The Clinical Utility of Circulating Epstein-Barr Virus DNA Concentrations in NK/T-Cell Lymphoma: A Meta-Analysis

Extranodal nasal-type NK/T lymphoma treated with chemotherapy and radiotherapy: case series from a European tertiary referral center and review of the literature

PURPOSE

Extranodal nasal-type NK/T-cell lymphoma (ENKTL) is very rare in western countries and few data are available regarding the prognosis and the outcome of patients treated for this disease. We aimed to evaluate the prognosis, the pattern and risk factors of disease failure after combined therapy and also performed a review of the literature.

PATIENTS AND METHODS

We retrospectively analyzed 20 patients with (ENKTL) who underwent L‑Asparaginase based chemotherapy followed by (chemo-) radiotherapy between 2010 and 2020 in our center. Data on clinical characteristics and irradiation were collected. Failure patterns were recorded as local (tumor site), regional (regional lymph nodes) or distant failure (metastasis and/or nonregional lymph nodes).

RESULTS

During a median follow-up period of 46 months, disease failure was observed in 8 patients (40%). The 3‑year progression-free survival (PFS) and overall survival (OS) rates were 62.5 and 83.0%, respectively. The failure patterns were local (n = 6, 30%), regional (n = 3, 15%) and distant (n = 4, 20%). Among patients with local failure, all failures occurred within the radiation fields (100%). Univariate analysis showed that bilateral regional lymph node involvement (p = 0.0002), initial circulating EBV viral load ≥ 3.5 log (p = 0.03) and no negativation of EBV PCR after induction CT (p = 0.0497) were independent predictors of PFS.

CONCLUSION

Patients with bilateral lymph node involvement and/or high EBV viral load have a significant recurrence rate despite multimodal therapy. These results need to be confirmed by larger studies. Given the high rate of local recurrence within radiotherapy fields, the value of dose escalation should be considered. Patients at risk of relapse should be included in dedicated trials.

Virological Markers in Epstein–Barr Virus-Associated Diseases

Epstein–Barr virus (EBV) is an oncogenic virus infecting more than 95% of the world’s population. After primary infection—responsible for infectious mononucleosis in young adults—the virus persists lifelong in the infected host, especially in memory B cells. Viral persistence is usually without clinical consequences, although it can lead to EBV-associated cancers such as lymphoma or carcinoma. Recent reports also suggest a link between EBV infection and multiple sclerosis. In the absence of vaccines, research efforts have focused on virological markers applicable in clinical practice for the management of patients with EBV-associated diseases. Nasopharyngeal carcinoma is an EBV-associated malignancy for which serological and molecular markers are widely used in clinical practice. Measuring blood EBV DNA load is additionally, useful for preventing lymphoproliferative disorders in transplant patients, with this marker also being explored in various other EBV-associated lymphomas. New technologies based on next-generation sequencing offer the opportunity to explore other biomarkers such as the EBV DNA methylome, strain diversity, or viral miRNA. Here, we review the clinical utility of different virological markers in EBV-associated diseases. Indeed, evaluating existing or new markers in EBV-associated malignancies or immune-mediated inflammatory diseases triggered by EBV infection continues to be a challenge.

Efficacy of a short sandwich protocol, methotrexate, gemcitabine, L-asparaginase and dexamethasone chemotherapy combined with radiotherapy, in localised newly diagnosed NK/T-cell lymphoma: A French retrospective study

Extranodal NK/T-cell lymphoma, nasal type is a rare and aggressive form of lymphoma, historically associated with poor prognosis. We report here the results of a retrospective multi-centre study evaluating the efficacy of MGAD (methotrexate, gemcitabine, L-asparaginase and dexamethasone) regimen (two cycles) combined with 'sandwich' radiotherapy in 35 patients with localised newly diagnosed extranodal NK/T-cell lymphoma. Thirty-two patients (91%) reached complete remission. With a long median follow-up of 59.6 months, progression-free and overall survival at 2 and 5 years were 71%, 80% and 53%, 73%, respectively. Around one third of the patients experienced relapse within a median time of 14.5 months. Side-effects were manageable with grades 3-4 cytopenias, mucositis and infection in 50%, 24% and 21% of the cases, respectively. Monitoring of asparaginase activity was performed in 13 patients and showed inactivation of the drug in seven (54%) patients. Our results indicate that a short therapy by sandwich MGAD chemoradiotherapy is a tolerable and effective treatment option in localised newly diagnosed extranodal NK/T-cell lymphoma patients.

A diagnostic scoring model of ENKTCL in the nose-Waldeyer's ring based on logistic regression: Differential diagnosis from DLBCL

Objective

To establish a logistic regression model based on CT and MRI imaging features and Epstein-Barr (EB) virus nucleic acid to develop a diagnostic score model to differentiate extranodal NK/T nasal type (ENKTCL) from diffuse large B cell lymphoma (DLBCL).

Methods

This study population was obtained from two independent hospitals. A total of 89 patients with ENKTCL (n = 36) or DLBCL (n = 53) from January 2013 to May 2021 were analyzed retrospectively as the training cohort, and 61 patients (ENKTCL=27; DLBCL=34) from Jun 2021 to Dec 2022 were enrolled as the validation cohort. All patients underwent CT/MR enhanced examination and EB virus nucleic acid test within 2 weeks before surgery. Clinical features, imaging features and EB virus nucleic acid results were analyzed. Univariate analyses and multivariate logistic regression analyses were performed to identify independent predictors of ENKTCL and establish a predictive model. Independent predictors were weighted with scores based on regression coefficients. A receiver operating characteristic (ROC) curve was created to determine the diagnostic ability of the predictive model and score model.

Results

We searched for significant clinical characteristics, imaging characteristics and EB virus nucleic acid and constructed the scoring system via multivariate logistic regression and converted regression coefficients to weighted scores. The independent predictors for ENKTCL diagnosis in multivariate logistic regression analysis, including site of disease (nose), edge of lesion (blurred), T2WI (high signal), gyrus like changes, EB virus nucleic acid (positive), and the weighted score of regression coefficient was 2, 3, 4, 3, 4 points. The ROC curves, AUCs and calibration tests were carried out to evaluate the scoring models in both the training cohort and the validation cohort. The AUC of the scoring model in the training cohort were 0.925 (95% CI, 0.906-0.990) and the cutoff point was 5 points. In the validation cohort, the AUC was 0.959 (95% CI, 0.915-1.000) and the cutoff value was 6 points. Four score ranges were as follows: 0-6 points for very low probability of ENKTCL, 7-9 points for low probability; 10-11 points for middle probability; 12-16 points for very high probability.

Conclusion

The diagnostic score model of ENKTCL based on Logistic regression model which combined with imaging features and EB virus nucleic acid. The scoring system was convenient, practical and could significantly improve the diagnostic accuracy of ENKTCL and the differential diagnosis of ENKTCL from DLBCL.

Comprehensive Analysis and Summary of the Value of Immunophenotypes of Mature NK Cell Tumors for Differential Diagnosis, Treatment, and Prognosis

Background

Few studies have been performed to comprehensively analyze and summarize the immunophenotype and differential diagnosis of mature NK cell tumors, and there is often overlap between tumorigenic and reactive NK cell phenotypes. Furthermore, the impact of different phenotypes on patient prognosis has rarely been reported.

Methods

The degree of expression of extracellular and intracellular markers of NK cells in each group was compared by FCM, and the differences in expression of various markers among different disease groups and their impact on prognosis have been analyzed and summarized.

Results

Compared with normal NK cells, tumor cells of ANKL and ENKTL had characteristics of being more activated and progressive with larger FSC, in contrast to NK-CLPD and RNKL. Differential diagnoses with RNKL, ANKL, and ENKTL have broader FCM clues. In contrast, the phenotypes of NK-CLPD and RNKL are not significantly different, and consistent phenotypic abnormalities require ongoing monitoring to confirm malignant clones. The sensitivity of differentiating malignant NK cells from reactive NK cells by KIRs alone was poor. The clustering results showed that CD5, CD16, CD56, CD57, CD94, CD45RA, CD45RO, HLA-DR, KIRs, Granzyme B, Perforin and Ki-67 were differentially distributed in the expression of three NK cell tumors and reactive NK cell hyperplasia, so a comprehensive judgment using a wide range of antibody combinations is required in disease staging diagnosis. The tumor cell loads in BM and PB were also compared, and there was a clear correlation between the two. Moreover, the sensitivity of PB for monitoring tumor cells was up to 87.10%, suggesting that PB could be used as an alternative to BM for the diagnosis and screening of NK cell tumors. Analysis of the phenotypic impact of ENKTL patients on prognosis showed that those with CD7 and CD45RO expression had a poor prognosis, while those with positive KIRs had a better prognosis.

Conclusion

This study systematically characterized the FCM of mature NK cell tumors, emphasizing the importance and clinical value of accurate immunophenotyping in diagnosing, classifying, determining prognosis, and guiding treatment of the disease.

DDGP vs. SMILE in Relapsed/Refractory Extranodal Natural Killer/T-cell Lymphoma, Nasal Type: A Retrospective Study of 54 Patients

Extranodal natural killer/T-cell lymphoma, nasal type (ENKL) is a rare peripheral T-cell lymphoma that predominantly occurs in Asian and South American populations. The treatment of ENKL has been a challenge for a long time. This study was conducted to compare the clinical efficacy and safety of cisplatin, dexamethasone, gemcitabine, and pegaspargase (DDGP) and methotrexate, dexamethasone, ifosfamide, L-asparaginase, and etoposide (SMILE) regimens for relapsed/refractory ENKL and explore the prognostic factors. From October 2014 to July 2019, 54 patients with relapsed/refractory ENKL who received DDGP or SMILE chemotherapy were retrospectively assessed in this study. Thirty-one patients received DDGP chemotherapy and 23 patients received SMILE chemotherapy. A higher complete response rate was observed in patients treated with DDGP regimen (61.3% vs. 30.4%, P = 0.025). The DDGP group (95% confidence interval (CI) of 5-year progression-free survival (PFS): 24.6-66.2%; 95% CI of 5-year overall survival (OS): 8.5-91.7%) was also significantly associated with longer 5-year PFS and 5-year OS (P = 0.008 for 5-year PFS, P = 0.023 for 5-year OS). More serious leucopenia (P = 0.021), neutropenia (P = 0.041), and allergy (P = 0.040) were observed in the SMILE group. Post-treatment Epstein-Barr virus (EBV)-DNA status (P = 0.001 for PFS, P = 0.018 for OS) was identified as a significant prognostic factor for PFS and OS in multivariate analysis. The present research suggested that compared with SMILE chemotherapy, DDGP chemotherapy can significantly improve the response and survival of relapsed/refractory ENKL with better tolerance. Post-treatment EBV-DNA status was identified as a significant prognostic factor for PFS and OS in relapsed/refractory ENKL.