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J Zwartendijk

Publications and source records attributed to J Zwartendijk.

34 records · Page 2Linked to original sources
PubMed1990

Sensitivity and specificity of acid phosphatase to detect prostate cancer using data from a hospital information system.

Indices of diagnostic tests, such as sensitivity and specificity, should be determined using diagnostic test results of patients tested in clinical practice. Hospital information systems that store data on diagnostic tests and diagnoses might be used for sampling the desired study population and in the actual process of collecting the data. This paper presents, as an example, a study calculating the sensitivity and specificity of the prostate-specific acid phosphatase test. All data needed in the study were obtained from the hospital information system of Leiden University Hospital. The final health status of each patient was assessed by the cancer registry of the system. The reason for ordering the test was deduced from data on histopathological examinations of prostatic tissue. The actual selections made from the central database are described in dataflow diagrams. The sensitivity of the test was found to be 0.34 and the specificity 0.88, using a discrimination value of 1.00 U/l. The impact of the reason for ordering the test on the specificity is illustrated. Possible biases of these measured values are discussed.

Acid Phosphatase↗
PubMed1988

Relationship between DNA ploidy, antigen expression and survival in renal cell carcinoma.

Tumor ploidy and expression of renal differentiation antigens as recognized by a previously described series of monoclonal antibodies (MAbs) (RC2, RC3, RC4, RC38, RC69, RC154 and G250) were assessed in 48 renal-cell carcinomas. A positive association was found between aneuploidy and development of metastases. Aneuploid tumors showed a loss of antigen expression more frequently than diploid tumors. This difference was statistically significant for antigens recognized by RC3 and RC69. Loss of RC154 reactivity was associated with increased metastatic potential. Clinical stage was the most powerful single prognostic variable but ploidy and RC3 reactivity carried additional prognostic information.

Actuarial Analysis↗
PubMed1987

Autologous anticancer antigen preparation for specific immunotherapy in advanced renal cell carcinoma.

33 patients with metastatic renal cell carcinoma were treated intradermally with an autologous (29 patients) or allogeneic (4 patients) irradiated tumor cell preparation mixed with Corynebacterium parvum given monthly after palliative nephrectomy (27 patients) or excision of tumor metastases (2 patients). No significant toxicity was produced. 8 patients (24%) underwent objective responses. Responding patients had a median survival of 32 months, the median survival of all patients was 17 months (differences not significant).

Actuarial Analysis↗
PubMed1986

Monoclonal antibody G 250 recognizes a determinant present in renal-cell carcinoma and absent from normal kidney.

This report describes a monoclonal antibody designated G 250, subclass IgGl, that recognizes an antigen preferentially expressed on cell membranes of renal-cell carcinoma cells (RCC) and not expressed in normal proximal tubular epithelium. G 250 antibody reacted with 46 of 47 primary RCC, with 7 of 8 RCC metastases and with a few other malignant tumors. The staining pattern of G 250 differs from that of other RCC-related antibodies described. Preliminary experiments show that this antibody can be used to visualize RCC xenografts in nude mice by immunoscintigraphy.

Animals↗
PubMed1986

Connective tissue stroma in bladder papillary transitional cell carcinoma, carcinoma in situ and benign cystitis.

The stromal characteristics in papillary and non-papillary tumours of the urinary bladder were investigated in an attempt to improve the accuracy of histopathological diagnosis. It appeared to be possible to differentiate true papillary tumours from pseudopapillary structures lined by carcinoma in situ. Stromal differences were not found in cases of carcinoma in situ accompanied by denuding cystitis and cystitis due to other aetiological factors. It is concluded that histopathological examination of the stroma of bladder tumours improves diagnostic accuracy.

Alcian Blue↗
PubMed1986

Immunohistochemical analysis of monoclonal antibodies to renal antigens. Application in the diagnosis of renal cell carcinoma.

Four mouse monoclonal antibodies reacting with renal proximal epithelium were characterized on normal adult tissues, fetal kidneys, and various malignancies. These four antibodies were found to react with renal cell carcinomas (RCCs) but not with a variety of other tumors. Three antibodies react only with some primary RCCs and not with metastatic RCCs. The fourth antibody, RC 38, reacts with 46 of 47 primary RCCs tested and with 8 of 13 RCC metastases. No reaction was seen with 179 tumors of various origin, which indicates that this antibody is very useful in diagnosing RCC.

Adenoma↗
PubMed1981

Extracorporeal renal surgery.

By means of techniques derived mainly from renal transplant surgical experience, several pathologic conditions of the renal artery, the kidney and the ureter have been made accessible to surgical therapy in the course of the past two decades. This therapy is basically composed of nephrectomy, workbench surgery and reimplantation of the kidney, in this order, and called "extracorporeal renal surgery'. Indications for its use are proposed and discussed, and the operative technique is described. Results are presented of 27 extracorporeal vascular reconstructions in 25 patients with severe renovascular hypertension on the basis of fibromuscular dysplasia located predominantly peripherally in the renal artery and its branches. Of these procedures, 25 were actually completed since in two patients reconstruction of the renal artery was technically impossible and reimplantation of their kidneys had to be discarded. One out of the other 23 patients died because of haemorrhagic and septic complications. In the remaining group of 22 patients, operation-associated complications were observed in one patient, who had to be reoperated because of bleeding at the operation site. At a mean follow-up period of 4.5 years, all these 22 patients had normal blood pressures, and 16 were off medication ("cured') whereas six needed only moderate anti-hypertensive medication ("improved'). Results are also presented of extracorporeal procedures performed in one patient with a carcinoma in a solitary kidney and in one patient with a ruptured aneurysm of the abdominal aorta in which both renal arteries were involved. Both patients are well at one and more than five years postoperatively, respectively.

Adolescent↗
PubMedDate not supplied

The value of pretreatment clinical and biochemical parameters in staging and prognostic stratification of patients with newly diagnosed prostate carcinoma.

PURPOSE: To determine whether it is possible to select patients in whom and for what reason bone scintigraphy should be performed or not, a retrospective study was performed of 161 consecutive patients with newly diagnosed prostate cancer. MATERIALS AND METHODS: Follow-up varied from 1 to 88 months during which 67 patients died. Bone scans were classified from 0 (= normal) to 3 (typical pattern of metastases) and were correlated with age, alkaline phosphatase (AP), prostate specific antigen (PSA), tumor grade, TNM-stage and survival. For survival, 68 patients who were not referred for bone scintigraphy were also evaluated. RESULTS: All parameters demonstrated a correlation with the incidence of a positive bone scan, but PSA was the best overall predictor in this (p < 0.0001). None of the patients with PSA < or = 20 ng/ml (n = 64) showed metastases, whereas 8 of 9 patients with PSA > 1000 ng/ml and patients with PSA values between 20 and 1000 ng/ml in combination with AP > 90 U/L (n = 24) had bone metastases. Furthermore, a class 3 bone scan was found to be the most important parameter in assessing prognosis and survival (p < 0.0001), whereas no differences were found in patients with a class 0, 1 and 2 scintigram. CONCLUSIONS: For staging and prognostic stratification purposes, bone scintigraphy and additional roentgenograms are of value in a selected group of patients. In contrast with a typical pattern of metastases on bone scintigraphy, an abnormal scan (class 1 and 2) at the time of diagnosis is not a poor prognostic parameter of the risk of death. Bone scintigraphy can be omitted in patients with PSA values < 20 ng/ml. In patients with PSA levels > 1000 ng/ml or less increased levels combined with alkaline phosphatase levels > 90 U/L, bone scintigraphy seems to be of no value in staging disease.

Aged↗
PubMedDate not supplied

Urinary cytology in renal transplant recipients with stable graft functions.

The utility of routine urinary cytology in renal transplant recipients was investigated. Slides of 79 urine samples obtained from 59 renal transplant patients shortly after transplantation and of 275 urine sediments from 126 patients who had received a transplant before 1978 were screened for abnormal urothelial cells. None of the samples taken within one year of transplantation contained malignant cells. For five patients transplanted before 1978, repeated cytologic examinations showed malignant cells, but neither urologic examination nor clinical nor postmortem follow-up studies revealed a tumor. In all five cases, the abnormal cells disappeared from repeat samples within two to three months. None of the other 121 patients, with repeatedly normal urinary cytologies, exhibited a urinary tract carcinoma in the 24-month follow-up period. It would appear that the cytologic findings in the urine of renal transplant patients who have received long-term immunosuppressive medication may be transiently abnormal.

Female↗
PubMedDate not supplied

Carcinoma in situ of the urinary bladder. Clinical presentation, cytologic pattern and stromal changes.

The clinical presentation, cytologic pattern and stromal changes in the cystectomy specimen were studied in a group of 26 patients with carcinoma in situ of the urinary bladder who underwent cystectomy. Only cases in which the nuclear area of the carcinoma in situ cells was over 80 sq micron (large-cell type) were included in this study. The results indicate that the cells from large-cell carcinoma in situ of the bladder exfoliate easily, resulting in a cytologic pattern of predominantly single, highly abnormal cancer cells. Due to the increased exfoliation of the affected epithelium, the bladder stroma is focally denuded; therefore, while cytology may be strongly positive for malignancy in these cases, the histologic diagnosis can be falsely negative when only denuded stroma is biopsied. The edematous stroma causes complaints of "cystitis." The neoplastic urothelium may involve contiguously related epithelial surfaces. When the lesion extends into the prostatic ducts, the patient can have "pseudoprostatitis" complaints. Urethral extension may give penile voiding pain. In one female patient, involvement of the vagina and vulva was found. Carcinoma in situ may develop in patients with papillary low-grade bladder carcinoma during follow-up, with a concomitant shift in the cytologic and clinical patterns; this deserves the consideration and attention of the cytologist and the clinician due to its serious clinical implications.

Adult↗