Chlorambucil-induced chromosome damage to human lymphocytes is dose-dependent and cumulative

Chlorambucil combination therapy in refractory serpiginous choroiditis: A cure?

Purpose

To find a remedy for serpiginous choroiditis refractory to oral prednisone and chlorambucil treatment.

Observations

Eight eyes of four patients (all female) with advanced macular involvement secondary to serpiginous choroiditis were included in the study. The average age of the patients was 45.2 years. One eye of each patient was legally blind and the lesion was close to the fovea in the other eye. All four patients failed oral prednisone and chlorambucil therapy. However, case 1 responded to chlorambucil treatment after intravitreal dexamethasone implant implantation and discontinuation of oral prednisone. Case 2 responded to chlorambucil therapy when oral prednisone was stopped in combination with infliximab therapy. Due to long follow-up period of more than four years, these two cases are considered to be cured. Case 3 and case 4 were not able to achieve remission with chlorambucil and immunomodulatory therapy. They refused intravitreal steroid implant due to side effects profile.

Conclusions and importance

The stability of WBC counts within toxic levels close to normal or lower limits of normal (3000–4500 cells/μl) during treatment with chlorambucil is an essential factor for the success of this therapy. A combination of dexamethasone intravitreal implant with chlorambucil therapy can be an effective and promising regimen in inducing and maintaining remission in refractory serpiginous choroiditis patients who fail a combination of systemic corticosteroid and chlorambucil therapy.

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Serpiginous choroiditis may be recurrent or refractory to chlorambucil in conjunction with systemic corticosteroids.

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The stability of WBC counts within lower limits of normal is an essential factor for the success of chlorambucil therapy.

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This can be achieved with dexamethasone intravitreal implant or systemic immunomodulatory without systemic corticosteroid therapy.

Pharmacologic Treatment of Noninfectious Uveitis

Uveitis encompasses a spectrum of diseases whose common feature is intraocular inflammation, which may be infectious or noninfectious in etiology (Nussenblatt and Whitcup 2010). Infectious causes of uveitis are typically treated with appropriate antimicrobial therapy and will not be discussed in this chapter. Noninfectious uveitides are thought have an autoimmune component to their etiology and are thus treated with anti-inflammatory agents.

Methotrexate in ocular manifestations of Behcet's disease: a longitudinal study up to 15 years

BACKGROUND

Ocular manifestations of Behcet's disease (BD) need aggressive treatment to prevent severe loss of vision or blindness. Cytotoxic drugs are the main therapeutic agents and the first line treatment. Methotrexate is the least toxic, used mainly for posterior uveitis. We present here the outcome of eye lesions with methotrexate and prednisolone, in a longitudinal study of up to 15 years, on 682 patients (5447 eye-years of follow-up).

PATIENTS AND METHODS

Methotrexate was started at 7.5-15 mg/week. Prednisolone was added at 0.5 mg/kg/daily, then adjusted as needed.

INCLUSION CRITERIA

(i) fulfilling the International Criteria for Behcet's Disease; and (ii) having active posterior uveitis (PU). Visual acuity (VA) was calculated on a scale of 10. Activity indexes were calculated for PU and retinal vasculitis (RV) for each eye. Total Inflammatory Activity Index (TIAI) demonstrating the inflammatory index of both eyes of the patient, and Total Adjusted Disease Activity Index (TADAI) showing both TIAI + VA were also calculated.

RESULTS

Overall results: the mean VA improvement was 0.4 (P < 001), PU 1.2 (P < 0.001) and RV 0.6 (P < 0.001). VA improved in 46.5%, PU in 75.4%, and RV in 53.7% of eyes. TIAI improved in 74% of patients and TADAI in 69.4%. VA was aggravated in 37.2%, PU in 11.1%, and RV in 30.3% of eyes. TIAI was aggravated in 17.4% and TADAI in 21.6% of the patients. The remaining kept their baseline values.

CONCLUSION

All parameters improved, PU better than RV. Improvement of VA was the least, mainly due to secondary cataracts.

Moesin is a biomarker for the assessment of genotoxic carcinogens in mouse lymphoma

1,2-Dibromoethane and glycidol are well known genotoxic carcinogens, which have been widely used in industry. To identify a specific biomarker for these carcinogens in cells, the cellular proteome of L5178Y mouse lymphoma cells treated with these compounds was analyzed by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF mass spectrometry (MS). Of 50 protein spots showing a greater than 1.5-fold increase or decrease in intensity compared to control cells on a 2-D gel, we focused on the candidate biomarker moesin. Western analysis using monoclonal rabbit anti-moesin confirmed the identity of the protein and its increased level of expression upon exposure to the carcinogenic compounds. Moesin expression also increased in cells treated with six additional genotoxic carcinogens, verifying that moesin could serve as a biomarker to monitor phenotypic change upon exposure to genotoxic carcinogens in L5178Y mouse lymphoma cells.

Comparative tolerability of treatments for juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) includes several forms of chronic arthritis in children. Treatments are chosen according to the type and severity of the disease. Nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids remain the mainstays of therapy. Traditional slower acting anti-rheumatic drugs, such as gold therapy, penicillamine, sulfasalazine, tiopronin and hydroxychloroquine, are usually poorly active in children. In addition, adverse effects are common, including severe macrophage activation syndrome with gold therapy or sulfasalazine. Low dose, once weekly methotrexate has emerged as the therapeutic agent of choice for children who fail to respond adequately to the administration of an NSAID, especially in those with the extended oligoarticular subtype of the disease. Other immunosuppressive agents, such as cyclosporin, are sometimes combined with methotrexate. In recent years, novel treatments have been developed. Autologous hematopoietic stem cell transplantation is effective in a number of children with severe JIA, whose disease has been refractory to conventional therapy. However, only short term follow-up data are currently available for this novel therapy. In addition, severe infections complicated by macrophage activation syndrome and death have been reported. Finally, anti-tumour necrosis factor-alpha therapy has shown efficacy in more than two-thirds of children with JIA and polyarthritis, and other cytokine inhibitors may be soon available.

Micronucleus frequency in the oral mucosa and lymphocytes of patients with Behcet's disease

Behçet's disease (BD) is a chronic, multisystemic, inflammatory disorder characterized mainly by recurrent oral and genital aphthous ulcerations and uveitis. Our study aimed to determine the genetic damage in patients with BD. The micronucleus (MN) frequency was counted in peripheral lymphocytes and exfoliated cells of the patients with BD. MN analysis was performed in peripheral lymphocytes of 30 patients with BD and in 20 healthy controls by the cytokinesis-block method, and on uncultured cells of the oral cavity in 10 patients and 9 healthy controls. We found significantly higher MN rates in lymphocytes of the patients than the control subjects (P = 0.000). There were no significant differences between the patients with or without treatment (P = 0.860). The MN frequency in exfoliated cells of the patients was higher than in those of healthy controls (P = 0.013), and there was no significant difference between the exfoliated cells of the treated and untreated patients (P = 0.201). Our results indicate that genetic damage may play a secondary but important part in the aetiology of BD and that treatment with colchicine does not induce MN.

Long-term follow-up of patients treated with short-term high-dose chlorambucil for sight-threatening ocular inflammation

PURPOSE

To determine the effectiveness of short-term high-dose chlorambucil in the treatment of sight-threatening uveitis and to ascertain the incidence of severe side effects, particularly late malignancy.

DESIGN

Retrospective, noncomparative interventional case series.

PARTICIPANTS

Fifty-three patients treated at the University of Illinois at Chicago Eye and Ear Infirmary and the private office of one of the authors for severe sight-threatening uveitis.

METHODS

Treatment with short-term high-dose chlorambucil (2-9 months of therapy).

MAIN OUTCOME MEASURE

Visual acuity and degree of inflammation were assessed at every visit. The development of systemic side effects, including malignancy, was assessed using a detailed questionnaire.

RESULTS

Total cumulative dose of chlorambucil ranged from 392 to 5200 mg with an average of 1429 mg. The maximum daily dose ranged from 10 to 30 mg with an average of 20 mg. Average duration of treatment was 16 weeks with a range of 7 to 40 weeks. Seventy-seven percent of patients treated were in remission with an average follow-up of 4 years (range: 6 months to 24 years). Forty-seven percent had at least two lines of improvement in Snellen visual acuity after treatment, with an average gain of 3.5 lines. Adverse effects include secondary amenorrhea, nonophthalmic herpes zoster, testicular atrophy, and erectile dysfunction. None of the patients had developed a malignancy as of their last follow-up.

CONCLUSION

Short-term high-dose chlorambucil therapy may be a reasonable option in patients with intractable sight-threatening uveitis.

Efficacy and safety of chlorambucil in intractable noninfectious uveitis: the Massachusetts Eye and Ear Infirmary experience

PURPOSE

To report our experience with the use of chlorambucil for otherwise treatment-resistant uveitis and to assess its safety and efficacy.

DESIGN

Noncomparative interventional case series.

PARTICIPANTS

Twenty-eight patients with intractable noninfectious uveitis.

METHODS

We reviewed the records of 28 patients (56 eyes) with chronic noninfectious uveitis who were treated with chlorambucil from 1987 to 2000. Diagnoses included Adamantiades-Behçet's disease (ABD) (7 patients), juvenile rheumatoid arthritis (JRA)-associated uveitis (10 patients), pars planitis (2 patients), sympathetic ophthalmia (1 patient), idiopathic uveitis (6 patients), Crohn's disease (1 patient), and HLA-B27-associated uveitis (1 patient). All patients were refractory to other immunomodulatory therapy and systemic steroids. The median duration of treatment with chlorambucil was 12 months (range, 4-50 months), whereas the median daily dosage was 8 mg (range, 4-22 mg). Patients were followed for a median follow-up period of 46 months (range, 4-166 months) after chlorambucil treatment was begun and continued to be followed for relapse after cessation of therapy.

MAIN OUTCOME MEASURES

Visual outcome, response to treatment, treatment-related side effects, drug dosage, previous and final treatment, discontinuation of systemic corticosteroids.

RESULTS

Chlorambucil was discontinued in seven patients because of side effects: two females had temporary amenorrhea develop, two patients had unacceptable gastrointestinal intolerance, one patient had infection, and 2 patients had progressive leukopenia. Nineteen patients (68%) showed positive clinical response to the treatment, four (14%) initially responded then relapsed after discontinuation of the drug, three patients with ABD had improvement of ocular disease but worsening of systemic symptoms, and two had persistent inflammation. Visual acuity was improved in 24 eyes (43%), stable in 22 (39%), and worsened in 10 eyes (18%). Systemic prednisone was successfully discontinued in 19 of the 28 patients (68%), and 14 patients were free of inflammation at the end of follow-up without any systemic medication.

CONCLUSIONS

Chlorambucil can be a safe and effective alternative for preserving vision in patients with otherwise treatment resistant uveitis.

Developments in the treatment of uveitis

Uveitis remains a challenging field to the ophthalmologist as the disease causes significant morbidity and the use of traditional forms of treatment is restricted by limited effectiveness and considerable side effects. This article explores new agents used in the treatment of uveitis as well as the potential of agents used successfully in experimental uveitis. This paper also reviews agents in use for a long time but now used in novel ways.

Karyotypic analysis of 32 malignant epithelial ovarian tumors

The identification of recurrent specific cytogenetic findings in various malignancies has provided an improved means to diagnose and treat patients. To date, no characteristic markers have been found for epithelial ovarian cancer. This is due, in part, to several contributory factors, including the inability to identify optimal growth conditions for culture and the fact that most analyses of advanced-stage tumors are obtained from malignant effusions rather than from solid tissue. In addition, many reports include previously treated patients. In this study, 32 untreated solid epithelial ovarian tumors, including 8 tumors of low malignant potential (LMP), were obtained from primary and metastatic sites at initial surgical staging. Using a 2-culture plastic technique for tissue growth, we achieved a 96% short-term culture success rate. Only 4 normal 46,XX karyotypes were identified. Diploid or near-diploid genomes were associated with few cytogenetic alterations. Complex karyotypic morphologies were consistently associated with advanced or poorly differentiated tumors. Nonrandom cytogenetic aberrations most commonly involved chromosomes 1 and 6. A novel translocation, t(1;6)(p10;p10), was identified in both a metastatic LMP tumor and a poorly differentiated invasive tumor. This cytogenetic rearrangement can potentially be regarded as a clinically relevant early marker for tumorogenesis. Finally, karyotypes from both primary and metastatic sites were subject to a comparative analysis in 11 patients. In 4 cases, greater chromosomal complexity was associated with the primary site.

Monitoring of occupational exposure to cytostatic anticancer agents

Many anticancer agents have been shown to be carcinogenic, mutagenic and teratogenic in experimental animals and in in vitro test systems. Epidemiological data on the association of second neoplasms with a specific chemotherapy treatment is available on some 30 agents, and in the case of 10 compounds the overall evidence on human carcinogenicity has been evaluated to be conclusive (Group 1: IARC, 1987 and 1990). The primary source of human exposure to anticancer drugs is from their use in therapy of cancer. However, persons employed in the manufacture, preparation and administration of the drugs to patients and in nursing patients may also be exposed. Safe handling of anticancer drugs, since the introduction of various general handling guidelines, is now good practice in hospitals, pharmacies and drug manufacturing companies of most developed countries. Careless handling of cancer chemotherapeutic agents may lead to exposure of the personnel in amounts detectable with chemical or biological methods in the body fluids or cell samples of the subjects. The exposure is typically to mixed compounds over long-term and to low exposure levels with accidental peaks. Therefore, the use of biological exposure markers is appropriate for the monitoring of such exposure patterns. The biological markers/methods for exposure assessment are either non-specific (e.g., cytogenetic damage, point mutations or 32P-post-labelling adducts in peripheral blood lymphocytes, urinary mutagenicity) or specific for a given compound (immunological methods for DNA adducts, specific analytical methods). Studies have revealed minor amounts of cyclophosphamide in the urine of pharmacy technicians and nurses handling the drug even when taking special safety precautions (Sessink et al. (1994a) J. Occup. Med., 36, 79; Sessink et al. (1994b) Arch. Env. Health, 49, 165). Another study showed surface wipe samples with measurable cyclophosphamide even away from the handling site (McDevitt et al. (1993) J. Occup. Med., 5, 57). These studies strongly implicate the importance of skin absorption as an exposure route. Also accidental spillage is never completely avoidable (Sorsa et al. (1988) Mutation Res., 204, 465-479). The potential confounders (smoking etc.), toxicokinetics of the agent(s) to be assessed and individual working practices should be carefully considered in any exposure assessment studies using human body fluid samples. Environmental monitoring on indicator cytostatics should be combined into studies designed to identify potential occupational exposure situations to anticancer agents. A properly performed study should also include dissemination of information to the workers to create a psychologically positive atmosphere for this important work.

Increased risk of leukaemia in patients with juvenile chronic arthritis treated with chlorambucil

Two cases of acute leukaemia have developed in a group of 77 patients treated with chlorambucil (Chl) because of severe juvenile chronic arthritis. The total follow-up from the beginning of Chl treatment in these patients was 560 years, indicating a highly increased risk of leukaemia. Despite favourable results, especially in patients with secondary amyloidosis, Chl should only be used in selected cases.

Epidemiological and etiological aspects of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are increasingly recognized as a cause of bone marrow failure, and are at least as frequent as acute myeloid leukemias. While the overall incidence is about 2-4/100,000/year, incidence figures rise steeply with age. Incidence rates of 20-30/100,000/year in persons over 70 demonstrate that MDS are among the most common hematological neoplasias in this age group. However, due to difficulties of diagnosis and classification, patient registration in population-based registers is far from complete. As a prerequisite for truly representative statistics, future revisions of disease classification systems must incorporate MDS as a separate group of disorders. The difficulties in conducting epidemiological studies also impede the identification of risk factors for the development of MDS. Current knowledge of occupational risk factors is also reviewed here. More rapid progress in our understanding of MDS may come from recent advances in methodology that have begun to shed some light on the cytogenetic and molecular aspects of leukemogenesis in general, and MDS in particular. Non-random chromosomal changes can be found in about 50% of cases at diagnosis, but they are probably late events in the evolution of MDS, reflecting the progressive genomic instability of the premalignant clone. Proto-oncogene mutations have also been suggested to be relevant to the pathogenesis of MDS, but longitudinal studies of point mutations of the N-ras proto-oncogene revealed that such events, although often associated with rapid deterioration and transformation to AML, also appear to be late events during the course of disease. Therefore, it remains a major challenge to identify those lesions that initiate the multistep development of preleukemia. As the incidence of MDS correlates strongly with age, it is reasonable to presume that age-dependent changes of the hematopoietic system may play a role in the initiation of MDS. Aging is probably associated with a compromised marrow reserve through reduction in the size of the stem cell pool. Through increased proliferative activity, the remaining stem cells may be particularly vulnerable to mutagenic insults. Immunological attack on stem cells, mitochondrial DNA mutations, and the regulatory influence of the hematopoietic microenvironment must also be considered as possibly contributing to the early stages of MDS.

Sister-chromatid exchange: second report of the Gene-Tox Program

This paper reviews the ability of a number of chemicals to induce sister-chromatid exchanges (SCEs). The SCE data for animal cells in vivo and in vitro, and human cells in vitro are presented in 6 tables according to their relative effectiveness. A seventh table summarizes what is known about the effects of specific chemicals on SCEs for humans exposed in vivo. The data support the concept that SCEs provide a useful indication of exposure, although the mechanism and biological significance of SCE formation still remain to be elucidated.

The treatment of minimal change nephrotic syndrome: lessons learned from multicentre co-operative studies

Minimal change nephrotic syndrome (MCNS) is the most frequent type of nephrotic syndrome in childhood. Treatment aims to induce remission, prevent relapses and avoid side-effects. MCNS is responsive to immunosuppressive therapy with glucocorticosteroids, alkylating drugs and cyclosporine A. From results of multicentre controlled studies it became evident that the initial treatment with prednisone should be intensive, i.e. for 12 weeks, in order to reduce the risk of subsequent relapses. Treatment of relapses should be standardized in order to categorize the patient's disease for further treatment. In case "frequent relapsers" develop signs of steroid-toxicity, they should be treated with alkylating drugs: frequent relapsers without steroid dependency with cyclophosphamide or chlorambucil for 8 weeks, steroid-dependent cases with cyclophosphamide for 12 weeks. If frequent relapses re-occur after cytotoxic drug therapy, treatment with cyclosporine A should be considered. Starting dose is 100-150 mg/m2 per day and needs to be adjusted to the whole blood trough level. Treatment with cyclosporine A must be strictly controlled in order to avoid chronic nephrotoxicity. Cyclosporine A does not cure MCNS. It is only effective as long as it is administered; therefore long-lasting treatment is necessary in most cases.

Sister chromatid exchange analysis in monitoring chlorambucil therapy in primary nephrotic syndrome of childhood

Sister chromatid exchange (SCE) analysis is the most sensitive method for assessing chromosome damage induced by chemical mutagens. We report the SCE of peripheral blood lymphocytes in children with primary nephrotic syndrome (NS) treated with chlorambucil. Group I consisted of 20 normal children, group 2 of 14 children with primary NS who had never received a cytotoxic drug and group III of 7 children with primary NS who had received chlorambucil, which was discontinued 6-36 months prior to the study. Group IV consisted of 4 nephrotic children who were receiving chlorambucil therapy during the study. There was no significant increase in SCE in group III compared with group I or group II (P much greater than 0.05). A significant rise in SCE (P less than 0.05) was seen in all patients in group IV.

Azathioprine, cyclophosphamide and chlorambucil

Immunosuppressive agents serve a major role in the management of once-fatal conditions such as the systemic necrotizing vasculitides, but they are also being used in more common, chronic inflammatory disorders such as rheumatoid arthritis. The drugs are all capable of reducing cell division but they differ in their modes of action. This is in keeping with their differing rates of action, and different indications. Azathioprine is a valuable alternative to slow-acting antirheumatic drugs in older patients with rheumatoid arthritis. Cyclophosphamide has transformed the outlook of many forms of vasculitis. Chlorambucil is particularly useful in improving the prognosis for children with amyloidosis secondary to juvenile chronic arthritis. We have tried to highlight the role of these drugs in a number of rheumatic diseases. We have emphasized their clinical applications, with some laboratory evidence for their effects. The major side-effects are reviewed. Finally, we have discussed their possible mechanisms of action.

Baseline and phosphoramide mustard-induced sister-chromatid exchanges in cancer patients treated with cyclophosphamide

Determinations of baseline sister-chromatid exchanges (SCE) have been used extensively as indicators of previous mutagen exposure in both animals and humans. Hypersensitivity to mutagen-induced SCE levels has also been studied in a variation on the basic technique as an indication of previous mutagen exposure in a stressed or provocative test system. The genotoxicity of the alkylating anti-cancer drugs including cyclophosphamide (CP) has been examined previously by determining baseline SCEs in peripheral blood lymphocytes from treated cancer patients. This study examined the in-vivo genotoxic effects of CP therapy by comparing baseline and phosphoramide mustard (PM)-induced SCEs in therapeutically (in-vivo) treated cancer patients with SCE levels in newly diagnosed, but not treated patients. Therapeutically treated patients showed statistically higher baseline SCE frequencies than untreated control patients with a mean SCE/cell of 6.95 vs. 5.25, p less than 0.016. When net SCE values (induced minus baseline) were determined in PM-exposed cells in-vitro both at low dose (0.1 microgram/ml PM) and high dose (0.25 microgram/ml PM) however, the difference was not significant between therapeutically treated and untreated control patients. The return to control SCE levels as a function of time since last therapeutic treatment was also evaluated and no difference was found between the rate of decline of PM-induced SCEs and baseline SCE levels over time.

Herpes simplex virus and the rheumatic diseases

A viral aetiology for rheumatoid arthritis and inflammatory connective tissue diseases has been sought in general terms first, by studying viral growth patterns in lymphocytes from the blood and lesions of patients affected second, by analysing lymphocyte concentrations of the interferon-induced enzyme 2-5 oligo-adenylate synthetase (2-5 A); and third, by probing Southern blots of lymphocyte DNA with viral probes. Indirect evidence consistent with a viral aetiology has been found in several such diseases, but direct proof has been difficult to adduce. There is some suggestion that herpes simplex viral (HSV) DNA is present in Behcet's blood lymphocytes, but the findings are inconsistent. It is also plausible that viruses such as HSV do not induce these diseases through classic immunopathological mechanisms, but as "promoters" of abnormal lymphoproliferation in individuals with predisposing defects, possibly related to selective DNA repair defects.

Cytogenetic effects of dacarbazine on mouse bone marrow cells in vivo

The mutagenicity of dacarbazine was assayed in an in vivo test utilizing mouse bone marrow cells. The dose rates used in the experiments were computed according to the standard surface area of the mouse and were proportional to the human dose rate. These were 0.27, 0.44 and 0.60 mg/30 g body weight, each given twice daily at an interval of not less than 6 h. The duration of drug treatment was 24, 48 and 72 h. This alkylating agent proved to be mitodepressive and produced a 3-fold reduction in the mitotic index. The drug also induced chromosome anomalies mainly in the form of chromatid gaps and breaks. These anomalies were proportional to dose rate and duration of drug treatment.

Twenty cases of sympathetic ophthalmia

We reviewed the charts of 20 patients with sympathetic ophthalmia who were seen in the uveitis clinic at the Eye and Ear Infirmary within an 11-year period. Of these 20 patients 14 maintained 20/50 or better visual acuity in at least one eye. We found early enucleation to be associated with a better visual prognosis, possibly due to earlier diagnosis and faster, more aggressive therapy rather than a reduction in antigenic load. The clinical appearance of Dalen-Fuchs nodules appears to indicate a more severe stage of disease. Chlorambucil was useful in patients with severe disease. To be effective and to lessen its side effects chlorambucil was given in daily dosages that were increased weekly over a short period to achieve bone marrow suppression. After a course of chlorambucil therapy intraocular inflammation could be controlled with topical steroids alone.

The effects of four drug regimens on sister chromatid exchange frequency in patients with lymphomas

Patients undergoing first-line chemotherapy after diagnosis of lymphoma have considerable DNA damage in their peripheral blood lymphocytes, using sister chromatid exchange (SCE) frequency as a sensitive indicator. Different drug regimens produce different patterns of changes in SCE frequency. These may be related to their potential to induce second malignancies.

Use of T cell cloning to detect in vivo mutations induced by cyclophosphamide

By cloning T cells, mutations at the hypoxanthine-guanine phosphoribosyltransferase locus were quantified in peripheral blood lymphocytes of 12 patients with connective tissue diseases receiving long-term cyclophosphamide. Frequency of mutation was higher than in control subjects and was related to the duration of therapy; therefore, some cells with mutations are long-lived, and these cells accumulate in the peripheral circulation. Mutation frequency was also independently related to age. The results indicate that even low doses of cyclophosphamide are mutagenic and may explain, in part, why these patients are at risk of drug-induced malignancy.

Evaluation of sister chromatid exchange as an indicator of sensitivity to N-ethyl-N-nitrosourea-induced carcinogenesis in rats

Sister chromatid exchange (SCE) frequencies in peripheral lymphocytes are a frequently used endpoint to indicate exposures to genotoxins in groups of humans. The aim of this study was to ascertain, in an experimental design, whether or not SCE rates have any association with the risk of cancer at the individual level in rats exposed to a known carcinogen. Individual SCE rates were determined in three consecutive analyses in cultured blood lymphocytes of 50 adult male Wistar rats. Analyses were done before as well as 24 hr and 7 days after a single intraperitoneal administration of 0, 25, 50, or 75 mg/kg of N-ethyl-N-nitrosourea (ENU). The animals were followed until death; also, the relationship between SCEs and carcinogenic outcome, i.e., the presence or absence of tumors, and their latency period were examined. ENU significantly decreased the life expectancy of the rats. The tumor types most clearly associated with ENU treatment were various gliomas and thyroid-gland and testicular tumors. ENU induced a moderate (maximally 1.6-fold) increase in the mean frequency of SCEs/cell at both sampling times after treatment. The effect was somewhat more pronounced 1 day rather than 1 week after treatment. The mean SCE rates in rats with ENU-specific cancers or in animals with early or multiple tumors did not differ from those in animals that survived no less than 65 weeks or longer without developing tumors. In ENU-treated animals with tumors, no relationship was found between the mean SCE rate and survival time. It is concluded that in outbred Wistar rats the SCE response in cultured lymphocytes does not indicate individual susceptibility to the carcinogenic action of ENU. On a group basis, however, animals with high SCE rates were shown to have increased risk of cancer.

A chromosome study of three ovarian tumors

The cytogenetic results of three different types of malignant ovarian tumors are reported. Their chromosomes were studied indirectly by using either peritoneal washings or ascitic fluids. Detected in the peritoneal washings from a treated case of serous cystadenocarcinoma with papillary involvement, stage III, was a clone of pseudodiploid cells. They were found after 12 months of chemotherapy. No supporting evidence of malignancy was found cytologically. Relatively simple karyotypes were obtained from metaphases found in the ascitic fluid of a patient surgically treated for an immature teratoma, stage II, grade 3. Consistent abnormalities found were trisomy 2, del(3)(p14), and der(5)t(5;8)(q33;q11). Of prime interest in a case of dysgerminoma, stage IV, was the finding of the isochromosome i(12p), a recognized nonrandom abnormality of malignant testicular tumors [1-5].

Sister-chromatid exchange frequencies in fibroblasts and lymphocytes of patients with systemic lupus erythematosus

Sister-chromatid exchange (SCE) frequencies have been measured in lymphocytes and fibroblasts of patients with systemic lupus erythematous (SLE) and healthy controls, and in lymphocytes of control patients with serum anti-nuclear antibodies (ANA) but no other disease manifestations of SLE. The SCEs of SLE lymphocytes were higher than those of the controls but the SCEs of the SLE fibroblasts did not differ from those of the controls. The SCEs of the controls with positive ANA did not differ significantly from those of the healthy controls. There was no correlation between SCE frequencies of the SLE lymphocytes and disease activity determined by many clinical and laboratory measurements. Primary and secondary DNA-repair defects in SLE cells are considered.

Sensitivity of lymphocytes from patients with systemic lupus erythematosus to the induction of sister chromatid exchanges by alkylating agents and bromodeoxyuridine

Several authors have suggested that the cells of patients with systemic lupus erythematosus (SLE) have defects of DNA repair. Cells from patients with the classical chromosomal instability syndromes, thought to be due to defects in DNA repair, are hypersensitive to the chromosome damaging effects of some DNA damaging agents, measured as sister chromatid exchange (SCE). We have observed that lymphocytes of patients with SLE are not more sensitive than lymphocytes from healthy individuals to the SCE inducing effects of the DNA damaging agents methyl nitrosourea, methyl methanesulphonate, chlorambucil, and bromodeoxyuridine. These observations do not support the suggestion that cells of patients with SLE have an underlying defect of DNA repair.

Sister-chromatid exchange frequencies in lymphocytes of controls and patients with connective tissue diseases

It has been considered by some workers that sister-chromatid exchange (SCE) frequencies are elevated in patients with scleroderma and systemic lupus erythematosus (SLE). However, these observations were based on limited numbers of patients. Other have postulated the presence of a defect in DNA repair in cells from patients with various connective tissue diseases, including scleroderma and SLE. We report our findings from a large survey of SCE frequencies in patients with connective tissue diseases. Their diagnoses are scleroderma, SLE, rheumatoid arthritis, juvenile chronic arthritis, Behcet's syndrome and polyarteritis nodosa. These patients had never received cytotoxic drugs. Healthy individuals, hospital patients with diagnoses other than connective tissue disease and relatives of patients with scleroderma have been used as controls. The results have been analysed by generalized linear modelling, and we have shown that patients with SLE and Behcet's syndrome and controls with viral infections have elevated SCE frequencies, both before and after adjustments have been made for the effect on SCEs of an individual's age, smoking habits, sex and race. The SCEs of patients with scleroderma and their relatives were normal. SCE frequencies increased with age by 4% per decade and the SCE frequencies of smokers were approximately 12% higher than those of nonsmokers of similar age. The sex of an individual did not significantly affect SCEs but individuals from the Middle East were found to have lower counts than those originating from other parts of the world.

Sister chromatid exchange frequencies in patients with scleroderma and their relatives

Sister chromatid exchange (SCE) analysis is a sensitive measure of chromosome damage induced by many agents which damage DNA. These agents have been reported to be present in the serum of patients with scleroderma. Chromosome aberrations are thought to be more common in cells of these patients and their relatives than in cells of controls. We have observed that the SCE frequencies in blood lymphocytes of patients with scleroderma and their relatives do not differ from those of controls.

Acute nonlymphocytic leukemia 5 years after treatment with cisplatin, vinblastine, and bleomycin for disseminated testicular cancer

The combination of cisplatin, vinblastine, and bleomycin (PVB) was used to treat a 25-year-old man for disseminated testicular germ cell cancer, leading to a complete remission. Acute nonlymphocytic leukemia (ANLL), resistant to chemotherapy, developed 5 years later. The secondary nature of this ANLL was corroborated by the detection of nonrandom chromosomal aberrations in bone marrow cells of chromosomes, 7, 5, and 3. This is one of the first reports of possible leukemogenic activity of PVB treatment when applied without additional irradiation or alkylating agents.

Variation of SCE frequency in lymphocyte cultures from patients with Hodgkin's disease before, during, and after treatment

Seven patients with newly-diagnosed Hodgkin's disease, having standard mustine-vinblastine-prednisolone-procarbazine therapy, had a large and regular pattern of rise in SCE frequency in their peripheral lymphocytes, which apparently started to fall before the end of the course (32 wk). In contrast, SCE frequency fell below normal in the lymphocytes of nine patients having mantle radiotherapy. Twenty-eight patients studied 2-13 yr after initial chemotherapy or radiotherapy for Hodgkin's disease had normal or near normal SCE frequencies.

Chemotherapy of advanced ovarian adenocarcinoma: a randomized comparison of combination versus sequential therapy using chlorambucil and cisplatin

Three hundred and sixty-nine patients with advanced ovarian adenocarcinoma were treated in a prospective randomized trial comparing combination versus sequential therapy with chlorambucil and cisplatin. Initial tumor response rates were similar but combination chemotherapy was associated with significantly prolonged time to first disease progression (median 28 weeks for chlorambucil and 42 weeks for combination chemotherapy). Second-line treatment with cisplatin in patients failing initial chlorambucil caused tumor response in 16.9%. Overall time to ultimate disease progression was similar between the treatment groups. The surgically documented complete response rate (second-look surgery at approximately equal to 12 months) and the survival was similar in the two treatment arms. Multivariate analysis of prognostic factors for survival in this trial showed that bulk of residual disease at time of starting therapy and the development of myelosuppression during therapy were the most important.

Chlorambucil therapy in rheumatoid arthritis: clinical experience in 28 patients and literature review

Our clinical experience in 28 patients receiving chlorambucil for rheumatoid arthritis (RA) and the reports on chlorambucil therapy are reviewed. Our study population and other reports generally represent patients with severe RA who had either failed to improve or developed significant toxicity during previous treatment with conventional slow acting anti-rheumatic drugs (SAARDs). Seventy-two percent of patients had a significant clinical improvement during chlorambucil therapy and reports of complete remission are given, although the incidence of remission is unknown. Hematologic complications are often reported, but appeared more frequently in our experience than previously reported. Hematologic toxicity required that chlorambucil be discontinued in the majority of our cases. Two deaths from suspected drug induced malignancies are reported. Although chlorambucil appears to be effective in the control of active RA, the potential for drug induced toxicity and malignancies may outweigh the benefit of continued use of this experimental therapy in RA.

Long-term effects of chemotherapy on lymphocyte chromosomes from patients treated for gestational trophoblastic tumours

A cytogenetic follow-up study of patients treated with chemotherapy for gestational trophoblastic tumours was undertaken. In some cases, high levels of chromosome damage were found to persist in lymphocytes for several years after completion of therapy. These results are compared with those found in similar studies of non-malignant and other malignant diseases. The relevance of these findings to the risk of subsequent chemotherapy-induced malignancy is discussed.

Chlorambucil induced chromosome damage in juvenile chronic arthritis

Sister chromatid exchanges, a sensitive measure of chromosome damage, were counted in peripheral blood lymphocytes from 23 patients with juvenile chronic arthritis receiving long term, low dose chlorambucil treatment. Thirty five patients with juvenile chronic arthritis who had not been treated with cytotoxic drugs served as controls. All of the treated patients have cells with abnormal sister chromatid exchange frequencies. Damage is related to the daily dose and may, in part, be determined by the duration of treatment. Sister chromatid exchanges from nine patients who had received chlorambucil at some time in the past remained high for at least five months after stopping the drug. Long term follow up will determine whether sister chromatid exchange analysis can help predict those most at risk of drug induced malignancies.

Occupational exposure to anticancer drug--potential and real hazards

Many anticancer agents have been shown to be mutagenic, teratogenic and carcinogenic in experimental systems and second malignancies are known to be associated with several specific therapeutic treatments. Anticancer agents thus represent a class of occupational carcinogens, the handling of which should involve no unnecessary exposure. The available methodologies to detect possible exposures from ambient air and from biological samples are discussed, and the published data on results are reviewed. Analytical methods are available for the detection of most frequently used anticancer drugs from all groups, i.e., alkylating agents, mitotic inhibitors, antimetabolites and antibiotics. The ambient samples taken from sites of admixture of cytostatics have often shown detectable, but low concentrations of anticancer agents. Urine samples from patients under chemotherapy as well as from personnel handling the drugs occupationally in hospitals have been analyzed both chemically and for excreted mutagenicity. Both cisplatin and cyclophosphamide have been detected in the urine of patients; furthermore, cyclophosphamide was observed in the urine of nurses who formulate and deliver this drug. Urinary mutagenicity assays have given both positive and negative results in various groups of nursing and pharmacy personnel. Cytogenetic methods have, likewise, been applied for monitoring purposes. Most of the available data concerns chromosome aberrations (CA) or sister-chromatid exchanges (SCE) induced in peripheral blood lymphocytes of patients under chemotherapy. A few studies on groups occupationally exposed to anticancer drugs have given positive results, but also negative reports have appeared for these same cytogenetic parameters. No studies are as yet available on the possible carcinogenic effects of occupational handling of anticancer drugs. Two recent case-referent studies among hospital personnel have pointed to slightly increased risks of disorders in pregnancy outcome; one of the studies has shown an excess of spontaneous abortions and other malformations in children of females with a history of work with anticancer agents.

Mechanisms of action and clinical applications of cytotoxic drugs in rheumatic disorders

Failure to suppress disease activity in certain rheumatic disorders such as systemic lupus, polyarteritis nodosa, or Wegener's granulomatosis may significantly heighten the probability of a fatal outcome. In other rheumatic disorders (for example, rheumatoid or psoriatic arthritis) the disease left unchecked may indeed be severely crippling but rarely is it fatal. Thus the decision on whether to add a cytotoxic drug often evolves into a benefit-to-risk analysis, a decision in which the patient must also be intimately involved. There are two few well-controlled studies of the use of cytotoxic agents to make dogmatic statements regarding their use in the treatment of rheumatic disorders. Nevertheless, a review of the literature, some of which has been cited above, does permit one to make some reasoned judgments in choosing a drug for a particular disease (Table 2).

Incidence of neoplasms in patients with rheumatoid arthritis exposed to different treatment regimens

Immunosuppressive drugs have been used during the last 30 years in treatment of patients with severe rheumatoid arthritis. The drugs commonly used are cyclophosphamide and chlorambucil (alkylating agents), azathioprine (purine analogue), and methotrexate (folic acid analogue). There is evidence that all four immunosuppressive drugs can reduce synovitis, but disease activity almost always recurs after therapy is stopped. Since adverse reactions are frequent, less than 50 percent of patients are able to continue a particular drug for more than one year. Since it takes three to 12 months to achieve maximal effects, those patients who are unable to continue the drug receive little benefit from it. Patients treated with alkylating agents have an increased risk of development of acute nonlymphocytic leukemia, and both alkylating agents and azathioprine are associated with the development of non-Hodgkin's lymphoma. Cyclophosphamide therapy increases the risk of carcinoma of the bladder. There have been several long-term studies of patients with rheumatoid arthritis treated with azathioprine and cyclophosphamide and the incidence of most of the common cancers is not increased. Data on the possible increased risk of malignancy in rheumatoid arthritis are still being collected, and until further information is available, the use of immunosuppressive drugs, particularly alkylating agents, in the treatment of rheumatoid arthritis should be reserved for patients with severe progressive disease or life-threatening complications.