Clinical differences between nasal and extranasal natural killer/T-cell lymphoma: a study of 136 cases from the International Peripheral T-Cell Lymphoma Project. Blood. 2009;113:3931-3937. [PMID: 19029440 DOI: 10.1182/blood-2008-10-185256]

Can the radiation dose be safely reduced in the treatment of nk/T cell lymphoma?

The aim of this study is to investigate the feasibility and safety of dose reduction in the radiotherapy of NK/T-cell lymphoma. A retrospective collection of clinical and treatment data was conducted on 41 patients. The analysis aimed to assess whether the reduction in radiation therapy dosage affected patients' local control and survival. Among the 41 patients, all achieved complete remission after the initial treatment. With a median follow-up of 28.4 months, all except one patient demonstrated good control within the irradiated area. In the entire cohort, a total of 6 patients died and none of the deaths were caused by local tumor failure. The 3-year overall survival rate and progression-free survival rate was 83.8%, 94.4%, respectively. The incidence of long-term toxicity was low. It seems safe to reduce the prophylactic radiation dose to 45 Gy and the preliminary treatment results are satisfactory, with further reduction in side effects.

Update on T-Cell Lymphoma Epidemiology

PURPOSE OF REVIEW

T-cell lymphomas (TCLs) are a group of rare subtypes of non-Hodgkin lymphoma derived from mature T-lymphocytes. Recent updates in lymphoma classification based on the cell-of-origin pathogenesis have shed new light on TCL epidemiology and outcomes. Contemporary regional consortia and international studies, including those conducted recently in Asia and South America, have provided an updated delineation of the major subtypes across various global regions.

RECENT FINDINGS

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), remains the most common subtype globally except in Asia, where extra-nodal NK-T cell lymphoma (ENKTL) has emerged as the most prevalent. Angioimmunoblastic T-cell lymphoma (AITL) is the second most common subtype globally except in South America where its incidence falls behind adult T-cell leukemia/lymphoma (ATLL) and ENKTL. ALK-negative anaplastic large cell lymphoma (ALCL) has been recognized as the second most common subtype in some parts of South America. Studies on the newly classified breast implant-associated ALCL (BIA-ALCL) are beginning to reveal its distribution and risk factors. Deciphering the epidemiology of TCLs is a challenging endeavor due to the rarity of these entities and ongoing refinement in classification. Collaborative efforts on prospective registries based on the most current WHO classifications will help capture the true epidemiology of TCL subtypes to better focus resources for diagnostic, prognostic, and therapeutic efforts.

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.

Analysis of mutation profiles in extranodal NK/T-cell lymphoma: clinical and prognostic correlations

The molecular pathogenesis of extranodal NK/T-cell lymphoma (NKTCL) remains obscured despite the next-generation sequencing (NGS) studies explored on ever larger cohorts in the last decade. We addressed the highly variable mutation frequencies reported among previous studies with comprehensive amplicon coverage and enhanced sequencing depth to achieve higher genomic resolution for novel genetic discovery and comparative mutational profiling of the oncogenesis of NKTCL. Targeted exome sequencing was conducted to interrogate 415 cancer-related genes in a cohort of 36 patients with NKTCL, and a total of 548 single nucleotide variants (SNVs) and 600 Copy number variances (CNVs) were identified. Recurrent amplification of the MCL1 (67%) and PIM1 (56%) genes was detected in a dominant majority of patients in our cohort. Functional mapping of genetic aberrations revealed that an enrichment of mutations in the JAK-STAT signaling pathway, including the cytokine receptor LIFR (copy number loss) upstream of JAK3, STAT3 (activating SNVs), and downstream effectors of MYC, PIM1 and MCL1 (copy number gains). RNA in situ hybridization showed the significant consistence of MCL1 RNA level and copy number of MCL1 gene. We further correlated molecular and clinical parameters with overall survival (OS) of these patients. When correlations were analyzed by univariate followed by multivariate modelling, only copy number loss of LIFR gene and stage (III-IV) were independent prognostic factors of reduced OS. Our findings identified that novel loss of LIFR gene significantly correlated with the adverse clinical outcome of NKTCL patients and provided therapeutic opportunities for this disease through manipulating LIFR.

Extranodal natural killer/T cell lymphoma of the skeletal muscle

This case report highlights a case of extranodal NK/T cell lymphoma initially misdiagnosed as myositis, emphasizing the appearance on both MRI and FDG PET images. The patient presented with systemic symptoms and calf muscle swelling, prompting imaging studies that revealed diffuse muscle involvement. Despite negative myositis markers and inconclusive biopsy, post-amputation findings confirmed lymphoma with EBV positivity. The appearance in both MRI and FDG PET complicated the diagnostic process, underscoring the importance of considering lymphoma in cases of muscle-related symptoms to prevent delays in appropriate management. This case contributes to the understanding of the diagnostic challenges associated with extranodal NK/T cell lymphoma and emphasizes the significance of peripheral band-like features in imaging studies.

Analysis of the treatment and prognosis of 266 cases of extranodal natural killer/T-cell lymphoma, nasal type in a single medical center

Objective

To assess the impact of different treatment strategies and risk factors on the prognosis of patients with extranodal NK/T-cell lymphoma, nasal type (ENKTL) in a single medical center.

Methods and analysis

The clinical features of 266 patients with ENKTL were retrospectively analyzed, among whom those in stages I and II received sandwich therapy, while those in stages III and IV underwent chemotherapy plus autologous hematopoietic stem cell transplantation. The Kaplan-Meier curves, univariate and multivariate Cox regression analyses were employed for survival and prognosis analysis. Statistical significance was set at P<0.05.

Results

Following treatment, the post-intervention outcomes demonstrated a complete remission (CR) rate of 71.05% and a partial remission (PR) rate of 3.76%. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 70.4% and 70.9%, respectively. In addition, the PFS for patients in stage I/II was 79.8%, with an OS of 81.1%, whereas for those in stage III/IV, the PFS was 41.7% and the OS was 40.9%. Notably, the achievement of CR immediately after treatment was an independent prognostic factor (P<0.001). Patients in stage I/II depicted a favorable 5-year OS rate, while those in stage III/IV manifested a less favorable prognosis.

Conclusion

Stages of the disease and whether CR was achieved following treatment are important factors determining the survival and prognosis of patients with ENKTL. Further researches focusing on disease onset and mechanisms of drug resistance will contribute to better management of ENKTL.

Genomic features reveal potential benefit of adding anti-PD-1 immunotherapy to treat non-upper aerodigestive tract natural killer/T-cell lymphoma

Natural killer/T-cell lymphoma (NKTCL) is a highly heterogeneous disease with a poor prognosis. However, the genomic characteristics and proper treatment strategies for non-upper aerodigestive tract NKTCL (NUAT-NKTCL), a rare subtype of NKTCL, remain largely unexplored. In this study, 1589 patients newly diagnosed with NKTCL at 14 hospitals were assessed, 196 (12.3%) of whom had NUAT-NKTCL with adverse clinical characteristics and an inferior prognosis. By using whole-genome sequencing (WGS) and whole-exome sequencing (WES) data, we found strikingly different mutation profiles between upper aerodigestive tract (UAT)- and NUAT-NKTCL patients, with the latter group exhibiting significantly higher genomic instability. In the NUAT-NKTCL cohort, 128 patients received frontline P-GEMOX chemotherapy, 37 of whom also received anti-PD-1 immunotherapy. The application of anti-PD-1 significantly improved progression-free survival (3-year PFS rate 53.9% versus 17.0%, P = 0.009) and overall survival (3-year OS rate 63.7% versus 29.2%, P = 0.01) in the matched NUAT-NKTCL cohort. WES revealed frequent mutations involving immune regulation and genomic instability in immunochemotherapy responders. Our study showed distinct clinical characteristics and mutational profiles in NUAT-NKTCL compared with UAT patients and suggested adding anti-PD-1 immunotherapy in front-line treatment of NUAT-NKTCL. Further studies are needed to validate the efficacy and related biomarkers for immunochemotherapy proposed in this study.

Cutaneous Intravascular Hematolymphoid Entities: A Review

Intravascular lymphomas are rare disease conditions that exhibit neoplastic lymphoid cells that are confined mainly to the lumens of small capillaries and medium-sized vessels. The majority of the intravascular lymphomas are of B-cell origin, but they can include NK/T-cell and CD30+ immunophenotypes. In the histologic differential diagnosis are benign proliferations such as intralymphatic histiocytosis and intravascular atypical CD30+ T-cell proliferation. In this review, we discuss the clinical, histopathologic, and molecular findings of intravascular B-cell lymphoma, intravascular NK/T-cell lymphoma, intralymphatic histiocytosis, and benign atypical intravascular CD30+ T-cell proliferation.

A Rare Case of Gastric Extranodal NK/T-Cell Lymphoma With Orbital Involvement

Gastric extranodal NK/T-cell lymphoma (ENKTL) is a rare presentation of a rare disease. We report a 33-year-old woman presenting with epigastric pain, nausea, and vomiting. Endoscopic examination revealed gastric and duodenal ulceration. Biopsy of the ulcers revealed ENKTL. The patient began treatment, but developed hemorrhagic shock from her ulcers and died. Gastric ENKTL is a rare disease that presents with gastric ulceration. It has a high rate of mortality, and treatment is challenging because of its aggressive nature and lack of high-quality data to guide therapy.

Primary ophthalmic natural killer/T-cell lymphoma: A population-based study

BACKGROUND

Ophthalmic lymphomas, a subgroup of extra-nodal lymphomas, have seen an increase in incidence in recent decades. Of these, the NK/T-cell lymphoma (NKTL) subtype is particularly aggressive. Though prevalent mostly in Asian patients, data on ophthalmic NKTL is still limited, especially in the western population. This study aimed to provide an additional analysis of primary ophthalmic NKTL using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

A retrospective analysis was performed on the SEER database covering records from 2000 to 2020. Patients diagnosed with extranodal NKTL originating primarily from an ophthalmic structure were identified.

RESULTS

Out of 4540 ophthalmic lymphomas registered in the SEER database between 2000 and 2020, 9 cases (0.2%) corresponded to ophthalmic NKTL, occurring in patients with a median age of 67 years. The majority of these patients underwent chemotherapy (88.8%) and radiotherapy (66.6%). The 6-month overall survival (OS) and cancer-specific survival (CSS) were both at 50.8%, dropping significantly at the 2-year follow-up.

CONCLUSION

Primary orbital NKTL has a notably severe prognosis. An early diagnosis is important due to the aggressive nature of NKTL.

A Rare Case of Extranodal Natural Killer/T-cell Lymphoma, Nasal Type Associated With Hemophagocytic Lymphohistiocytosis in a Patient With Recurrent Sinusitis

We present a rare case of hemophagocytic lymphohistiocytosis (HLH) secondary to nasal-type extranodal natural killer/T-cell lymphoma (ENKL). Nasal-type ENKL is a rare subtype of non-Hodgkin's lymphoma usually associated with Epstein-Barr virus (EBV). The patient was a 19-year-old woman who presented with facial numbness, diminished hearing, and dysgeusia. She was febrile with palatal necrosis, loss of gag reflex, and cranial nerve palsies. Labs revealed neutropenia. Broad-spectrum antimicrobials, including amphotericin, were started. Given concern for invasive fungal disease, she underwent surgical debridement, which revealed inflamed fibrous tissue and extensive necrosis. Pathology showed no fungal elements or malignancy. Lack of clinical improvement and worsening palatal necrosis prompted additional debridement. Histology identified an atypical CD3+/CD56+ cellular infiltrate. Bone marrow biopsy showed prominent hemophagocytosis, but no malignancy. She met the criteria for HLH and high-dose dexamethasone was started. Her fevers resolved. Additional labs and nasal tissue sampling with EBV-encoded RNA staining were recommended. Flow cytometry was negative, but histology revealed ENKL nasal-type, with positive EBV-encoded RNA in situ hybridization. Plasma EBV DNA level was 11,518 IU/mL. The M-SMILE (dexamethasone, methotrexate, ifosfamide, l-asparaginase, and etoposide) regimen was initiated; one cycle led to marked improvement. EBV level returned to zero. Subsequent radiation and chemotherapy, followed by autologous stem cell transplant consolidation, led to complete remission. We conclude that ENKL may mimic invasive sinusitis clinically. Fibrinoid necrosis in vessels and surrounding tissues often leads to diagnostic delay. It is important to have a high degree of clinical suspicion for malignancy in cases of HLH and sinusitis unresponsive to appropriate therapy. Obtaining proper tissue, communication with the pathologist, and prompt initiation of therapy are crucial.

Initial diagnosis of extranodal NK/T-cell lymphoma in pericardial fluid with concomitant hemophagocytic lymphohistiocytosis (HLH)

Extranasal natural killer/T-cell lymphoma arising in the heart is rare and typically presents with non-specific clinical symptoms, necessitating a biopsy for a definitive diagnosis. We report an unusual case of a 48-year-old male who initially presented with chest pain and shortness of breath. Subsequent diagnosis via pericardial fluid analysis, including flow cytometry and immunohistochemical stains, revealed extranasal NK/T-cell lymphoma without sinonasal involvement. The analysis identified neoplastic lymphoid cells expressing CD2, cytoplasmic CD3, Epstein-Barr virus, and CD56 and exhibiting increased Ki-67 staining. Additionally, the patient developed hemophagocytosis lymphocytosis secondary to NK/T cell lymphoma. Treatment included an interleukin-1 receptor antagonist (anakinra), dexamethasone, rituximab, and etoposide. Unfortunately, the patient's condition rapidly deteriorated, leading to multiorgan failure and eventual demise. Given the rarity of this lymphoma, early diagnosis based on a high suspicion level provides the best chance for improved overall survival.

Clinical features, prognostic stratification, and treatment of advanced-stage non-nasal type extranodal natural killer/T-cell lymphoma: a multi-institutional real-world study

The present study aimed to investigate the clinical features, prognosis, and treatment of advanced-stage non-nasal type extranodal natural killer/T-cell lymphoma (ENKTCL). This real-world study retrospectively reviewed 56 newly diagnosed advanced-stage non-nasal type ENKTCL patients from two large-scale Chinese cancer centers in the last 10-15 years and screened 139 newly diagnosed advanced-stage nasal type ENKTCLs admitted during the same period for comparison. The non-nasal type ENKTCLs exhibited significantly higher Ki-67 expression levels compared to nasal type disease (P = 0.011). With a median follow-up duration of 75.03 months, the non-nasal group showed slightly inferior survival outcomes without statistically significant differences compared to the nasal group (median overall survival (OS): 14.57 vs. 21.53 months, 5-year OS: 28.0% vs. 38.5%, P = 0.120). Eastern Cooperative Oncology Group (ECOG) score ≥ 2 (hazard ratio (HR) = 2.18, P = 0.039) and lactic dehydrogenase (LDH) elevation (HR = 2.44, P = 0.012) were significantly correlated with worse OS in the non-nasal group. First-line gemcitabine-based chemotherapy regimens showed a trend toward slightly improved efficacy and survival outcomes compared to non-gemcitabine-based ones in the present cohort of non-nasal ENKTCLs (objective response rate: 91.7% vs. 63.6%, P = 0.144; complete response rate: 50.0% vs. 33.3%, P = 0.502; median progression-free survival: 10.43 vs. 3.40 months, P = 0.106; median OS: 25.13 vs. 9.30 months, P = 0.125), which requires further validation in larger sample size studies. Advanced-stage non-nasal type patients could achieve comparable prognosis with nasal cases after rational therapy. The modified nomogram-revised index (including age, ECOG score, and LDH) and modified international prognostic index (including age, ECOG score, LDH, and number of extranodal involvement) functioned effectively for prognostic stratification in non-nasal type ENKTCLs.

Serum aspartate aminotransferase, a novel potential biomarker of prognosis in extranodal natural killer/T cell lymphoma, nasal type

BACKGROUND

Aspartate aminotransferase (AST), an indicator of liver cell damage, was related to the prognosis of certain malignant tumors.

OBJECTIVE

This study examined the predictive value of AST in patients with extranodal natural killer/T cell lymphoma (ENKTL).

METHODS

We reviewed 183 cases diagnosed with ENKTL and selected 26 U/L as the optimum cut-off value of AST. We used the univariate and multivariate Cox regression to compare the different AST groups' overall survival (OS) and progression-free survival (PFS).

RESULTS

Prior to propensity score matching (PSM), Kaplan-Meier analysis showed that patients in the low AST subgroup had better OS and PFS than the high AST subgroup. Multivariate analysis revealed that AST was an independent indicator for prognosis. After PSM, the low AST subgroup maintained a significantly better OS and PFS than the high AST subgroup.

CONCLUSION

AST might represent a significant prognostic marker for ENKTL patients.

Extranodal natural killer/T-cell lymphoma coexisting with peripheral T-cell lymphoma, not otherwise specified

We report the case of a 52-year-old male who presented to our hospital with cervical lymphadenopathy. Lymph node biopsy revealed small atypical lymphoid cells positive for CD3 and CD5 and negative for CD56 and Epstein-Barr virus (EBV)-encoded small RNA (EBER) by in situ hybridization. CD4-positive cells and CD8-positive cells were mixed in almost equal numbers. He was diagnosed with peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). The patient received one cycle of chemotherapy, resulting in severe sepsis. While undergoing treatment in the intensive care unit with an antimicrobial agent and prednisone, ascitic fluid appeared. Abdominal aspiration revealed neutrophil-predominant ascites and microbiological studies revealed Candida albicans. However, ascites did not improve when treated with micafungin for Candida peritonitis. Abdominal aspiration was re-performed, and atypical lymphoid cells that were positive for CD3 and CD56 were detected. EBV-DNA levels in whole blood were significantly elevated. Atypical lymphoid cells were positive for EBER by in situ hybridization and Southern blot analysis showed EBV terminal repeat monoclonal patterns. Bone marrow examination revealed the same atypical lymphoid cells. Therefore, the patient was diagnosed with extranodal natural killer/T-cell lymphoma (ENKTL) with bone marrow involvement 3 months after the diagnosis of PTCL-NOS. Complications associated with PTCL-NOS and ENKTL are rare. PTCL-NOS, chemotherapy, sepsis, and prednisone might have led to immunodeficiency and reactivation of EBV, which might be one of the pathophysiologies for developing ENKTL. Our case indicates that measuring EBV-DNA in the blood is a simple and prompt examination to detect complications of EBV-associated lymphoma.

Nasal Maggot Infection in a Patient With Nasal Non-Hodgkin's Lymphoma

We describe a case of nasal non-Hodgkin's lymphoma in a 79-year-old Chinese patient accompany with nasal myiasis. The first 2 biopsies in this case were false negative. Subsequently, nasal maggots developed in this patient. After removing all maggots under nasal endoscopy, the patient continued to have recurrent fever and was transferred to a higher hospital for further treatment, in which he received a third biopsy. Unfortunately, several hours after the biopsy, the patient died for severe nasal bleeding. The final biopsy result indicated the neoplasm of the left nasal cavity was non-Hodgkin's lymphoma. This case illustrates the importance of repeated biopsies for nasal non-Hodgkin's lymphoma if necessary. Nasal myiasis is a secondary disease of nasal non-Hodgkin's lymphoma in this case.

Outcomes and prognostic factors of patients with Extranodal NK T cell lymphoma (ENKTL)

The staging, prognostication, and treatment of ENKTL has evolved over the years with better understanding of the disease biology. There is significant heterogeneity in the treatment followed across the world. Literature from India have been few with small number of patients. We studied the outcomes and prognostic factors of patients with ENKTL treated between May 2010 and December 2021 at our center. A total of 78 patients diagnosed with ENKTL were treated at our center. L-asparaginase based chemotherapy was administered in 84% of the patients. Close to 2/3rd patients received SMILE chemotherapy. After a median follow-up of 30 months (18.5-41.4 months), the median relapse free survival and overall survival for the overall population was 45 months (12-118 months) and 45 months (14-118 months) respectively. By multivariate analysis, PINK score of 2-4, non-receipt of RT and non-achievement of CR were associated with poor survival.

Comparative analysis of clinicopathologic characteristics and prognosis between nasal and nonnasal extranodal NK/T-cell lymphoma

BACKGROUND

The clinicopathologic characteristics and prognosis of nasal and nonnasal extranodal natural killer T-cell lymphoma (ENKTL) are considered to be different. However, the underlying features responsible for these differences are not well clarified especially in the era of asparaginase therapy.

METHODS

In total, 1007 newly diagnosed ENKTL patients from 11 medical centers were included in this study. Clinicopathologic characteristics and survival data were collected. The chi-squared test and Kruskal-Wallis test were utilized for the comparison of different groups. Univariable and multivariable Cox proportional hazards models were used to screen prognostic factors.

RESULTS

Overall, 869 (86.3%) patients were nasal forms. Compared to patients with nasal ENKTL, nonnasal patients were at more advanced stages and had poor performance status, bone marrow involvement, elevated serum lactate dehydrogenase (LDH), and CD56-negative status (p < 0.05). The 5-year overall survival (OS) for nasal and nonnasal patients were 65.6% and 45.0%, respectively. The OS of nasal forms patients were superior to nonnasal patients, especially in Eastern Cooperative Oncology Group performance status (ECOG PS) (≥2), advanced stage, KPI (HIR/HR), IPI (HIR/HR), PINK (HR), and high EBV DNA load groups. In patients treated with pegaspargase/L-asparaginase-based regimens, the OS of nasal patients was better than that of nonnasal patients. After adjusting the covariates of age, stage, ECOG PS score, LDH, B symptoms, and BM involvement, results showed that the nonnasal site was associated with poor survival of ENKTL.

CONCLUSIONS

The clinicopathologic characteristics and prognosis of nasal and nonnasal ENKTL patients are different. Nasal forms patients had superior OS than nonnasal patients, especially in the era of asparaginase.

Few and far between: clinical management of rare extranodal subtypes of mature T-cell and NK-cell lymphomas

While all peripheral T-cell lymphomas are uncommon, certain subtypes are truly rare, with less than a few hundred cases per year in the USA. There are often no dedicated clinical trials in these rare subtypes, and data are generally limited to case reports and retrospective case series. Therefore, clinical management is often based on this limited literature and extrapolation of data from the more common, nodal T-cell lymphomas in conjunction with personal experience. Nevertheless, thanks to tremendous pre-clinical efforts to understand these rare diseases, an increasing appreciation of the biological changes that underlie these entities is forming. In this review, we attempt to summarize the relevant literature regarding the initial management of certain rare subtypes, specifically subcutaneous panniculitis-like T-cell lymphoma, hepatosplenic T-cell lymphoma, intestinal T-cell lymphomas, and extranodal NK/T-cell lymphoma. While unequivocally established approaches in these diseases do not exist, we make cautious efforts to provide our approaches to clinical management when possible.

Disseminated Nasal subtype Extranodal NK/T-cell lymphoma and its diagnostic difficulties in antemortem biopsies

Extranodal NK/T- cell lymphoma (ENKTCL) is an aggressive lymphoma driven by Epstein-Barr virus (EBV) infection in genetically susceptible individuals. It was historically called a lethal midline granuloma. Due to the angio-destructive nature of ENKTCL, lymphoma cells are often accompanied and masked by necrosis and dense inflammation in the biopsy. Further, the biopsy may show vasculitis, which can mimic granulomatosis with polyangiitis. Due to these masquerades, ENKTCL is often misdiagnosed in the biopsy. Several biopsies may be required to establish the diagnosis. We describe the clinical course and autopsy findings of a young female who presented with a hard-palate ulcer. Antemortem biopsies failed to establish the diagnosis. The autopsy revealed an advanced nasal subtype of Extranodal NK/T-cell lymphoma with dissemination to the kidneys, adrenals, liver, spleen, and small intestine.

CD30 in Cutaneous Pathology

ABSTRACT

The discovery of CD30 as a diagnostic marker was essential in the identification of not only some lymphomas but also many other solid tumors and benign reactive conditions. Many CD30+ cutaneous disorders and tumors have been categorized since the identification of the marker. With the design of targeted therapies against CD30+ tumoral cells, the interest in CD30 determination was not only diagnostic but also mainly therapeutic. In this article, we explore the historical aspects of the discovery of CD30 and examine the main CD30-related cutaneous pathology, susceptible of anti-CD30 modern treatments.

Outcome and risk prediction of early progression in patients with extranodal natural killer/T cell lymphoma from the CLCG study

Recently, progression-free survival at 24 months (PFS24) was defined as clinically relevant for patients with extranodal NK/T cell lymphoma. Herein, the clinical data from two independent random cohorts (696 patients each in the primary and validation datasets) were used to develop and validate a risk index for PFS24 (PFS24-RI), and evaluate its ability to predict early progression. Patients achieving PFS24 had a 5-year overall survival (OS) of 95.8%, whereas OS was only 21.2% in those failing PFS24 (P<0.001). PFS24 was an important predictor of subsequent OS, independent of risk stratification. The proportion of patients achieving PFS24 and 5-year OS rates correlated linearly among risk-stratified groups. Based on multivariate analysis of the primary dataset, the PFS24-RI included five risk factors: stage II or III/IV, elevated lactate dehydrogenase, Eastern Cooperative Oncology Group score ≥2, primary tumor invasion, and extra-upper aerodigestive tract. PFS24-RI stratified the patients into low-risk (0), intermediate-risk (1-2), high-risk (≥3) groups with different prognoses. Harrell's C-index of PFS24-RI for PFS24 prediction was 0.667 in the validation dataset, indicating a good discriminative ability. PFS24-RI calibration indicated that the actual observed and predicted probability of failing PFS24 agreed well. PFS24-RI provided the probability of achieving PFS24 at an individual patient level.

CAR-T cells targeting CD38 and LMP1 exhibit robust antitumour activity against NK/T cell lymphoma

BACKGROUND

Natural killer/T cell lymphoma (NKTCL) is an aggressive lymphoma with a poor prognosis. Chimeric antigen receptor-transduced T (CAR-T) cell therapy has become a promising immunotherapeutic strategy against haematologic malignancies.

METHODS

In this study, four CAR-T cell lines (CD38-CAR, LMP1-CAR, CD38-LMP1 tandem CAR 1 and CD38-LMP1 tandem CAR 2) were generated. The effect of CAR-T cells against NKTCL cells was evaluated both in vitro and in vivo. Expression of T cell activation markers and cytokines produced by CAR-T cells were detected by flow cytometry.

RESULTS

The four CAR-T cell lines could effectively eliminate malignant NKTCL cells. They could be activated and produce inflammatory cytokines in a target-dependent manner. In vivo tests showed that the CAR-T cells exhibited significant antitumour effects in a xenotransplanted NKTCL mouse model.

CONCLUSIONS

In summary, four CAR-T cell lines exhibited significant cytotoxicity against NKTCL cells both in vitro and in vivo. These results indicated the effective therapeutic promise of CD38 and LMP1 CAR-T cells in NKTCL.

Extranodal NK-/T-cell lymphoma, nasal type: what advances have been made in the last decade?

Extranodal NK-/T-cell lymphoma (ENKTCL) is a rare and highly aggressive malignancy with significant racial and geographic variations worldwide. In addition to the formerly "nasal-type" initial description, these lymphomas are predominantly extranodal in origin and typically cause vascular damage and tissue destruction, and although not fully understood, Epstein-Barr virus (EBV) has an important role in its pathogenesis. Initial assessment must include a hematopathology review of representative and viable tumor areas without necrosis for adequate immunohistochemistry studies, including EBV-encoded small RNA (EBER) in situ hybridization (ISH). Positron emission tomography with 18-fluorodeoxyglucose (¹⁸F-FDG-PET/CT) for accurate staging is essential, and most patients will have localized disease (IE/IIE) at diagnosis. Apart from other T-cell malignancies, the best treatment even for localized cases is combined modality therapy (chemotherapy plus radiotherapy) with non-anthracycline-based regimens. For advanced-stage disease, l-asparaginase-containing regimens have shown improved survival, but relapsed and refractory cases have very poor outcomes. Nowadays, even with a better understanding of pathogenic pathways, up-front therapy is completely based on chemotherapy and radiotherapy, and treatment-related mortality is not low. Future strategies targeting signaling pathways and immunotherapy are evolving, but we need to better identify those patients with dismal outcomes in a pre-emptive way. Given the rarity of the disease, international collaborations are urgently needed, and clinical trials are the way to change the future.

A Case Report of Extranodal NK/T-Cell Lymphoma Misdiagnosed as Meibomitis

INTRODUCTION

Extranodal natural killer/T-cell lymphoma (ENKTL) is a rare type of non-Hodgkin's lymphoma. This report presents a patient with the right lower eyelid ENKTL misdiagnosed as meibomitis repeatedly.

CASE PRESENTATION

A 48-year-old woman developed recurrent redness and swelling in right eyelid for 2 years. Three eyelid mass removal operations were performed in local hospitals, and the pathological examination suggested meibomitis. Physical examination showed an induration in the lateral lower eyelid of the right eye, local defect of the eyelid margin, mild entropion, redness and swelling of the surrounding tissues, and temporal bulbar conjunctiva hyperemia. The eyelid lesion was resected and ENKTL was diagnosed by specific immunohistochemical staining and in situ hybridization. The lymphoma resolved with chemotherapy and radiotherapy. The patient was still alive forty-one months after the last operation.

CONCLUSION

Our report demonstrates that recurrent eyelid redness and swelling might be a malignant tumor, and clinicians should be vigilant.

Etoposide, dexamethasone, and pegaspargase with sandwiched radiotherapy in early-stage natural killer/T-cell lymphoma: A randomized phase III study

Methotrexate, etoposide, dexamethasone, and pegaspargase (MESA) with sandwiched radiotherapy is known to be effective for early-stage extranodal natural killer/T-cell lymphoma, nasal type (NKTCL). We explored the efficacy and safety of reduced-intensity, non-intravenous etoposide, dexamethasone, and pegaspargase (ESA) with sandwiched radiotherapy. This multicenter, randomized, phase III trial enrolled patients aged between 14 and 70 years with newly diagnosed early-stage nasal NKTCL from 27 centers in China. Patients were randomly assigned (1:1) to receive ESA (pegaspargase 2,500 IU/m² intramuscularly on day 1, etoposide 200 mg orally, and dexamethasone 40 mg orally on days 2-4) or MESA (methotrexate 1 g/m² intravenously on day 1, etoposide 200 mg orally, and dexamethasone 40 mg orally on days 2-4, and pegaspargase 2,500 IU/m² intramuscularly on day 5) regimen (four cycles), combined with sandwiched radiotherapy. The primary endpoint was overall response rate (ORR). The non-inferiority margin was -10.0%. From March 16, 2016, to July 17, 2020, 256 patients underwent randomization, and 248 (ESA [n = 125] or MESA [n = 123]) made up the modified intention-to-treat population. The ORR was 88.8% (95% confidence interval [CI], 81.9-93.7) for ESA with sandwiched radiotherapy and 86.2% (95% CI, 78.8-91.7) for MESA with sandwiched radiotherapy, with an absolute rate difference of 2.6% (95% CI, -5.6-10.9), meeting the non-inferiority criteria. Per-protocol and sensitivity analysis supported this result. Adverse events of grade 3 or higher occurred in 42 (33.6%) patients in the ESA arm and 81 (65.9%) in the MESA arm. ESA with sandwiched radiotherapy is an effective, low toxicity, non-intravenous regimen with an outpatient design, and can be considered as a first-line treatment option in newly diagnosed early-stage nasal NKTCL.

Derivation and validation of a nutrition-covered prognostic scoring system for extranodal NK/T-cell lymphoma

Introduction

Patients with aggressive lymphomas are at high risk of losing body resources, resulting in malnutrition, immunodeficiency and inferior outcomes. Nutritional status is closely associated with survival, but often neglected in the prognostic assessment. This study aimed to explore the significance of nutritional status in extranodal NK/T-cell lymphoma (ENKTL).

Methods

Univariate and multivariate Cox regression analyses were conducted to examine the significance of nutritional index on overall survival (OS) and progression-free survival (PFS). A nutrition-incorporated score system was constructed based on the multivariate results, and its calibration, discrimination and clinical utility were tested in the training and validation cohort.

Results

Multivariate analysis revealed controlling nutritional status (CONUT) score could independently predict OS (HR 10.247, P=0.001) and PFS (HR 5.587, P=0.001) in addition to prognostic index of natural killer lymphoma plus EBV (PINK-E). Herein, a reformative model, CONUT-PINK-E, was developed and further verified in external validation cohort. CONUT-PINK-E classified patients into three risk grades with significant survival differences (P < 0.001). Compared with the current models, CONUT-PINK-E presented superior discrimination, calibration and clinical benefit.

Discussion

In this study, we firstly verified that CONUT score was efficient to screen prognosis-related malnutrition in ENKTL. Moreover, we developed the first nutritional assessment-covered scoring system, CONUT-PINK-E, which might be a promising tool to provide references for clinical decision-making of ENKTL patients.

Diagnostic and prognostic value of pretreatment PET/CT in extranodal natural killer/T-cell lymphoma: a retrospective multicenter study

PURPOSE

The objective of this research was to assess the utility of positron emission tomography combined with computed tomography (PET/CT) to detect bone marrow invasion (BMI) and the predictive value of PET/CT in extranodal natural killer/T-cell lymphoma (ENKTL) patients.

PATIENTS AND METHODS

This multicentre study enrolled ENKTL patients who underwent pretherapy PET/CT and bone marrow biopsy (BMB). The specificity, sensitivity, negative predictive value (NPV), and positive predictive value (PPV) of PET/CT and BMB for BMI were evaluated. Multivariate analysis was used to identify predictive parameters for constructing a nomogram.

RESULTS

Seven hundred and forty-eight patients were identified from four hospitals, with eighty (10.7%) having focal skeletal lesions on PET/CT and fifty (6.7%) having positive BMB. When BMB is considered as the gold standard, the specificity, sensitivity, PPV, and NPV of PET/CT for diagnosing BMI were found to be 93.8%, 74.0%, 46.3%, and 98.1%, respectively. PET/CT-positive individuals showed significantly worse OS than PET/CT-negative patients in the subgroup of BMB-negative cases. The nomogram model created according to the significant risk factors from multivariate analysis performed well in predicting survival probability.

CONCLUSION

PET/CT offers a superior degree of precision for determining BMI in ENKTL. A nomogram model including the parameters of PET/CT can predict survival probability and may help in applying appropriate personalized therapy.

The emerging role of anti-PD-1 antibody-based regimens in the treatment of extranodal NK/T-cell lymphoma-associated hemophagocytic lymphohistiocytosis

PURPOSE

Anti-PD-1 antibody (anti-PD-1 mAb) showed favorable outcomes in some patients with relapsed/refractory (r/r) extranodal NK/T-cell lymphoma (ENKTL). However, the role of anti-PD-1 antibody in NK/T-cell lymphoma-associated hemophagocytic lymphohistiocytosis (NK/T-LAHS) remains unclear. Here, we evaluated the efficacy and toxicity of anti-PD-1 antibody-based treatment in NK/T-LAHS patients.

METHODS

The clinical data of 98 patients diagnosed with NK/T-LAHS at Sun Yat-sen University Cancer Center and the First Affiliated Hospital of Guangdong Pharmaceutical University from May 2014 to November 2021 were retrospectively analyzed. All patients received anti-HLH [HLH-2004 (etoposide, dexamethasone, cyclosporine A) or DEP-based (liposomal doxorubicin, etoposide, methylprednisolone)] regimen and sequential anti-ENKTL chemotherapy (ChT) combined with anti-PD-1 antibody or not.

RESULTS

The overall response rate (ORR) of the anti-PD-1 mAb plus ChT regimens was higher than that of the ChT regimens (73.3% vs. 45.5%, P = 0.041). The toxicity of the anti-PD-1 mAb plus ChT regimens was tolerable. Except for higher rate of neutropenia, no significant difference in adverse events (AEs) was observed between the two groups. When the optimal response to anti-ENKTL was achieved, the median EBV DNA levels in patients who received anti-PD-1 mAb plus ChT were significantly lower than patients who received ChT only (878 copies/mL vs. 18,600 copies/mL, P = 0.001). With a median follow-up of 26.6 months (range 0-65.9 months), the median overall survival (mOS) was 3.5 months (95% CI：2.3-4.7 months). Patients treated with anti-PD-1 mAb plus ChT experienced a longer mOS than those who received ChT only [5.2 months (95% CI: 2.5-7.8 months) vs. 1.5 months (95% CI: 0.5-2.6 months), P = 0.002]. Cox multivariate analysis found that anti-PD-1 mAb was an independent prognostic factor for all NK/T-LAHS patients.

CONCLUSION

In conclusion, anti-PD-1 mAb combined with ChT regimens seemed to be associated with prolonged survival in NK/T-LAHS patients and may represent a potentially promising treatment strategy for this population.

An update on viral-induced cutaneous lymphoproliferative disorders. CME Part I

Viral-induced cutaneous T-cell lymphomas are an uncommon group of lymphoproliferative disorders characterized by a viral infection of T and natural killer (NK) cells. This group of cutaneous T-cell lymphomas is more commonly encountered in Asians and Native Americans from Central and South America compared with Western populations. Viral-associated lymphoproliferative disorders include a spectrum of entities that range from nonneoplastic lesions, such as chronic active Epstein-Barr virus infection and infective dermatitis to malignant diseases, such as extranodal NK/T-cell lymphoma, hydroa vacciniforme-like T-cell lymphoma, and adult T-cell leukemia/lymphoma. This review article will focus on hydroa vacciniforme-like lymphoproliferative disorder, extranodal NK/T-cell lymphoma, adult T-cell leukemia/lymphoma, lymphomatoid granulomatosis, and Epstein-Barr virus-positive mucocutaneous ulcers. We will review the pathogenesis of these conditions and the challenges of making a timely diagnosis in early-stage disease and discuss the common clinicopathologic manifestations, mutational landscape, and approaches to treat these highly aggressive and frequently lethal types of lymphoma.

Toxicity of a Modified PEG-Asparaginase-Based SMILE Regimen Is Comparable to L-Asparaginase-Based SMILE in a Non-Asian Population

INTRODUCTION

L-asparaginase-based chemotherapy regimens are effective for treating chemotherapy-resistant natural killer- (NK-) cell neoplasms. To treat these lymphoma subtypes in Asia, where NK/T-cell lymphomas are more prevalent, the NK-Cell Tumor Study Group developed the SMILE regimen, which includes a steroid, methotrexate, ifosfamide, L-asparaginase, and etoposide. In the US however, the only commercially available form of asparaginase is the pegylated form (PEG-asparaginase) which has been incorporated into a modified SMILE (mSMILE). We sought to study the toxicity associated with replacing L-asparaginase with PEG-asparaginase in mSMILE.

PATIENTS AND METHODS

We retrospectively identified all adult patients treated with the mSMILE chemotherapy regimen in our database at Moffitt Cancer Center (MCC) between December 1, 2009, and July 30, 2021. Patients were included if they were treated with mSMILE irrespective of their underlying diagnosis. Toxicity was assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 5. The rate of toxicity in our mSMILE treatment group was numerically compared to data published in a metanalysis of the SMILE regimen's toxicity (Pokrovsky et al., 2019).

RESULTS

A total of 21 patients were treated with mSMILE at MCC during the 12-year analysis window. Compared to patients receiving the L-asparaginase-based SMILE, patients receiving mSMILE experienced grade 3 or 4 leukopenia less often, with a toxicity rate of 62% (median with SMILE, 85% [95% CI, 74%-95%]); thrombocytopenia, however, was more common, with a toxicity rate of 57% (median with SMILE, 48% [95% CI, 40%-55%]). Other hematological, hepatic and coagulation related toxicities were also reported.

CONCLUSION

In a non-Asian population, the mSMILE regimen with PEG-asparaginase is a safe alternative to the L-asparaginase-based SMILE regimen. There is a comparable risk of hematological toxicity, and no treatment-related mortality was seen in our population.

Clinicopathological and molecular features of indolent natural killer-cell lymphoproliferative disorder of the gastrointestinal tract

AIMS

Indolent natural killer (NK) cell lymphoproliferative disorder of the gastrointestinal (GI) tract (iNKLPD) is a rare, recently recognised neoplasm. Most of the reported tumours are confined to the GI tract, while a small subset of the tumours harbour JAK3 mutations. We collected four cases of iNKLPD with the goal of adding additional information to the current knowledge of this disease regarding the clinicopathological, immunohistochemical and molecular features.

METHODS AND RESULTS

Similar features including medium- to large-sized lymphoid cells with variable amounts of pale or slightly eosinophilic cytoplasm, and no evidence of EBER, TCR rearrangement were found in four cases. JAK3 K563_C565del mutation was found in one of three cases that were subjected to targeted next-generation sequencing. Unique findings of our study include one iNKLPD encountered for the first time in nasopharynx, where lesions could be inadvertently diagnosed as extranodal NK/T cell lymphoma, and one iNKLPD located in the gallbladder extended deeply into muscular and adventitial layers. Exceptional CD8-positive expression was observed in one iNKLPD. In addition, positive staining of phospho-STAT5, phospho-STAT3 and phospho-p38 were found in our cases. None of the four patients received therapy for lymphoma, but all had a benign clinical outcome during a follow-up time of 20-99 months.

CONCLUSIONS

We present four iNKLPDs with clinical, immunohistochemical and molecular features similar to the reported cases, as well as some unusual characters, which expand our knowledge on this disease, and further support the neoplastic nature of iNKLPDs.

Clinical and Pathological Features of Hydroa Vacciniforme-Like Lymphoproliferative Disorder Along with Risk Factors Indicating Poor Prognosis

Purpose

To examine the clinical and pathological features, laboratory markers, therapeutic options and risk factors indicating poor prognosis of hydroa vacciniforme-like lymphoproliferative disorder (HVLPD).

Patients and Methods

Seven patients with HVLPD had their clinical and pathological data collected. Immunohistochemical staining, Epstein-Barr virus-encoded RNA (EBER) in situ hybridization experiments, T-cell receptor (TCR) gene rearrangement, RT-PCR tests and the Elisa assay were carried out.

Results

The main clinical manifestations were papulovesicular lesions and ulcers on the face, neck, or trunk. Five cases had systemic symptoms. Three of the deceased patients had significant facial edema, deep body necrosis, and ulceration. The pathological results demonstrated that lymphocytes infiltrated blood vessels and sweat glands in addition to the dermis and subcutaneous tissues. All patients tested positive for CD3 and EBER. Six cases tested positive for TCRβF1, but none tested positive for TCRδ. TCRγ monoclonal rearrangement, strongly positive expression of TIA-1 and a Ki67 proliferation index of 40% occurred in 3 fatal cases. When compared to the survival group, the plasma EBV DNA in the deceased group was considerably higher (P<0.05). IFN-γ and TNF-α cytokine levels in patients were higher than in the control group, particularly in the deceased group (P<0.05). The skin lesions on all patients recovered quickly underwent conservative care. Nonetheless, 3 patients passed away as the disease progressed in its latter stages.

Conclusion

In our cases, the main infiltrating cells were T cells and the dominant lymphocyte subclass was αβT cells. A significant increase in lgE level, plasma EBV DNA, IFN-γ, and TNF-α cytokine levels, decreased hemoglobin level, strongly positive expression of TIA-1, high Ki67 proliferation index, and positive TCR gene rearrangement are all indicators of a poor prognosis.

Treatment of extranodal NK/T-cell lymphoma: From past to future

Extranodal NK/T-cell lymphoma (ENKTCL) is the most common subtype of T/NK-cell lymphoma in Asia and Latin America, but very rare in North American and Europe. Patient survival has improved significantly over the past two decades. However, standard treatment has not yet been established, although dozens of prospective trials have been conducted. To help understand how the treatment of ENKTCL has evolved in the past and what trends lie ahead, we have comprehensively reviewed the treatment of this aggressive malignancy, with a particular focus on neglected or unanswered issues, such as the optimal staging method, the best partner of asparaginase (Asp), the individualized administration of Asp, the preferred sequence of CT and RT and so on. Overall, the 5-year overall survival (OS) of patients with Ann Arbor stage I/II disease increased from < 50% in the early 20th century to > 80% in recent years, and the median OS of patients with Ann Arbor stage III/IV disease increased from < 1 year to more than 3 years. The improvement in patient survival is largely attributable to advances in radiation technology and the introduction of Asp and anti-PD-1/PD-L1 immunotherapy into practice. Radiotherapy is essential for patients with early-stage disease, while Asp-based chemotherapy (CT) and PD-1/PD-L1 inhibitors significantly improved the prognosis of patients with advanced-stage disease. ENKTCL management is trending toward simpler regimens, less toxicity, and higher efficacy. Novel drugs, such as manufactured T cells, monoclonal antibodies, and small molecule inhibitors, are being intensively investigated. Based on the fact that ENKTCL is highly resistant to cytotoxic drugs except Asp, and aggressive CT leads to higher toxicity rather than better outcomes, we recommend it is unnecessary to expend additional resources to compare different combinations of Asp with cytotoxic agents. Instead, more efforts should be made to optimize the use of Asp and immunotherapy to maximize efficacy and minimize toxicity, explore ways to overcome resistance to Asp and immunotherapy, identify novel treatment targets, and define subpopulations who may benefit more from specific treatments.

Bilateral intraocular and lung involvements associated with Nasal NK/T-cell lymphoma

BACKGROUND

To report a rare case of nasal natural killer/T (NK/T) cell lymphoma with bilateral intraocular and lung metastasis and to further describe the clinical features of intraocular manifestations.

CASE PRESENTATION

A 54-year-old man presented with a 3-month history of left nasal congestion, and bilateral vision impairment of one week duration. Subsequent maxillary computed tomography (CT) and multiple biopsies confirmed the diagnosis of nasal NK/T-cell lymphoma. EBV-encoded small RNA (EBER) in situ hybridization revealed EBV infection. A comprehensive ophthalmic examination found lymphoma-associated retinopathy and choroidopathy, which presented as bilateral diverse patterns and retinal detachment. In addition, the chest CT showed multiple scattered nodules in both lungs, and soft-tissue mass in the left hilum with mediastinal and axillary lymphadenopathy. The condition of this patient deteriorated rapidly and he died shortly after diagnosis.

CONCLUSIONS

The rarity of secondary ocular NK/T-cell lymphoma makes it challenging to identify these tumors early. Both otolaryngologist and ophthalmologists should be aware of ocular involvement and other secondary manifestations of NK/T-cell lymphoma.

Extranodal T- and NK-cell lymphomas

Non-cutaneous extranodal NK/T cell lymphoproliferations constitute a heterogenous group of rare neoplasms, occurring primarily in the gastro-intestinal tract, nasal area, spleen, and liver. Their nomenclature refers to their usual clinical presentation and predilection for specific anatomic sites-i.e. extranodal NK/T-cell lymphoma, nasal-type, hepatosplenic T-cell lymphoma, primary intestinal T-cell lymphomas, indolent lymphoproliferative disorders of the gastrointestinal tract, and breast implant-associated anaplastic large cell lymphoma. Extranodal tissues may also be involved by T-cell leukemias, or other entities usually presenting as nodal diseases. Primary extranodal entities range from indolent to highly aggressive diseases. Here, we will review the clinicopathologic features of the pertinent entities including the recent advances in their molecular and genetic characterization, with an emphasis on the changes introduced in the 2022 International Consensus Classification of lymphoid neoplasms, and highlight the diagnostic criteria helpful to sort out the distinction with potential mimickers.

The Novel Prognostic Index Model of Combining Circulating Tumor DNA and PINK-E Predicts the Clinical Outcomes for Newly Diagnosed Extranodal NK/T-cell Lymphoma

Extranodal NK/T-cell lymphoma (ENKTL) is a highly aggressive and heterogeneous disease with poor clinical outcome. Our previous work had demonstrated that circulating tumor DNA (ctDNA) analyses were feasible in ENKTL, and dynamic tracing of ctDNA could be used to monitor the disease status. However, the prognostic value of ctDNA in ENKTL has not been fully investigated. Patients with newly diagnosed ENKTL from February 2017 to December 2021 (n = 70) were enrolled. The pretreatment ctDNA concentration (hGE/mL) was measured. The prognostic value of ctDNA, international prognostic index (IPI), Korean prognostic index (KPI), PINK-E, and the combination of PINK-E and ctDNA (PINK-EC) were investigated in our cohort. The IPI and PINK-E risk categories had a significant difference in progression-free survival (PFS) and overall survival (OS) between the low-risk and intermediate-risk groups. The KPI risk category had a difference in PFS and OS between the intermediate-risk and high-risk groups. Furthermore, integrating ctDNA into the PINK-E model could overcome the shortcomings of other prognostic models, which could significantly distinguish the different-risk groups. Overall, our results demonstrated that PINK-EC showed a superior prognostic prediction value and stability compared with IPI, KPI, and PINK-E. The integration of molecular features of the tumor into classic risk categories might better characterize a high-risk group where novel treatment approaches are most needed.

The spectrum of intestinal mature T- and NK-cell neoplasms in a tertiary center in Taiwan with a high frequency of perforation

Primary intestinal T-cell lymphomas (PITLs) comprise enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), extranodal NK/T-cell lymphoma (ENKTL), anaplastic large cell lymphoma (ALCL), and intestinal T cell lymphoma, NOS (ITCL-NOS). MEITL is composed of monomorphic medium cells expressing CD8 and CD56, with a cytotoxic phenotype. We retrospectively analyzed 77 cases of intestinal T-cell lymphomas, 71 primary and six secondary, at a tertiary center in Taiwan from 2001 to 2021. Perforation occurred in 57 (74%) patients, including 56 (73%) at presentation and one after chemotherapy. The primary cases included MEITL (68%), ENKTL (14%), ITCL-NOS (13%), ALCL (4%), and EATL (1%). The perforation rate was 90%, 70%, and 22% in MEITL, ENKTL, and ITCL-NOS cases, respectively (p < 0.0001, Fisher's exact test). Most (75%; n = 36) MEITL cases were typical; while seven (15%) had atypical morphology and five (10%) exhibited atypical immunophenotype. The tumor cells of ITCL-NOS were pleomorphic, with various expression of CD8 or CD56. All METIL, ITCL-NOS and ALCL cases were negative for EBER; while all ENKTL cases, either primary or secondary, were positive for cytotoxic granules and EBER. The prognosis of PITL was poor, with a medium survival of 7.0, 3.3, and 3.7 months among patients with MEITL, ENKTL, and ITCL-NOS, respectively. Of the six secondary cases, the primary tumors orginated from nasal ENKTL (n = 5) and cutaneous PTCL-NOS (n = 1). We showed a wide spectrum of intestinal T-cell lymphomas in Taiwan, with MEITL as the most common PITL, a high rate of perforation, and a wider morphological and immunophenotypic spectrum.

Primary Orbital Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type, without Nasal Involvement

Extranodal natural killer/T-cell lymphoma (ENKL) usually occurs in the nose or the nasopharynx, but extranasal and disseminated disease can occur. In this disease, orbital involvement is more commonly seen, but without nasal involvement is rare. A 61-year-old woman was referred with a one-month history of a remarkably enlarging salmon-colored mass arising in the right inner canthus, with redness and painlessness. The motility of the right eye was limited in the medial direction, with external deviation of the eyeball. A magnetic resonance imaging (MRI) scan of the orbits showed a mass of irregular shape located in the right inner canthus, without any sinus involvement. A histopathological examination concluded a diagnosis of primary orbital extranodal natural killer/T-cell lymphoma, nasal type. Her orbital mass significantly reduced to near disappeared after chemotherapy. From the first visit to the present, the survival duration of this patient was more than 1 year. This patient was still alive with a high quality of life and with no systemic metastasis. Extranodal natural killer/T-cell lymphoma, nasal type may primarily arise in the orbit without nasal involvement. Early discovery, early biopsy and diagnosis and early appropriate treatment can successfully control tumors and improve prognosis.

Intravascular NK/T-Cell Lymphoma: What We Know about This Diagnostically Challenging, Aggressive Disease

Intravascular lymphoma is a form of lymphoid malignancy characterized by neoplastic cells growing almost exclusively within the lumina of small- to medium-sized blood vessels. Most cases are of B-cell origin with rare cases of natural killer or T-cell lineage. Extranodal sites are affected, mainly the skin and central nervous system, although any organ may be involved. Intravascular NK/T-cell lymphoma deserves special attention because of its clinicopathologic features and the need for adequate immunophenotyping combined with clonality test for a proper diagnosis. Moreover, intravascular NK/T-cell lymphoma is strongly linked to Epstein-Barr virus (EBV), which is considered to play a role in tumorigenesis and to be responsible for the aggressive behavior of the disease. In this paper, we review the current knowledge on this rare lymphoma and, in particular, the most recent advances about its molecular landscape. The main distinguishing features with other EBV-related entities, such as extranodal NK/T-cell lymphoma, EBV-positive primary nodal T/NK-cell lymphoma, and aggressive NK-cell leukemia, are discussed to help pathologists obtain the correct diagnosis and consequently develop an adequate and prompt therapy response.

Genomic profiling identifies distinct genetic subtypes in extra-nodal natural killer/T-cell lymphoma

Extra-nodal NK/T-cell lymphoma, nasal type (ENKTCL) is a highly aggressive Epstein-Barr virus associated lymphoma, typically presenting in the nasal and paranasal areas. We assembled a large series of ENKTCL (n = 209) for comprehensive genomic analysis and correlative clinical study. The International Lymphoma Prognostic Index (IPI), site of disease, stage, lymphadenopathy, and hepatomegaly were associated with overall survival. Genetic analysis revealed frequent oncogenic activation of the JAK/STAT3 pathway and alterations in tumor suppressor genes (TSGs) and genes associated with epigenomic regulation. Integrated genomic analysis including recurrent mutations and genomic copy number alterations using consensus clustering identified seven distinct genetic clusters that were associated with different clinical outcomes, thus constituting previously unrecognized risk groups. The genetic profiles of ENTKCLs from Asian and Hispanic ethnic groups showed striking similarity, indicating shared pathogenetic mechanism and tumor evolution. Interestingly, we discovered a novel functional cooperation between activating STAT3 mutations and loss of the TSG, PRDM1, in promoting NK-cell growth and survival. This study provides a genetic roadmap for further analysis and facilitates investigation of actionable therapeutic opportunities in this aggressive lymphoma.

18F-FDG PET/CT Plays a Limited Role in Replacing Bone Marrow Biopsy for Newly Diagnosed Advanced-Stage Patients With Extranodal Natural Killer/T-Cell Lymphoma

Purpose

The role of ¹⁸F-2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in evaluating bone marrow (BM) involvement (BMI) among patients with extranodal natural killer/T-cell lymphoma (ENKTL) is poorly understood. This study investigated whether PET/CT could replace bone marrow biopsy (BMB) in treatment-naive ENKTL patients.

Methods

Newly diagnosed ENKTL patients (n = 356) who received BMB and PET/CT to evaluate BMI at the time of diagnosis were retrospectively reviewed at West China Hospital between August 2008 and January 2020. The BMI diagnosis was confirmed using BM histology. Clinical characteristics, survival outcomes, and prognostic indicators were summarized and analyzed.

Results

The cohort included 356 cases, of whom 261 were diagnosed with early-stage and 95 with advanced-stage ENKTL by PET/CT before initial treatment. No early-stage patients were identified with BMI by either BMB or PET/CT. Among the advanced-stage patients, 26 were BMB positive, and 12 of 22 patients (54.5%) with positive PET/BM results were also BMB positive. The sensitivity and specificity of PET/CT to detect BMI were 46% and 97%, respectively. The progression-free survival (PFS) and overall survival (OS) of PET/BM-negative patients were markedly longer (p = 0.010 and p = 0.001 for PFS and OS, respectively), which was consistent with the results of the BMB (p = 0.000 for both PFS and OS).

Conclusion

Although ¹⁸F-FDG PET/CT showed the potential to replace BMB in the initial staging of early-stage ENKTL patients, baseline PET/CT cannot provide an accurate BMI evaluation for advanced-stage patients. A prospective study is required to confirm the diagnostic performance of BMI identification by PET/CT, along with targeted BMB and MRI for advanced-stage patients.

A genomic-augmented multivariate prognostic model for the survival of Natural-killer/T-cell lymphoma patients from an international cohort

With lowering costs of sequencing and genetic profiling techniques, genetic drivers can now be detected readily in tumors but current prognostic models for Natural-killer/T cell lymphoma (NKTCL) have yet to fully leverage on them for prognosticating patients. Here, we used next-generation sequencing to sequence 260 NKTCL tumors, and trained a genomic prognostic model (GPM) with the genomic mutations and survival data from this retrospective cohort of patients using LASSO Cox regression. The GPM is defined by the mutational status of 13 prognostic genes and is weakly correlated with the risk-features in International Prognostic Index (IPI), Prognostic Index for Natural-Killer cell lymphoma (PINK) and PINK-Epstein-Barr virus (PINK-E). Cox-proportional hazard multivariate regression also showed that the new GPM is independent and significant for both progression-free survival (PFS, HR: 3.73, 95% CI 2.07-6.73; P<0.001) and overall survival (OS, HR: 5.23, 95% CI 2.57-10.65; P=0.001) with known risk-features of these indices. When we assign an additional risk-score to samples, which are mutant for the GPM, the Harrell's C-indices of GPM-augmented IPI, PINK and PINK-E improved significantly (P<0.001, χ² test) for both PFS and OS. Thus, we report on how genomic mutational information could steer towards better prognostication of NKTCL patients. This article is protected by copyright. All rights reserved.

The Role of PD-L1 Expression in Prediction and Stratification of Recurrent or Refractory Extranodal Natural Killer/T-Cell Lymphoma

Background and Aims

The clinical outcome of relapsed and refractory (RR) extranodal natural killer/T-cell lymphoma (ENKTL) is poor. It is necessary to identify RR patients in ENKTL and find novel therapeutic targets to improve the prognosis of patients with RR ENKTL.

Methods

A total of 189 ENKTL patients with effective clinical characteristics were enrolled. Paraffin specimens were collected for PD-L1 expression identification. Kaplan-Meier curve analysis was performed for survival analysis. Whole exome sequencing (WES) was performed for identifying the mutational characterization of RR and effective treatment (ET) patients.

Results

Univariate and multivariate Cox proportional hazards regression analysis showed that negative PD-L1 expression (HR = 1.132, 95% CI = 0.739-1.734, P = 0.036) was an independent predictor of poor prognosis in patients with ENKTL. The overall survival (OS) of PD-L1 positive patients was significantly higher than that of PD-L1 negative patients (P = 0.009). Then, we added PD-L1 expression as a risk factor to the model of Prognostic Index of Natural Killer Lymphoma (PINK), and named as PINK+PD-L1. The PINK+PD-L1 model can significantly distinguish RR patients, ET patients, and the whole cohort. Moreover, our data showed that PD-L1 expression was lower than 25% in most RR patients, suggesting that RR subtypes may be associated with low expression of PD-L1 (P = 0.019). According to the whole exome sequencing (WES), we found that the mutation frequencies of JAK-STAT (P = 0.001), PI3K-AKT (P = 0.02) and NF-kappa B (P < 0.001) pathways in RR patients were significantly higher than those in ET patients.

Conclusion

Patients tend to show RR when PD-L1 expression is lower than 25%. The model of PINK+PD-L1 can stratify the risk of different groups and predict OS in ENKTL patients. The mutational profile of ENKTL patients with RR is different from that of patients with ET.

Cellular Origins and Pathogenesis of Gastrointestinal NK- and T-Cell Lymphoproliferative Disorders

The intestinal immune system, which must ensure appropriate immune responses to both pathogens and commensal microflora, comprises innate lymphoid cells and various T-cell subsets, including intra-epithelial lymphocytes (IELs). An example of innate lymphoid cells is natural killer cells, which may be classified into tissue-resident, CD56bright NK-cells that serve a regulatory function and more mature, circulating CD56dim NK-cells with effector cytolytic properties. CD56bright NK-cells in the gastrointestinal tract give rise to indolent NK-cell enteropathy and lymphomatoid gastropathy, as well as the aggressive extranodal NK/T cell lymphoma, the latter following activation by EBV infection and neoplastic transformation. Conventional CD4+ TCRαβ+ and CD8αβ+ TCRαβ+ T-cells are located in the lamina propria and the intraepithelial compartment of intestinal mucosa as type 'a' IELs. They are the putative cells of origin for CD4+ and CD8+ indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and intestinal T-cell lymphoma, NOS. In addition to such conventional T-cells, there are non-conventional T-cells in the intra-epithelial compartment that express CD8αα and innate lymphoid cells that lack TCRs. The central feature of type 'b' IELs is the expression of CD8αα homodimers, seen in monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), which primarily arises from both CD8αα+ TCRαβ+ and CD8αα+ TCRγδ+ IELs. EATL is the other epitheliotropic T-cell lymphoma in the GI tract, a subset of which arises from the expansion and reprograming of intracytoplasmic CD3+ innate lymphoid cells, driven by IL15 and mutations of the JAK-STAT pathway.

Extranodal Natural Killer/T-Cell Lymphomas: Current Approaches and Future Directions

Extranodal natural killer/T(NK/T)-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma that typically presents with an isolated nasal mass, but a sizeable minority present with advanced stage disease and have a significantly poorer prognosis. Those with limited disease are standardly treated with chemotherapy and radiation while those with advanced stage disease are treated with L-asparaginase containing chemotherapy regimens. The addition of modern radiation therapy techniques and the incorporation of L-asparaginase into chemotherapy regimens have significantly improved outcomes in this disease, but relapses and death from relapsed disease remain frequent. Given the high rate of relapse, several novel therapies have been evaluated for the treatment of this disease. In this review, we explore the current standard of care for ENKTL as well as novel therapies that have been evaluated for its treatment and the biologic understanding behind these therapies.