[Efficacy and safety analysis of P-GemDOx regimen and stratified prognosis in patients with early extranodal NK/T cell lymphoma].

Objective: To assess the efficacy, safety, and related prognostic factors associated with the P-GemDOx regimen as a first-line treatment for patients with early-stage extranodal natural killer (NK) /T cell lymphoma (ENKTL) . Methods: A retrospective analysis was performed on sixty early-stage ENKTL patients treated with the P-GemDOx regimen who were admitted to the First Affiliated Hospital of Nanjing Medical University between August 2015 and May 2021. The Chi-square test or Fisher's exact test was used to compare group differences, and the Log-rank test was used to compare the differences in survival. Survival outcomes and prognostic factors were examined. Results: After completing 4 to 6 cycles of P-GemDOx chemotherapy, the overall response rate (ORR) was 88.3%, with forty-six patients (76.7% ) achieving complete response (CR). The 4-year progression-free survival (PFS) and overall survival (OS) rates were (66.3±7.1) % and (79.5±6.0) %, respectively. According to the PINK/PINK-E model, there was no significant difference in survival outcomes among risk groups. 23.3% of patients experienced progression of disease within 24 months (POD<24). OS estimates differed significantly (P<0.001) between the POD<24 group (n=14) and the POD≥24 group (n=46). Analysis showed that SUVmax > 12.8 at diagnosis, non-single nasal cavity infiltration, and response less than CR after 4-6 cycles all had a significant association with POD24. We used these data as the basis for predicting POD<24 international prognostic index (POD24-IPI). Patients were stratified into low-risk (no risk factors), intermediate-risk (one risk factor), or high risk (two or three risk factors). These groups were associated with 4-year OS rate of 100%, (85.6±9.7) %, and (65.0±10.2) %, respectively (P=0.014). The P-GemDOx regimen was well tolerated, with hematological toxicity being the main side effect. Conclusion: This study demonstrated that the P-GemDOx regimen is effective and safe in the first-line treatment of early-stage ENKTL, and POD24-IPI is a promising prognostic model.

Full-spectral genome analysis of natural killer/T cell lymphoma highlights impacts of genome instability in driving its progression.

BACKGROUND: Natural killer/T cell lymphoma (NKTCL) is a clinically and genetically heterogeneous disease with poor prognosis. Genome sequencing and mutation characterization provides a powerful approach for patient stratification, treatment target discovery, and etiology identification. However, previous studies mostly concentrated on base-level mutations in primary NKTCL, whereas the large-scale genomic alterations in NKTCL and the mutational landscapes in relapsed/refractory NKTCL remain largely unexplored. METHODS: Here, we assembled whole-genome sequencing and whole-exome sequencing data from 163 patients with primary or relapsed/refractory NKTCL and compared their somatic mutational landscapes at both nucleotide and structure levels. RESULTS: Our study not only confirmed previously reported common NKTCL mutational targets like STAT3, TP53, and DDX3X but also unveiled several novel high-frequency mutational targets such as PRDM9, DST, and RBMX. In terms of the overall mutational landscape, we observed striking differences between primary and relapsed/refractory NKTCL patient groups, with the latter exhibits higher levels of tumor mutation burden, copy number variants (CNVs), and structural variants (SVs), indicating a strong signal of genomic instability. Complex structural rearrangements such as chromothripsis and focal amplification are also significantly enriched in relapsed/refractory NKTCL patients, exerting a substantial impact on prognosis. Accordingly, we devised a novel molecular subtyping system (i.e., C0-C4) with distinct prognosis by integrating potential driver mutations at both nucleotide and structural levels, which further provides an informative guidance for novel treatments that target these specific driver mutations and genome instability as a whole. CONCLUSIONS: The striking differences underlying the mutational landscapes between the primary and relapsed/refractory NKTCL patients highlight the importance of genomic instability in driving the progression of NKTCL. Our newly proposed molecular subtyping system is valuable in assisting patient stratification and novel treatment design towards a better prognosis in the age of precision medicine.

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.

Extranodal NK/T-cell lymphoma with localized relapse in bone marrow of lower leg detected using PET-CT.

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma (NHL) with poor prognosis, particularly in relapsed or refractory patients. Thus, timely detection of relapse and appropriate disease management are crucial. We present two patients with ENKTL, wherein positron emission tomography-computed tomography (PET-CT) with total-body coverage after induction therapy, detected newly relapsed regions in the bone marrow of the lower leg prior to progression. Case 1: A 47-year-old woman with nasal obstruction, showing 18F-fluoro-deoxyglucose (FDG) uptake in the nasal cavity (Lugano stage IE). After induction therapy (RT-2/3 DeVIC), PET-CT revealed abnormal uptake only in the right fibula. Case 2: A 68-year-old man with a skin nodule/ulcer and an enlarged right inguinal lymph node was diagnosed with advanced ENKTL. A PET-CT scan revealed abnormal uptake in the subcutaneous mass of the right medial thigh, lymph nodes, and descending colon (Lugano stage IV). After induction therapy, PET-CT revealed new abnormal uptake only in the left tibia. In both patients, CT-guided biopsy confirmed ENKTL recurrence. Moreover, PET-CT with whole-body coverage was useful for the timely assessment of relapse and detection of asymptomatic bone involvement. This approach allowed for modifications to treatment strategies in certain patients.

Extranodal natural killer/T cell lymphoma nasal type simulating osteoradionecrosis with metachronic B lymphoma in the pelvis: Case report.

Extranodal Natural Killer/T Cell Lymphoma Nasal Type (EN-NK/T-CL-NT) is a non-Hodgkin extranodal lymphoma of unfavorable prognosis due to its aggressive nature. This neoplasm mainly affects the paranasal sinuses, nasopharynx, oropharynx, oral cavity, palate, and rarely intestinal, gastric and skin regions. 50-year-old female with a history of lymphoma in nasal and pelvic region. At four years of tumors-free, has facial asymmetry, accompanied by sub-palpebral, nasal and lip edema. Intraoral examination revealed a large ulceration suggestive of osteoradionecrosis. Gum biopsy shows Extranodal NK/T Cell Lymphoma Nasal Type (EN-NK/T-CL-NT). In this case we highlight the characteristics of EN-NK/T-CL-NT with a presentation of osteoradionecrosis-like. Unfortunately, the nature of this tumor led to the patient's death. Clinical follow-up of patients with cancer is imperative to mend and/or decrease treatment complications, as well as to identify second primary tumors or the spread of the underlying disease.

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.

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.

Immunotyping of peripheral blood lymphocytes by flow cytometry reveals Th cell as a potential prognostic biomarker for extranodal NK/T-cell lymphoma.

This study aimed to explore the distribution, characteristics and prognostic value of baseline peripheral blood lymphocyte subsets in patients with extranodal NK/T-cell lymphoma (NKTCL). We conducted this cross-sectional study of 205 newly-diagnosed NKTCL patients receiving first-line chemotherapy and radiation at our institute between 2010 and 2020. Baseline peripheral blood lymphocytes were detected using flow cytometry, and the clinical value was analyzed. Compared with healthy controls, patients with NKTCL presented with a distinct peripheral immunity with higher levels of cytotoxic CD8+ T cells (33.230 ± 12.090% vs. 27.060 ± 4.010%, p < 0.001) and NKT cells (7.697 ± 7.219% vs. 3.550 ± 2.088%, p < 0.001) but lower proportions of suppressive regulatory T cells (Treg, 2.999 ± 1.949% vs. 3.420 ± 1.051%, p = 0.003) and CD4+ helper T cells (Th, 33.084 ± 11.361% vs. 37.650 ± 3.153%, p < 0.001). Peripheral lymphocytes were differentially distributed according to age, stage, and primary site in patients with NKTCL. The proportion of Th cells/lymphocytes was associated with tumor burden reflected by stage (p = 0.037), serum lactate dehydrogenase (p = 0.0420), primary tumor invasion (p = 0.025), and prognostic index for NK/T-cell lymphoma (PINK) score (p = 0.041). Furthermore, elevated proportions of T cells (58.9% vs. 76.4%, p = 0.005), Th cells (56.3% vs. 68.8%, p = 0.047), or Treg cells (49.5% vs. 68.9%, p = 0.040) were associated with inferior 5-year progression-free survivals (PFS) via univariable survival analysis. Multivariate cox regression revealed elevated Th cells as an independent predictor for unfavorable PFS (HR = 2.333, 95% CI, 1.030-5.288, p = 0.042) in NKTCL. These results suggested the proportion of Th cells positively correlated with tumor burden and was a potential non-invasive biomarker for inferior survival for patients with NKTCL.

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 case of extranodal NK/T-cell lymphoma, nasal type, diagnosed by scraping cytology of the maxillary gingiva.

Extranodal NK/T-cell lymphoma (ENKTL), nasal type, is often seen in the head and neck region, but there have been rare instances of this disease with initial presentation as a lesion in the oral mucosa. The patient, a woman in her seventh decade of life, presented with an ulcer in the maxillary gingiva, and scraping cytology and biopsy were performed. Cytological specimens showed solitary or small aggregating cells with marked atypia in a necrotic background. Tumor cells were detected that had various nuclear shapes and azure granules in the cytoplasm. Biopsy showed that the tumor cells had diffusely infiltrated or interdigitated into the subepithelium. Immunohistochemistry revealed that the tumor cells had T- and NK cell phenotypes and were Epstein-Barr virus-encoded small RNA (EBER) positive, leading to a diagnosis of ENKTL. Thus, when nonepithelial tumor cells in a necrotic background and prominent atypia are found, as in this case, it is important to carefully observe for azurophil granules in the cytoplasm for differential diagnosis considerations.

Molecular and clinicopathological features of granzyme B-negative extranodal NK/T-cell lymphoma.

Extranodal NK/T-cell lymphoma (ENKTL) generally expresses cytotoxic molecules, including granzyme B (GZMB), T-cell-restricted intracellular antigen-1 (TIA-1), and perforin; however, the expression of these molecules varies across cases. We performed gene expression profiling and identified unique biological and clinicopathological features of GZMB-negative ENKTL. We reviewed the clinicopathological characteristics of 71 ENKTL samples. Gene expression profiling on nine ENKTLs using multiplexed, direct, and digital mRNA quantification divided ENKTLs into Groups A (n = 7) and B (n = 2) through hierarchical clustering and t-distributed stochastic neighbor embedding. Group B was characterized by downregulation of genes associated with IL6-JAK-STAT3 signaling and inflammatory responses. GZMB mRNA expression was significantly downregulated in Group B. GZMB protein expression was evaluated with immunohistochemistry in all 71 ENKTLs, and expression data of Tyr705-phosphorylated STAT3 (pSTAT3) and MYC from our previous study was utilized. T-cell receptor gamma (TRG) gene rearrangement in the selected samples was also assessed using PCR. GZMB expression was higher in pSTAT3-positive (p = 0.028) and MYC-positive (p = 0.014) ENKTLs. Eighteen percent (13/71) of all ENKTLs were negative for GZMB (defined by positivity <10 %); patients with GZMB-negative ENKTLs were often in a higher clinical stage (p = 0.016). We observed no other correlations with clinical parameters or TRG rearrangement and no significant association between GZMB expression and survival. In conclusion, GZMB expression is highly heterogeneous in ENKTLs and is associated with the activation of the JAK-STAT3 pathway and higher MYC expression. GZMB-negative ENKTLs correlate with an advanced clinical stage, suggesting the potential utility of GZMB immunohistochemistry as a biomarker of ENKTL.

Establishment of ganglioside GD2-expressing extranodal NK/T-cell lymphoma cell line with scRNA-seq analysis.

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKL), is characterized by Epstein-Barr virus infection and poor prognosis. We established a novel cell line, ENKL-J1, from bone marrow cells of an ENKL patient. We found that ENKL-J1 cells express the ganglioside GD2 (GD2) and that GD2-directed chimeric antigen receptor T cells exhibit cytotoxicity against ENKL-J1 cells, indicating that GD2 would be a suitable target of GD2-expressing ENKL cells. Targeted next-generation sequencing revealed TP53 and TET2 variants in ENKL-J1 cells. Furthermore, single-cell RNA sequencing in ENKL-J1 cells showed high gene-expression levels in the oncogenic signaling pathways JAK-STAT, NF-κB, and MAPK. Genes related to multidrug resistance (ABCC1), tumor suppression (ATG5, CRYBG1, FOXO3, TP53, MGA), anti-apoptosis (BCL2, BCL2L1), immune checkpoints (CD274, CD47), and epigenetic regulation (DDX3X, EZH2, HDAC2/3) also were expressed at high levels. The molecular targeting agents eprenetapopt, tazemetostat, and vorinostat efficiently induced apoptosis in ENKL-J1 cells in vitro. Furthermore, GD2-directed chimeric antigen receptor T cells showed cytotoxicity against ENKL-J1 cells in vivo. These findings not only contribute to understanding the molecular and genomic characteristics of ENKL; they also suggest new treatment options for patients with advanced or relapsed ENKL.

Phase 2 Clinical Trial of Simultaneous Boost Intensity Modulated Radiation Therapy With 3 Dose Gradients in Patients With Stage I-II Nasal Type Natural Killer/T-Cell Lymphoma: Long-Term Outcomes of Survival and Quality of Life.

PURPOSE: The aim of this study was to investigate the treatment results and long-term quality of life in patients with early-stage extranodal natural killer/T-cell lymphoma who were prospectively treated with simultaneous boost intensity modulated radiation therapy (SIB-IMRT) with 3 dose gradients. METHODS AND MATERIALS: Sixty patients with stage I-II nasal cavity natural killer/T-cell lymphoma (NKTCL) and Waldeyer's ring NKTCL were enrolled in a single-arm, prospective, phase 2 clinical trial from August 2011 to April 2015. All patients were treated with definitive radiation therapy combined with short-course induction chemotherapy. A newly designed SIB-IMRT scheme was uniformly adopted, with 54.6 Gy for the gross tumor volume (GTV) of the primary tumor and GTV of the positive lymph nodes, 50.7 Gy for the high-risk clinical target volume (CTV), and 45.5 Gy for the low-risk CTV, all delivered in 26 daily fractions. Before SIB-IMRT, L-asparaginase-based induction chemotherapy was used in 95.0% (57/60) of patients. RESULTS: With a median follow-up time of 95.8 months, the 5-year locoregional recurrence-free survival, progression-free survival, and overall survival rates were 83.3%, 81.7%, and 88.3%, respectively. Dosimetric analysis in the first 21 patients showed satisfying conformality for planning target volume of GTV, high-risk CTV, and low-risk CTV, while the organs at risk were well protected. The results of long-term quality-of-life investigations in patients without progression were favorable, and nasal discomfort was the most common symptom. No grade 3 or 4 acute or late toxicities were observed. CONCLUSIONS: The scheme of target volume delineation and dose setting that we designed has favorable clinical effects with mild side effects in treating patients with stage I-II nasal cavity NKTCL and Waldeyer's ring NKTCL.

Histone methyltransferase KMT2D inhibits ENKTL carcinogenesis by epigenetically activating SGK1 and SOCS1.

BACKGROUND: Epigenetic alteration plays an essential role in the occurrence and development of extranodal natural killer/T cell lymphoma (ENKTL). Histone methyltransferase (HMT) KMT2D is an epigenetic regulator that plays different roles in different tumors, but its role and mechanism in ENKTL are still unclear. METHODS: We performed immunohistochemical staining of 112 ENKTL formalin-fixed paraffin-embedded (FFPE) samples. Then, we constructed KMT2D knockdown cell lines and conducted research on cell biological behavior. Finally, to further investigate KMT2D-mediated downstream genes, ChIP-seq and ChIP -qPCR was performed. RESULTS: The low expression of KMT2D was related to a decreased abundance in histone H3 lysine 4 mono- and trimethylation (H3K4me1/3). In KMT2D knockdown YT and NK-YS cells, cell proliferation was faster (P < 0.05), apoptosis was decreased (P < 0.05), the abundance of S phase cells was increased (P < 0.05), and the level of H3K4me1 was decreased. Notably, ChIP-seq revealed two crucial genes and pathways downregulated by KMT2D. CONCLUSIONS: KMT2D is a tumor suppressor gene that mediates H3K4me1 and influences ENKTL proliferation and apoptosis by regulating the cell cycle. Moreover, in ENKTL, serum- and glucocorticoid-inducible kinase-1 (SGK1) and suppressor of cytokine signaling-1 (SOCS1) are downstream genes of KMT2D.

Extranodal NK/T-Cell Lymphoma Predominantly Composed of Anaplastic Cells: A Frequently Misdiagnosed and Highly Aggressive Variant.

Extranodal NK/T-cell lymphoma (ENKTL) is a non-Hodgkin lymphoma associated with the Epstein-Barr virus that primarily affects individuals in East Asia and indigenous populations in Central and South America. Morphologically, ENKTL typically consists of medium-sized cells or a combination of small and large cells. This report presents 10 cases characterized by predominantly anaplastic cells with diffuse expression of CD30, resembling anaplastic lymphoma kinase-negative anaplastic large cell lymphoma (ALK-negative ALCL) and demonstrating highly aggressive behavior. The cohort included 9 males and 1 female, ranging in age from 29 to 65 years (median age: 47 y). Eight patients presented with nasal disease, while 2 had non-nasal disease. Five patients had stage I/II disease, and the remaining 5 had stage III/IV disease. Morphologically, necrosis was observed in 9 cases, angiocentric-angiodestructive growth in 3 cases, and pseudoepitheliomatous hyperplasia in 2 cases. Anaplastic cells predominated in all cases, with some displaying eccentric, horseshoe-shaped, or kidney-shaped nuclei (referred to as "Hallmark" cells). The morphology profile was monomorphic in 3 cases and polymorphic in 7 cases. Immunohistochemically, all cases tested positive for cytotoxic granule markers (TIA1 and granzymeB) and Epstein-Barr virus-encoded RNA. Cytoplasmic expression of CD3ε and CD56 was observed in 9 of 10 cases. Interestingly, most cases (7 of 8) exhibited variable expression of MuM1, ranging from 10% to 90%. All cases showed diffuse positivity for CD30 but were negative for ALK, resulting in 3 cases being initially misdiagnosed as ALK-negative ALCL. Compared with nonanaplastic cases, anaplastic cells predominant ENKTL had a significantly higher frequency of "B" symptoms, bone marrow involvement, hemophagocytic lymphohistiocytosis, and higher Ki67 proliferative index. These findings provide valuable information for pathologists, expanding their understanding of the cytologic spectrum of ENKTL. This rare variant of ENKTL, characterized by the predominance of anaplastic cells and diffuse CD30 expression, exhibits high aggressiveness and should be differentiated from ALK-negative ALCL. Awareness of this uncommon variant is crucial in preventing misdiagnosis and ensuring the timely initiation of therapy.

Comparative analysis of upper aerodigestive tract and non-upper aerodigestive tract in NK/T-cell lymphoma.

OBJECTIVE: Nasal or extranasal natural killer/T-cell lymphoma (NKTCL) is a very rare aggressive lymphoma, but it is increasingly diagnosed. To evaluate some specificity by comparative analysis between primary upper aerodigestive tract (UAT) and non-upper aerodigestive tract (NUAT)NKTCL. METHODS: A retrospective analysis was performed on NKTCL patients from January 2013 to November 2022 in our cancer center. RESULTS: The majority of the lesions were UAT-NKTCL 70 cases (92.1%), the primary NUAT occurred in 6 cases. Patients in the UAT group were mainly in the early stage and in the low and medium risk, while those in the NUAT group were late stage and in high risk (p = 0.000). The expressions of CD3 and TIA-1 in UAT group were higher than those in NUAT group (p = 0.031, p = 0.003), while CD7 was dominant in NUAT group (p = 0.009). For early stage NKTCL, multivariate analysis suggested that gender and PINK score were independent factors affecting PFS and OS (p < 0.05). The 3 year OS rate in initial CR group was 90.1% versus 46.4% in non-CR group (p = 0.000). In advanced stage, KI67% and bone marrow involvement were independent factors affecting OS (p = 0.022, p = 0.038). CONCLUSION: It was difficult to distinguish between UAT and NUAT-NKTCL from histopathology. NUAT-NKTCL patients did have advanced stage and poor outcome. The prognostic value of PINK score and bone marrow involvement was proposed. We aimed to improve initial CR rates, as well as to find new predictive models to predict the whole population.

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.

Appropriate timing to perform an interim 18F-FDG PET/CT in patients with nasal-type extranodal natural killer/T cell lymphoma.

Interim 18F-FDG PET/CT (I-PET) has a role in response evaluation and treatment guidance in patients with nasal-type extranodal natural killer/T cell lymphoma (ENKTL). However, there was no agreement on the timing of I-PET performed, after chemotherapy or after chemoradiotherapy. We aimed to find the appropriate timing for I-PET by assessing the prognostic value of I-PET in response evaluation in ENKTL patients. Two hundred and twenty-seven ENKTL patients who had undergone I-PET were retrospectively included. All patients were grouped based on their therapeutic strategy received, chemotherapy or chemoradiotherapy. The Deauville 5-point score (DS) was used to interpret the I-PET images. The hazard ratio (HR) and C-index were used to measure the discriminatory and prognostic capacities of I-PET performed at different times. One hundred and six patients underwent the I-PET after chemotherapy (chemotherapy group), while I-PET was performed after chemoradiotherapy in 121 patients (chemoradiotherapy group). Eighty-seven patients were classified as metabolic remission (DS score of 1-3), while the other 140 were classified as non-metabolic remission (DS score of 4-5) according to the Deauville criteria. There were no significant survival differences between patients in metabolic remission and in non-metabolic remission in either progression-free survival (PFS, p = 0.406) or overall survival (OS, p = 0.350). In the chemotherapy group, patients in metabolic remission had significantly superior PFS than patients in non-metabolic remission (p = 0.012). For OS, a discriminative trend was also found on the survival curve between patients in metabolic remission and in non-metabolic remission (p = 0.082). In the chemoradiotherapy group, there was no significant difference in PFS (P = 0.185) or OS (P = 0.627) between patients in metabolic remission and in non-metabolic remission. I-PET after chemotherapy yields higher discriminative power and has the ability for prognostic prediction in nasal-type ENKTL patients. I-PET after radiochemotherapy has no prognostic value. Thus, the appropriate timing for I-PET is after chemotherapy but before radiotherapy for response evaluation in nasal-type ENKTL patients.

Assessment of Bone Marrow Involvement in Extranodal NK/T-Cell Lymphoma: Positron Emission Tomography versus Bone Marrow Biopsy, and the Significance of Minimal Involvement by EBV+ Cells (KROG 18-09).

PURPOSE: This study aims to investigate the diagnostic significance of positron emission tomography/computed tomography (PET/CT) in assessing bone marrow (BM) involvement through a comparison of PET/CT findings with BM biopsy in extranodal natural killer/T-cell lymphoma. MATERIALS AND METHODS: The medical records of 193 patients were retrospectively reviewed. Patients were categorized as having early-stage (PET-ES) or advanced-stage (PET-AS) disease based on PET/CT results. The BM involvement was classified into three groups according to BM biopsy: gross BM involvement, minimal BM involvement (defined as the presence of a limited number of Epstein-Barr virus-positive cells in BM), and no involvement. Calculations of the accuracy of PET/CT in detecting BM involvement and analysis of the clinical outcomes (progression-free survival [PFS] and overall survival [OS]) according to the BM biopsy status were performed. RESULTS: PET/CT exhibited a sensitivity of 64.7% and a specificity of 96.0% in detecting gross BM involvement. For detecting any (both gross and minimal) BM involvement, the sensitivity was 30.4%, while the specificity was 99.0%. Only one patient (0.7%) demonstrated gross BM involvement among the PET-ES group. Survival outcomes of the PET-ES group with minimal BM involvement (3-year PFS, 55.6%; OS, 77.0%) were closer to those of the PET-ES group with no BM involvement (3-year PFS, 62.2%; OS, 80.6%) than to those of the PET-AS group (3-year PFS, 20.1%; OS, 29.9%). CONCLUSION: PET/CT exhibits high specificity, but moderate and low sensitivity in detecting gross and minimal BM involvement, respectively. The clinical significance of minimal BM involvement for patients in the PET-ES group may be limited.