Prediction of long-term gonadal toxicity after standard treatment for testicular cancer.

Long-term post-treatment gonadal toxicity was examined (median 3 years after treatment discontinuation) in 125 testicular cancer patients treated with standard regimens: no radiotherapy or chemotherapy (36 patients), infradiaphragmatic radiotherapy (38 patients), and 3-4 cycles of cisplatin-based chemotherapy (51 patients). Radiotherapy and chemotherapy had no impact on serum testosterone, but led to a slight increase in serum follicle-stimulating hormone (FSH). The lowest median value of post-treatment sperm cell count was observed after infradiaphragmatic radiotherapy, the highest value after standard chemotherapy. After more intensive cytotoxic treatment recovery of the gonadal function seemed to be delayed. In testicular cancer long-term post-treatment gonadal toxicity is correlated to the patient's pretreatment gonadal function and age rather than to the standard treatment of the malignancy. In patients with pretreatment normal gonadal function the risk of permanent treatment-induced toxicity is minimal after present standard treatment.

Continuous intravenous interleukin-2 infusion and subcutaneous interferon-alpha in metastatic renal cell carcinoma.

In a phase II trial patients with metastatic renal cell carcinoma (MRCC) received two induction cycles each consisting of 24-h intravenous infusions of interleukin-2 (IL-2) 18 x 10(6) U/m2/day and interferon (IFN) 3 x 10(6) U/m2/day given subcutaneously on days 1-5 and 8-12 of a 2-week cycle. Between cycles 1 and 2 there was a 3-week treatment-free interval. Maintenance therapy consisted of four monthly cycles of IL-2 and IFN. Due to considerable toxicity the trial was prematurely closed after inclusion of 16 of 23 scheduled patients. Three partial responses were observed. Nine events of severe or life-threatening side-effects occurred and 8 patients were transferred to the intensive care unit. The combination of continuous intravenous high-dose infusions of IL-2 and subcutaneously given IFN is moderately effective, but too toxic for routine treatment of MRCC.

Follow-up of breast cancer patients stage I-II: a baseline strategy.

In 430 stage I-II breast cancer patients the cost-benefit of investigations during follow-up have been studied. Median follow-up time was 8 years and 128 patients had relapsed, 91 with metastatic disease. High costs of routine chest X-ray, limited skeletal X-ray and bone scan examinations were associated with low incidence of diagnosed relapses not suspected otherwise. In the eight blood analyses examined, increases of more than 10 mm/h in erythrocyte sedimentation rate (ESR), 20 U/l in gamma-glutamyltransferase (GT) or 60 U/l in alkaline phosphatase (ALP) resulted in a combined sensitivity of 55% and specificity of 91% for relapses with distant metastases. Elevation of at least two blood tests gave a combined sensitivity of 31% and a specificity of 98%. The importance of using individual reference values in screening for recurrences is emphasised. Symptomatic relapse or relapse detected at interval visits were not independent prognostic factors. The blood tests ALP, ESR and GT were strong predictors of survival measured from relapse which increase their legitimacy in follow-up. A more frequent follow-up for patients with 4+ involved nodes is proposed: three visits annually the first 5 years vs. two visits annually for the others. We conclude that history, clinical examination, ALP, ESR and GT are sufficient as a baseline screening for relapse in breast cancer patients.

Experiences of the Janus Serum Bank in Norway.

The ongoing JANUS project was started in 1973. The serum bank comprises 424,938 serum samples consolidated from 293,692 donors. The specimens are stored at -25 degrees C. From 1 to 13 consecutive samples are available from each donor. Up to October 1993 about 14,000 of the donors had developed some form of cancer. Frozen serum samples collected from a few months to 19 years prior to clinical recognition of their disease are available for research purposes. The principle aim of the JANUS project is to search in the premorbid sera for chemical, biochemical, immunological or other changes that might be indicative of cancer development at early stages. Gas chromatography-mass spectrometry and two-dimensional protein electrophoresis have been used to evaluate the stability of the frozen sera. Some recent findings are: CA-125 may be elevated months prior to the diagnosis of ovarian cancer; serum thyroglobulin may be a preclinical tumor marker in subgroups of thyroid cancer; low levels of selenium in serum reflects increased risk of thyroid cancer; raised antibodies in serum against Epstein-Barr virus is a risk factor for development of Hodgkins disease; prostate-specific antigen may be elevated years prior to clinical diagnosis of prostate cancer; and linoleic acid in serum phospholipids is inversely related to breast cancer risk. The serum bank is, in principle, suitable for environmental studies, e.g., human exposure assessment. The steering committee of the JANUS project is open to suggestions for collaborative research on this topic.

Prediagnostic serum selenium in a case-control study of thyroid cancer.

Sera from 43 persons who developed thyroid cancer on an average 4.8 years after blood sampling were compared with sera from controls. Three controls per case matched for sex, age, place of residence and year of blood sampling, with regard to serum selenium and serum copper. Cases were significantly lower in serum selenium than controls, and the estimated odds ratio of thyroid cancer increased from 1 for levels greater than or equal to 1.65 mumol/l, to 6.1 for levels 1.26-1.64 mumol/l, to 7.7 for levels less than or equal to 1.25 mumol/l. When time from blood sampling to diagnosis of the case was considered, it could be shown that the protective effect of high serum selenium concentrations was restricted to the last (less than 7) years prior to the diagnosis of thyroid cancer. The serum selenium concentration of cases tended to decrease relative to controls the shorter time was from blood sampling to the diagnosis. There was no difference between cases and controls with regard to serum copper.

Recovery of impaired pretreatment spermatogenesis in testicular cancer.

Light microscopic sperm analysis was done 24 months after treatment or later in 25 patients with testicular cancer with azoospermia or severe oligospermia (sperm cell count less than 10 x 10(6)/mL) after orchiectomy before further treatment. Treatment after orchiectomy consisted of abdominal irradiation, cisplatin-based chemotherapy, retroperitoneal surgery, a combination of the former treatment modalities, or a surveillance policy. At the time of post-treatment reassessment, 15 of the 25 patients had sperm cell concentrations of at least 10 x 10(6)/ml (7 of 14 patients in the azoospermia group; 8 of 11 patients in the oligospermia group). Eight patients fathered a child after discontinuation of treatment for testicular cancer. Recovery of spermatogenesis could be seen after all types of treatment. A highly increased pretreatment serum follicle-stimulating hormone was correlated with lack of sperm cell production recovery.

Gamma-Glutamyl-3-carboxy-14-nitroanilide: the substrate of choice for routine determinations of gamma-glutamyl-transferase activity in serum?

Gamma-Glutamyl-3-carboxy-4-nitroanilide has been tested as donor substrate in the assay of gamma-glutamyltransferase activity in serum, glycylglycine being used as acceptor substrate. This donor substrate is highly solube even in neutral solutions, in contrast to the commonly used gamma-glutamyl-4-nitroanilide. The enzyme which apparently acts accordingly to a ping-pong bi bi kinetic mechanism, shows an absolute KM value for gamma-glutamyl-3-carboxy-4-nitroanilide of about 0.64 mmol/l, and for glycylglycine of about 13.4 mmol/l. The former KM value is significantly lower than that previously found for gamma-glutamyl-4-nitroanilide. The carboxyl derivative exhibits a marked competitive inhibitory effect on the gamma-glutamyltransferase. This effect is more pronounced than that of gamma-glutamyl-4-nitroanilide. The carboxyl derivative has somewhat higher absorbance in the range of wave length (400-420 nm) used to monitor the formation of the product. It is concluded that as donor substrate in the assay of gamma-glutamyltransferase activity of serum, the new derivative is not substantially superior to the gamma-glutamyl-4-nitroanilide conventionally used.

Safety and tolerability of iodixanol in healthy volunteers with reference to two monomeric X-ray contrast media.

The low osmolar, non-ionic X-ray contrast media have shown a lower frequency of adverse events than the older ionic ones. In this study changes in routine clinical-chemical parameters in blood and urine, vital signs and adverse events were recorded in six groups of 10 healthy male volunteers receiving either iodixanol, a new non-ionic, dimeric X-ray contrast medium for general vascular use, or one of the two non-ionic, monomeric contrast media iopentol and iopamidol. Minor decreases were observed in the values for haemoglobin, haematocrit and erythrocytes 5 min and 3 days after injection of iodixanol. A minor increase was seen in platelets and total protein after 3 days. A transient increase in serum osmolality was seen 5 min after the injections of iopentol and iopamidol. This was not seen in any iodixanol group. The level of thyrotropin showed an increase in all groups at 3 days. It was back to normal within 21 days. No changes of clinical importance were seen regarding blood pressure, heart rate or ECG in any volunteer. No severe adverse events were reported. All events were of short duration, and of mild or moderate intensity. The results, however, may indicate a lower frequency of adverse events/discomfort after the administration of the dimeric iodixanol than the 2 monomeric contrast media iopentol and iopamidol.

The JANUS serum bank.

The on-going JANUS project was initiated by the Norwegian Cancer Society in 1973. The serum bank comprises close to 0.5 million serum samples collected from 170,000 donors. From 2-16 consecutive samples are available from each donor. The sera are stored at -25 degrees C. At regular intervals the JANUS-collection is matched against the files of the Norwegian Cancer Registry. From 1973 to 1991 almost 5000 of the donors have developed some form of cancer. Frozen serum samples collected from a few months to 18 years prior to clinical recognition of their disease are consequently available for research purposes. The aim of the JANUS-project is to search in these premorbid sera for chemical, biochemical, immunological or other changes that might be indicative of cancer development at early stages. Gas chromatography-mass spectrometry and two-dimensional protein electrophoresis have been used to evaluate the stability of the frozen sera. Some recent findings are: CA125 is elevated several months prior to diagnosis of ovarian cancer; serum thyroglobulin may be a preclinical tumour marker in subgroups of thyroid cancer; low level of selenium in serum reflects increased risk of thyroid cancer; and raised antibodies in serum against Epstein-Barr virus is a risk factor for development of Hodgkin's disease. On-going research includes trace elements and cancer, and studies on lipid-profiles, diet and cancer. The serum bank may in principle be used for other purposes, e.g. in environmental studies. Analysis of sequential sera may determine chemical substances in the sera that might reflect differences in exposure to environmental pollutants in the period 1973-1991.

Dry reagent technology. Kodak Ektachem 700 XR in clinical enzymology.

The comparability of results for enzyme activity concentrations estimated with the methods recommended by the Scandinavian Committee on Enzymes(SCE) or the subcommittee on Enzymes of the European Committee for Clinical Laboratory Standards(ECCLS), and with the Kodak Ektachem methods, are discussed. As the Ektachem system in principle uses the IFCC methods at 37 degrees C as a reference, the results compare reasonably well for the alanine amino-transferase(ALAT), aspartate aminotransferase(ASAT), creatine kinase(CK) and gamma-glutamyltransferase(GT). The Ektachem reference method for lactate dehydrogenase(LD) is in principle the SCE method. The reasons for lower values with the SCE method are discussed. The interference on the Ektachem alkaline phosphatase (ALP) method from high concentrations of methotrexate(MTX) in serum, is shown. Results from our investigations on the interference by heparin in enzyme determinations on Ektachem are given. The problems with CK determinations in cancer patients regarding myocardial diseases are well known. When CK-BB is present in serum, the CK-B concentration is apparently lower using the Ektachem CK method than with use of the CK-MB slide, probably relating to the fact that chelator is omitted from the CK slide, while EGTA is supplied in the CK-MB slide. The user's dependence on the manufacturer for the choice of methods and the quality of the reagents, makes it important for laboratories and the Kodak Company to collaborate with the intention to continuously improve the Ektachem methodologies. The future possibilities of this technology seem to be nearly unlimited.

Evaluation of monocyte counting with two automated instruments by the use of CD 14-specific immunomagnetic Dynabeads.

Accurate determination of monocytes can be a problem with automated haematological analysers as well as with visual microscopy. We have compared monocyte counts from our two routine automated instruments, Technicon H*1 and Sysmex NE-1500. In the NE-1500 the monocyte counts appear to increase with increasing concentrations of neutrophils, compared with the H*1 results. The accuracy of the monocyte counts was assessed using Dynabeads M-450 CD14. These uniform magnetizable polystyrene beads coated with monoclonal antibody specific for CD14 membrane antigen isolated monocytes from the blood samples. The influence of this depletion on the monocyte counts and histograms from the two instruments and by visual microscopy were compared. On average 90% of the monocytes counted by visual microscopy were removed from six blood samples. In the same samples the beads removed an average of 75% of cells identified as monocytes by the H*1 but only 49% of those identified as monocytes by the NE-1500. These Dynabeads can be a useful tool in evaluating monocyte identification in different haematological situations and for manufacturers developing technology for automated leucocyte differential counting.

Haemoglobinometry on automated haematology analysers.

It is generally recognized that the standardized cyanmethaemoglobin (HiCN) method is the preferred method for the determination of haemoglobin in blood. In automated analysers, however, the reaction time available before the photometric measurement is too short. With the Ortho ELT800 we found that the conversion into HiCN took longer than 25 s. More important was the variation of results with the haemoglobin derivatives present in the blood sample. Our experiments suggest that Coulter counters and other automated analysers as well use denaturated globin haemichrome as the end product in their haemoglobin procedure although they profess to use HiCN by the addition of cyanide to the reagents. However, haemichrome is a suitable alternative for automated analysers as the conversion time is very short for all haemoglobin derivatives including HbCO. In the Coulter S Plus III where white cell size distribution analysis and haemoglobin determination are performed in the same solution, the haemoglobin derivative formed shortly after mixing is not a stable one. White cell size analysis and haemoglobin determination should preferably be performed in separate channels with different lysing reagents giving optimal conditions for each determination. Evaluation of the analysers would be easier if the manufacturers would give correct information on the chemistry of the haemoglobin method and state the composition of the reagents used.

Automated cyanide-free method for haemoglobin determination on Technicon H.1.

We have developed a cyanide-free haemoglobin method for our Technicon H.1 counter. By adding 2.5 mmol/l of the ionic surfactant sodium dodecyl sulphate in 154 mmol/l sodium chloride, the haemoglobins are converted to a stable product, denatured globin haemichrome, within the 25 s available on the instrument. The method is as precise and accurate as the original H.1 method, and the reagent is easily made in the laboratory at a very low price. Since the method is relatively safe with regard to waste disposal, the effluent from the counter can be drained into the laboratory sink. The method, a 'SDS-haemichrome method', has now worked very satisfactorily in routine use for a year. Manufacturers of haematological analysers should consider this haemoglobin method for their automated instruments.