Multifocal leukoencephalopathy associated with 5-fluorouracil and levamisole adjuvant therapy for colon cancer. A report of two cases and review of the literature. The INTACC. Intergruppo Nazionale Terpia Adiuvante Colon Carcinoma

Adverse reactions with levamisole vary according to its indications and misuse: a systematic pharmacovigilance study

AIM

Levamisole was initially prescribed for the treatment of intestinal worms. Because of immunomodulatory properties, levamisole has been used in inflammatory pathologies and in cancers in association with 5-fluorouracil. Levamisole is misused as a cocaine adulterant. Post-marketing reports have implicated levamisole in the occurrence of adverse drug reactions (ADRs) and its use is now limited in Europe and North America. In contrast, all other parts of the World continue to use single-dose as an anthelmintic. The aim of this study was to identify ADRs reported after levamisole exposure in VigiBase, the WHO's pharmacovigilance database, and analyze their frequency compared to other drugs and according to levamisole type of use.

METHODS

All levamisole-related ADRs were extracted from VigiBase®. Disproportionality analyses were conducted to investigate psychiatric, hepatobiliary, renal, vascular, nervous, blood, skin, cardiac, musculoskeletal and general ADRs associated with levamisole and other drugs exposure. In secondary analyses, we compared the frequency of ADRs between levamisole and mebendazole and between levamisole type of use.

RESULTS

Among the 1763 levamisole-related ADRs identified, psychiatric disorders (Reporting Odds-Ratio with 95% confidence intervals: 1.4 [1.2-2.6]), hepatobiliary disorders (2.4 [1.9-4.3]), vasculitis (6.5 [4.1-10.6]), encephalopathy (22.5 [17.4-39.9]), neuropathy (4.3 [2.9-7.1]), hematological disorders, mild rashes and musculoskeletal disorders were more frequently reported with levamisole than with other drug. The majority of levamisole-related ADRs occurred when the drug was administrated for a non-anti-infectious indication.

CONCLUSION

The great majority of the levamisole-related ADRs concerned its immunomodulatory indication and multiple doses regimen. Our results suggest that single-dose treatments for anthelmintic action have a good safety profile.

A fatal case after an intravenous injection of levamisole

Levamisole is a drug originally prescribed as an antihelmintic. Because of the occurrence of severe cases of agranulocytosis and leukoencephalitis it was removed from the French market in 1998 for human use, while it remains available for veterinary use. Nowadays in France its only use in humans is regulated by authorization for temporary use for its immunomodulatory properties in the treatment of nephritic syndrome.A 52-year-old man was found dead at his farm. Injection points were observed on his arm and a syringe containing a dark orange-brown liquid was found near the body. At his home, the discovery of a letter highlighted suicidal intent. Analysis of the aforementioned liquid, peripheral blood and urine confirmed the unique presence of levamisole. The femoral blood concentration of levamisole was of 25 mg/L whereas the femoral blood concentrations reported in cases of fatalities after cocaine use do not exceed 0.0056 mg/L. In humans, levamisole can be detected in biological samples after cocaine use as this drug is also an adulterant and one of its metabolites (aminorex) seems to have amphetamine-like properties. In this case, the man consumed levamisole from time to time for its stimulant and strengthening effects.Cases of fatal poisoning using levamisole are very rare and poorly documented, which makes the interpretation of postmortem blood levamisole concentration difficult.

Posterior reversible encephalopathy syndrome: A rare neurotoxicity after capecitabine

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a condition characterized by seizures, headache, visual disturbances, paresis, nausea and altered mental status. Risk factors include hypertension, eclampsia/pre-eclampsia, infection/sepsis, transplantation (allograft, bone marrow and solid organ) and immunosuppression, especially in association with autoimmune disorders and use of cyclosporine or chemotherapy.

CASE REPORT

A few days after starting the first cycle of treatment with capecitabine, a 50-year-old female with metastatic breast cancer experienced serious adverse events consisting of severe hematological, gastrointestinal and neurological toxicity. A brain magnetic resonance imaging, performed because of the severe state of confusion of the patient, confirmed PRES.

MANAGEMENT AND OUTCOME

The patient was admitted to the hospital; capecitabine was stopped and treatment was started with antibiotics, growth factor therapy and blood and platelet transfusions. Her clinical conditions slowly improved and the PRES resolved. A dihydropyrimidine dehydrogenase deficiency was identified.

DISCUSSION

The patient had previously been treated with another fluoropyrimidine, 5-fluorouracil, but without toxicity. A literature search was performed, and only six cases of PRES associated with capecitabine were found. Our case suggests that capecitabine differs from 5-fluorouracil in its mechanism of action and that at least one of the metabolites of capecitabine has the ability to cross the blood-brain barrier, causing neurotoxicity. We believe that it is useful to test for dihydropyrimidine dehydrogenase deficiency before using fluoropyrimidines and would encourage the reporting of such cases of PRES to gain a better overall picture of its incidence in this setting.

NARANJO SCORE

7.

Central Nervous System Vasculitis Due to Substance Abuse

Illicit drug abuse is a common differential diagnosis of acquired central nervous system vasculitis even though there are only a handful of histopathologically confirmed patients in the literature from among the many potential classes of abused drugs traditionally implicated in this disease. This article considers the major classes of illicit drugs in those with and without human immunodeficiency virus type-1 infection and acquired immune deficiency syndrome.

Redox biology in normal cells and cancer: restoring function of the redox/Fyn/c-Cbl pathway in cancer cells offers new approaches to cancer treatment

This review discusses a unique discovery path starting with novel findings on redox regulation of precursor cell and signaling pathway function and identification of a new mechanism by which relatively small changes in redox status can control entire signaling networks that regulate self-renewal, differentiation, and survival. The pathway central to this work, the redox/Fyn/c-Cbl (RFC) pathway, converts small increases in oxidative status to pan-activation of the c-Cbl ubiquitin ligase, which controls multiple receptors and other proteins of central importance in precursor cell and cancer cell function. Integration of work on the RFC pathway with attempts to understand how treatment with systemic chemotherapy causes neurological problems led to the discovery that glioblastomas (GBMs) and basal-like breast cancers (BLBCs) inhibit c-Cbl function through altered utilization of the cytoskeletal regulators Cool-1/βpix and Cdc42, respectively. Inhibition of these proteins to restore normal c-Cbl function suppresses cancer cell division, increases sensitivity to chemotherapy, disrupts tumor-initiating cell (TIC) activity in GBMs and BLBCs, controls multiple critical TIC regulators, and also allows targeting of non-TICs. Moreover, these manipulations do not increase chemosensitivity or suppress division of nontransformed cells. Restoration of normal c-Cbl function also allows more effective harnessing of estrogen receptor-α (ERα)-independent activities of tamoxifen to activate the RFC pathway and target ERα-negative cancer cells. Our work thus provides a discovery strategy that reveals mechanisms and therapeutic targets that cannot be deduced by standard genetics analyses, which fail to reveal the metabolic information, isoform shifts, protein activation, protein complexes, and protein degradation critical to our discoveries.

Novel levamisole derivative induces extrinsic pathway of apoptosis in cancer cells and inhibits tumor progression in mice

Background

Levamisole, an imidazo(2,1-b)thiazole derivative, has been reported to be a potential antitumor agent. In the present study, we have investigated the mechanism of action of one of the recently identified analogues, 4a (2-benzyl-6-(4′-fluorophenyl)-5-thiocyanato-imidazo[2,1-b][1], [3], [4]thiadiazole).

Materials and Methods

ROS production and expression of various apoptotic proteins were measured following 4a treatment in leukemia cell lines. Tumor animal models were used to evaluate the effect of 4a in comparison with Levamisole on progression of breast adenocarcinoma and survival. Immunohistochemistry and western blotting studies were performed to understand the mechanism of 4a action both ex vivo and in vivo.

Results

We have determined the IC₅₀ value of 4a in many leukemic and breast cancer cell lines and found CEM cells most sensitive (IC₅₀ 5 µM). Results showed that 4a treatment leads to the accumulation of ROS. Western blot analysis showed upregulation of pro-apoptotic proteins t-BID and BAX, upon treatment with 4a. Besides, dose-dependent activation of p53 along with FAS, FAS-L, and cleavage of CASPASE-8 suggest that it induces death receptor mediated apoptotic pathway in CEM cells. More importantly, we observed a reduction in tumor growth and significant increase in survival upon oral administration of 4a (20 mg/kg, six doses) in mice. In comparison, 4a was found to be more potent than its parental analogue Levamisole based on both ex vivo and in vivo studies. Further, immunohistochemistry and western blotting studies indicate that 4a treatment led to abrogation of tumor cell proliferation and activation of apoptosis by the extrinsic pathway even in animal models.

Conclusion

Thus, our results suggest that 4a could be used as a potent chemotherapeutic agent.

[Late-onset leukoencephalopathy induced by long-term chemotherapy with capecitabine and cyclophosphamide for liver metastasis from breast cancer]

A 55-year-old woman with a 3-year and 4-month history of liver metastasis from breast cancer underwent chemotherapy with capecitabine and cyclophosphamide for following 10-months. She did not have hypertension and was not pregnant. She showed dysarthria and mild somnolence, and her conscious level developed to semicoma after 6 days. She had pyrexia. Cerebrospinal fluid (CSF) demonstrated increased cell-count and elevated protein but no evidence of positive cytological finding and cultivation of bacteria was found in the CSF. Brain magnetic resonance imaging (MRI) revealed multiple lesions with hyperintensity in the brain stem, bilateral middle cerebellar peduncles, left splenium of corpus callosum, bilateral basal ganglia, bilateral thalami, bilateral corona radiata, and bilateral subcortical white matters of parietal lobes on the T(2) weighted and fluid attenuated inversion recovery (FLAIR) images. These lesions demonstrated mild hyperintensity on the diffusion weighted images but did not demonstrate hypointensity on the T(1) weighted images. Capecitabine and cyclophosphamide were discontinued at 4th day after onset of symptoms, and her conscious disturbance showed improvement slowly since day 12 after cessation of these drugs and hyperintensity areas detected on FLAIR image of MRI showed decreasing intensity after three weeks of onset. Capecitabine is an oral prodrug converted to 5-fluorouracil (5-FU). 5-FU and cyclophosphamide are known to induce leukoencephalopathy. Reversible multiple lesions with leukoencephalopathy on brain MRI which is called as a posterior reversible encephalopathy syndrome (PRES). Capecitabine is also reported to induce PRES in rare cases. Combination of these drugs was considered for the possible cause to induce leukoencephalopathy like PRES. Usually leukoencephalopathy occurs in relatively early time after start of chemotherapy with capecitabine or cyclophosphamide, but we consider that late-onset leukoencephalopathy can be induced by long-term chemotherapy with these drugs. It is necessary to observe leukoencephalopathy by brain MRI regularly when these drugs are used.

Chemotherapy associated central nervous system damage

Chemotherapy is commonly associated with harmful effects to multiple organ systems, including the central nervous system (CNS). Neurotoxicity may manifest as both acute and delayed complications, which is particularly a concern for long-term survivors. Patients may experience a wide range of neurotoxic syndromes, ranging from neuro-vascular complications and focal neurological deficits to generalized neurological decline with cognitive impairment, cortical atrophy and white matter abnormalities. Along with the use of more aggressive and combined treatment modalities and prolonged survival of cancer patients, neurological complications have been observed with increasing frequency. The mechanisms by which cancer therapy, including chemotherapy and radiation, result in neurological complications, have been poorly understood. Recent studies have now started to unravel the cell-biological basis for commonly seen neurotoxic syndromes and have provided compelling explanations for delayed neurological complications, such as cognitive decline, progressive myelin disruption and brain atrophy.

Encephalopathy secondary to capecitabine chemotherapy: a case report and discussion

Introduction. Capecitabine is an oral prodrug of 5-fluorouracil (5-FU) chemotherapy and is licenced for the treatment of breast and gastrointestinal cancers. Multifocal inflammatory leukoencephalopathy has been associated with intravenous 5-FU, but only a few cases of capecitabine-induced encephalopathy have been reported.

Setting. We describe here a case of encephalopathy following administration of Epirubicin/ Cisplatin/Capecitabine chemotherapy, review those cases previously described and suggest recommendations for management.

Results. Symptoms of neurotoxicity from 5-FU and capecitabine usually include confusion, ataxia, nystagmus, dysarthria, sensory loss, and memory loss. Withdrawal of the drug generally leads to improvement of symptoms and steroids are of only questionable benefit.

Conclusion. Patients on fluouropyrimidine drugs with new neurological symptoms should be investigated with brain MRI scan and the drug should be withdrawn until symptoms resolve. Dihydropyrimidine dehydrogenase deficiency should be excluded and ideally an alternative chemotherapy regime sought. We would encourage reporting of such incidences to gain a clearer picture of the incidence and optimal management. J Oncol Pharm Practice (2009) 15: 237—239.

Systemic 5-fluorouracil treatment causes a syndrome of delayed myelin destruction in the central nervous system

BACKGROUND

Cancer treatment with a variety of chemotherapeutic agents often is associated with delayed adverse neurological consequences. Despite their clinical importance, almost nothing is known about the basis for such effects. It is not even known whether the occurrence of delayed adverse effects requires exposure to multiple chemotherapeutic agents, the presence of both chemotherapeutic agents and the body's own response to cancer, prolonged damage to the blood-brain barrier, inflammation or other such changes. Nor are there any animal models that could enable the study of this important problem.

RESULTS

We found that clinically relevant concentrations of 5-fluorouracil (5-FU; a widely used chemotherapeutic agent) were toxic for both central nervous system (CNS) progenitor cells and non-dividing oligodendrocytes in vitro and in vivo. Short-term systemic administration of 5-FU caused both acute CNS damage and a syndrome of progressively worsening delayed damage to myelinated tracts of the CNS associated with altered transcriptional regulation in oligodendrocytes and extensive myelin pathology. Functional analysis also provided the first demonstration of delayed effects of chemotherapy on the latency of impulse conduction in the auditory system, offering the possibility of non-invasive analysis of myelin damage associated with cancer treatment.

CONCLUSIONS

Our studies demonstrate that systemic treatment with a single chemotherapeutic agent, 5-FU, is sufficient to cause a syndrome of delayed CNS damage and provide the first animal model of delayed damage to white-matter tracts of individuals treated with systemic chemotherapy. Unlike that caused by local irradiation, the degeneration caused by 5-FU treatment did not correlate with either chronic inflammation or extensive vascular damage and appears to represent a new class of delayed degenerative damage in the CNS.

Levamisole-induced multifocal inflammatory leukoencephalopathy: clinical characteristics, outcome, and impact of treatment in 31 patients

Levamisole (LEV) has been used as an immunomodulating medication in patients with recurrent aphthous ulcers and as an adjuvant for chemotherapy. LEV, with or without 5-fluorouracil (5-FU), induces multifocal inflammatory leukoencephalopathy (MIL). We identified 31 patients with LEV-induced MIL: 7 from our institution and 24 from a MEDLINE search. Twenty-one patients (67.7%) had been treated with a combination of LEV and 5-FU, while 10 patients had been treated with LEV alone. The onset of MIL was delayed in patients who took LEV and 5-FU in combination compared with the patients treated with LEV alone (11.7 +/- 3.7 vs. 4 +/- 2.5 wk, p < 0.001). Colon cancer (67.7%) was the most common indication for LEV administration. Gait ataxia occurred in 20 (64.5%) patients, and dysphagia was noted in 16 (51.6%) patients. Imaging studies revealed periventricular enhancement in 17 (54.8%) patients and supratentorial lesions in 16 (51.6%) patients. Cerebrospinal fluid studies showed lymphocytic pleocytosis in 10 of 21 (47.6%) patients. Early diagnosis of MIL and discontinuation of LEV is essential, yielding good recovery in most cases. Treatment with corticosteroids and/or intravenous immunoglobulin may be needed for this serious inflammatory encephalopathy. Twenty-nine patients exhibited improved clinical status and imaging findings after initial steroid or immunoglobulin treatment. Plasmapheresis may be an alternative regimen for patients with steroid resistance.

Analysis of tumor control and toxicity in patients who have survived at least one year after radiosurgery for brain metastases

PURPOSE

To better evaluate tumor control and toxicity from radiosurgery for brain metastases, we analyzed these outcomes in patients who had survived at least 1 year after radiosurgery.

METHODS AND MATERIALS

We evaluated the results of gamma knife stereotactic radiosurgery (SRS) for 208 brain metastases in 137 patients who were followed for a median of 18 months (range 12-122) after radiosurgery. The median patient age was 53 years (range 3-83). Ninety-nine patients had solitary metastases. Thirty-eight had multiple tumors. Sixty-nine patients underwent initial SRS with whole brain radiotherapy (WBRT), 39 had initial SRS alone, and 27 patients had failed prior WBRT. The median treatment volume was 1.9 cm(3) (range 0.05-21.2). The median marginal tumor dose was 16 Gy (range 12-25). The most common histologic types included non-small-cell lung cancer, breast cancer, melanoma, and renal cell carcinoma, which comprised 37.0%, 22.6%, 13.0%, and 9.13% of the lesions, respectively. Forty-five tumors were associated with extensive edema.

RESULTS

At 1 and 5 years, the local tumor control rate was 89.6% +/- 2.1% and 62.8% +/- 6.9%, distal intracranial relapse occurred in 23% +/- 3.6% and 67.1% +/- 8.7%, and postradiosurgical sequelae developed in 2.8% +/- 1.2% and 11.4% +/- 3.5% of patients, respectively. Multivariate analysis found that local control decreased with tumor volume (p = 0.0002), SRS without WBRT (p = 0.008), and extensive edema (p = 0.024); distal intracranial recurrence correlated with younger patient age (p = 0.0018); and postradiosurgical sequelae increased with increasing tumor volume (p = 0.0085).

CONCLUSION

Long-term control of brain metastases and complication rates in this selective series of patients surviving >or=1 year after radiosurgery were similar to previously reported actuarial estimates. Large metastases and metastases associated with extensive edema can be difficult to control by radiosurgery, particularly without WBRT.

Adjuvant chemotherapy in the treatment of colon cancer: randomized multicenter trial of the Italian National Intergroup of Adjuvant Chemotherapy in Colon Cancer (INTACC)

BACKGROUND

To determine whether the addition of leucovorin to the combination 5-fluorouracil plus levamisole prolongs disease-free survival and overall survival in patients with radically resected colon cancer (Dukes' B(2-3) and C).

PATIENTS AND METHODS

Patients (1703) were accrued between March 1992 and February 1995 in a large-scale clinical trial within five Italian cooperative groups. After stratification for center, patients were randomized as follows: arm A, 5-fluorouracil [450 mg/m(2) intravenous (i.v.) bolus on days 1-5] and levamisole (150 mg orally for 3 days, every 14 days for 6 months) versus arm B, 6-S-leucovorin (100 mg/m(2) i.v. bolus on days 1-5) followed by 5-fluorouracil (370 mg/m(2) i.v. bolus on days 1-5), plus levamisole (as arm A), every 4 weeks for six cycles.

RESULTS

After a median follow-up of 6.4 years no significant difference was seen for either disease-free survival (58% versus 60%, not significant) or 5-year overall survival (68% versus 71%, not significant), respectively. Gastrointestinal toxicity (World Health Organization grade 3/4) was more frequent in arm B (8% versus 18%, not significant).

CONCLUSIONS

In this trial the schedules used showed no statistically significant differences in terms of disease-free survival or overall survival in the treatment of colorectal cancer.

Progressive multifocal leukoencephalopathy after fludarabine therapy for low-grade lymphoproliferative disease

Fludarabine is becoming the initial therapy for low-grade lymphoproliferative malignancies, such as CLL and follicular lymphoma. Fludarabine is highly immunosuppressive in addition to being myelosuppressive and has been associated with neurotoxicity. Progressive multifocal leukoencephalopathy (PML) is an infection with JC virus of the white matter of the central nervous system seen mostly in immunosuppressed patients. We describe two patients treated with fludarabine who developed PML. Immunolabeling was positive for JCV in both patients, but PCR was repeatedly negative in one of them. We suggest that fludarabine may increase the risk of PML in patients with lymphoproliferative diseases.

Immunomodulation therapy in colorectal carcinoma

There has been much progress in the understanding of the relationship between the immune system and colorectal cancer. This has led to the use of immunomodulatory therapy in the adjuvant and palliative treatment of the condition. Although attempts at the use of non-specific immunomodulation with agents such as levamisole, cimetidine, alpha interferon and Bacillus Calmette-Guerin (BCG) have not produced significant clinical benefits when tested in randomized trials in both the adjuvant setting and for metastatic disease, promising results are being obtained with more specific therapy. Edrecolomab [corrected], a murine monoclonal antibody targeting the 17-1A antigen on malignant colorectal cells has produced a reduction in relapse and mortality rates when used as adjuvant treatment following surgery for Dukes' C colon cancer. Active specific therapy with autologous tumour vaccine administered with BCG has produced similar benefits in Dukes' B cancer. Both 3H1 anti-idiotypic antibody against carcinoembryonic antigen and 105AD7 antibody to gp72 glycoprotein have demonstrated in-vitro and in-vivo immune activation against tumour. Non-randomized studies postulate prolongation of survival using these antibodies in advanced disease. These agents are all currently being tested in randomized studies powered to detect meaningful survival differences and clinical benefit. Immune therapy offers the potential of low toxicity therapy in colorectal cancer and may have a role as an adjunct to conventional chemotherapy.

Neurological complications of 5-fluorouracil chemotherapy: case report and review of the literature

Neurological complications of 5-fluorouracil (5-FU) chemotherapy are uncommon events. The two patients presented demonstrate two manifestations of 5-FU neurotoxicity, namely a cerebellar syndrome in association with global motor weakness and bulbar palsy, and a bilateral third cranial (oculomotor) nerve palsy. Both highlight the rapid onset and severity of these unusual side effects but also emphasize that, unlike paraneoplastic syndromes or central nervous system involvement by tumour, complete spontaneous recovery is a potential outcome.