Efficacy and Safety of the Modified EPOCH Regimen (Etoposide, Vincristine, Doxorubicin, Carboplatin, and Prednisolone) for Adult T-cell Leukemia/Lymphoma: A Multicenter Retrospective Study

BACKGROUND

We retrospectively analyzed patients with untreated aggressive adult T-cell leukemia/lymphoma who received the modified EPOCH (mEPOCH) regimen.

PATIENTS AND METHODS

Patients received up to 6 mEPOCH cycles. Etoposide (50 mg/m²/day), doxorubicin (10 mg/m²/day), and vincristine (0.4 mg/m²/day) were each given as a continuous 96-hour infusion on days 1 to 4. Prednisolone (40 mg/m²/day) was given intravenously or orally on days 1 to 4 and then tapered and stopped on day 7, and carboplatin (dose calculated for each patient individually using Calvert's formula according to a target under the curve of 3 mg/mL/min) was given as a 2-hour intravenous infusion on day 6.

RESULTS

In 103 patients, overall response rate and complete response rate were 58% and 25%, respectively. With a median follow-up of 8.9 months, the median survival time was 9.8 months (95% confidence interval, 7.2-13.9 months). The median progression-free survival (PFS) was 4.2 months (95% confidence interval, 3.4-5.7 months). Patients who completed ≥ 4 cycles experienced significantly better overall survival and PFS compared with those who completed < 4 cycles. Twenty-eight patients underwent allogeneic hematopoietic stem cell transplantation after mEPOCH and demonstrated significantly prolonged overall survival and PFS compared with those who did not undergo transplantation.

CONCLUSION

The mEPOCH regimen is effective with tolerable adverse effects and may be an alternative treatment option for adult T-cell leukemia/lymphoma.

Indigenous tropical spastic paraparesis in Madrid (Spain). Experience on screening of human T-lymphotropic virus

We have recently documented a case of tropical spastic paraparesis by HTLV-I in a Spanish patient. HTLV-I infection is rare in Europe, and hardly ever is accompanied by symptoms, but if it does it could trigger a major health issue. This case is presented here, as well as a discussion on the situations in which HTLV-I detection is justified. An analysis was made of the HTLV diagnostic requests at our centre during 2014-2015 (n=123). The diagnostic algorithm was: 1) Enzyme immunoassay, 2) Reverse hybridization, and 3) Proviral DNA detection by PCR. The results showed several situations of HTLV screening, emphasising those related to paraparesis (22%). Seven cases of HTLV-I infection were found: five in patients from endemic regions, one in an HIV-infected patient, and the case of TSP mentioned above. HTLV-I surveillance in non-endemic regions is a challenging issue, as the cost-benefit ratio is not well-established. This case report emphasises the importance of including HTLV within the differential diagnosis of insidious spastic paraparesis.

The thioredoxin antioxidant system

The thioredoxin (Trx) system, which is composed of NADPH, thioredoxin reductase (TrxR), and thioredoxin, is a key antioxidant system in defense against oxidative stress through its disulfide reductase activity regulating protein dithiol/disulfide balance. The Trx system provides the electrons to thiol-dependent peroxidases (peroxiredoxins) to remove reactive oxygen and nitrogen species with a fast reaction rate. Trx antioxidant functions are also shown by involvement in DNA and protein repair by reducing ribonucleotide reductase, methionine sulfoxide reductases, and regulating the activity of many redox-sensitive transcription factors. Moreover, Trx systems play critical roles in the immune response, virus infection, and cell death via interaction with thioredoxin-interacting protein. In mammalian cells, the cytosolic and mitochondrial Trx systems, in which TrxRs are high molecular weight selenoenzymes, together with the glutathione-glutaredoxin (Grx) system (NADPH, glutathione reductase, GSH, and Grx) control the cellular redox environment. Recently mammalian thioredoxin and glutathione systems have been found to be able to provide the electrons crossly and to serve as a backup system for each other. In contrast, bacteria TrxRs are low molecular weight enzymes with a structure and reaction mechanism distinct from mammalian TrxR. Many bacterial species possess specific thiol-dependent antioxidant systems, and the significance of the Trx system in the defense against oxidative stress is different. Particularly, the absence of a GSH-Grx system in some pathogenic bacteria such as Helicobacter pylori, Mycobacterium tuberculosis, and Staphylococcus aureus makes the bacterial Trx system essential for survival under oxidative stress. This provides an opportunity to kill these bacteria by targeting the TrxR-Trx system.