Diagnostic value of 169Yb-cis-dichlorodimethionine platinum scintigraphy in patients with malignant lymphomas.

Ytterbium-169 (169Yb) cis-dichlorodimethionine platinum (169Yb-PtCl2Meth2) is a new agent of low toxicity with an affinity for neoplastic tumours. The aim of this study was to assess the diagnostic value of 169Yb-PtCl2Meth2 scintigraphy in patients with malignant lymphomas. 169Yb-PtCl2Meth2 scintigraphy was performed in 67 patients with histologically proven malignant lymphoma. Liver, spleen, kidney and bone were among the normal tissues that showed uptake of the radiopharmaceutical. The compound is excreted in the main through the urinary tract. There was no significant activity in the bowels. For evaluation of the images, uptake of activity was scored according to a 5-point scale. In total, 888 sites were evaluated. The sensitivity, specificity and accuracy of lymphoma detection for the body as a whole was 80, 89 and 87%, respectively. The best results were obtained for the head (sensitivity 91%, specificity 89%), neck (sensitivity 84%, specificity 90%) and chest (sensitivity 82%, specificity 84%). In the sub-diaphragmatic region, sensitivity and specificity were 76 and 84%, respectively. Scintigraphy with 169Yb-PtCl2Meth2 appears to be a sensitive, non-invasive procedure for the staging of malignant lymphomas. The results suggest that it is possible to monitor the therapy of malignant lymphoma by means of 169Yb-PtCl2Meth2 scanning.

[Usefulness of biliary scintigraphy using technetium Tc 99m mebrofenin for detection of disorders of patency of the bile ducts]. / Przydatnosc cholescyntygrafii przy uzyciu 99mTc-mebrofeniny do wykrywania zaburzen droznosci dróg zólciowych.

The value of the dynamic 99mTc-mebrofenin liver scintigraphy in the diagnosis of extrahepatic bile ducts patency has been assessed. The study included 176 patients in whom an occlusion of bile ducts of any degree was excluded in 111 cases, and bile ducts patency disorders were diagnosed in 65 patients. Time of the appearance of radiolabelled mebrofenin was measured in the selected segments of bile ducts. Time of appearance of radioactivity in the intestines was also noted. Another diagnostic criterion was persistent stasis of radioactivity in the choledochus. Basing on these criteria, patients were classified as "sick" or "healthy". It was possible to exclude the disease in case of negative result with the probability level of 91%. Positive result of scintigraphy points to the impaired patency diagnosis with 96% probability. Technique is simple, free of complications and contraindications. It is also of high predictive value. These features make the procedure particularly useful in the diagnosis of bile ducts patency.

Effects of vinyl chloride on liver function of exposed workers, evaluated by measurements of plasma clearance of the 99mTc-N-2,4-dimethylacetanilido-iminodiacetate complex.

In 77 males exposed occupationally to vinyl chloride (VC), the plasma clearance (Cl) of 99mTc-N(2,4-dimethylacetanilido)iminodiacetate ('HEPIDA' complex) was determined. The results were juxtaposed with a scaled assessment of liver parenchyma performance based upon clinical examination and a series of biochemical tests. Detection of the diagnosable damage of liver parenchyma by means of the reduced clearance was sensitive (90%) at the reasonable specificity of 74%. Probability of exclusion of liver damage in patients with the clearance above 240 ml min-1 1.73 m-2 amounted to 92%. There was a significant correlation between degree of exposure to VC and the frequency of low clearance values. It appears that the periodic determination of the 99mTc-HEPIDA clearance in workers exposed to VC allows the assessment of incipient liver damage and signals the need for prophylactic measures.

[Evaluation of the effect of a new polyfungin derivative in chronic infection of albino mice with P-32 labeled Candida albicans]. / Próba oceny dzialania nowej pochodnej polifunginy w przewleklym zarazeniu bialej myszy Candida albicans znakowanej 32P.

White mice, Balb/c, were infected intraperitoneally with Candida albicans strains: standard ATCC 1023 and 910 strain isolated from vaginal excretions of patient suffering from genital mycosis. One group of animals was given new Polish polyene antibiotic N-methylglucamine salt of N-glucosylpolyfungin (N-MGP). It was possible to follow a course of infection using our own experimental model of candidiasis with 32P-Candida albicans cell suspension by measuring a degree of radioactivity of organs taken from treated and untreated animals. Statistically significant lower radioactivity values (P less than 0.01) were found in organs of animals treated with N-MGP salt for 20 days in daily dose of 20 mg/kg of body weight. Therapeutic efficacy of N-MGP salt was confirmed in separate experiments where mice were infected intraperitoneally with unlabelled Candida albicans cells. Negative results of mycological examinations were found when several organs homogenates of treated mice were tested. Activity of new polifungin derivative in chronic candidiasis of mice was found using two different ways of evaluation of this new preparation.

Radiation doses from 51Cr-bleomycin.

Extensive studies were made of long-term whole-body retention, plasma concentration, urinary excretion and organ retention of 51Cr in rats after intravenous injection of 51Cr-bleomycin. A similar but less extensive investigation was performed on rabbits, and whole-body retention, plasma concentration and urinary excretion was also followed in patients given 51Cr-bleomycin for diagnostic purposes. From an analysis of the collected information it followed that integrated whole-body and organ retention, corrected for radioactive decay, is similar in man and rabbit, and higher by a factor of about 2 in the rat. Doses to organs and whole body in man were calculated using the MIRD methodology and assuming conservatively that the kinetic data derived in rats are applicable to man. The organ and whole-body MIRD doses after 51Cr-bleomycin administration are comparable to those after 67Ga-citrate and the effective dose equivalent from a diagnostic amount of 740 MBq of the 51Cr complex amounts to about 6 mSv. However, the subcellular distribution in the liver of 51Cr, administered in the form of 51Cr-bleomycin, indicated a significant enrichment of 51Cr in the nuclei and in the DNA over mean concentrations in the liver cells. Also, the quality factor for Auger electrons, emitted by 51Cr, when assessed on the basis of the Q vs. LET relationship, as proposed by ICRP, was substantially higher than unity. Doses calculated for cell nuclei and the DNA in the liver cells were higher than the cell-averaged values by a factor 2.5 and 5, respectively, and the corresponding dose equivalents by a factor of 9 and 24. The effective dose equivalent, estimated on the basis of dose equivalents to cell nuclei and the DNA, amounted to 33 and 83 mSv per examination (740 MBq of 51Cr-bleomycin), respectively.

51Cr-bleomycin in the diagnosis of tumours of the chest.

51Cr-bleomycin was used for the scintigraphic diagnosis of primary and secondary tumours of the thorax. The study was based on observations in 104 patients. The scintigraphy was performed using a gamma camera coupled to an on-line computer. Active lesions were scored using a semiquantitative scale of scores 0 to 5. Images were subdivided into 222 regions considered. In 72 of these, the presence of disease was diagnosed (64 malignant, 8 non-malignant) and 150 regions were classified as free from disease. At the decision threshold of score 2, over-all sensitivity and specificity of the scintigraphic detection of malignant tumours amounted to 97 and 79%, respectively. Inflammatory changes displayed some detectable accumulation of 51Cr-bleomycin but scores attributed to these lesions did not exceed the value of 2.

51Cr-bleomycin, a new oncophilic radiopharmaceutical. II. Scintigraphic diagnosis of malignant neoplasms.

51Cr-bleomycin was used for the scintigraphic detection of tumours and the assessment of the spread of the disease in 20 patients with various malignancies: 7 with Hodgkin's lymphoma, 5 with other malignant lymphomas, 4 cases of cervix carcinoma and 4 other tumours. The scintigraphy was performed using a Toshiba GC 401 gamma camera coupled to an MDSI computer Trinary. Active foci were scored using a semiquantitative scale of 0 to 5. Results of these studies were compared with those of tests similarly carried out with 57Co-bleomycin (in 9 of the cases) and 67Ga-citrate (11 cases); they demonstrated that the properties of 51Cr-bleomycin for scintigraphic detection of neoplastic foci are similar to those of 57Co-bleomycin.