Clinicopathological analysis of 12 patients with Epstein-Barr virus-positive primary intestinal T/natural killer-cell lymphoma (EBV+ ITNKL)

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?

Endoscopic and clinicopathological characteristics of colorectal T/NK cell lymphoma

BACKGROUND

Colorectal T/natural killer (NK)-cell lymphomas (TNKCL) are very rare. Endoscopic and clinicopathological characteristics of colorectal TNKCL have not been clearly demonstrated. In this study, we demonstrated the clinical characteristics of colorectal TNKCL.

METHODS

Endoscopic and clinicopathological characteristics were investigated in 27 patients with colorectal monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), adult T-cell leukemia/lymphoma (ATLL), and other types of TNKCL.

RESULTS

Nine TNKCL patients (33%) were classified as MEITL, 11 (41%) as ATLL, and seven (26%) as other. Four patients with Epstein-Barr Virus-positive (EBV+) TNKCL, two indolent T-cell lymphoproliferative disorder and one anaplastic large cell lymphoma were included in the other group. Endoscopically, six MEITL (67%) and five ATLL (46%) showed diffuse-infiltrating type, in which the main endoscopic lesion was edematous mucosa in MEITL, while aphthoid erosion and edematous mucosa were typical in ATLL. Ulcerative type was identified in four other group patients (57%), including two EBV+ TNKCL. An increase in atypical T-intraepithelial lymphocytes (T-IELs) was noted in seven MEITL (88%) and six ATLL (60%) patients, but not in the other group (0%) patients. Five MEITL patients (56%) showed features of lymphocytic proctocolitis with increased CD8+ T-IELs.

CONCLUSIONS

MEITL and ATLL occasionally invaded the colorectum, and primary involving MEITL was observed. Diffuse infiltrating type was the characteristic endoscopic finding in colorectal MEITL and ATLL, while ulcerative type was observed in the other group. Features of lymphocytic proctocolitis may be prodromal findings of MEITL.

Extranodal NK/T-cell lymphoma in Tunisia: clinicopathological features, immunophenotype and EBV infection

BACKGROUND

Extranodal NK/T-cell lymphomas (ENKTL) are rare non-Hodgkin's lymphomas with aggressive clinical behavior. ENKTL are frequently associated with the Epstein-Barr virus (EBV). Data on ENKTL in Africa and Arab world are extremely limited. The study investigated the clinicopathological characteristics, EBV infection, and immunophenotype of ENKTL in Tunisia. We conducted a retrospective study of ENKTL. Main clinicopathological features were reported. The expression of CD3, CD4, CD5, CD8, CD20, CD56, CD57, and Granzyme B were analyzed by immunohistochemistry. EBV infection was detected by IHC (LMP-1) and Epstein-Barr encoding region (EBER1/2) in situ hybridization.

RESULTS

A total of nine ENKTL were identified (mean age of 48 years and male-to-female ratio of 8:1). There were five nasal ENKTL, and the remaining four cases had extranasal involvement (palate, sub-mandibular gland, skin, and soft tissues of the ankle). The histopathology showed a lymphoid and pleomorphic proliferation characterized by images of angiocentrism. Strong and diffuse CD3 expression was observed in all cases. Tumor cells exhibited an expression of CD5 (two cases), CD8 (three cases), CD56 (six cases), CD57 (three cases), and Granzyme B (eight cases). All ENKTL cases were EBV-associated. Overall 5-year survival rate was 57%. Although six ENKTL were diagnosed at early clinical stages, the prognosis was unfavorable and associated with patient death in three cases.

CONCLUSIONS

ENKTL are exceptional in Tunisia with unfavorable outcome. Histopathological diagnosis remains challenging in clinical practice. However, a careful histopathological examination combined with a correct interpretation of immunohistochemistry and in situ hybridization results refines the ENKTL diagnosis.

Nasal NK/T cell lymphoma mimicking mucosa-associated lymphoid tissue lymphoma in morphology: A case report

The objective of the present study was to describe the clinicopathological features of a patient with nasal NK/T cell lymphoma that was similar in morphology to mucosa-associated lymphoid tissue lymphoma (MALToma). The clinicopathological data of a patient diagnosed with nasal NK/T cell lymphoma mimicking MALToma was collected, and the clinicopathological characteristics were discussed. The female patient was 43 years old and had suffered from persistent congestion for ten days. The mucosa in the left nasal cavity was inflamed, resulting in congestion and it was also purulent on the surface, as observed by nasal endoscopy. The disease was considered to be inflammatory based on CT scan. A biopsy after operation showed that the tumor consisted of small lymphoid cells that resembled MALToma in morphology. On the basis of the immunohistochemistry and in situ hybridization laboratory tests, a diagnosis of left nasal NK/T cell lymphoma was made. The patient received chemotherapy and radiotherapy, and remission was achieved six months after diagnosis. The patient was in a good condition at 16 months follow-up. In conclusion, NK/T cell lymphoma composed of small cells may be a type of indolent lymphoma with special characteristics of clinical presentation, image, pathology and prognosis. This case highlights that more attention is required by radiologists, pathologists and hematologists to diagnose this type of lymphoma.

Primary Intestinal Epstein-Barr Virus-associated Natural Killer/T-cell Lymphoproliferative Disorder: A Disease Mimicking Inflammatory Bowel Disease

BACKGROUND AND AIMS

Primary intestinal Epstein-Barr virus [EBV]-associated natural killer/T-cell lymphoproliferative disorder [PIEBV+ NK/T-LPD] is a rare clinical entity, which is difficult to differentiate from inflammatory bowel disease [IBD]. We present a series of Chinese patients with PIEBV+ NK/T-LPD to increase awareness among clinicians of this condition.

METHODS

Patients diagnosed with PIEBV+ NK/T-LPD at West China hospital between 2014 and 2016 were included. Clinical and histopathological characteristics were reviewed, and key aspects of differential diagnosis were presented.

RESULTS

Twelve patients diagnosed with PIEBV+ NK/T-LPD were identified. Initial symptoms included intermittent fever [11/12 patients], abdominal pain [9/12], haematochezia [8/12], and diarrhoea [3/12]. Main endoscopic findings included multisegmental irregular, variable-sized ulcers, isolated giant ulcers, and diffuse inflammation. Colon and ileocaecum were mainly affected in 11 patients. The main PIEBV+ NK/T-LPD immunophenotypic profile of the infiltrating cells was CD3ε-positive NK/T cells characterised by positive T-cell intracellular antigen-1 and granzyme B, with CD5 deletion. In situ hybridisation was positive for EBV-encoded small RNAs 1/2 in all patients. Eleven patients were misdiagnosed with ulcerative colitis [4/11], Crohn's disease [4/11], or tuberculosis [TB, 3/11], owing to the similar endoscopic and histopathological features. The mean number of endoscopic procedures performed before reaching the diagnosis of PIEBV+ NK/T-LPD was 3.58; in four patients, the diagnosis was confirmed only after surgical resection following complications.

CONCLUSIONS

PIEBV+ NK/T-LPD may be difficult to differentiate from IBD or TB owing to overlapping endoscopic and pathological findings. Early identification of EBV reactivation in tissue samples is essential for the accurate diagnosis.

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.

CD30 expression and survival in extranodal NK/T-cell lymphoma: a systematic review and meta-analysis

Background

The paradoxical reports about the prognostic value of the CD30 expression in extranodal NK/T-cell lymphoma (ENKTL) have restricted its further applications in clinical practice. To identify the common effects and the variation, we conducted this systematic review and meta-analysis.

Methods

PubMed, MEDLINE, Embase, and Web of Science were searched between January 1975 and 31 January 2017. The pooled hazard ratio was used to estimate the effect of the CD30 expression on overall survival. Bias was assessed by prespecified criteria referring to Reporting Recommendations for Tumor Marker Prognostic Studies and Newcastle-Ottawa Scale.

Results

Ten retrospective cohort studies with 310 patients are included. CD30 is associated with better overall survival significantly (HR 0.71, 95% CI 0.51 to 0.99, I² = 0%). A greater effect is observed among studies including participants predominant in regional involvement (HR 0.31, 95%CI 0.13 to 0.76, I² = 0%) compared with those in systemic involvement.

Conclusions

This study indicates that the CD30 expression is significantly associated with better prognosis in ENKTL, especially for patients with regional lymphoma involvement.

Primary cutaneous NK/T-cell lymphoma of nasal type: an age-related lymphoproliferative disease?

Among extranodal NK/T-cell lymphoma of nasal type (NKTL), the extranasal variant (ENKTL) is known to have a worse prognosis with advanced clinical stage than the nasal variant of NKTL. However, detailed clinicopathological features of the localized extranasal disease have not been well documented in English literature. Here, we described the clinicopathological profiles of 14 patients with stage I ENKTL, including 7 in the skin, 5 in the gastrointestinal tract, and 2 in the central nervous system, highlighting the distinctiveness of the first. The 7 primary cutaneous (PCNKTL) cases were characterized by an older onset age (median, 76 versus 53 years, P=.012) and a more favorable clinical course (P=.041) compared with 17 patients with stages II-IV ENKTL that showed cutaneous involvement. The skin lesions in the PCNKTL group were distributed in the face or neck (n=4) and limbs (n=3) but not the trunk, which was most frequently affected (60%, P=.017) in the latter group. Furthermore, the stage I cutaneous disease showed a female predominance (male-female, 2:5 versus 7:0; P=.021) and a significantly more favorable survival compared with the noncutaneous stage I ENKTL (P=.037). These results suggest that PCNKTL constitute a distinct subgroup in the nasal-type lymphoma spectrum.