Intestinal T-cell and NK/T-cell lymphomas: A clinicopathological study of 27 Chinese patients

Monomorphic epitheliotropic intestinal T-cell lymphoma with obstructive pattern: A rare case of small bowel lymphoma

INTRODUCTION

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a very rare and aggressive type of gastrointestinal non-Hodgkin's lymphoma (NHL) with a poor prognosis.

CASE PRESENTATION

A 59-year-old man presented with a three-days history of diffuse abdominal pain associated with distention and obstipation. Abdominal computed tomography (CT) scan showed small bowel obstruction (SBO) due to moderately thickened jejunal loop. The SBO was treated conservatively, and after a workup, the patient underwent a laparoscopic oncological small bowel resection. The final pathology sampling revealed transmural sheets of atypical lymphoid cells that were identified as MEITL, which is a very rare type of small bowel lymphoma, by the histo-immunopathoplogy studies. He responded to three courses of chemotherapy, and the patient went into remission at the end of the third chemotherapy session. Five months post remission patient was rushed to the emergency with acute mesenteric ischemia and died shortly after.

DISCUSSION

An extremely uncommon and aggressive type of T-cell lymphoma is called monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL). Gastrointestinal involvement was detected in the majority of the patients. 40 % of the published cases had stage IV disease. Based on morphological classification, the tumors were classified into two groups: Typical (58 %) and atypical (i.e., non-monomorphic or exhibiting necrosis, angiotropism, or starry-sky pattern) (42 %). Mostly caused by driver gene changes that de-regulate JAK/STAT signaling and histone methylation, it is resistant to standard therapy and includes morphologic and genetic variants that carry a very high clinical risk.

CONCLUSION

We report a case of MEITL detected after jejunal resection in a patient presented initially with SBO. Our patient has a recurrence-free survival of 5 months after chemotherapy, but passed away 5 months after remission due to acute mesenteric ischemia.

Intestinal T-cell lymphoma not otherwise specified: a case report and literature review

Intestinal T-cell lymphoma, not otherwise specified (ITCL, NOS), primarily affects the small bowel but can involve the stomach and large bowel. This report presents an uncommon case of ITCL, NOS in a patient affecting the large bowel, supported by a literature review. An 87-year-old female presented with abdominal pain, fever, vomiting and weight loss. Imaging revealed nodular thickening of the transverse and right colon, confirmed as polypoid mass lesions with ulceration through colonoscopy and biopsy, indicating ITCL, NOS. CT scan showed adrenal nodes classifying it as stage VI. The patient was referred for palliative care and passed away 40 days later, likely due to tumor progression. This case underscores the rarity of large bowel ITCL, NOS and the diagnosis challenge.

Clinical characteristics, treatment, and survival of 30 patients with gastrointestinal natural killer/T-cell lymphoma

BACKGROUND

The gastrointestinal (GI) tract is the second most frequent extranasal involvement site for ENKTL. This study aimed to explore the clinicopathological features, treatment models, survival outcomes, and prognosis of gastrointestinal ENKTL (GI-ENKTL).

METHODS

The clinical data of GI-ENKTL patients were extracted from the China Lymphoma Collaborative Group (CLCG) database and were analyzed retrospectively.

RESULTS

A total of 30 patients were enrolled, with a male/female ratio of 4:1 and a median age of 42 years. Twenty-nine patients received chemotherapy, of whom 15 patients received asparaginase-based (ASP-based) regimens. Moreover, seven received surgery and three received radiotherapy. The overall response an d complete remission rates were 50.0% and 30.0% for the whole cohort, 50.0% and 37.5% for patients treated with ASP-based regimens, and 50.0% and 25.0% for those treated with non-ASP-based regimens, respectively. The median follow-up was 12.9 months and the 1-year overall survival rate was 40.0% for the whole cohort. For those patients in an early stage, ASP-based regimens resulted in a superior 1-year progression-free survival rate compared to non-ASP-based regimens (100.0% vs. 36.0%, p = .07). However, ASP-based regimens did not improve survival in patients at an advanced stage.

CONCLUSION

GI-ENKTL still has a poor prognosis, even in the era of modern asparaginase-based treatment strategies.

Clinical, endoscopic and pathological characteristics of primary gastrointestinal T-cell and NK/T-cell lymphomas

BACKGROUND AND AIMS

Gastrointestinal T-cell and NK/T-cell lymphomas are relatively rare and may be difficult to diagnose. Therefore, we performed a retrospective study of the clinical, endoscopic and pathological characteristics of these lymphomas, to provide additional data on this issue.

METHODS

From April 2013 to April 2021, consecutive patients diagnosed with primary gastrointestinal T-cell and NK/T-cell lymphomas were retrospectively reviewed. Their medical histories, laboratory, imaging, endoscopic, and pathology results were analyzed.

RESULTS

Forty-two patients were finally chosen, among whom, 24 patients had ENKTCL, 9 patients had MEITL, 2 patients had ALCL, ALK-, 1 patient had ALCL, ALK+, and 6 patients had PTCL, NOS. The median age of all the patients was 48 years old, and 73.81% (31 patients) were male. The patients' symptoms were abdominal pain, diarrhea, gastrointestinal bleeding, weight loss, fever, and others. The endoscopic results of 26 patients could be traced, and 69.23% of the patients showed multiple lesions. Ulcerative and ulceroinfiltrative lesions were common. Among the pathologic findings, necrosis, ulceration, and crypt atrophy were commonly found while epitheliotropism was relatively less common. Twelve patients (28.57%) had a history of misdiagnosis. After a median follow-up time of 26.9 months, 26 patients (66.70%) died of the disease. The median overall survival time was 8 months.

CONCLUSIONS

These lymphomas had nonspecific clinical manifestations, various endoscopic features, and were likely to be misdiagnosed as other diseases. The prognosis is still poor, and more in-depth research is needed to develop more precise treatments.

Intestinal natural killer/T-cell lymphoma presenting as a pancreatic head space-occupying lesion: A case report

BACKGROUND

Intestinal natural killer/T-cell lymphoma (NKTCL) is a rare and aggressive non-Hodgkin’s lymphoma, and its occurrence is closely related to Epstein-Barr virus infection. In addition, the clinical symptoms of NKTCL are not obvious, and the specific pathogenesis is still uncertain. While NKTCL may occur in any segment of the intestinal tract, its distinct location in the periampullary region, which leads clinicians to consider mimics of a pancreatic head mass, should also be addressed. Therefore, there remain huge challenges in the diagnosis and treatment of intestinal NKTCL.

CASE SUMMARY

In this case, we introduce a male who presented to the clinic with edema of both lower limbs, accompanied by diarrhea, and abdominal pain. Endoscopic ultrasound (EUS) showed well-defined homogeneous hypoechoic lesions with abundant blood flow signals and compression signs in the head of the pancreas. Under the guidance of EUS- fine needle biopsy (FNB) with 19 gauge or 22 gauge needles, combined with multicolor flow cytometry immunophenotyping (MFCI) helped us diagnose NKTCL. During treatments, the patient was prescribed the steroid (dexamethasone), methotrexate, ifosfamide, L-asparaginase, and etoposide chemotherapy regimen. Unfortunately, he died of leukopenia and severe septic shock in a local hospital.

CONCLUSION

Clinicians should enhance their understanding of NKTCL. Some key factors, including EUS characteristics, the right choice of FNB needle, and combination with MFCI, are crucial for improving the diagnostic rate and reducing the misdiagnosis rate.

Classification and challenges in the histopathological diagnosis of peripheral T-cell lymphomas, emphasis on the WHO-HAEM5 updates

Mature T-cell lymphomas represent neoplastic expansions of T-cell lymphocytes with a post-thymic derivation. Most of these tumors feature aggressive clinical behavior and challenging histopathological diagnosis and classification. Novel findings in the genomic landscape of T-cell lymphomas are helping to improve the understanding of the biology and the molecular mechanisms that underly its clinical behavior. The most recent WHO-HAEM5 classification of hematolymphoid tumors introduced novel molecular and histopathological findings that will aid in the diagnostic classification of this group of neoplasms. The current review article summarizes the most relevant diagnostic features of peripheral T-cell lymphomas with an emphasis on the updates that are incorporated at the WHO-HAEM5.

Surface CD3-negative monomorphic epitheliotropic intestinal T-cell lymphoma

Intestinal T/NK-cell lymphomas include enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), indolent T-cell lymphoproliferative disorders of the GI tract (ITCLPD), extranodal NK/T-cell lymphoma, nasal type (ENKTL), and intestinal T-cell lymphoma NOS (ITCL-NOS). Here we describe a case of surface CD3-negative MEITL. A 63-year-old Japanese female had a tumor located in the conglomerated ileum, which formed multiple mass lesions. The resected tissue showed a diffuse infiltration of monomorphic medium-sized lymphocytes with epitheliotropism. Flowcytometry using a fresh specimen of the tumor revealed positivity for CD7, CD8, CD38, and CD56, but not surface CD3. On immunohistochemistry, the tumor showed positivity for cytoplasmic CD3, CD8, CD56, TIA-1, Granzyme B, and perforin. EBER with in situ hybridization was negative. Moreover, H3K36me3, which is negative in MEITL with SETD2-mutation, was positive. This is an important case of MEITL due to its oncogenesis.

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.

T-Cell Non-Hodgkin Lymphoma of the Ileum Presenting as Perforation and Peritonitis: A Case Report

Background

Non-Hodgkin lymphoma (NHL) of the ileum, presenting as perforation and peritonitis, is a rare disease, derived from intestinal intraepithelial T lymphocytes. The degree of malignancy is extremely high. The pathogenesis of ileal perforation caused by NHL remains unclear, as well as the chromosome and immune system abnormalities, which may be related to NHL, and are indistinguishable from other benign and malignant conditions and are clinically nonspecific.

Case Report

We describe an 84-year-old man with abdominal pain for 4 days, which was aggravated for 3 h. The pain was in the upper abdominal region and was initially considered to be due to gastrointestinal perforation. He had persistent insidious pain, accompanied by nausea, vomiting, and fever. Physical examination indicated that the patient had pain all over the abdomen; also, rebound pain and muscle tension, and bowel sounds were reduced on auscultation. An abdominal CT scan showed free gas in the abdominal cavity. The patient was diagnosed with peritonitis due to hollow viscus perforation. A prompt exploratory laparotomy was performed. Intraoperative findings showed perforations in the ileum that are approximately 40 cm from the ileocecal region, which were 3–8 mm in size. A segmental distribution was observed, and the intestinal contents overflowed with purulent discharge around the perforation surface. Resection and ileostomy were performed, and the clinical histopathological examination confirmed T-cell lymphoma. The patient was advised to visit the Oncology Department for further chemotherapy.

Conclusion

Timely emergency surgery is the key to the treatment of ileal perforation caused by T-cell lymphoma. Resection and ileostomy were performed as intervention measures, and subsequent histopathological examination manifested T-cell lymphoma.

Intestinal T-cell lymphoma: A rare entity presenting with severe acute upper quadrant pain

Primary gastrointestinal T-cell lymphomas are rare. Presenting symptoms can be non-specific, and imaging studies can show overlap with nonmalignant processes. Definitive diagnosis requires clinical suspicion and histologic evaluation with ancillary studies for appropriate disease classification and therapeutic intervention.

Primary Gastrointestinal T-Cell Lymphoma and Indolent Lymphoproliferative Disorders: Practical Diagnostic and Treatment Approaches

Simple Summary

It is challenging for pathologists to diagnose primary gastrointestinal T-cell neoplasms. Besides the rarity of the diseases, the small biopsy material makes it more difficult to differentiate between non-neoplastic inflammation and secondary involvement of extra gastrointestinal lymphoma. Since this group of diseases ranges from aggressive ones with a very poor prognosis to indolent ones that require caution to avoid overtreatment, the impact of the diagnosis on the patient is enormous. Although early treatment of aggressive lymphoma is essential, the treatment strategy is not well established, which is a problem for clinicians. This review provides a cross-sectional comparison of histological findings. Unlike previous reviews, we summarized up-to-date clinically relevant information including the treatment strategies as well as practical differential diagnosis based on thorough literature review.

Abstract

Primary gastrointestinal (GI) T-cell neoplasms are extremely rare heterogeneous disease entities with distinct clinicopathologic features. Given the different prognoses of various disease subtypes, clinicians and pathologists must be aware of the key characteristics of these neoplasms, despite their rarity. The two most common aggressive primary GI T-cell lymphomas are enteropathy-associated T-cell lymphoma and monomorphic epitheliotropic intestinal T-cell lymphoma. In addition, extranodal natural killer (NK)/T-cell lymphoma of the nasal type and anaplastic large cell lymphoma may also occur in the GI tract or involve it secondarily. In the revised 4th World Health Organization classification, indolent T-cell lymphoproliferative disorder of the GI tract has been incorporated as a provisional entity. In this review, we summarize up-to-date clinicopathological features of these disease entities, including the molecular characteristics of primary GI T-cell lymphomas and indolent lymphoproliferative disorders. We focus on the latest treatment approaches, which have not been summarized in existing reviews. Further, we provide a comprehensive review of available literature to address the following questions: How can pathologists discriminate subtypes with different clinical prognoses? How can primary GI neoplasms be distinguished from secondary involvement? How can these neoplasms be distinguished from non-specific inflammatory changes at an early stage?

Clinicopathologic Features of Peripheral T-Cell Lymphoma in Sub-Saharan Africa

OBJECTIVES

Peripheral T-cell lymphomas (PTCLs) are heterogeneous, clinically aggressive, and rare. Subtype distribution varies by geographic location; however, data from sub-Saharan Africa (SSA) are lacking. We sought to elucidate clinicopathologic features of PTCL in SSA.

METHODS

We reviewed PTCL consultation cases from three SSA countries. PTCL subtype was determined per 2017 World Health Organization classification. Cases with sufficient material were evaluated by polymerase chain reaction for human T-cell leukemia virus type 1 (HTLV-1) and T-cell receptor γ (TCRG) rearrangement.

RESULTS

Among 32 cases, median age was 45 years and male-to-female ratio was 1.7. Thirty (94%) of 32 cases required additional workup for subclassification. PTCL, not otherwise specified (PTCL-NOS) was the most common subtype (13/32, 41%), followed by PTCL with T-follicular helper phenotype (6/32, 19%) and systemic anaplastic large cell lymphoma (6/32, 19%). Four (16%) of 25 cases were Epstein-Barr virus positive (EBV+) (2/2 extranodal natural killer/T-cell lymphoma, 1/13 PTCL-NOS, and 1/4 angioimmunoblastic T-cell lymphoma with EBV+ immunoblasts). Two (15%) of 13 patients with PTCL-NOS were human immunodeficiency virus positive. No cases with evaluable DNA (0/15) were HTLV-1 positive, and 9 of 10 showed clonal TCRG rearrangements.

CONCLUSIONS

In comparison to Western studies, PTCLs from SSA show similar subtype distribution and male predominance but a younger age at diagnosis. Appropriate diagnosis of PTCL requires extensive ancillary testing not readily available in low-income countries, including much of SSA.

Primary Gastrointestinal T/NK Cell Lymphoma

Primary gastrointestinal T/NK cell lymphoma (GI-TNKL) is an uncommon and heterogeneous group of lymphoid malignancies. We aimed to investigate their subtype distribution, clinicopathologic characteristics, and clinical outcomes. A total of 38 GI-TNKL cases and their clinical and pathological characteristics were analyzed. GI-TNKL occurred in adults with a median patient age in the sixth decade of life and showed a slight male predominance. The most common histologic type was extranodal NK/T-cell lymphoma, nasal type (ENKTL; 34.2%), followed by monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL; 31.6%), intestinal T-cell lymphoma, NOS (ITCL, NOS, 18.4%), anaplastic large cell lymphoma, ALK-negative (ALCL, ALK-; 13.2%). The small intestine was the primary affected region. More than 90% of patients complained of various GI symptoms and cases with advanced Lugano stage, high IPI score, or bowel perforation that required emergent operation were not uncommon. GI-TNKL also showed aggressive behavior with short progression-free survival and overall survival. This thorough clinical and pathological descriptive analysis will be helpful for accurate understanding, diagnosis, and treatment.

Diagnostic approach to T- and NK-cell lymphoproliferative disorders in the gastrointestinal tract

Most gastrointestinal NK and T cell lymphomas are aggressive in behavior, although in recent years a subset of indolent lymphoproliferative disorders have been described, which must be distinguished from their more malignant mimics. Intestinal T-cell lymphomas may arise from intra-epithelial lymphocytes and display epitheliotropism, such as enteropathy-associated T-cell lymphoma and monomorphic epitheliotropic intestinal T-cell lymphoma. They are both aggressive in behavior but differ in their clinic-pathological features. On the other hand, intra-epithelial lymphocytes are not prominent in intestinal T-cell lymphoma, NOS, which is a diagnosis of exclusion and probably represents a heterogeneous group of entities. Indolent lymphoproliferative disorders of NK- and T-cells of both CD8 and CD4 subsets share a chronic, recurring clinical course but display differences from each other. CD8+ T-cell lymphoproliferative disorder of GI tract has a low proliferative fraction and does not progress nor undergo large cell transformation. Whilst NK-cell enteropathy runs an indolent clinical course, it may display a high proliferation fraction. On the other hand, CD4+ indolent T-cell lymphoproliferative disorder displays variable proliferation rates and may progress or transform after a number of years. In Asia and South America, it is not uncommon to see involvement of the gastrointestinal tract by EBV-associated extranodal NK/T cell lymphoma, nasal type, which must be distinguished from NK cell enteropathy and EBV-associated mucocutaneous ulcers.

Case Report: Primary NK/T Cell Lymphoma Nasal Type of the Colon With Multiple Intestinal Perforations

Background: Extranodal NK/T cell lymphoma is a rare non-Hodgkin lymphoma mainly involving the upper aerodigestive tract, even rarer is primary extranasal disease involving the intestine. We present a case of primary intestinal NK/T cell lymphoma with diagnostic challenge, which eventually developed into multiple intestinal perforations.

Case Presentation: A 35-year-old man presented with diarrhea and recurrent fever. Abdominal CT revealed multi-segmental intestinal wall thickening. Colonoscopy showed multiple irregular ulcers in colon. During the hospitalization, the patient developed intestinal perforation and an emergency surgery was performed. The resected specimen showed multiple perforations of the colon. The surgical samples underwent pathological analysis, and a diagnosis of extranodal NK/T cell lymphoma nasal type was confirmed. After recovering from surgery, the patient started receiving chemotherapy and PD-1 monoclonal antibody. Fortunately, he was discharged after significant improvement in his general condition. Eleven months follow-up was uneventful.

Conclusion: Early diagnosis of primary intestinal NK/T cell lymphoma is frequently difficult. Most patients were definitely diagnosed only after surgical resection following complications, resulting in a poor prognosis. Therefore, doctors should maintain high suspicion of this malignancy for early diagnosis at an early stage clinically.

Various Endoscopic Features in Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma

A 77-year-old female who had an acute severe abdominal pain was taken to the emergency room in the previous hospital. CT scans showed jejunum and ileum wall thickening and fatty deposits around the small intestinal tract, and gastrointestinal perforation could not be ruled out. By using single anal and oral balloon endoscopy, we observed mild edema with petechial erythema, shallow erosions with edematous mucosa and ulcers with surrounded disrupted villous structures at the jejunum and ileum. Histological analysis revealed atypical lymphocytes infiltrating the small intestinal mucosa demonstrating intraepithelial lymphocytosis. Immunohistochemical staining revealed that CD3, CD7, and CD56 staining was positive, and CD4, CD5, and CD8 staining was negative in infiltrated lymphocytes. We made the diagnosis of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) with the combination of HE staining and IHC. PET-CT showed abnormal uptake in irregular wall thickening of the small intestine, lymph nodes, ribs, spine and pelvic bone. She was treated with chemotherapy (etoposide, prednisolone, oncovin, cyclophosphamide, hydroxydaunorubicin) and is still alive 1 year after the diagnosis. We reported the various endoscopic findings in the same MEITL patient by using single balloon endoscopy. We also summarized endoscopic characteristics of MEITL patients.

[Clinical characteristics and survival analysis of primary intestinal extranodal NK/T-cell lymphoma, nasal type]

Objective: To retrospectively analyze the clinical features and survival analysis of primary intestinal extranodal NK/T-cell lymphoma nasal type(ENKTL). Methods: Patients with intestinal lymphoma at the First Affiliated Hospital of Air Force Military Medical University were collected from January 2009 to December 2019, and those with primary intestinal ENKTL screened. The general situation, main symptoms, ECOG scale, lactic dehydrogenase(LDH), and β(2)-microglobulin(β(2)-MG)in the serum, lesion site and form, numbers of extranodal invasion, Lugano stage, pathological features, and lifetime and survival outcomes were evaluated. Results: In total, 34 patients with confirmed diagnosis of primary intestinal ENKTL were identified. The incidence rate of primary intestinal ENKTL is 16.2% (34/210). A total of 26 patients were men and 8 were women with the median age at diagnosis of 45 (range, 20-69)years and patients younger than 60 years account for 85.3%. It included abdominal pain (76.5%), diarrhea(20.6%), hematochezia(29.4%), and abdominal mass(2.9%), 85.3% with B-symptoms, and abnormally elevated LDH in the serum(73.5%). The lesion sites included large intestine(52.9%), small intestine(29.4%), and both of them(17.7%). The lesion forms were featured by mass(8.8%), ulcer(32.4%), diffuse infiltration(2.9%), and hybrid(55.9%). Lugano stage included stage Ⅰ/Ⅱ (70.6%)24 patients and stage Ⅳ(29.4%)10 patients. About 94.1% patients were EBER positive. The median survival time was 60 days. The overall survival rate had significant differences on ECOG scale, LDH in the serum, IPI score and complications(P=0.037, 0.009, 0.002, and 0.000, respectively). Conclusion: Primary intestinal ENKTL was commonly observed in men at young or middle age, and the most common symptom was abdominal pain, often with B-symptoms, abnormally elevated LDH in the serum. The most common site was the large intestine. The lesion forms were mainly featured by the hybrid and ulcer. It seemed that patients with IPI low-risk group and without any complication would have longer survival time.

Comparison of clinicopathological features and treatment outcomes in aggressive primary intestinal B- and T/NK-cell lymphomas

BACKGROUND

Primary intestinal lymphomas (PILs) are rare, and this study compared the clinical outcomes of aggressive primary intestinal B-cell lymphomas (aB-PILs) and T/natural killer-cell lymphomas (T/NK-PILs).

METHODS

The clinical information of patients diagnosed with aggressive PILs at our institution between 1995 and 2015 were retrospectively investigated. Pathological subtypes were confirmed according to the 2016 revision of the World Health Organization classification. The correlation between clinicopathological features and overall survival (OS) was determined using univariate and multivariate analyses.

RESULTS

Cases of T/NK-PILs had higher initial bowel perforation incidence (67% vs. 7%, P < 0.001) and lower complete response rate to first-line chemotherapy regimens (22% vs. 69%, P = 0.009) than aB-PILs. Patients with aB-PILs had a better 5-year event-free survival rate (55.8% vs. 13.9%, P = 0.026) and a 5-year OS rate (74.3% vs. 29.6%, P = 0.036) than those with T/NK-cell lymphomas. Multivariate analysis identified that female gender and stage III/IV were unfavorable prognostic factors. Among the 54 patients with diffuse large B-cell lymphoma (DLBCL), those with International Prognostic Index (IPI) scores of 0-2 had a better 5-year OS rate than those with scores of 3-5 (84.2% vs. 46.8%, P = 0.002). IPI scores of 3-5 (P = 0.026) and tumors located in the large intestine (P = 0.015) were poor prognostic factors based on the multivariate analysis.

CONCLUSION

The prognosis of T/NK-PILs was less favorable than that of aB-PILs. Female gender, stage III/IV disease, DLBCL with IPI scores of 3-5, or tumors in the large intestine were poor prognostic factors.