NK cells

Natural Killer Cells

Misdiagnosis analysis: 120 patients with nasal extranodal NK/T cell lymphoma in head and neck.

Objective:The Clinicopathological characteristics and the reason of misdiagnosis about nasal extranodal NK/T cell lymphoma in head and neck(ENKTL) are analysised to raise awareness and reduce misdiagnosis. Method:One hundred and twenty patients with ENKTL, diagnosed pathologically in head and neck from May 2010 to April 2018, were analyzed retrospectively. All cases were divided into misdiagnosed group and non-misdiagnosed group according to whether there were misdiagnosis and mistreatment before diagnosis. The differences of clinicopathological characteristics between the two groups before and after diagnosis were compared. The differences of overall survival(OS) between the two groups after treatment were also compared. Result:The misdiagnosis rate of this study was 71.7%, and they were misdiagnosed as sinusitis, nasal polyps, upper respiratory tract infection and so on. On the whole, the 1-year OS, 3-year OS and 5-year OS were 77.8%, 65.9% and 49.3% respectively. There was no significant difference in sex, age, first symptom, initial site, B symptom, superficial lymph node enlargement and weight loss between two groups before diagnosis(P>0.05), however, there were significant differences in relative specific signs, hospital grade and time from first visit to definite diagnosis(P<0.05). The proportion of the high-level hospitals in the first visit hospital was significantly lower than that in the non-misdiagnosed group, while the time from the first visit to the final diagnosis was significantly longer than that in the non-misdiagnosed group. There was no significant difference in international prognostic index(IPI) score, expression of Ki-67, therapeutic schedule, chemotherapy regimen for patients receiving chemotherapy, and radiation dose for patients receiving radiotherapy after diagnosis between the two groups(P>0.05), but there was a significant difference in the clinical stages of Ann Arbor between the two groups(P<0.05). The clinical staging of the misdiagnosed group was later than that of the non-misdiagnosed group. The 1-year OS, 3-year OS and 5-year OS were 73.6%, 59.3% and 43.2% in the misdiagnosed group respectively, and 88.2%, 82.4% and 64.2% in the non-misdiagnosed group respectively. The overall survival rate in the misdiagnosis group was lower than that in the non-misdiagnosed group, and the overall survival time was lower than that in the non-misdiagnosed group. However, there was no significant difference in the overall survival rates between the early stage(Ⅰ and Ⅱ) and the advanced stage(Ⅲ and Ⅳ) of Ann Arbor(P>0.05). Conclusion:The non-specific clinical and the complexity of pathological features of ENKTL in head and neck might cause misdiagnosis, which leads to prolonged time from first visit to definite diagnosis, thus results in disease progression, and ultimately may lead to decreased overall survival rate. To avoid the misdiagnosis and early diagnosis is very important.

[Clinicopathologic analysis of extranodal non-hodgkin lymphoma of the sinonasal cavities: a 15-case report].

Objective:To investigate the clinical manifestation, imaging and histological features of different histological subtypes of non-Hodgkin’s lymphoma of nasal cavity and paranasal sinuses.Method:Fifteen NHL patients of the sinonasal region were collected from the Department of Otolaryngology of Peking University Third Hospital from 2010 to 2016. HE staining and immunohistochemical staining were performed. The clinical characteristics and imaging features of different subtypes were described and analyzed.Result::We analyzed a total of 6 patients with localized sinonasal diffuse large B cell lymphoma and 9 patients with localized sinonasal extranodal NK/T cell lymphoma. The age distribution for these two subtypes is very distinct. The median age of the patients with localized sinonasal extranodal NK/T cell lymphoma was 39 years. There were 5 males and 4 females. Nine sinonasal NHLs were NK/T-cell lymphoma, nasal type, all of which were infected with EBV. The median age of the patients with localized sinonasal diffuse large B cell lymphoma was 64 years. There were 3males and 3 females. Symptoms for patients with SN-DLBCL and SN-ENKTL were significantly different in epiphora, proptosis, diplopia and nasal congestion (P=0.18, 0.004, 0.18, 0.18). Imaging features for patients with SN-DLBCL and SN-ENKTL were significantly different in tumor extended to orbit and inferior turbinate (P>0.05). Positive staining for CD 56 was detected in 9 patients, for CD 3 in 9 patients, for EBER in 9 patients. The Hans algorithm identified 1 patient with the germinal center B-cell (GCB) subtype and 5 with the non-GCB subtype.Compared with the control group, the observation group was significantly better than the control group (P < 0.01).Conclusion:Early symptoms of epiphora, proptosis, diplopia, and images finding with orbital invasion should be highly suspected of diffuse large B cell lymphoma. Positive staining for CD 56 and EBER were detected in all patients with extranodal NK/T cell lymphoma, and positive staining for CD20 was detected in all patients with SN-DLBCL.

[Nasal NK/T-cell lymphoma: about two rare cases].

NK/T-cell lymphoma is a severe and rare disorder in Africa and in Europe. Treatment is based on radiotherapy and chemotherapy. We here report two cases of elderly patients aged 55 years and 52 years, respectively, with bilateral nasal obstruction associated with purulent rhinorrhea. Clinical examination showed cleft palate. Diagnosis was made on the basis of immunohistochemical examination of biopsies. Both patients underwent CHOEP chemotherapy followed by radiotherapy. Nasal NK/T-cell lymphoma is an aggressive type of non-Hodgkin’s lymphoma with specific clinicopathologic features. Combining chemotherapy with radiotherapy in patients with advanced stage of the disease does not seem to improve survival compared with radiotherapy alone, which is the treatment of choice especially for localized stages. Nasal NK/T-cell lymphoma is rare. Diagnosis is based on immunohistochemical examination. Treatment includes chemotherapy and radiotherapy. This lymphoma has a poor overall prognosis, even with appropriate therapy.

[Value of PET/CT in the prognosis of extranodal NK/T cell lymphoma].

Objective: To explore the value of Positron-Emission Tomography/Computed Tomography (PET/CT) in the prognosis of extranodal NK/T cell lymphoma. Methods: The patients of NK/T cell lymphoma diagnosed from January 2007 to July 2016 in Department of Pathology of Beijing Tongren Hospital were enrolled in this study. Seventy-two in-hospital patients were examined on the invasion of adjecent tissue or organ by PET/CT. The PET/CT results were analyzed retrospectively. Kaplan-Meier method was used to analyze the prognostic value of the positive results by PET/CT on overall survival (OS). Results: There were 54 males and 18 females with median age of 44.5 years (13-75 years). According to Ann Arbor staging system, there were 16 cases (22.2%) in stage Ⅰ, 29 cases (40.3%) in stage Ⅱ, 6 cases (8.3%) in stage Ⅲ and 21 cases (29.2%) in stage Ⅳ. According to the IPI scoring system, there were 34 cases (47.2%) in the low risk group (0-1 point), 21 cases (29.2%) in the low-middle risk group (2 points), 16 cases (22.2%) in the middle-high risk group (3 points), and 1 case (1.4%) in the high risk group (4-5 points) . The median follow-up time was 29.2 months (1-118 months). The disease occured in unilateral nasal cavity in 26 cases (36.1%), bilateral nasal cavities in 36 cases (50.0%), nasopharynx, oropharynx and pharynx in 10 cases (13.9%). The tumors of 51 cases involved the surrounding tissue, including nasal wings in 29 cases (40.3%), nasal sinus in 29 cases (40.3%), maxillofacial soft tissue in 18 cases (25.0%), orbital in 12 cases (16.7%), maxilla and skull base in 8 cases (11.1%), eyelid in 6 cases (8.3%), brain tissue in 3 cases (4.2%), eyeball in 2 cases (2.8%). In addition, cervical and inguinal lymphadenopathy were found in 54 cases (75.0%) . Splenomegaly and hepatomegaly were found in 10 cases (13.9%) and 2 cases (2.8%), respectively. Survival analysis showed that the clinical stage and IPI were significantly associated the clinical prognosis (P=0.000, 0.001, respectively). Involvement of the maxillofacial soft tissue, eyelid, orbital, maxilla and skull base and brain tissue were significantly related to reduced the overall survival time (P=0.006, 0.000, 0.024, 0.001 and 0.015, respectively). Involvement of palate or tonsil, the nosewingand nasal sinus did not show significant shorter overall survival (P=0.091, 0.063, and 0.139, respectively). Cox regression multivariate analysis showed maxilla and skull base involvement was independent adverse prognostic factor (P=0.047). Conclusions: The PET/CT examination can accurately detect the extent of adjacent and distant tissues of tumor involvement of NK/T cell lymphoma by showing the tumor structure and metabolic status, thus has important value in the clinical staging and prognosis predication.

[Analysis of Clinical Characteristics for Primary Adrenal Lymphoma].

To explore clinical characteristics of the Primary Adrenal Lymphoma(PAL), so as to enhance the understanding of diagnosis, treatment and prognosis of PAL.
The clinical data of 2 patients with PAL retrospectively analyzed and the clinical characteristics were explored in combination with releted literalures.
Adrenal gland neoplasm was found in 2 patients by imaging examination. The pathological type of one case was diffuse large B cell lymphoma, the other one was extranodal NK/T-cell lymphoma. The former refused to hosipitali3t and the other received to be admited in hospital after the definite diagnosis. She died at the 32th day after diagnosis, due to the complication with acute pancreatitis before chemotherapy. The latter accepted the scheme of”Gemox”combining with the scheme”VP-16+DXM”to control hemophagocytic lymphohistiocytosis. The patient’s condition deteriorated rapidly after a short period of improvement, then died at the 40th day after chemotherapy because of multiple organ failure.
PAL is a rare extra-nodal lymphoma with higher malignancy, the combination of chemotherapy and radiotherapy results in the best outcome among all the treatments. The prognosis of patients with different pathological types was diverse, thus it is very important to choose the appropriate treatment according to different pathological types.
Clinical characteristics of primary intestinal NK/T cell lymphoma, nasal type: Case series and review of the literature.

Primary intestinal NK/T cell lymphoma is rare but aggressive and exhibits a poor prognosis. Little is known about its clinical characteristics because few studies with small sample sizes have been reported.
To provide clinicopathological features and endoscopic findings and to summarize the treatment outcomes of primary intestinal NK/T cell lymphoma to improve our understanding of this disease.
Between January 2011 to December 2016, 13 patients with confirmed primary gastrointestinal NK/T cell lymphoma at our center were described, and an updated literature review was provided.
In this series of 13 cases, 69.23% were men, the median age was 39 years, and the median survival was 6 months. The common clinical manifestations included abdominal pain (76.92%) and gastrointestinal bleeding (46.15%). Lymphomas were common in the large intestine (69.23%). In 76.92% of patients, the clinical staging was stage I, and all 13 patients manifested ulcerative lesions and no tumor mass on endoscopy. The clinical characteristics of primary intestinal NK/T cell lymphomas were similar to results in existing literature.
Intestinal NK/T cell lymphoma shows nonspecific clinical features and poor prognosis, which is mainly expressed as ulcers on endoscopy. Emergency surgery may be an adverse prognostic factor of lymphoma, since it is prone to progress toward gastrointestinal perforation.
Successful full-dose DeVIC therapy in a patient with advanced-stage extranodal natural killer/T-cell lymphoma refractory to L-asparaginase.

Persistent peripheral blood EBV-DNA positive with high expression of PD-L1 and upregulation of CD4 + CD25 + T cell ratio in early stage NK/T cell lymphoma patients may predict worse outcome.

Although gemcitabine, oxaliplatin and L-asparaginase/pegylated asparaginase (P-GEMOX) treatment for early-stage extranodal natural killer/T cell lymphoma (ENKTL) is effective, some patients die within 1 year of diagnosis. We attempted to determine an optimal biomarker for identifying such patients. We enrolled 71 patients with ENKTL who received P-GEMOX between January 2011 and January 2014. We classified the patients according to the outcome into worse (died within 1 year) or better groups (survival time ≥ 3, 4 or 5 years). The area under the curve (AUC) was determined to identify the optimal biomarker for differentiating the groups. The AUC was highest in patients who were plasma Epstein-Barr virus (EBV) DNA-positive post-treatment. The AUC was 0.82, 0.86 and 0.86 when the worse group was compared to the better group, respectively. Among the post-treatment EBV DNA-positive patients, as compared to EBV DNA-negative patients, pre-treatment EBV DNA-positive patients had a higher proportion of CD4 + CD25 + T cells. There was higher programmed cell death protein ligand-1(PD-L1) expression in post-treatment EBV DNA-positive patients. Post-treatment positive EBV DNA status maybe a useful biomarker of worse outcomes in early stage ENKTL.
The optimal timing of radiotherapy in the combined modality therapy for limited-stage extranodal NK/T cell lymphoma (ENKTL): a systematic review and meta-analysis.

The optimal timing and sequencing of radiotherapy (RT) and chemotherapy (CT) in the treatment of limited-stage extranodal NK/T cell lymphoma (LS-ENKTL) has not been elucidated. The aim of this meta-analysis was to evaluate whether the timing of RT in relation to CT affects the survival of patients with LS-ENKTL. We searched Medline, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Clinicaltrials.gov , and relevant meeting abstract databases from inception through April 2018 without age or language restrictions. Studies comparing upfront RT plus CT with induction CT followed by RT in patients with LS-ENTKL were eligible for inclusion. Seven studies with 1593 patients were included, and all were retrospective cohort studies. Compared with induction CT followed by RT, upfront RT significantly improved OS of patients with LS-ENTKL (HR = 0.70, 95%CI 0.55-0.88, P = 0.002), with no evidence of heterogeneity across studies (I2 = 0%). In subgroup analyses, the beneficial effect of upfront RT on survival did not differ significantly between subgroups of studies with different types of chemotherapy regimens (anthracycline-based or non-anthracycline-based), the administration of concurrent chemoradiotherapy or not, and different median doses of RT (≥ 45 or < 45 Gy). These results suggest that upfront RT plus CT confers survival advantage over induction CT followed by RT for the treatment of LS-ENTKL, and this survival advantage is not significantly affected by the types of CT regimens or timing of CT. Given the retrospective nature of included studies, these results should be interpreted with caution in clinical practice.

Breakthrough Candida guilliermondii (Meyerozyma guilliermondii) fungemia after cord blood transplantation for extranodal NK-cell lymphoma with azole prophylaxis.

Fluconazole (FLCZ) is an azole antifungal agent and it has shown excellent clinical activities in suppressing fungemia with Candida albicans after hematopoietic stem cell transplantation. Increased administration of prophylactic FLCZ seems to have given rise to the relatively higher incidence of more resistant Candida non-albicans infection. We present a case with a rare breakthrough fungemia with C. guilliermondii after cord blood transplantation for Extranodal NK cell Lymphoma, nasal type (ENKL), during antifungal prophylaxis with FLCZ. High level of caution is needed for the breakthrough, especially after long-term azole administration.

Distribution of lymphoid neoplasms in Northwest China: Analysis of 3244 cases according to WHO classification in a single institution.

To explore the distribution of lymphoid neoplasms in Northwest China, the clinical and pathological data of lymphoma patients from 2006 to 2014 were analyzed according to the WHO classification in Xijing Hospital. Of the 3244 cases, mature B-cell neoplasms occupied 60.7%, while mature T/NK-cell neoplasms and Hodgkin’s lymphomas (HL) occupied 26.2% and 8.1%, respectively. The most common subtype of lymphoma was diffuse large B-cell lymphoma (35.0%), followed by extranodal NK/T-cell lymphoma, nasal type (ENKTCL) (12.9%) and marginal zone B-cell lymphoma (7.8%). Mixed cellularity (34.0%) was the most common subtype of HL. The especially high proportion of ENKTCL was the most outstanding feature of our study in comparison to previous reports. The mean age of all lymphoid neoplasms cases was 51years and most subtypes showed male predominance, with an average male-female ratio of 1.6. Extranodal lymphomas took up about 60% of all cases and gastrointestinal tract was the most frequently involved site. In conclusion, the distribution of lymphoid neoplasms of Northwest China showed some features similar to previous reports of China and other countries, but some subtypes presented distinct features.
Extranodal NK/T-cell lymphoma of the nasal cavity developed in a patient with intestinal Epstein-Barr virus-positive T/NK-cell lymphoproliferative disorder.

Extranodal NK/T cell lymphoma, nasal type (ENKL) developed in a patient with intestinal Epstein-Barr virus (EBV)-positive T/NK-cell lymphoproliferative disorder (LPD). The patient was a 46-year-old Chinese man who complained of diarrhea and abdominal pain without immune-deficiency. Endoscopy demonstrated ileum ulcers like Crohn’s disease, without histological granulomas. His symptoms continued waxing and waning for 3 years until he developed overt lymphoma (ENKL) in the nasal cavity. The ileum lesions exacerbated into a large deep ulcer, and the biopsy specimens from the ileum, including the one 3 years ago, showed infiltration of small lymphocytes containing many EBV-positive T/NK cells without atypia. Thus, the patient illness of intestine was revealed as intestinal EBV-positive T/NK-cell LPD, which might be closely associated with development of ENKL in this patient. In cases of inflammatory bowel disease without typical clinical courses and histological findings, check-up of EBV in the biopsy might help correct diagnosis.

The Genomics and Molecular Biology of Natural Killer/T-Cell Lymphoma: Opportunities for Translation.

Extranodal NK/T-cell lymphoma, nasal type (ENKTL), is an aggressive malignancy with a poor prognosis. While the introduction of L-asparaginase in the treatment of this disease has significantly improved the prognosis, the outcome of patients relapsing after asparaginase-based chemotherapy, which occurs in up to 50% of patients with disseminated disease, remains dismal. There is hence an urgent need for effective targeted therapy especially in the relapsed/refractory setting. Gene expression profiling studies have provided new perspectives on the molecular biology, ontogeny and classification of ENKTL and further identified dysregulated signaling pathways such as Janus associated kinase (/Signal Transducer and activation of transcription (JAK/STAT), Platelet derived growth factor (PDGF), Aurora Kinase and NF-κB, which are under evaluation as therapeutic targets. Copy number analyses have highlighted potential tumor suppressor genes such as PR Domain Zinc Finger Protein 1 (PRDM1) and protein tyrosine phosphatase kappa (PTPRK) while next generation sequencing studies have identified recurrently mutated genes in pro-survival and anti-apoptotic pathways. The discovery of epigenetic dysregulation and aberrant microRNA activity has broadened our understanding of the biology of ENKTL. Importantly, immunotherapy via Programmed Cell Death -1 (PD-1) and Programmed Cell Death Ligand1 (PD-L1) checkpoint signaling inhibition is emerging as an attractive therapeutic strategy in ENKTL. Herein, we present an overview of the molecular biology and genomic landscape of ENKTL with a focus on the most promising translational opportunities.

Recurrence of Extranodal Natural Killer/T-cell Lymphoma Presenting as Tarsal Tunnel Syndrome.

This case report is a rare form of lymphoma recurrence which presented as tarsal tunnel syndrome. The patient had been previously treated for the malignancy and was presumed to be in remission; however, standard radiology imaging protocols failed to include the distal extremities on these scans. The patient presented to the orthopedic clinic with tarsal tunnel symptoms and a mass in the tarsal tunnel. A complete evaluation resulted in a diagnosis of recurrence of the malignancy. This case illustrates the importance of a thorough medical history and personal review of imaging studies, and how a systematic approach can produce the correct diagnosis for any unknown lesion. Furthermore, this case may prompt oncologists to consider obtaining whole-body fluorodeoxyglucose positron emission tomography computed tomography when evaluating for recurrence in patients.

[Extranodal NK/T-cell lymphoma, nasal type: a clinical analysis].

Objective:To explore the clinical diagnosis and treatment characteristics and clinical factors of extranodal NK/T-cell lymphoma, nasal type and provide the basis for clinical individual therapy and experience.Method:The 25 cases personal data of ENKTL received from December in 2009 to July in 2016 by our department including clinical manifestation, the serum EBV-DNA detection, imaging examination, Ann-Arbor staging, histological grade, treatment, and prognosis, etc. were retrospectively analyzed. All of the patients were pathological diagnosis and received standard, specification and system treatment. Single factor survival analysis was performed by Kaplan-Meier method and Log-rank test, and multivariate analysis was carried out using Coxproportional hazard model in the risk assessment about the factors affecting the prognosis of clinical.Result:Of the 25 patients, 15 cases(60%) were in stage ⅠE-ⅡE, which 1 year and 3 years (overall survival) OS were 100%, 100% respectively and 10 cases(40%) were in stage ⅢE-ⅣE, which 1 year and 3 years OS were respectively 40.0%, 26.7%. It had significant statistical difference (P= 0.000). Radiotherapy alone in 3 cases which 1 year and 3 years OS were respectively 100%, 100%;Chemotherapy alone in 6 cases, which 1 year and 3 years OS were 53.6% and 53.6%, respectively; 16 cases of comprehensive treatment combined radiation and chemotherapy which 1 year and 3 years OS are 84.6% and 84.6% respectively. There were significant difference between three kinds of treatment model (P= 0.027), and chemotherapy alone had the worst prognosis. Further multivariate analysis using Coxproportional hazard model showed that the course of the disease, B symptoms, EBV-DNA copy number positive, treatment mode closely associated with the prognosis (P were 0.006, 0.003, 0.010, 0.040 respectively).Conclusion:Extranodal NK/T-cell lymphoma, nasal type invasive is strong, the overall prognosis is poor. For early Ann Arbor staging, low risk and limited to the nasal cavity cases, radiotherapy alone curative effect is better. While for strong attack range or terminal patients, chemotherapy combined with radiotherapy is the first selection. In addition, this result shows that Ann Arbor staging, treatment pattern, the course of the disease, B symptoms, EBV-DNA copy number positive are independent prognostic factors.

Short-Course Versus Long-Course Chemoradiotherapy for Stage IE-IIE Extranodal Natural Killer/T cell Lymphoma, Nasal Type: A Multicenter Retrospective Study.

BACKGROUND This study compared clinical outcomes and adverse events between L-asparaginase/pegaspargase-based short-course and long-course chemoradiotherapy in newly diagnosed stage IE-IIE extranodal natural killer/T cell lymphoma, nasal type (ENKTL). MATERIAL AND METHODS Patients were categorized into a short-course (2-4 chemotherapy cycles, median: 4, n=153) and long-course group (5-6 cycles, median: 6, n=83). The chemotherapy regimens included GELOX, SMILE, and VLP. The radiotherapy dose was 40-63 Gy (median: 55 Gy). Adverse events, treatment responses, and survival outcomes between the 2 groups were compared. RESULTS Ann Arbor stage IIE and short-course chemotherapy adversely affected overall survival (OS). Ann Arbor stage IE favorably affected progression-free survival (PFS). Grade 3-4 hematological toxicities were higher in the long-course group (25.3% vs. 14.4%, p=0.038). Ann Arbor stage was the single different clinical feature between the 2 groups, and independently affected survival outcomes. In subgroup analysis of stage IE, there was no difference in response rates and survival outcomes between the 2 groups. In subgroup analysis of stage IIE, the recurrence and death rates were significantly lower in the long-course group (6.1% vs. 23.2%, p=0.015; 12.2% vs. 39.3%, p=0.002; respectively), and the 3-year OS and PFS rates were much longer in the long-course group (87.8% vs. 62.5%, p<0.001; 83.7% vs. 57.1%, p=0.001; respectively). CONCLUSIONS When radiotherapy was combined with L-asparaginase/pegaspargase-based chemotherapy to treat early-stage ENKTL patients, 2-4 cycles of chemotherapy might be sufficient for stage IE patients, while stage IIE patients might require 5+ cycles.

Extranodal natural killer/T-cell lymphoma, nasal type, in Senegal.

The distribution of extranodal NK/T-cell lymphoma (ENKTCL) is highly inhomogeneous throughout the world. In Sub-Saharan Africa, despite the precocity of Epstein-Barr virus (EBV) infection and its endemicity, ENKTCL remains exceptionally reported. The purpose of this study was to report the epidemiological, clinical, paraclinical, and evolutionary characteristics of ENKTCL at the Aristide LeDantec University Hospital in Dakar, Senegal.
A 5-year retrospective review of all patients with histopathological, immunohistochemical, and in situ hybridization proven cutaneous lymphomas RESULTS: We collected seven cases corresponding to a frequency of 1.4 cases per year. ENKTCL accounted for 10.5% of all cutaneous lymphomas, ranking second after T-cell lymphomas. Men were predominantly affected (M : F ratio of 6), and the mean age was 38.5 years ± 4.06. The mean time before consultation was 7.3 months. The lymphomas affected primarily the nasal cavity in five cases and the skin in two cases. At admission, six patients had nasal mucosa involvement, which was isolated in three cases, associated with cutaneous lesions in three cases and lymph node involvement in three cases. CD56 was positive in only one case, and Eber transcribed RNA of EBV was expressed by in situ hybridization in all patients.
To our knowledge, we have reported the first and largest series of ENKTCL in Sub-Saharan Africa. Our study shows an intermediate prevalence between that reported from Asia, Latin America, and the West. It was also noted a young age of patients, a prolonged diagnostic delay, a frequent negativity of CD56 marker, and a very poor prognosis of the disease in our region.

Late diagnosis: a case of rapidly progressive extranodal NK/T cell lymphoma, nasal type.

Extranodal natural killer (NK)/T cell lymphoma, nasal type is a condition that has poor prognosis. Accurate diagnosis of lymphoma is made by pathological findings. We report a case of extranodal NK/T cell lymphoma, nasal type affecting the lung and liver and which was difficult to diagnose because of negative biopsy results from multiple sites. A 39-year-old man who had dry cough and fever for 1 month was referred to our hospital. He had pancytopenia and elevated serum levels of lactate dehydrogenase and soluble interleukin-2 receptor. Hepatosplenomegaly and multiple lung nodules were found on imaging study. Specimens of bronchoscopic lung, percutaneous liver, bone marrow and random skin biopsies were all negative. Open lung biopsy was not definitive. Unfortunately, disease progression was rapid and fatal before results of pleural fluid cytology and a second liver biopsy showed extranodal NK/T cell lymphoma, nasal type. This report focused on diagnostic planning for rapidly progressive extranodal NK/T-cell lymphoma, nasal type.