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H Schraffordt Koops

Publications and source records attributed to H Schraffordt Koops.

At least 109 records · Page 6Linked to original sources
PubMed1992

Surgical quality control in an international randomized clinical trial.

One of the current international prospective clinical trials of the EORTC Melanoma Cooperative Group explores the usage of regional isolated perfusion as adjuvant in melanomas located on the extremities. In the design of the study it is necessary to define not only the extent of the surgery (perfusion+local excision versus local excision only), but also to ensure uniformity of surgery performed between surgeons and institutions. With on-site visits and general meetings with the participants, surgical protocol violations and misinterpretations of the protocol could be avoided. The conclusion is that accurate surgical quality control is time consuming, but not difficult.

Chemotherapy, Adjuvant↗
PubMed1991

Intestinal hemorrhages in patients with a nonseminomatous testicular tumor.

This article reports on three patients with intestinal bleeding due to metastases from a nonseminomatous testicular tumor (NSTT) to the gastrointestinal tract. Involvement of the gastrointestinal tract is rare. The mode of spread is either by hematogenous dissemination or by direct extension from involved paraaortic lymph nodes. The symptoms of these patients are briefly described. Early recognition and efficient supportive care are essential in the management of such patients.

Adult↗
PubMed1991

TRA-1-60: a new serum marker in patients with germ-cell tumors.

TRA-1-60 is a monoclonal antibody (MAb) that recognizes a mucin-like antigenic determinant expressed on the surface of embryonal carcinoma (EC) progenitor cells. In order to determine whether this antigen is released into the serum of patients with a non-seminomatous germ-cell tumor (NSGCT), we developed a sensitive 2-step immunoenzymometric assay. Of 42 EC-positive NSGCT patients tested, 32 (76%) were found to release TRA-1-60-reactive antigen into their serum, in contrast to 1 positive finding in 10 EC-negative NSGCT patients. The marker was found in 67% (10/15) of the EC-positive patients who were negative for both AFP and HCG. Sera from seminoma patients did not contain elevated levels of the TRA-1-60 antigen. Therefore, we propose that the TRA-1-60 antigen is a useful additional serum marker for following the progress of NSGCT(EC+) patients.

Antigens, Neoplasm↗
PubMed1991

MRI and CT in the preoperative evaluation of soft-tissue tumors.

The value of MRI and CT in the diagnosis of soft-tissue tumors was investigated in a prospective study of 25 patients. MRI and CT give a true reflection of the tumor dimensions. It is impossible, however, to make a reliable diagnosis with either technique. If both techniques are available, then MRI is to be preferred in view of the better spatial orientation and sharper contrast it offers between the tumor and adjacent structures. If only CT is available, then an adequate image can generally be obtained with this technique too.

Adolescent↗
PubMed1991

Complete association of loss of heterozygosity of chromosomes 13 and 17 in osteosarcoma.

Mutations of the retinoblastoma (RB1) gene are not confined to retinoblastoma, but are also involved in the development of osteosarcoma. Structural aberrations within the RB1 gene have been studied in fresh samples of eleven cases of osteosarcoma. In five cases a rearrangement was detected, one of which was best explained as a partial duplication. The chromosomal mechanisms by which the nonmutated RB1 allele was lost appeared to be similar in frequency to those that have been reported for retinoblastoma. Loss of heterozygosity was observed for chromosomes 3, 11, 13, 17, and 22. However, when no loss of heterozygosity of chromosome 13 was detected, the other chromosomes retained their heterozygosity as well. A complete association of loss of heterozygosity of chromosomes 13 and 17 was observed. This can be taken as an indication of the involvement of another tumor suppressor gene at chromosome 17 in the initiation of osteosarcoma.

Adolescent↗
PubMed1991

Haematogenous tumour growth in the inferior vena cava in a patient with a nonseminomatous testicular tumour.

The case history is reported of a patient with an invasion of the inferior vena cava by metastases of a non-seminomatous testicular tumour. He was treated with combination chemotherapy, followed by laparotomy and resection of residual tumour tissue. Fourteen months after this operation he is in good health. For every retroperitoneal lymph node dissection it is necessary to be on the look-out for invasion of the vena cava, because of the risk of a sudden pulmonary embolism.

Adult↗
PubMed1991

Dual parameter flow cytometry for deoxyribonucleic acid and intermediate filament proteins of residual mature teratoma. All tumor cells are aneuploid.

Most testicular germ cell tumors of adults are presumably derived from polyploid carcinoma in situ. Thus, one would expect that even highly differentiated teratoma components are aneuploid and that it is unlikely to find diploid tumor cell (sub)populations. We studied 10 residual mature teratomas (RMTs) using a dual parameter flow cytometry procedure. Nuclear DNA was stained with propidium iodide and cytoplasmic intermediate filament proteins, in particular, cytokeratins, with fluorescein isothiocyanate-labeled specific monoclonal antibodies. Cells in RMTs, immunoreactive with antibodies to cytokeratins were considered to be tumor cells. These were always found to be aneuploid, in agreement with the available cytogenetic data on these tumors. The diploid cells present in RMTs were devoid of cytokeratins; therefore, these cells represent the nonmalignant normal host stromal and inflammatory cells. These results, in accordance with our earlier finding, indicate that diploid testicular germ cell tumors are extremely rare in adults, and that even the histologically benign somatic tissues in RMT after polychemotherapy are aneuploid.

Adult↗
PubMed1990

Sarcoid reaction mimicking intrathoracic dissemination of testicular cancer.

The close observation of patients treated for testicular cancer led to the suspicion of intrathoracic and/or mediastinal metastases on radiologic examination in a number of patients without other evidence of relapse. This report presents two patients with combined seminomatous and nonseminomatous germ cell tumors with isolated sarcoid reactions of hilar and interlobular lymph nodes, detected concomitant with diagnosis and 12 months after diagnosis, respectively. Histologic examination appears to be imperative in these cases to avoid unnecessary chemotherapy.

Adult↗
PubMed1990

[Adjuvant regional isolation perfusion of the extremities of patients with stage I melanoma thicker than 1.5 mm].

The use of isolated regional perfusion with melphalan as an adjuvant treatment for stage I melanoma of the extremity continues to be controversial. The present retrospective study evaluates the past 25 years' experience by comparing 227 perfused patients from Groningen with 238 matched controls from five hospitals in The Netherlands and Westphalia (West Germany). All patients underwent wide local excision for a primary extremity melanoma of 1.5 mm or greater in thickness. A proportional hazards regression analysis for recurrence of disease and survival identified the significant prognostic factors, of which, besides level of infiltration, ulceration, age and sex, tumour thickness was found to be the most important. Corrected for these factors, it was not possible to demonstrate a statistically significant effect for perfusion in terms of time to limb recurrence (p = 0.61), time to regional lymph node metastasis (p = 0.11), time to distant metastasis (p = 0.73), disease-free interval (p = 0.42), and survival (p = 0.90). No statistically significant differences were seen for adjuvant perfusion in any of the subgroups.

Adult↗
PubMed1990

Chromosomal damage in peripheral blood lymphocytes of patients treated for testicular cancer.

We describe the presence of a large number of chromosome aberrations in lymphocytes of 50 patients with testicular cancer. These chromosomal aberrations were not only found in patients treated with chemotherapy but also in untreated patients or in patients after surgery alone. Our results suggest a role for genetic instability in the pathogenesis of testicular cancer. This instability might be a risk factor for the development of secondary malignancies.

Adult↗
PubMed1990

Phase II study of carboplatin and cytosine arabinoside in patients with disseminated malignant melanoma.

Twenty-one patients with disseminated malignant melanoma were treated with a combination of carboplatin and cytosine arabinoside. Two complete and three partial remissions occurred. No complete cross-resistance was found with a regimen containing 5-(dimethyltriazeno)imidazole-4-carboxamide (DTIC) in two patients. It is suggested that this regimen might be studied further as a second-line treatment for patients who fail on DTIC-containing treatment.

Adult↗
PubMed1990

An extendable modular endoprosthetic system for bone tumour management in the leg.

A modular endoprosthetic system has been developed at the Groningen University Hospital and the University of Twente. The system can bridge a defect resulting from the resection of a malignant bone tumour which has developed around the knee joint of a child. Since the other healthy leg continues to grow, the system includes an element whose length can be adjusted non-invasively by using an external magnetic field. In addition to this lengthening element, there are one hip and two knee components, connectors of various lengths, and fixation elements. The paper describes the elements of the modular endoprosthetic system. Tables are created by means of which the elemental composition of such an endoprosthesis can be determined for each individual patient.

Adolescent↗
PubMed1990

Cytogenetics of carcinoma in situ of the testis.

Carcinoma in situ (CIS) of the testis is the precursor lesion of most testicular germ cell tumors (TGCTs). Karyotyping of CIS is important for a better understanding of the pathogenesis of TGCTs and the progression to invasive cancer. We karyotyped three cases of CIS. All three cases showed a numerical abnormal chromosomal pattern. In one case, two copies of the germ cell tumor marker i(12p) were found.

Adult↗
PubMed1990

Alpha-fetoprotein-lectin binding as a marker of tumour activity or liver damage.

To establish whether alpha-fetoprotein (AFP) produced in the early post-treatment phase of a patient with a germ cell tumour of the testis or the ovary originates from the tumour or is due to an underlying disturbance in liver function, the binding of AFP to concanavalin A (Con A) was investigated as a discriminative variable. A two-step assay is described that can distinguish the type of AFP produced at levels as low as 10 ng/ml. A Con A-binding ratio of 12-43% was found in the patients with disseminated germ cell tumours and in patients with AFP-positive gastrointestinal carcinomas. AFP from the liver gives ratios below 10%.

Biomarkers, Tumor↗
PubMed1989

Dedifferentiated parosteal osteosarcoma of the femur with aneuploidy and lung metastases.

In this report, the pathologic findings and the results of cellular DNA measurements of a tumor that on first presentation seemed to be a classical parosteal osteosarcoma are described. After resection 8 months later, part of the tumor appeared to display highly malignant features. DNA flow cytometry of this part of the tumor showed an aneuploid cell population. The aggressive nature of the tumor was confirmed by the development of lung metastases approximately 1 year after resection of the primary tumor.

Adult↗