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T W Shields

Publications and source records attributed to T W Shields.

At least 19 recordsLinked to original sources
PubMed1999

Mediastinal parathyroid cysts revisited.

BACKGROUND: A case of a functioning mediastinal cyst is presented. METHODS: A comprehensive review of the literature found 93 patients in whom a parathyroid cyst or cysts extended into, or was completely contained within, the mediastinum. Including our patient, there were 46 men and 45 women, and the gender was not recorded in three. RESULTS: The cysts were located in the anterosuperior region in 56 patients, in the middle region of the mediastinum in 26, and in the anterior, prevascular region in 12. Thirty-nine patients had functioning cysts associated with hyperparathyroidism of varying severity; seven patients presented with a hypercalcemic crisis. Local symptomatology consisted of a neck mass, respiratory distress, and occasional dysphagia or chest pain. Recurrent laryngeal nerve paresis was present in nine patients, and innominate vein compression or thrombosis was present in two. The cysts in all but four patients were treated by open surgical excision; two were treated by thoracoscopy, and two patients only had fine-needle aspiration of the cyst. The cyst was excised via a cervical approach in 67 patients and by a thoracotomy or median sternotomy or a variation thereof in 23. There was no operative mortality and morbidity was minimal. CONCLUSION: Surgical resection was successful in all and remains the treatment of choice for mediastinal parathyroid cysts.

Female↗
PubMed1997

Lymphoepithelioma-like carcinoma of the lung.

Primary lymphoepithelioma-like carcinoma of the lung is rare; only 26 case reports have been identified in the literature. The present report presents a case of a 67-year-old white man with a T1 N1 M0 lymphoepithelioma-like carcinoma of the lung. He presented with severe arthritic complaints that resolved after resection of the tumor. The majority of these tumors have occurred in Asian patients who have shown evidence of previous exposure to the Epstein-Barr virus.

Aged↗
PubMed1995

Primary malignant melanoma of the esophagus.

Primary malignant melanoma of the esophagus is a rare disease. A case is reported and the newer diagnostic techniques of immunohistologic identification of the tumor by positive reaction to the HMB-45 antigen, as well as immunoscintigraphy with Technetium-99m-labeled melanoma monoclonal antigen for the demonstration of distant metastasis, is presented. A current review of the literature on this uncommon tumor is presented, and treatment options are discussed. A total esophagectomy remains the treatment of choice. Four long-term (> 5 years) survivors after adequate surgical removal have been recorded in the literature.

Antibodies, Monoclonal↗
PubMed1993

Surgical therapy for carcinoma of the lung.

Surgical excision of lung cancer remains the treatment of choice for those patients with non-small-cell lung cancer who are determined to have stage I or stage II disease and who have the physiologic capacity to tolerate the planned resection. With proper selection, a number of patients with stage IIIa disease, including a small percentage of those with N2 disease, and a very small highly selected group of patients with stage IIIb (tracheal or carinal involvement) or even stage IV disease (solitary brain metastasis), may be surgical candidates. The resection must be complete to be successful, but also should be as conservative of normal lung tissue as is consonant with this goal. Immediate postsurgical mortality should be no greater than 3% to 6% for the majority of procedures except those associated with some extended resections. Five-year survival rates of 35% to 40% in all resected patients to as high as 80% for those patients with very limited (T1, N0, M0) disease can be anticipated. The use of adjuvant therapy has been disappointing for any significant prolongation of survival. Neoadjuvant therapy has yet to be appropriately evaluated. Surgical resection in the multimodality approach to the treatment of small-cell lung cancer continues under investigation but appears to play a minimal role except in those patients with very early limited disease (stage I and an occasional patient with limited T3, N0 disease). Lymph node involvement appears to preclude beneficial resection except under special circumstances. Currently all resected small-cell lung cancer patients are believed to be most appropriately managed with the addition of standard chemotherapy. The role of irradiation, either local or cranial, in the resected small-cell lung cancer patient is unsettled.

Carcinoma, Non-Small-Cell Lung↗
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↗