PubMed HealthSearch

Biomedical subjects

R Kröger

Publications and source records attributed to R Kröger.

10 recordsLinked to original sources

Early diagnosis and treatment of spinal epidural metastasis in breast cancer: a prospective study.

This prospective study evaluated the usefulness of myelography in breast cancer patients who present with radiculopathy or myelopathy. A total of 124 consecutive myelograms were performed in 100 patients. Epidural metastasis (EM) was diagnosed in 67 myelograms (54%). Multiple epidural metastases were diagnosed in 15 (22%) of those, resulting in a total of 87 epidural lesions. A complete block was found in 13 EM (15%) and an incomplete block in 14 EM (16%). Clinical data could not predict the site of EM in 29 cases (33%). Fifteen asymptomatic EM were detected in myelograms with multiple EM. Plain radiographs were of no value in determining the site of EM in 29 cases (33%), including 13 cases (15%) without vertebral metastasis at the site of EM. Treatment consisted of radiotherapy (RT) with or without systemic treatment in 52 cases (80%), systemic treatment alone in 11 cases (17%) and surgery in two patients (3%). Clinical improvement was noticed in 72%, no change in 13%, and deterioration in 15%. No difference in response was noticed between RT and systemic therapy. Before treatment 21% and after treatment 15% of the patients could not walk. The one year survival was 42%. The ambulatory status at presentation was the most important prognostic factor. Examination of the spinal fluid, obtained at myelography, disclosed meningeal carcinomatosis in 9% of the patients. Imaging of the whole spinal canal with cytological examination of the spinal fluid is recommended in breast cancer patients suspected of epidural tumour with features of radiculopathy or myelopathy, irrespective of further clinical data and plain spinal radiographs.

Adult

The need for immediate monitoring of treatment parameters and uniform assessment of patient data in clinical trials. A quality control study of the EORTC Radiotherapy and Lung Cancer Cooperative Groups.

A quality control study was performed during the EORTC phase III study 08844: radiotherapy combined with low dose cisplatin (cDDP) in inoperable non-metastatic non-small cell lung cancer. Radiation alone (55 Gy, split course) was compared to radiotherapy with 30 mg/m2 cisplatin once a week and to radiotherapy with 6 mg/m2 cisplatin daily. The purpose of the control study was to check to which degree protocol guidelines were followed and to measure the extent of differences in assessment of tumour response, recurrence and toxicities between the individual institutes. A review team, consisting of a data manager, a diagnostic radiologist, a chest physician and two radiotherapists reviewed entry criteria, treatment data, tumour responses, recurrences and late toxicity of 177 patients (a total of 300 patients was required for the trial). Only departments which had entered more than 5% of this number of patients were visited. There was a 15% difference in T staging of the patients and a 17% discrepancy in N stage scoring between the review team and the local investigators. Radiotherapy field sizes were insufficient in 15% of the eligible patients during a period of the radiotherapy; in another 17% patients the tumour free margin was less than 1 cm. Radiation doses were incorrectly given to 7% of the patients. The given doses of cisplatin deviated in 10% of the patients treated with combined modalities. The interpretation of chest X-rays and computed tomography (CT) showed important differences in tumour response, tumour recurrence and late toxicity. From these data it is concluded that immediate checks can detect errors in treatments as planned at the local level and will make corrections possible at an early stage in multicentre studies. The quality of trial results will thus be improved. Uniform assessment of treatment outcome, tumour progression and forms of toxicity will lead to more sound trial conclusions.

Carcinoma, Bronchogenic

Squamous cell carcinoma of the penis: accuracy of tumor, nodes and metastasis classification system, and role of lymphangiography, computerized tomography scan and fine needle aspiration cytology.

Among 118 patients with squamous cell carcinoma of the penis treated at our cancer institute between 1956 and 1989, we analyzed the accuracy of classification, using the tumor, nodes and metastasis system. We analyzed the role of lymphography, computerized tomography and fine needle aspiration cytology as additional staging procedures. The primary tumor (T category) was classified incorrectly in 26% of the cases. Overstaging was noted in 10% of the cases because of unsuspected infiltration and overstaging was noted in 16%. Overstaging occurred because of edema and infection masking the actual size and giving a misconception of infiltration, and also because of primary presentation as large exophytic tumors with no or minimal histopathological infiltration. When the regional lymph nodes were categorized simply as positive or negative 80% of the tumors were classified correctly and 20% incorrectly (13% were false positive and 7% were false negative). Regional lymph node invasion that escaped clinical examination was not detected by any imaging examination or fine needle aspiration cytology study. Positive findings were found only in patients with clinically suspected nodes. The classification of regional nodes by clinical examination only is hardly improved by additional imaging studies. Clinical decisions with respect to the management of regional lymph nodes should not be based on negative findings of lymphangiography, computerized tomography or fine needle aspiration cytology. In patients with proved metastasis additional imaging may be of some help in the detection of pelvic node invasion and the determination of the extent of involvement. We recommend lymphangiography as the examination of choice.

Adult

Intravenous contrast in spinal computed tomography to identify epidural metastases.

In 16 patients with spinal epidural metastases from various neoplasms the usefulness of intravenous (IV) contrast injection in spinal computed tomography (CT) scanning was analyzed for determining the presence and extent of the epidural lesion. In all cases enhancement of the epidural tumor mass occurred, which effectively showed the outline of the lesion. The extent of the epidural metastases in the spinal canal was equally well visualized as by myelography. Compared to spinal CT scanning without contrast administration, all IV contrast enhanced CT scans were clearly superior in demonstrating epidural metastases. Intravenous contrast in spinal CT-scanning appears to add relevant information and seems a useful and simple method to define the extent of the epidural tumor. It should be considered in patients where myelography is contraindicated and it may be a valuable method when the response of the epidural tumor to treatment must be determined.

Contrast Media

Multiple spinal epidural metastases; an unexpectedly frequent finding.

In a prospective study, patients with known malignant disease who were suspected of having a spinal epidural metastasis, had myelography which was not confined to the clinically suspected site, but included at least the whole lumbar and thoracic spinal canal. Fifty four of the 106 myelograms revealed at least one epidural metastasis. Twelve of these 54 myelograms showed two separate lesions, and four myelograms showed three separate lesions. In all 16 cases with multiple lesions at least one of the lesions was asymptomatic at the time of the diagnosis. It is concluded that multiple spinal epidural metastases are of common occurrence and occur in about one third of the cases. This finding may have important clinical implications. Examination of the spinal canal for epidural metastases should not be confined to the clinically suspected site, but should include as extensive an area as possible of the spinal canal, whatever technique is to be used.

Adult

Effective systemic therapy for spinal epidural metastases from breast carcinoma.

A complete resolution of spinal epidural metastases following systemic therapy, consisting of chemotherapy and/or hormonal therapy, is reported in four patients with breast carcinoma. Remissions were of substantially longer duration than previous remissions induced by radiotherapy. Single systemic therapy is an underestimated way of treatment for spinal epidural metastases. This way of treatment should be considered when radiotherapy has failed. Under certain circumstances it might even be considered as primary treatment. The protracted remissions following systemic therapy, even in the case of a complete myelographic block, warrant further clinical studies concerning this mode of treatment.

Adult

Model studies at mechanical aortic heart valve prostheses--Part I: Steady-state flow fields and pressure loss coefficients.

In a 3:1 scaled model of the human aorta models of the Omniscience, Björk-Shiley Convexo-Concave, Björk-Shiley Monostrut, Medtronic-Hall, Duromedics (Hemex) and the Saint Jude Medical heart valve prostheses are studied in steady flow representing the systolic peak flow phase. Detailed flow visualization experiments show flow separations at all inner ring surfaces as well as at most of the occluders. The resulting stagnation areas increase the risk of thrombus accumulation. Flow separations also stimulate vortex formation and turbulent mixing at the downstream jet boundaries and thus may intensify blood damage by turbulent shear stresses. The different influences of struts and occluder guides on the flow around the occluders are discussed. The effects of the individual valve components on the flow fields are analyzed and correlated with the resulting pressure losses.

Aortic Valve

Dural and direct cavernous sinus fistulas.

Fistulas between the cavernous sinus and the carotid artery occur either after trauma or spontaneously. Unilateral exophthalmos is invariably the most conspicuous symptom. Until recently, treatment consisted of some method of occluding the carotid artery involved. Interventional catheter techniques have since been developed that use either Gelfoam embolization or released balloons. The results seem very promising, but long-term results of these new techniques are not yet available. Carotid-cavernous sinus fistulas may be dural or direct, each requiring a different interventional technique. Theredore, it is essential to determine the type involved by selective internal and external carotid angiography. This paper discusses 19 patients with carotid-cavernous fistulas, four of whom were successfully treated by catheter techniques. Gelfoam embolization was used in one case, and in three cases the fistula was closed with the aid of a balloon.

Adolescent

The value of computer tomography, orbital venography and carotid angiography in the diagnosis of exophthalmos.

On the bases of 25 patients examined by orbital venography, computer tomography, (CT scanning) and sometimes carotid angiography, the diagnostic value of each of these methods is evaluated. The data obtained are compared with the corresponding information from the literature. In view of the findings it can be stated that CT scanning can be regarded as the primary neuroradiological examination in cases of exophthalmos. Orbital venography gives supplementary information in cases of varices and venous malformations. Angiography is the method which supplies the maximum of information when cavernous sinus fistulae are clinically suspected. With reference to 3 patients it is explained that in such selective angiography of the internal and external carotid and the vertebral artery is indicated.

Adolescent