Nasopharyngeal and nasal malignant lymphoma: a clinicopathological study of 54 cases

Angioimmunoblastic T-cell lymphoma involving the nasopharynx: An easily misdiagnosed disease with atypical histopathological features

OBJECTIVES

To explore the clinicopathologic features, treatment, and survival outcomes of angioimmunoblastic T-cell lymphoma (AITL) involving the nasopharynx.

METHODS

We retrospectively analyzed 73 cases of AITL. Among them, 64 cases with complete pre-treatment 18F-FDG positron emission tomography/computed tomography (PET/CT) images were integrated into the analysis of clinical characteristics and PET/CT findings of AITL involving the nasopharynx; 14 cases with both biopsies from lymph node and nasopharynx were included in the comparison of pathological characteristics of AITL in the two areas. Forty-six of the 73 patients who received first-line systemic treatment at our institute were included in the treatment efficacy and survival analyses.

RESULTS

Nasopharyngeal involvement was seen in 44/64 (68.8%) patients. Histologically, lymph node and nasopharyngeal biopsies in 14 patients both showed small to medium-sized tumor cells, complex inflammatory infiltration, and Reed-Sternberg-like cells or B immunoblasts. However, tumor cells with clear cytoplasm, significant high endothelial venule (HEV) hyperplasia, and perivascular infiltration were observed in 5/14, 3/14, and 2/14 nasopharyngeal biopsies, respectively, but in all fourteen lymph node biopsies (P < 0.05). Immunophenotypic profiles and gene rearrangements were highly concordant. Treatment efficacy and survival were similar between patients with nasopharyngeal involvement and those without (P > 0.05), indicating nasopharyngeal involvement is not a prognostic factor for AITL patients.

CONCLUSIONS

Nasopharyngeal involvement is common in AITL but can be easily misdiagnosed because of its atypical pathologic pattern, especially when a lymph node biopsy is unavailable. However, the patient's clinical presentation, PET/CT manifestations, the typical immunophenotype, and gene rearrangements help the diagnosis.

Nasopharyngeal Lymphoma: Rare Case Report

A case of Nasopharyngeal Non Hogkins lypmhomas, diagnosed on Histopathology (HPE) and immunohistochemistry. In this case report we present the clinical presentation, diagnosis and treatment protocol of nasopharyngeal NHL.

Comparison of Primary B/NKT Non-Hodgkin Lymphomas in Nasopharynx, Nasal Cavity, and Paranasal Sinuses

OBJECTIVE

We aimed to compare clinical and survival differences between B-cell (B-NHL) and NKT-cell non-Hodgkin lymphomas (NKT-NHL) located in the nasal cavity (NC), nasopharynx, and paranasal sinuses, which are always categorized as one sinonasal type.

STUDY DESIGN

Patients diagnosed with primary B-NHL and NKT-NHL in the nasal cavity, nasopharynx, and paranasal sinuses from Surveillance, Epidemiology, and End Results (SEER) database were included (1975-2017).

SETTING

Population-based cohort study.

METHODS

We conducted univariate and multivariate Cox regressions and Kaplan-Meier analysis to examine survival outcomes of B/NKT-NHL in the nasal cavity, nasopharynx, and paranasal sinuses, respectively.

RESULTS

Overall, most B-NHL cases originated from the nasopharynx, while the majority of NKT-NHL cases occurred in the nasal cavity. Notably, the cancer-special survival (CSS) outcomes improved significantly in all sinonasal B-NHL cases over time, whereas no such improvement trend was observed in each sinonasal NKT-NHL type. Additionally, increasing age was linked with an elevated risk of death in B-NHL, particularly in the nasal cavity (Hazard ratio [HR]: 3.37), rather than in NKT-NHL. Compared with B-NHL, the adverse effect of a higher stage on CSS was more evident in NKT-NHL, particularly in its nasopharynx site (HR: 5.12). Furthermore, radiotherapy was beneficial for survival in patients with sinonasal B-NHL and NKT-NHL, except in the nasopharynx NKT-NHL. However, chemotherapy has only been beneficial for CSS in patients with paranasal sinuses B-NHL (HR: 0.42) since 2010, rather than in other types of B/NKT-NHL.

CONCLUSION

Although B-NHL and NKT-NHL in the nasal cavity, nasopharynx and paranasal sinuses have similar anatomical locations, their clinicodemographics and prognoses are largely different and should be treated and studied as distinct diseases.

Nasopharyngeal Lymphoma: A 22-Year Review of 35 Cases

Nasopharyngeal (NP) lymphoma is a rare primary malignancy of the head and neck and represents a minority of malignancies originating from the nasopharynx. For this reason, there are limited data regarding epidemiologic and treatment outcomes. This is a retrospective review of patients diagnosed with NP lymphoma from 1995 to 2017 at a tertiary medical center. The patients’ demographic data, clinical presentations, treatment modalities, Epstein–Barr virus (EBV)-encoded small RNA (EBER) staining, and outcomes were investigated. We considered a total of 35 patients, including 20 males and 15 females, diagnosed with NP lymphoma. The age ranged from 17 to 88 years (mean = 59.6). The common presentations were nasal obstruction, epistaxis, and neck mass. In our study, the most common pathological diagnosis of NP lymphoma was diffuse large B cell lymphoma (DLBCL) (n = 17), followed by NK/T cell lymphoma (NKTCL) (n = 9). Other pathologic diagnoses included extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALToma), small lymphocytic lymphoma, mantle cell lymphoma. There were 13 cases showing EBER positivity, including 7 cases of NKTCL, 5 cases of DLBCL, and 1 case of post-transplant lymphoproliferative disorder (PTLD). Most patients received chemotherapy alone, while some patients received both chemotherapy and radiotherapy. Seven patients had local recurrence, and fewer than half of the patients (n = 16) were alive at the time of the study (mean follow-up duration: 54.4 months). The five-year overall survival was 50.4%. NP lymphoma is very rare, and the most common pathologic type is DLBCL. EBER positivity is found in both NKTCL and DLBCL. Identifying more effective therapeutic agents is extremely important to improve patients’ survival.

Epidemiology of Nasopharyngeal Lymphoma in the United States: A Population-Based Analysis of 1119 Cases

Objectives To describe the incidence and determinants of survival of patients with nasopharyngeal lymphoma (NPL) between 1973 and 2012 using the Surveillance, Epidemiology, and End Results (SEER) database. Study Design Retrospective cohort study using a national database. Methods The SEER registry was used to calculate survival trends for patients with NPL between 1973 and 2012. Patient data were then analyzed with respect to histopathology, age, sex, race, histologic subtype, Ann Arbor stage, and whether radiation therapy was given. Overall survival (OS) and disease-specific survival (DSS) were calculated. Results A total of 1119 cases of NPL were identified. The cohort was composed of 58.8% males. The mean age at diagnosis was 59.3 years. The median OS was 8.2 years. B-cell non-Hodgkin's lymphomas (NHLs) accounted for most cases (77.5%), with natural killer (NK)/T-cell lymphomas comprising 6.0% of cases. A total of 41.5% patients received radiation therapy. OS at 2, 5, and 10 years was 70%, 57%, and 45%, respectively. On multivariate analysis, advanced age and NK/T-cell NHL histologic subtype were associated with worse OS and DSS, while radiation therapy was associated with improved OS and DSS (all P < .05). Conclusion With the exception of NK/T-cell NHL subtypes, NPL is associated with a fair prognosis, with younger age, low Ann Arbor stage, and radiation therapy being independent positive prognosticators for survival.

Primary extranodal non-hodgkin lymphoma of the head and neck in patients with acquired immunodeficiency syndrome: a clinicopathologic study of 24 patients in a single hospital of infectious diseases in Argentina

Introduction Extranodal non-Hodgkin lymphomas (NHLs) are commonly described in patients with acquired immunodeficiency syndrome (AIDS) and are related with an atypical morphology and aggressive clinical course. AIDS-associated lymphomas are characterized by their rapid progression, frequent extranodal manifestations, and poor outcome. Objective The aim of this article is to remake the clinical features of head and neck (HN) NHL in patients with AIDS to facilitate early diagnosis and treatment. Methods We evaluated the epidemiologic, clinical, immunologic, virologic, and histopathologic characteristics of 24 patients with human immunodeficiency virus (HIV)/AIDS with primary HN NHL treated at a single institution between 2002 and 2012. Histopathologic diagnosis was made according to the criteria of the World Health Organization Classification of Tumors of Hematopoietic and Lymphoid Tissues. Additional immunohistochemical stains were applied in all cases. Results Eighteen patients (75%) were men and the median of age was 39 years. The gingiva and the hard palate were the most common sites of the lesions (15 patients, 62.5%). Lactate dehydrogenase levels were elevated in 16 cases (84%). Bone marrow infiltration was detected only in 4 cases (16.6%). The median CD4 T-cell count was 100 cells/µL. According to the histopathologic evaluation, the most common subtype was diffuse large B-cell lymphoma (12 cases, 50%), followed by plasmablastic lymphoma (9 cases, 37.5%) and Burkitt lymphoma (3 cases, 12.5%). Conclusion HN NHL is a severe complication of advanced HIV/AIDS disease. Early diagnosis followed by chemotherapy plus highly active antiretroviral treatment is necessary to improve the prognosis and the survival of these patients.

Nasopharyngeal Extranodal NK/T-Cell Lymphoma, Nasal Type: Retrospective Study of 18 Consecutive Cases in Guangzhou, China

Objective: The aim of this study was to investigate the frequency and clinicopathologic features of nasopharyngeal extranodal NK/T-cell lymphoma, nasal type (NKTCL), as well as DNA sequence variation of Epstein—Barr virus (EBV) in neoplastic cells harboring in NKTCLs from Guangzhou district. Materials and methods: The clinical data of 18 unselected consecutive nasopharyngeal NKTCLs in one institution were reviewed retrospectively. Immunohistochemical staining and EBV-encoded RNAs (EBERs) in situ hybridization were applied. DNA extraction, polymerase chain reaction (PCR), nested PCR, and sequencing for analyzing the C-terminal and N-terminal regions of LMP1 gene as well as BamHI F fragment of EBV were applied in 16 available samples. Results: NKTCLs accounted for 69.2% (18/26) of nasopharyngeal T- and NK-cell lineage non-Hodgkin lymphomas. In all, 10 out of 18 patients (55.56%) had cervical lymph node(s) involvement. The serum anti-EBV antibody level was elevated (VCA-IgA titer ≥1:40) in 6 of 12 available patients. Two major immunophenotypic subtypes, namely, TIA-1+/EBERs+/CD56+ (10 cases) and TIA-1+/EBERs+/CD56- (8 cases) could be recognized. Genotyping analysis revealed that 10 out of 13 cases (76.9%) of NKTCL were harbored with del-LMP1 [del-LMP1 (Gly335) variant 7 cases, del-LMP1 (Asp335) variant 3 cases]. XhoI-loss was shown in 8/11 cases (72.73%). BamHI “f” variant of Bam F fragment was shown only in 4/14 cases (28.57%).The most common combination was del-LMP1 (Gly335)/ XhoI-loss/F (6/9, 66.7%). Conclusions: The majority of nasopharyngeal T- and NK-cell lymphomas are NKTCL in Guangzhou district. The patients often have involvement of cervical lymph node(s) and an elevated level of serum anti-EBV antibodies. The CD56 expression rate seems lower than that found in sinonasal NKTCL. The most common EBV variant harboring in nasopharyngeal NKTCL seems somewhat different from that harboring in nasopharyngeal carcinoma in Guangzhou.

Primary non-Hodgkin's lymphoma of the nasopharynx: Prognostic factors and outcome of 113 Indian patients

This single institutional study evaluated the prognostic factors and treatment outcome of 113 Indian patients with primary nasopharyngeal non-Hodgkin's lymphoma. At presentation, 28% had stage I and 62% had stage II disease. Treatment comprised of a combination of chemotherapy (CTh) and radiotherapy (RT) in the majority of the patients (76%). After a median follow-up of 56 months, the 5-year disease-free survival (DFS) and overall survival (OS) for the whole group were 55.8% and 57.9%, respectively. Multivariate analysis showed that; age > 30 years [hazard ratio (HR) = 6.59, 95% confidence interval (CI) = 2.59 - 16.7, P < 0.0001], WHO performance score > or = 2 (HR = 2.34, 95% CI = 1.01 - 5.46, P = 0.050), T-cell lymphomas (HR = 2.81, 95% CI = 1.14 - 6.96, P < 0.001) and the presence of B symptoms (HR = 3.65, 95% CI = 1.77 - 7.53, P = 0.025), had a negative influence on survival. Patients treated with a combination of CTh and RT had a significantly better outcome than those treated with CTh alone (OS: 69%vs. 31%, P < 0.00001). HR for death in the CTh alone group was 3.73 (95% CI = 1.95 - 7.13). The CR (P = 0.01), DFS (P = 0.01) and OS (P = 0.03) rates were significantly better for patients receiving a RT dose of > or =4500 cGy. HR in the subgroup that received a RT dose of <4500 cGy was 2.51 (95% CI = 1.04 - 6.06). These results suggest that combined modality treatment, comprising of CTh and RT (with an RT dose of > or =4500 cGy), results in satisfactory outcome in patients with this rare neoplasm.

A 2.6 Mb interval on chromosome 6q25.2-q25.3 is commonly deleted in human nasal natural killer/T-cell lymphoma

Natural killer (NK)/T-cell lymphoma is a special subtype of rare malignant lymphoma that is more prevalent in Asia than in America and Europe. This newly characterized haemato-lymphoid malignancy is highly aggressive and frequently present in nasal and upper aerodigestive sites. Several studies have reported the commonly deleted region of chromosome 6q21-25 in this particular type of lymphoma. To refine the smallest region of overlapping (SRO) deletion for localization of potential tumour suppressor (TS) genes, we performed loss of heterozygosity (LOH) and homozygosity mapping of deletion (HOMOD) analyses on 37 nasal and nasal-type NK/T-cell lymphoma patients using a panel of 25 microsatellite markers, covering the 6q21-q25 region. In all patients studied, LOH was detected in eight (89%) paired-sample patients, while hemizygous deletion was detected in three (11%) single-sample patients. Combination of the LOH and HOMOD results defined a distinct 3 Mb SRO on chromosome 6q25. Quantitative multiplex polymerase chain reaction analysis of 10 sequence-tagged sites further refined the putative TS-gene-containing region to a 2.6 Mb interval between TIAM2 and SNX9. Eighteen known genes/Unigene clusters and 25 hypothetical genes are located within this 2.6 Mb region, but none are previously identified TS genes. These results provide a framework for future positional cloning of novel TS gene(s) at 6q25.2-q25.3.

Primary Adenoidal Hodgkin's Disease: Report of a Case with an Unusual Morphology and Review of the Literature

The nasopharyngeal lymphoid tissue (adenoids) is an uncommonly reported primary site for Hodgkin's disease. We report a case of primary adenoidal, interfollicular, epithelioid cell-rich variant of mixed cellularity Hodgkin's disease. The combination of an interfollicular pattern and richness of epithelioid histiocytes made it very difficult to make the diagnosis of Hodgkin's disease without the help of immunohistochemistry. To our knowledge, only 39 cases of Hodgkin's disease primarily involving the Waldeyer's ring have been reported in the English literature, 24 of these primarily involving the adenoids. Our case shows the difficulty encountered in making the diagnosis when a very unusual morphologic appearance of Hodgkin's disease is seen at a rare presentation site. The appropriate immunohistochemical work-up should be performed in unusual lymphohistiocytic proliferations involving the Waldeyer's ring. Int J Surg Pathol 8(3):241-246, 2000

Primary nasal and nasopharyngeal lymphomas: a comparative study of clinical presentation and treatment outcome

Primary nasal lymphoma (NSL) and nasopharyngeal lymphoma (NPL) are uncommon extranodal lymphomas that have often been grouped together in studies published in the literature. It is unclear whether or not NSL and NPL are biologically different entities. We reviewed the records of 25 NSL and 19 NPL patients who were managed between 1985 and 1995, to evaluate and compare their clinical characteristics and treatment outcome. Clinical variables, including age, sex, stage, tumour bulk and treatment modality, were assessed for their prognostic influence on survival. Nasal obstruction (80%), nasal discharge (64%) and epistaxis (60%) were the predominant symptoms in NSL patients; neck swelling/mass (42%), nasal obstruction (37%) and hearing impairment (32%) were common findings in NPL patients. Limited stage disease (I/II) was present in all NSL and in 80% of the NPL patients. Thirty-six per cent of the NSL and 32% of the NPL patients had bulky disease. The majority of the immunophenotyped NSLs were of T-cell lineage (75%, 12/16) and most immunophenotyped NPLs were of B-cell lineage (69%, 11/16). The patients were treated with radiotherapy alone (14%), chemotherapy alone (23%) or chemotherapy plus radiotherapy (64%). NSL patients showed a lower complete remission rate and higher relapse rate than NPL patients, although the difference did not reach statistical significance. Both the 5-year disease-free survival (36% versus 76%; P = 0.007) and overall survival (33% versus 82%; P = 0.003) were significantly worse in NSL compared with NPL patients. Advanced age (>60 years; P = 0.03) and bulky disease (P = 0.04) were also associated with inferior survival times. The analysis of sex, stage and type of therapy showed no evidence of significant impact on the survival. Despite the close anatomical relationship in origin, NSL and NPL were noted to behave as biologically distinct entities, in which the NSLs demonstrated a higher frequency of T-cell tumours and a much worse prognosis than NPL. In addition to the primary site, advanced age and bulky disease were also associated with reduced survival.

Primary non-Hodgkin's lymphoma of the nasal cavity: prognostic significance of paranasal extension and the role of radiotherapy and chemotherapy

BACKGROUND

This study was conducted to determine whether the paranasal extension of a primary non-Hodgkin's lymphoma (NHL) of the nasal cavity has any deleterious effect on patient outcome.

METHODS

One hundred and seventy-five patients with previously untreated nasal NHL were reviewed. There were 2 with low grade, 107 with intermediate grade, 17 with high grade, and 49 with unclassifiable lymphomas. In 48 cases the immunophenotype was available and 46 were T-cell lymphoma. According to the Ann Arbor system, there were 133 patients with Stage IE, 28 with Stage IIE, 4 with Stage IIIE, and 10 with Stage IVE lymphomas. Stage IE was subdivided into limited Stage IE (i.e., confined to the nasal cavity [67 patients]) or extensive Stage IE (i.e., presenting with extension beyond the nasal cavity [66 patients]). For patients with limited Stage IE disease the treatment of choice was radiotherapy with or without chemotherapy. In patients with extensive Stage IE disease, treatment was comprised of a combination of chemotherapy and radiotherapy or radiotherapy alone. For patients with a more advanced stage of disease (IIE-IVE), chemotherapy was an integral part of the treatment and was completed by irradiation, especially for patients with Stage IIE disease.

RESULTS

The actuarial overall survival (OS) and disease free survival (DFS) rates at 5 years for the whole group were 65% and 57%, respectively. The 5-year OS and DFS rates were influenced by stage, with a gradual decrease from 75% and 68% for Stage IE disease to 35% and 28% for Stage IIE disease, and 31% and 19% for Stage IIIE/IVE disease. Patients with limited Stage IE disease survived significantly longer (90% 5-year OS) compared with those with extensive Stage IE disease (57% 5-year OS; P < 0.001). For 67 patients with limited Stage IE disease, the 5-year OS was 89% with radiotherapy alone and 92% with radiotherapy and chemotherapy, whereas for 66 patients with extensive Stage IE disease, the 5-year OS was 54% with radiotherapy and 58% with combined modality therapy or chemotherapy (P > 0.05).

CONCLUSIONS

The prognosis of patients with primary NHL of the nasal cavity is stage dependent. In this large cohort of Stage IE patients, it was demonstrated that the paranasal local extension was a significant prognostic factor associated with poorer treatment outcome. The authors believe that Ann Arbor Stage IE should be subclassified further into limited and extensive Stage IE. The addition of chemotherapy did not appear to modify significantly the survival of patients with either limited or extensive Stage IE disease. The extranodal progression observed in patients with extensive Stage IE and Stage IIE-IVE disease clearly illustrates the need for improvement of systemic treatment.

Nasal lymphoma: results of local radiotherapy with or without chemotherapy

BACKGROUND

Primary nasal lymphoma is a rare disease. Although most patients are initially seen in early Ann Arbor stages, their prognosis is poor. The prognostic significance of local tumor bulk has not been well studied.

METHODS

Twenty-one patients with nasal lymphoma treated between 1985 and 1992 were retrospectively studied. Sixteen patients (76%) below the age of 75 years received combined radiotherapy and chemotherapy. One young patient with early disease and 4 elderly patients had radiotherapy alone. Twelve cases (57%) were diagnosed as pleomorphic T-cell lymphoma based on typical histologic features alone. Immunophenotyping was performed in 10 cases; 8 were T cell and 2 were B cell. Seventeen patients (81%) had Ann Arbor clinical stage IE disease, and 4 had stage IIE disease. The local tumor extent was assessed by endoscopy in all patients and by computerized tomography (CT) in 14 patients. Eleven local tumors (52%) extended to the posterior ethmoids, sphenoid sinus, orbit, or beyond. Using a T-stage system, the prognostic significance of local tumor bulk was evaluated for stage IE patients.

RESULTS

At a median follow-up time of 16.8 months, the lymphoma recurred in 13 patients; 10 patients had systemic relapse and 10 patients, local relapse. The 5-year actuarial overall survival rate was 24%. Complete response to chemotherapy was achieved in 5 of 16 patients (31%). Four of the 6 patients who remained alive and disease-free were chemotherapy complete responders. Among stage IE patients, those with early and those with advanced local disease did not have significantly different survival.

CONCLUSIONS

In view of the high systemic and local relapse rates, more-effective chemotherapy is needed to improve the survival rates, and the role of combined chemotherapy and radiotherapy should be evaluated. Further studies are required to identify patients at high risk of relapse for clinical trials with investigational treatment.

Clinicopathologic study of nasal T/NK-cell lymphoma among the Japanese

A high prevalence of nasal lymphoma expressing a T- or natural killer (NK)-cell phenotype (NTCL) with frequent association of Epstein-Barr virus (EBV) has been indicated in Asians. To characterize NTCL among the Japanese, the clinicopathologic features of 32 cases were evaluated and the cases were also analyzed for EBV-RNA using an ISH method. Morphologically, 31 cases were identified by atypical pleomorphic lymphoid infiltrates with polymorphous, angicentric, and necrotic features. Their lymphoma cells ranged in size from small to large and were mixed in varying proportion from case to case. The other one case showed a monomorphic 'blastic' appearance. EBV-encoded small RNA (EBER) was detected in the neoplastic cells of 27 of the 32 cases examined. In the five EBV-negative cases, one was the 'blastic' type. Clonal T-cell receptor gene rearrangement was detected in none of seven cases examined. The patients had a median follow-up of 9 months (range, 1 month to 14 years and 11 months). The Kaplan-Meier estimate of overall survival was 49% at 5 years, correlating with clinical stage. These data support the concept that most cases of NTCL are identified as tumors with T/NK-cell characteristics and EBV association, distinctly different from other peripheral T-cell lymphomas. Furthermore, the one case of an EBV-negative 'blastic' variant appears not to fit well into the pleomorphic category but more closely resembles the pathologic features of extranasal angiocentric lymphoma with lymphoblastoid appearance. This study also showed no clear difference in clinical aspects other than the original site or in prognosis, between NTCL and extranasal angiocentric lymphomas despite the higher incidence of EBV association and the tendency for that peculiar anatomical site to be restricted to the former group.

Nasopharyngeal lymphomas: further evidence for a natural killer cell origin

The authors report four cases of sinonasal lymphomas with immunophenotypic (four cases) and genotypic (three cases) studies. These lymphomas are frequent in Oriental countries, but unusual in Western populations, particularly in France. Although they have been originally considered as T-cell lymphomas, their origin remains unclear, and several authors have recently suggested that they are a natural killer (NK)-cell proliferation. The tumor cells of the four cases reported here showed characteristics of NK cells. On cryostat sections, they were CD3 negative, but CD2 and CD56 positive. The cytoplasm of the tumor cells exhibited azurophilic granulations. Using polymerase chain reaction (PCR), no clonal rearrangement of the T-cell receptor gamma gene was present. Furthermore, clinically, two presented a pharyngeal involvement, and two were also characterized by hepatosplenic involvement at the time of the diagnosis. Thus, the present cases provide additional evidence toward the NK-cell origin of these rare lymphomas. Many sinonasal lymphomas, including the present cases, are positive for Epstein-Barr virus (EBV) (LMP-1 antibody and EBER-messenger RNA probes). This may suggest an important role of EBV as a local factor in their pathogenesis.

Malignant Transformation of Nasopharyngeal Lymphoid Hyperplasia

Lymphadenopathy and nasal obstruction are very common in the HIV-positive patient and may or may not reveal a nasopharyngeal tumor. Biopsy is warranted if there is evidence suggestive of lymphoma or other neoplastic disease. This would include progressive rapid enlargement observed on examination or CT scan, an asymmetric growth pattern, and evidence of invasion of normal anatomic boundaries. It is certain that not all cases of adenoid hypertrophy that occurs early in the course of HIV disease represent a malignancy. Further study is needed to determine the proper timing for nasopharyngeal biopsy in the HIV-positive population. As the life span of the HIV-positive patient increases, so may the incidence of malignant degeneration.

Nasal T-cell lymphoma: a clinicopathological and immunophenotypic analysis of 13 cases

Thirteen cases of nasal lymphomas with T-cell or natural killer (NK)-cell phenotype were studied, with attention to clinical presentation and follow-up, the presence of Epstein-Barr virus (EBV) using in situ hybridization (EBER), the immunophenotype, and the presence of cytotoxic granules. All but two patients presented with stage I disease. In three cases local progression resulted in involvement of the central nervous system. When dissemination occurred, this was predominantly to extranodal localizations, in two cases to the skin. Response to therapy was highly variable, but patients treated with radiotherapy with or without additional chemotherapy had a better prognosis than patients treated with initial chemotherapy alone. All lymphomas were associated with EBV, and most cases showed cytotoxic features, ten of which were CD56 positive. In eight cases a T-cell origin was proven, but in five cases a possible NK-cell origin could not be excluded. No clinical differences were seen between true T-cell lymphomas and possible NK-cell neoplasms. Nasal T-cell lymphomas should be considered as a distinct clinicopathological entity, strongly associated with EBV, and with cytotoxic features in most cases. No prognostic parameters were detected to predict dissemination and response to therapy.

Epstein-Barr virus infection in sinonasal non-Hodgkin's lymphomas

Sinonasal non-Hodgkin's lymphomas (SNHLs) of B- or T-cell immunophenotype have been associated with Epstein-Barr virus (EBV) infection of neoplastic lymphoid tissue. Nine SNHLs were investigated using immunohistochemistry, the polymerase chain reaction (PCR) for EBV genome and in situ hybridization (ISH) for EBV encoded RNAs (EBER), immunoglobulin (CI-gHR) and clonal T-cell receptor (CTC beta R) gene rearrangements. Eight cases were diagnosed as peripheral pleomorphic T-cell lymphomas (pPTCL). PCR showed the presence of EBV genome in eight cases; ISH for EBER led to the detection of positive cells in five cases. Late membrane protein (LMP) immunostaining was observed in three cases. No EBV positivity has been detected in control cases. The frequent association with EBV infection in the cases illustrated confirms the previous suggestions that EBV may have a role in the genesis of lymphomas of the sinonasal region.

Waldeyer ring lymphomas. A clinicopathological study of 79 cases

Waldeyer ring lymphomas belong to a category of tumours which has not yet been fully defined. Their relation to mucosa-associated lymphoid tissue (MALT) and other extranodal lymphomas remains largely unknown. We performed a clinicopathological retrospective study of 79 patients, and compared them with a series of MALT and nodal lymphomas. Tumours from the nasopharynx and palatine tonsil showed similar histological profiles, with a predominance of large B-cells. Centroblastic lymphomas constituted the largest group (n = 45), followed by those of centrocytic type (9) with smaller groups of centroblastic-centrocytic (5) and Hodgkin's lymphomas (2). Three monocytoid B-cell lymphomas were identified. Only one case could be classified as MALT lymphoma. The frequency of bcl-2 expression in large B-cell tumours of Waldeyer's ring has an intermediate range between large B-cell lymphomas occurring in mucosal and nodal locations. Epitheliotropism was present in all low-grade cases, and was therefore not a useful marker in the identification of potential MALT lymphomas in contrast with other mucosal sites. Comparative survival studies showed significant overall differences between Waldeyer ring lymphomas, MALT and nodal cases. These disappeared after taking stage and histological grade into account. We conclude that Waldeyer ring lymphomas show distinctive features, mainly in terms of histological distribution and immunophenotype. The key factor determining their behaviour could be their different spreading capability. These findings suggest that extranodal lymphomas are heterogeneous, and indicate the need for additional efforts to clarify this.