Involvement of C677T MTHFR variant but not A1298C in methotrexate-induced toxicity in acute lymphoblastic leukemia

Involvement of the ABCB1 C3435T Variant but Not the MTHFR C677T or MTHFR A1298C Variant in High-Dose Methotrexate-Induced Toxicity in Pediatric Acute Lymphoblastic Leukemia Patients in China

Purpose

It remains unclear whether the MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genetic variants are associated with methotrexate (MTX) elimination delay and high-dose MTX (HD-MTX) toxicities in the treatment of pediatric acute lymphoblastic leukemia (ALL). The aim of our study was to analyze the potential predictive role of MTHFR C677T, MTHFR A1298C and ABCB1 C3435T in toxicities and the relationship between these variants and MTX elimination delay during HD-MTX therapy in pediatric ALL patients.

Patients and Methods

We conducted a retrospective study on ALL patients receiving HD-MTX treatment with available MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genotype and 44-h plasma MTX levels. Logistic regression analyses and chi-square tests were used to assess the relationship between the variants and HD-MTX toxicities and MTX elimination delay.

Results

Genotype frequencies were in Hardy-Weinberg equilibrium. MTX elimination delay did not significantly differ between MTHFR C677T and MTHFR A1298C or ABCB1 C3435T. Leukopenia (P=0.028), neutropenia (P=0.034) and oral mucositis (P=0.023) were 6.444-fold, 4.978-fold and 9.643-fold increased, respectively, in ABCB1 C3435T homozygous genotype (TT) patients compared to wild-type (CC) patients. No significant association was found between the toxicities investigated and MTHFR C677T or MTHFR A1298C.

Conclusion

This study showed that the ABCB1 C3435T homozygous allele genotype (TT) is associated with increased MTX-related toxicities (leukopenia, neutropenia and oral mucositis). These results may help to distinguish pediatric ALL patients with a relatively high risk of MTX-related toxicities before HD-MTX infusion and optimize MTX treatment.

The effect of the plasma methotrexate concentration during high-dose methotrexate therapy in childhood acute lymphoblastic leukemia

Two hundred and thirty-one acute lymphoblastic leukemia (ALL) children with 1376 high-dose methotrexate (HD-MTX) courses (3-5 g/m2) were enrolled to analyze the influence of the plasma MTX concentration (CMTX) in ALL. The 24-h target peak CMTX (C24h) was set at 33 μmol/l for low-risk (LR) and 65 μmol/l for intermediate/high-risk (IR/HR) groups. The median C24h was 42.0 μmol/l and 69.7 μmol/l for LR and IR/HR groups, respectively. MTX excretion delay was observed in 14.6% of courses, which was more frequent in IR/HR groups (56.9% vs. LR group 40.2%, p = .014) and T-ALL patients (82.6% vs. B-ALL 47.1%, p = .001). MTX-related toxicities were more common in courses with MTX excretion delay. However, survival between the patients who failed to reach the target C24h or not, with or without MTX excretion delay, was comparable. These findings suggest that, owing to the effectiveness of risk stratification chemotherapy, CMTX does not exert an independent influence on the prognosis of childhood ALL.

Severe Adverse Toxic Effects of Low-Dose Methotrexate Treatment on an Ectopic Pregnancy Patient With Methylenetetrahydrofolate Reductase Mutations: A Case Report

Background: Low-dose methylenetetrahydrofolate (LD-MTX) has been widely used for the treatment of the ectopic pregnancy (EP) for many decades, and related severe adverse toxic effects are rare. Current studies have shown that the polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene can decrease the MTX clearance, leading to the metabolite accumulation. However, there is a lack of literature report on an MTHFR gene polymorphism associated with adverse toxic effects resulting from the use of LD-MTX in an EP. Case Presentation: We report a rare case of a 38-year-old female who developed persistent fever, grade IV myelosuppression, skin lesions, mucositis, and liver injury after single dose of LDMTX to treat EP. The personalized genetic testing showed that MTHFR TT (677C>T) and MTHFR AA (1298A>C) were detected. Gradually, the symptoms improved after calcium leucovorin (CF) rescue, continuous renal replacement therapy (CRRT), promoting blood system regeneration, and multiple supportive treatments. Conclusion: This is the first report on the serious adverse toxic effects of LD-MTX on an EP patient with MTHFR mutations. We aim to alert obstetricians and gynecologists to this rare condition. The unexpected life-threatening toxicity with LD-MTX should be highly considered and recognized early. In particular, some easily overlooked gastrointestinal, skin, and mucosal symptoms occur earlier than severe myelosuppression. When toxic effects are suspected, detecting the polymorphisms of an MTHFR gene and monitoring MTX concentration in blood could assist us to formulate individualized and active treatments.

Methotrexate related cutaneous adverse drug reactions: a systematic literature review

OBJECTIVES

Recently, there is an increased number of reports being published on Methotrexate (MTX) related cutaneous manifestations. We aimed to identify and critically appraise descriptive studies describing the MTX related skin manifestations, treatment approach, and their outcomes.

METHODOLOGY

An extensive literature search was performed in the PubMed, Embase, and Scopus databases from inception to April 2021 without any restrictions along with the bibliographic search of included studies, grey literature search, and a snowball search was performed in Google and Google Scholar to identify the relevant literature. Descriptive studies reporting MTX related cutaneous manifestations were considered for the review. The study selection, data extraction, and quality assessment were conducted by two independent reviewers and any disagreements were settled by consensus with the third reviewer.

RESULTS

31 out of 8,365 descriptive studies including 38 patients (22 females and 16 males) aged between 12 and 78 years prescribed for the management of rheumatoid arthritis, ankylosing spondylitis, and psoriasis were included in this review. Toxic epidermal necrolysis (TEN), papular eruption, vasculitis, erosions of psoriasis, ulcerated psoriatic plaques, local reactions, keratinocyte dystrophy, erythema multiforme, drug rash with eosinophilia and systemic symptoms, Steven Johnson syndrome and photosensitive dermatitis were the majority of MTX induced cutaneous reactions. Immediate withdrawal of MTX, providing appropriate care with anti-inflammatory, topical steroids, and supplementation with folic acid were reported to be effective for the management of the MTX related cutaneous manifestations.

CONCLUSIONS

Clinicians and healthcare professionals should be aware of possible acute cutaneous drug reactions induced by MTX to avoid further consequences and fatal conditions. Immediate withdrawal of MTX and supportive care were reported as an efficacious therapeutic management of acute cutaneous drug reactions.

PROSPERO REGISTRATION NUMBER

CRD42020220038.