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T W Shields

Publications and source records attributed to T W Shields.

At least 19 recordsLinked to original sources
PubMed1992

Screening, diagnosis, and staging of non-small cell lung cancer and consideration of unusual primary tumors of the lungs.

Refinements of computed tomographic (CT) scanning techniques, such as high-resolution CT, CT densitometry, and contrast enhancement CT, have been shown to improve diagnostic accuracy in differentiating between benign and malignant lung nodules. Unfortunately, none of these techniques is fail proof, and, even when a lesion is considered to be benign, periodic observation is mandatory. In staging the locoregional extent of lung cancer, magnetic resonance imaging has not been shown to be superior to CT scanning and should not be substituted for or used in addition to CT except in special situations. Transesophageal ultrasonography, which identifies additional mediastinal lymph nodes that are not visualized by CT scanning, may become an important adjunct in the clinical staging of the regional extent of the disease. Study findings have supported the value of pleural lavage cytology at thoracotomy. Additional studies of the technique as a prognostic factor should be conducted in patients with resected early-stage disease. The high incidence of cerebral metastasis in patients with adenocarcinoma and stage III disease suggests the possible value of routine use of CT scans in this subset of patients who, otherwise, have potentially resectable lung tumors. However, no evidence supports routine scanning in patients with stage I or II disease. The low sensitivity of abdominal CT scans in identifying adrenal metastatic involvement further decreases the value of using this examination routinely to identify occult adrenal metastatic disease.

Carcinoma, Non-Small-Cell Lung↗
PubMed1991

Screening, staging, and diagnostic investigation of non-small cell lung cancer patients.

Despite its appeal, lung cancer screening has been found to be of little value at this time. However, use of monoclonal antibodies to detect cancer cells in the sputum may prove to be of value in high-risk subjects. Once a cancer is diagnosed, anatomic staging by the International TNM Staging System has shown its effectiveness in directing the appropriate therapeutic interventions and predicting prognosis. Anatomic staging cannot be completely accomplished by computed tomography scans or magnetic resonance imaging of the chest, particularly relative to mediastinal lymph node involvement or to direct mediastinal extension of the tumor. To determine lymph node involvement, preoperative mediastinal exploration is indicated for all potentially operable patients in whom the lymph nodes are 1 cm or greater. Although a small percentage of normal-sized lymph nodes will contain tumor, routine investigation is not believed necessary. Direct mediastinal invasion as suggested by the computed tomography scan is most often indeterminate and thoracotomy is necessary in most instances to determine the resectability of the tumor. Data continue to accumulate showing that routine scanning of asymptomatic patients for the presence of metastatic disease to the brain or skeletal system is not effective.

Carcinoma, Non-Small-Cell Lung↗
PubMed1990

The significance of ipsilateral mediastinal lymph node metastasis (N2 disease) in non-small cell carcinoma of the lung. A commentary.

The significance of the presence of N2 disease in patients with non-small cell cancer of the lung is widely misunderstood. Long-term survival rates from 15% to more than 30% after surgical resection are frequently reported in the literature. However, these percentages represent only the surgical results in a highly selected and unfortunately small proportion of the entire number of patients with N2 disease. In those patients in whom N2 disease is readily clinically recognizable or is identified by standard roentgenographic or bronchoscopic study and proved by biopsy or is discovered by prethoracotomy mediastinal exploration, a 5-year survival rate of only approximately 2% for the entire group can be expected, even when aggressive surgical resection is performed when appropriate. In those patients in whom the N2 disease is only initially recognized at thoracotomy, the resectability rate is higher and 5-year survival rates as noted are in the range of 15% to 30%. Although surgical resection continues to be the primary choice of therapy in this small group (less than 20% of patients with N2 disease), surgical resection can be expected to salvage only 3% to 6% of all patients with N2 disease. Thus, with presently available therapy, the vast majority of patients proved to have N2 disease will die of their lung cancer. It must be concluded that N2 disease is a significant poor prognostic factor in patients with lung cancer.

Carcinoma, Non-Small-Cell Lung↗
PubMed1989

The importance of surgical and multimodality treatment for small cell bronchial carcinoma.

In a cooperative international lung cancer multimodality treatment trial, 112 patients with small cell lung cancer underwent initial surgical resection and were then randomized to receive one of two intensive postoperative chemotherapeutic regimens, followed by prophylactic cranial irradiation in the disease-free patients. Regimen A consisted of eight courses of cyclophosphamide, doxorubicin, and vincristine and regimen B of two courses of three sequential drug combinations: (1) cyclophosphamide, lomustine, and methotrexate; (2) cyclophosphamide, doxorubicin, and vincristine; and (3) ifosfamid and etoposide. In 47 patients the diagnosis was known preoperatively and in 65 it was not confirmed until the resected specimen was examined (all diagnoses were reviewed by a referee pathologist). Each patient was classified by the pathologic TNM characteristics. There were 38 patients with stage I disease, 39 patients with stage II, and 35 patients with stage IIIa disease. In stage IIIa there were nine patients with T3 N0-1 disease and 26 with T1-3 N2 disease (most N2 disease was clinically undetected until thoracotomy or was discovered only by routine histologic examination of the resected mediastinal nodes). Early survival rates at 24 months calculated by the life table method are as follows: stage I, 76%; stage II, 56%; and stage IIIa, 49% (T3 N0-1, 89%; T1-3 N2, 35%). Survival rates at 36 months are 62%, 50%, and 41% (74% and 29%), respectively. The projected 36-month survival rate for 43 patients with N0 disease is 65%; for 43 with N1 disease, 52%; and for 26 with N2 disease, 29%. No difference in survival has been noted in either chemotherapy treatment group. It is concluded that initial surgical resection for limited small cell cancer (stage I, II, and T3 N0-1) followed by intensive chemotherapy is an appropriate therapeutic approach. For T1-3 N2 disease the results are inconclusive.

Actuarial Analysis↗
PubMed1989

New approach to defibrillator insertion.

The automatic implantable cardioverter/defibrillator has become an integral part of the management of patients with life-threatening ventricular rhythm disturbances. The considerable size of the device (250 gm, 10.8 by 7.6 cm) results in protrusion from the abdominal wall, with an associated alteration in self-image in all patients. In thin patients, erosion through the skin can occur. We have devised an operation in which the generator is implanted in, and becomes part of, the chest wall. The two patients in whom this approach has been used are virtually unaware of the presence of the device. We propose this operation as an alternative to abdominal wall insertion when the latter is unsuitable for technical reasons.

Aged↗
PubMed1988

Neurogenic tumors of the thorax.

Neurogenic tumors of the thorax are observed in all age groups, although they are rare in the elderly. They are more likely to be malignant in the child than in the adult. Tumors of the autonomic system are common in children, whereas the nerve sheath tumors are more likely to be found in adults. The malignant lesions are almost always symptomatic and the benign lesions asymptomatic, except in the child, in whom a benign lesion may result in symptoms because of its size relative to the volume of the child's thorax. Intraspinal canal extension, although relatively infrequent, should be sought for in all paravertebral tumors, for a significant percentage of these may be initially asymptomatic. Excision of such an hourglass tumor without foreknowledge of such extension may lead to serious spinal cord complications. Surgical excision of most of these tumors is sufficient except for the malignant lesions, especially in infancy and childhood, for which the addition of postoperative irradiation and chemotherapy may be beneficial. The prognosis after the removal of benign neurogenic tumors of the thorax is excellent. In the infant or child with Stage III or IV neuroblastoma, ganglioneuroblastoma, or an Askin tumor, the prognosis is poor. In the adult with a malignant neurogenic sarcoma or a malignant paraganglioma, the prognosis likewise is grave.

Autonomic Nervous System Diseases↗
PubMed1987

Cisplatin and 5-fluorouracil in the primary management of squamous esophageal cancer.

A combined treatment program consisting of chemotherapy with cisplatin and infusion 5-fluorouracil (5-FU) for three cycles followed by esophagectomy or radiation, or both, has been conducted in 26 patients with squamous cancer of the esophagus localized to the primary site. Eleven patients had objective evidence of partial or complete response to the chemotherapy. Fourteen patients were operated on and ten underwent total esophagectomy. Drug toxicity was considerable with severe mucositis and myelosuppression occurring in 11 and seven patients, respectively. There were no drug-related deaths. Median survival is 17.8 months. Ten patients have lived more than 2 years. Six of these patients have undergone total thoracic esophagectomy after the induction chemotherapy. Determination of the ultimate benefits of combined modality therapy may require prospective randomized trials isolating the major treatment components but our data suggest that chemotherapy contributes to improved results in this disease and that drug therapy is emerging as an integral component of combined therapy.

Aged↗
PubMed1987

Mortality and morbidity of gastric 'pull-up' for replacement of the pharyngoesophagus.

Forty-two patients have undergone gastric interposition to replace the pharyngoesophagus; 39 patients had primary or recurrent malignant tumors of the hypopharynx, cervical esophagus, postcrioid area, or tracheal stoma, while three patients had benign disease. The operation consisted of resection of the local neck disease, along with a transhiatal esophagectomy and gastric "pull-up" for restoration of gastrointestinal tract continuity. Eight hospitalized patients died, for a mortality rate of 19%, of which six patients died of complications from local sepsis. The more common nonfatal complications were related to the neck wound, the anastomosis, and the stomach. The complication rate per patient, excluding postoperative deaths, was 40%. The average length of stay was 44 days for the patients with nonfatal complications and 23 days for those without complications. The success rate of the operation with relief of the patients' presenting symptoms was 81%.

Adult↗
PubMed1987

Effects of exercise and food restriction on body composition and metabolic rate in obese women.

Obese women (140-180% of ideal body weight) were studied on a metabolic ward during 1 wk of maintenance feeding, followed by 5 wk of 800 kcal/d (liquid formula diet). Five subjects participated in a supervised program of daily aerobic exercise and three subjects remained sedentary. Total weight loss was not different between exercising and nonexercising subjects but significantly more of the weight loss came from fat and less from fat-free mass in the exercising subjects. Resting metabolic rate (RMR) declined similarly in both groups (approximately 20%), even though exercising subjects were in greater negative energy balance due to the added energy cost of exercise. In summary, results from this controlled inpatient study indicate that exercise is beneficial when coupled with food restriction because it favors loss of body fat and preserves fat-free mass.

Adult↗
PubMed1987

Selective preoperative evaluation for possible N2 disease in carcinoma of the lung.

The efficacy of computed tomography and surgical mediastinal exploration in determining tumor resectability were retrospectively evaluated in 92 consecutive patients with non-small cell lung carcinoma. Status of mediastinal nodes was ultimately determined by surgical mediastinal exploration or thoracotomy. Patients were divided into three groups on the basis of chest roentgenography: Group I comprised 30 patients with peripheral T1 or T2 lesions with normal hilar and mediastinal shadows. Only one patient was found to have an involved node. Chest roentgenography had an accuracy rate of 96% and computed tomography, 93%. Thoracotomy is recommended without either computed tomography or surgical mediastinal exploration in this group. Group II comprised 47 patients with T1 or T2 lesions with an abnormal hilus, an abnormal mediastinal shadow, or either the hilus or mediastinum obscured by overlying parenchymal disease. Computed tomography revealed mediastinal nodes 1 cm or greater in size (abnormal node group) in 21 patients (45%) and smaller than 1 cm (normal node group) in 26 patients (55%). Surgical mediastinal exploration was performed in the abnormal node group and involved nodes were found in 17 of 21 patients (81%). In the normal node group, thoracotomy only was performed and no involved nodes were found. Computed tomography is recommended in all patients in Group II. Patients in the normal node group may be subjected to thoracotomy only and those in the abnormal node group should undergo surgical mediastinal exploration as the next diagnostic step before thoracotomy. Group III comprised 15 patients with grossly abnormal mediastinal shadows. Findings from computed tomography were abnormal in all 10 patients in whom it was done. Surgical mediastinal exploration was done in all 15 and yielded abnormal results in 14. It is recommended in this group that computed tomography is unnecessary and surgical mediastinal exploration should be the only diagnostic procedure. Thus, in potentially resectable non-small cell lung carcinoma, the use of computed tomography and surgical mediastinal exploration should be selective and should be determined by appropriate initial interpretation of the chest roentgenogram.

Carcinoma, Non-Small-Cell Lung↗
PubMed1986

Surgery of small cell lung cancer.

The role of surgical resection in the management of patients with small cell lung cancer remains to be defined. Some data suggest the potential benefit of resection in the few patients with very limited disease (peripheral T1N0 and T2N0 lesions), and there are chemotherapy regimens with 80-85% response rates in patients with more extensive but still localized disease. Interest has been reawakened in the role of adjuvant surgical resection in selected patients by 2 approaches: in patients with peripheral T1 or T2 lesions with negative mediastinal exploration, initial surgical resection followed by an adequate chemotherapeutic regimen and prophylactic cranial irradiation has resulted in an 80% disease-free survival at 30 months; initial chemotherapy in patients with only localized disease is followed by resection in the responders. Approximately 30% of the responders have undergone exploratory thoracotomy after completion of the chemotherapy. Local irradiation, as well as prophylactic cranial irradiation, generally has been used postoperatively. Early pilot studies suggest benefit of this approach in patients found to have T1-3 N0-1 disease but not in those with N2 disease. Prospective, randomized, clinical trials by the Lung Cancer Study Group in North America and its counterparts in Europe are now being carried out in hopes of supplying definitive data relative to this multi-modality therapy in small cell lung cancer. Unfortunately, no data are available to date.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1979

Pseudosarcoma of the esophagus. Three new cases and review of the literature.

Three newly found patients with an esophageal pseudosarcoma are described. The features of this unusual polypoid tumor are reviewed based on these three patients and 21 additional reported patients. The origin of the sarcomatous element as a metaplastic reaction to the underlying carcinoma is discussed. The exuberant growth may present with obstructive symptoms earlier than the usual carcinoma of the esophagus, permitting curative surgical resection in some patients.

Aged↗