic findings for the presence or absence of lymph node disease or metastatic sites. Sampling of mediastinal lymph nodes was performed using mediastinoscopy or thoracotomy. RESULTS: PET-FDG imaging was significantly more sensitive, specific, and accurate for detecting N disease than CT. PET changed N staging in 35% and M staging in 11% of patients. CT scans helped in accurate anatomic localization of 6/57 PET lymph node abnormalities. CONCLUSION: PET-FDG is a reliable method for preoperative staging of patients with lung cancer and would help to optimize management of these patients. Accurate lymph node staging of lung cancer may be ideally performed by simultaneous review of PET and CT scans.

Arachidonic acid metabolism by adult human osteoblast-like cells exhibits sexually dimorphic characteristics.

The eicosanoids, including prostaglandin E2 (PGE2) and other bioactive arachidonic acid metabolites, are important local mediators of bone remodeling. Presumably, the limited or excessive synthesis of the eicosanoids could compromise bone homeostasis. We have noted that the stimulated release of arachidonic acid by adult male donor derived human osteoblast-like (hOB) cells exceeded the stimulated release measured for female-derived hOB cells by 1.5-fold. Assays of PGE2 biosynthesis by cytokine-stimulated hOB cells also demonstrated a sex-linked difference, such that male hOB cell PGE2 production exceeded female cell production by 1.6-2.2-fold. The calcium-dependent cytoplasmic phospholipase A2 activity in subcellular fractions prepared from hOB cell homogenates was higher in both the cytosolic (1.6-fold) and particulate (1.5-fold) fractions from the male cells than in those prepared from female hOB cells, suggesting a molecular basis for the observed sexually dimorphic characteristics related to arachidonic acid metabolism by hOB cells. The relatively limited capacity of the female cells may limit needed intracellular and intercellular signaling during bone remodeling, thereby contributing to the development of bone pathology.

Right atrial metastatic melanoma in a patient with transient ischemic attacks.

A 65-year-old-man was admitted for evaluation of a transient ischemic attack. A 4.5 x 5.3-cm right atrial mass and a patent foramen ovale were identified by echocardiography. A 0.5-cm lesion was identified in the left temporal lobe of the brain by magnetic resonance imaging. Positron emission tomography was used to differentiate a tumor from an infarct in the brain. The cardiac and the brain lesions were successfully resected. Histopathologic study of the atrial and cerebral tissue demonstrated that these were metastases from a previously excised scalp desmoplastic malignant melanoma. The patient remains well at 14 months' follow-up.