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Biomedical subjects

L R Kaiser

Publications and source records attributed to L R Kaiser.

At least 163 records · Page 9Linked to original sources
PubMed1987

Pleural mesothelioma.

Pleural mesotheliomas are uncommon tumors. Correct diagnosis of the benign variant is rarely made preoperatively, and resection is the treatment of choice and is curative. Malignant pleural mesotheliomas are locally aggressive and difficult to treat. They may be seen clinically as localized pleural tumors or as diffuse pleural disease with effusion and encasement of the lung and obliteration of the pleural space. The localized forms of malignant mesotheliomas are fibrosarcomatous. Their diagnosis and treatment do not differ from those for soft-part sarcomas seen elsewhere. Wide en-bloc excision is the treatment of choice and can be curative. The diffuse forms of malignant mesotheliomas are mainly epithelial. Treatment is generally unsatisfactory, and long-term survival is rare. Two surgical approaches are currently available: an extrapleural pneumonectomy and a pleurectomy with irradiation. The authors favor the latter approach because of its wider applicability, lower morbidity rate, and better survival advantage. Steps in selecting the best surgical mode of treatment are presented.

Adolescent↗
PubMed1987

Methods of skeletal reconstruction following resection of lung carcinoma invading the chest wall.

The 5 per cent of patients with carcinoma of the lung directly invading the chest wall present a challenge for treatment. Complete resection of all tumor, including the chest wall, should be done. Immediate reconstruction to prevent a flail chest ensures a smooth postoperative course. Excellent palliation and a 46 per cent 5-year survival rate can be achieved if there is no spread to mediastinal lymph nodes.

Fascia Lata↗
PubMed1987

Results of surgical treatment of stage III lung cancer invading the mediastinum.

From 1974 to 1984, 225 patients underwent thoracotomy at Memorial Sloan-Kettering Cancer Center for primary non-small cell lung cancer invading only the mediastinum (T3). The perioperative mortality was 2.7 per cent, and the nonfatal complication rate 13 per cent. Forty-nine patients underwent complete resection of all intrathoracic disease, with a median survival of 17 months, 3-year survival of 21 per cent, and 5-year survival of 9 per cent. Thirty-three patients underwent pulmonary resection with simultaneous iodine-125 interstitial implantation or iridium-192 delayed afterloading to areas of unresectable primary or nodal disease, with a median survival of 12 months, 3-year survival of 22 per cent, and 5-year survival of 22 per cent. One hundred and one patients underwent interstitial implantation without resection, with a median survival of 11 months, 3-year survival of 9 per cent, and no 5-year survivors. Forty-two patients had incomplete resection without intraoperative radiation therapy and fared no better than a cohort group of 44 unoperated patients with clinical evidence of mediastinal invasion--both groups had a median survival of 8 months and no 3-year survivors. An aggressive surgical approach with pulmonary resection and/or brachytherapy appears to offer some survival advantage to this group of patients. In particular, 5-year survival rates ranging from 7 to 15 per cent were observed in subsets of intraoperatively treated patients with invasion of pulmonary vein, phrenic nerve, esophagus, or pericardium and in those with clinically occult T3 disease.

Adult↗
PubMed1987

Diagnostic and therapeutic uses of pleuroscopy (thoracoscopy) in lung cancer.

Pleuroscopy (thoracoscopy) is a simple procedure to perform that has both diagnostic and therapeutic utility. With a diagnostic accuracy of 90 per cent, it should be readily performed by surgeons who treat patients with lung cancer. A well-performed pleuroscopy may spare many patients the morbidity of an unnecessary thoracotomy.

Aged↗
PubMed1987

Management of tracheobronchial lesions with the Nd-YAG laser.

Neodymium-YAG laser resection is now a well-accepted and successful treatment modality for the palliation of otherwise inoperable tumors causing symptoms of dyspnea, cough, or hemoptysis. It may provide curative therapy for benign tumors and strictures. There is a learning curve associated with the technique, but numerous "hands-on" courses are now available for acquiring the initial expertise.

Bronchial Neoplasms↗
PubMed1985

Coronary artery bypass in patients with total laryngectomy.

Patients who have undergone laryngectomy pose a challenge when they require coronary artery bypass grafting. The location of the tracheal stoma just above the jugular notch may interfere with the sternotomy, increase the risk of infection, and add some difficulty to the operative procedure. We describe the surgical technique used in 2 such patients.

Aged↗
PubMed1985

Two-dimensional echocardiography for diagnosing acute ascending aortic dissection.

The diagnosis of type A aortic dissection (involving the ascending aorta) can be made with two-dimensional echocardiography, but surgeons usually demand angiographic confirmation. Between January 1983 and February 1984, 10 patients presented at St. Michael's Hospital in Toronto with type A aortic dissection. Six patients underwent two-dimensional echocardiography early in their evaluation. A positive diagnosis was made in four, based upon visualization of an intimal flap or a false lumen. In the other two patients, the findings of an enlarged ascending aorta and pericardial effusion were suggestive but not diagnostic. Three patients survived operation and are alive and well (follow-up ranging from 3 to 5 months). One patient died while awaiting surgery, one died during aortography and one died during operation. All echocardiographic and angiographic findings were confirmed at surgery or at autopsy. It is concluded that two-dimensional echocardiography can diagnose ascending aortic dissection quickly, accurately, easily and without risk to the patient. In selected cases the presence of a false lumen or of an intimal flap makes it possible to proceed with operation without delay or the potential hazards of aortography.

Acute Disease↗
PubMed1984

Clinical thermochemotherapy. A controlled trial in advanced cancer patients.

In vitro and in vivo animal studies and some clinical trials have shown apparent benefit from thermochemotherapy; however, this treatment modality has not been adequately tested in humans. This investigation evaluated response to and toxicity of secondary thermochemotherapy, using each patient as his own control. Patients with advanced cancer who had documented disease progression while receiving chemotherapy alone were subsequently treated with the same drug, by the same dose and route, combined with localized hyperthermia. Thirty-four patients whose diseases included metastatic colon carcinoma, melanoma, sarcoma and hepatoma in viscera (29) or surface tissues (5) were treated with combination thermochemotherapy for 1 hour daily for 5 days/month. Effective heating from 41 to 45 degrees C minimum tumor temperature was possible in 17/19 (89%) tumors in which temperatures could be measured safely. The authors observed 5 (15%) tumor regressions for 1 to 5 months (median, 2 months), and 19 (56%) tumor stabilizations (growth arrest of previously progressive disease) for 1 to 9 months (median, 4 months). Subjective improvement in activity and/or pain control occurred in 6 (18%) patients and 20 (59%) had no progression of symptoms during treatment. Moreover, there was no detectable morbidity from localized hyperthermia, and no evidence of increased chemotherapy toxicity. While the mechanism(s) of response is poorly understood, the documented disease regressions and stabilizations of previously progressive disease in 24 (71%) patients during secondary combination thermochemotherapy indicates that the addition of hyperthermia may have useful anticancer activity. Expanded trials are warranted.

Adult↗
PubMed1983

Predictability of response to clinical thermochemotherapy by the clonogenic assay.

In order to assess the value of the clonogenic assay for predicting clinical response to dimethyl-triazeno-imidazole-carboxamide (DTIC) plus hyperthermia (42 degrees C), the responses of patients with measurable disease, who received combined therapy, were compared with assay results. The clonogenic assay was used independently to determine in vitro sensitivities of 53 melanomas to DTIC, with and without hyperthermia. Separate cell suspensions were incubated for 1 hour with DTIC at 37 degrees C and at 42 degrees C. In vitro sensitivity was determined by inhibition of colony formation in a double-layer agar system. Three of the 53 (6%) melanomas were sensitive to DTIC at 37 degrees C, 13 of the 53 (25%) were sensitive to 42 degrees C hyperthermia alone, and 22 of the 53 (42%) were sensitive to DTIC at 42 degrees C. Nine patients were treated with DTIC, plus hyperthermia, to the areas of their melanoma metastases (one pulmonary, four hepatic, and four subcutaneous). In five patients, the clonogenic assay results predicted positive tumor sensitivity to combined therapy, and 4 of the 5 had objective tumor regression. Tumors were resistant in vitro for four patients, and all had disease progression during treatment. Statistical analysis suggested that some responses were due to synergism of the combination of heat and drug, whereas others were due to an additive effect. The apparent direct correlation between in vitro tumor cell sensitivity to DTIC at 42 degrees C and actual clinical response to chemotherapy, plus hyperthermia, in this limited trial, has been encouraging. The clonogenic assay and in vitro evaluation of drug-heat interaction may prove helpful for selecting those patients in whom hyperthermia should be used as an adjunct to chemotherapy, and may help determine the most effective drug/heat scheduling. Further trials with other malignancies and other chemotherapeutic agents are warranted.

Cells, Cultured↗
PubMed1983

Biopsy of thoracic neoplasms for assay of chemosensitivity. New indication for thoracotomy.

Eighty-six thoracic neoplasms, both primary and metastatic, were removed at thoracotomy from 86 patients and were tested for chemosensitivity in the clonogenic assay. Substantial tumor growth was achieved in 79% (67/86). Fifty-two percent (16/31) of the primary lung tumors and 45% (15/33) of the metastatic tumors were sensitive to at least one tested drug. Clinical correlations between in vitro chemosensitivity and in vivo response were possible in 20 patients. The assay was 83% accurate for predicting in vivo sensitivity and 86% accurate for predicting in vivo resistance. The value of the assay as it pertains to lung cancer has been demonstrated. On the basis of the results, thoracotomy is indicated in selected patients as a diagnostic procedure to obtain tissue for chemosensitivity testing.

Antineoplastic Agents↗
PubMed1983

Blood flow in human tumors during hyperthermia therapy: demonstration of vasoregulation and an applicable physiological model.

A quantitative assessment of the effect of localized magnetic-loop hyperthermia on blood flow was performed in 12 human tumors using the 133Xe clearance method. Because blood flow in these tumors changed in response to needle injection, a physiologically based, one-compartment model was developed that included both a hyperemic and a steady-state component. In six tumors, changes in blood flow induced by heat were also observed. The ability of tumor vessels to respond dynamically to stress and the degree of response may be predictive of tumor heating capacity and subsequent therapeutic response.

Abdominal Neoplasms↗
PubMed1982

Thermochemotherapy for melanoma metastases in liver.

Metastatic melanoma in the liver has carried an extremely poor prognosis regardless of therapy. Because transient responses (1/6 disease regressions and 2/6 disease stabilizations for four months) in selected patients treated with intraarterial (IA) DTIC infusion were encouraging and because localized hyperthermia may be both tumoricidal and synergistic with chemotherapy, these modalities were combined for treatment of patients with advanced liver metastases. Of 10 patients treated with IA-DTIC plus heat, three (30%) had disease-regression and five (50%) had disease stabilization for 3-14 months (median 6.5 months) and survived 3.5-18 months (median 8.5 months). During treatment, 4/5 patients had pain relief and 7/10 retained or acquired normal activities. Myelosuppression was minimal and no hyperthermia toxicity occurred. A retrospective review of 10 patients with similar disease levels who were treated with conventional intravenous (IV)-DTIC indicated no responses, and no responses were seen in five patients treated with IV-DTIC plus heat. However, this latter group may have been selected patients due to the inability to place a percutaneous hepatic artery infusion catheter. This pilot study suggests that combination IA-DTIC and hyperthermia has a high response rate, is safe, and can provide quality survival for many patients.

Adult↗
PubMed1982

Clinical correlations with drug sensitivities in the clonogenic assay: a retrospective study.

We tested the ability of the in vitro clonogenic assay (CLAS) to predict clinical response for patients with solid tumors. Patients had objectively measurable disease and received at least one course of chemotherapy. The correlation between clinical responses and in vitro sensitivity was evaluated retrospectively. Tumor types included melanoma (19), sarcoma (five), hepatoma (one), and carcinoma of the stomach (two), colon (three), lung (one), and breast (one). Five patients received two separate courses of chemotherapy with different drugs or drug regimens. In nine of 11 (82%) instances, tumors were sensitive to a particular drug, and the patient had at least 50% regression of tumor following treatment with the tested drug. Two patients whose tumors were sensitive in vitro had no evidence of clinical response. In 25 of 26 assays, the CLAS accurately predicted tumor resistance, and only one patient had evidence of clinical response (96%). Associations of in vitro results with clinical responses were highly significant. The CLAS can accurately predict the chemosensitivity of a variety of solid tumors.

Antineoplastic Agents↗
PubMed1982

Radiographic features of osseous metastases of soft-tissue sarcomas.

In contrast to most other neoplastic processes of bone, in our study osseous metastases from soft-tissue sarcomas (STS) were more reliably detected by radiography than by scintigraphy. The radiographic manifestations of 65 skeletal metastases in 23 patients with STS were reviewed. Although most metastases (88%) were osteolytic, eight (12%) lesions were osteoblastic. The destructive patterns were geographic in 29%, moth-eaten in 55%, and permeative in 12% of the lesions. The axial skeleton was most commonly involved. In the long bones the diaphyses were the predominant sites of involvement. The bony cortex was frequently breached, with resultant soft-tissue swelling and pathologic fractures. Noteworthy features included subarticular location, involvement of the sacroiliac joint, and an expansile appearance.

Adolescent↗
PubMed1982

Clinical radiofrequency hyperthermia: a review.

Localized radiofrequency (RF) hyperthermia is being investigated for potential use in cancer therapy, both as a single agent and in combination with radiation therapy and chemotherapy. Standard capacitive and inductive heating techniques and new technology, including magnetrode magnetic-loop induction, are being compared for safety and efficacy. Clinical trials suggest that effective localized RF hyperthermia may be administered safely to both superficial and deep visceral tumors with proper equipment. Temperatures of 42 degrees C or greater appear to be tumoricidal, though higher temperatures and longer and multiple treatments seem most beneficial. Effective heating of tumors has been independent of histology but could be related to size and blood flow. Combined with radiation therapy and chemotherapy, hyperthermia appears to have a synergistic or additive effect. These trials indicate that localized RF hyperthermia may soon provide a significant contribution to our armamentarium against cancer.

Adenocarcinoma↗