Primary Lymphomas of the Brain: A Clinico-Pathologic Review of 37 Cases

Primary Lymphoma of the Central Nervous System

Primary lymphoma of the central nervous system (CNS) represents a pathology that is no longer considered rare, also in the light of its high correlation with the human immunodeficiency virus (HIV) syndrome reported recently. Often the correct diagnosis of the disease is difficult to reach, owing to the wide spectrum of non-lymphoma pathologies from which it should be differentiated and the invasiveness of some diagnostic techniques. The biologic aggressiveness of the neoplasm often makes a combined radio-chemotherapeutic approach necessary. In contrast, surgical resection does not seem to provide any significant benefit. The clinical experience reported here, together with a review of the most recent literature, lead the authors to suggest the opportunity of treating primary lymphoma of the CNS with the most active and modern chemotherapeutic protocols in association with traditional treatments to obtain an improvement in overall survival.

Primary brain T-cell lymphoma of the lymphoblastic type presenting as altered mental status

The authors present a case of a 56-year-old man with altered mental status. Magnetic resonance imaging (MRI) of the brain revealed non-enhancing abnormalities on T2 and FLAIR imaging in the brainstem, cerebellum, and cerebrum. Immunohistochemisty demonstrated precursor T-cell lymphoblastic lymphoma. After treatment with methotrexate, he improved clinically without focal sensorimotor deficits and with improving orientation. MRI showed almost complete resolution of brainstem and cerebral lesions. To the authors’ knowledge, there are only five previous reports of primary central nervous system T-cell lymphoblastic lymphoma. Since treatable, it deserves consideration in patients with altered mental status and imaging abnormalities that include diffuse, non-enhancing changes with increased signal on T2-weighted images.

Primary central nervous system non-Hodgkin's lymphoma: survival advantages with combined initial therapy?

PURPOSE

Results of multiple radiation, chemotherapy, and combined treatment trials have shown that the fate of primary central nervous system lymphoma (PCNSL) patients is very different from that of patients with similarly treated systemic IE non-Hodgkin's lymphoma. This study was designed to improve the survival of PCNSL patients by the use of combined initial therapy.

METHODS AND MATERIALS

Forty-six eligible primary PCNSL patients were treated with whole brain irradiation and adjuvant chemotherapy consisting of preirradiation cyclophosphamide-adriamycin-vincristine-prednisone (CHOP) and postirradiation high-dose cytosine arabinoside (HDAC) as part of an ongoing Phase II Mayo/North Central Cancer Treatment Group/Eastern Cooperative Oncology Group (M/NCCTG/ECOG) intergroup effort, which opened in April 1986.

RESULTS

This cohort consisted of 23 men and 23 women with median age 63.5 years (range 24 to 75 years). Only 5% were under age 40; 36% were age 40 to 59, 37% were age 60 to 69, and 22% were age 70 and over. Forty-six percent had good performance scores of ECOG 0-1 at time of study entry. Forty-six patients were evaluable for treatment outcome as of October 6, 1993. Of these, 10 were still alive. Estimated median survival and 21-month survival were 45.3 weeks and 29%, respectively. There were four early deaths ranging from Day 9 to Day 15 (three drug-related, one from other complications), and two CHOP responders died at 32 and 35 days, soon after Cycle 2 of CHOP (one probably drug-related, one from other complications). There was no significant difference in survival according to baseline performance status. However, survival was consistently worse for patients > 60 years old than for the younger patients (< or = 60 years). With deaths recorded for 21 of 21 older patients, but only 9 of the 14 younger patients, 21-month survival for older vs. younger was 14 vs. 50% based on the 35 patients who entered the study at least 21 months ago (p = 0.0365). Of the 46 patients evaluable for response, 63% had objective remissions on CHOP and another 20% remained stable.

CONCLUSION

Combined modality therapy in this study did not produce an overall survival advantage in treating PCNSL. The 50% 21-month survival of younger patients may be a reflection of age only.

Primary lymphoma of the spinal cord

Non-Hodgkin's lymphomas arising in the spinal cord are extremely rare. Only eight single case reports have been well confirmed in the literature. Herein we describe a 59-year-old woman with symptoms attributable to a spinal cord lesion. Physical examination revealed neurologic deficits but no evidence of tumor elsewhere. Although several imaging studies were performed, only magnetic resonance imaging with use of gadolinium revealed the exact site and extent of the lesion. Laminectomy and direct examination of the spinal cord disclosed a discolored region at the level of the 11th thoracic vertebra. A biopsy specimen was obtained, and pathologic examination revealed an intermediate grade, mixed cell lymphoma of T-cell origin. Radiotherapy was administered to the lesion and adjacent region of the spinal cord with use of 6-MV photons and an anteroposterior-posteroanterior technique; the total dose was 45 Gy in 23 fractions. No chemotherapy was given. After 3 years of follow-up, the neurologic signs and symptoms were stable, and repeated magnetic resonance imaging with use of gadolinium showed no residual tumor. In addition to the case report, we review the literature on primary lymphomas of the central nervous system and discuss treatment recommendations.

Primary brain lymphoma. A brief review of clinical aspects and management

Primary C.N.S. lymphoma is a rare tumor. Five such cases were treated in our clinic between January, 1991, and October, 1993. Four patients had tumor decompression and one had total resection. All of them received radiotherapy (radiation dose 40 Gy) and chemotherapy. One patient expired during the immediate postoperative period. Four patients showed a disappearance of the tumor on CT scan after the complete course of therapy of 9 months. Three patients showed recurrence intracranially at 15, 12, and 10 months. All patients died during follow up except one, who has been alive without recurrence for 10 months. Median survival was 13 months.

Non-Hodgkin lymphomas of the central nervous system. Clinico-pathologic and immunohistochemical study of 147 cases

We report on data gathered from five European centres regarding 147 primary non-Hodgkin Lymphomas (NHLs) of the Central Nervous System (CNS) in HIV-negative patients. The results lead us to make the following considerations: i) there has been a significant and progressive increase in the frequency of observation of this pathology during the course of the last two decades; ii) the pathology lacks specific characteristic symptoms; iii) the radiological profile, as observed by CAT and/or MNR, most frequently corresponds to an isodense or slightly hyperdense lesion which has clear margins and is capable of assuming the contrast medium homogeneously; iv) the tumour most often has a single supratentorial localisation; v) high grade B-cell lymphomas account for 66% of the observations, low grade B-cell varieties being relatively rare and cases of T-cell derivation exceptional (6/147); vi) immunohistochemistry allows the differential diagnoses with respect to primitive or secondary non-lymphoid tumours, and provides confirmation of the histogenetic assessment made on morphological grounds; vii) the course of the disease is not significantly influenced by the histotype, the phenotype, the number of lesions present or the chemotherapy regimen, but rather by the employment of combined surgery and radio- or radiochemotherapy. This study represents the largest series of CNS NHLs so far reported, and as such, provides precise clinico-pathological indications which were only partially obtainable from the relatively small previously published series. Some concluding remarks are made as to the genesis of CNS NHLs, along with some practical suggestions for reaching a better understanding of their complex biology.

Primary T-cell malignant lymphoma of the central nervous system. Histological, immunohistochemical and ultrastructural study of a case

Most primary malignant lymphomas (ML) of the central nervous system (CNS) are derived from B-cells, whereas T-malignant lymphomas (T-ML) primarily arising in the CNS are extremely rare. We report on a patient with a primary T-ML of the CNS localised in the posterior fossa. On the basis of histological, ultrastructural and immunohistochemical studies, this tumour was classified as a pleomorphic T-ML, medium and large cell type with peripheral helper/inducer T-cell phenotype (CD 1-, CD 2+, CD 3+, CD 5+, CD 7-, CD 4+, CD 8-, CD 19-, CD 22-, UCHL 1+/CD 45 RO, L 26-/CD 20, LN 1-/CDW75, LN 2-/CD 74, MB 2-). Furthermore, the positivity of the markers CD 25 and HLA-DR on many medium-sized and large lymphoma cells suggests activation of these cells. The nuclear marker of proliferative activity Ki-67 was expressed in some large cells, whereas the natural killer cell-related markers CD 16 and Leu 7/CD 57 did not react with lymphoma cells. This study emphasises the value of extensive immunohistochemical investigations on frozen and paraffin sections in order to identify and characterize the T-cell malignancies, particularly in their rare CNS location.

Primary cerebral lymphoma: a study of 47 cases probed for Epstein-Barr virus genome

AIMS

To determine the prevalence of Epstein-Barr virus genome in primary cerebral lymphomas occurring in the absence of immune suppression.

METHODS

Forty eight consecutive patients with lymphomas restricted to the central nervous system were identified, all of whom had had neurosurgical biopsies performed at the National Hospitals for Neurology and Neurosurgery, London. Only five patients had some form of underlying immune deficiency; 43 were apparently normal. The tumours were studied with immunohistochemical markers and by in situ hybridisation, using a biotinylated probe to the internal repeat region of Epstein-Barr virus.

RESULTS

All the lymphomas were B cell in origin. Tumours from the five immunosuppressed patients all showed hybridisation, as did two of the "spontaneous" tumours.

CONCLUSIONS

This is the largest series of cerebral lymphomas so far probed for Epstein-Barr virus genome: as more are examined, it is suggested that a small proportion of the tumours from immunocompetent patients will also contain the virus.

Primary central nervous system lymphomas--an update

Primary CNS lymphomas (PCNSL), until recently representing about 1% of all brain tumors, show dramatically increased incidence both in high-risk groups (immunocompromised, AIDS) and in the general population. They are extranodal diffuse non-Hodgkin's lymphomas, the morphology and classification of which are identical to those of systemic lymphomas, although PCNSL show different biological behavior and diagnosis according to the New Working Formulation and updated Kiel classification may be difficult. The majority are large B cell variants of high-grade malignancy; low-grade subtypes and T cell lymphomas are rare. Sixty per cent occur in the supratentorial space (hemispheres, periventricular) and 12% in the posterior fossa; 30% are multiple (50%-70% in AIDS). PCNSL show a male preponderance with a peak incidence in the 5th-7th decade (3rd-4th in AIDS). The duration of diffuse or focal clinical symptoms averages 1-2 months. Computed tomography and magnetic resonance imaging scans show single or multiple or diffuse, often typical lesions. Diagnosis is achieved by evaluation of stereotactic biopsy material or cerebrospinal fluid cytology using immunocytological markers. Current therapy in immunocompetent patients, radiation plus corticosteroids and pre- or postradiation polychemotherapy, shows response rates of 85% with a median survival of 17-44 months, a prognosis similar to that for glioblastoma. Meningeal PCNSL is treated with intrathecal methotrexate or cytosine arabinoside. Transliquoral seeding of PCNSL is frequent, distant metastases occurring in 6%-8%. Therapy of AIDS-related PCNSL makes use of radiation and corticosteroids, and rarely of chemotherapy. The pathogenesis of PCNSL is unknown, but Epstein-Barr virus may be a contributory factor.

Total Circulating b Lymphocyte Abnormalities in a Primary Cerebral Localization of Non-Hodgkin Lymphoma: A Case Report

The authors describe a case of primary central nervous system lymphoma In a 43-year-old male. Interest in this rare form of B-lymphocyte non-Hodgkin's lymphoma is due to its increasing incidence in the last decade, especially in immunodeficient patients. Extraneural involvement was excluded by staging examinations: bilateral bone marrow biopsy from the posterior iliac crest, bipedal lymphography, abdominal CT scan, skeletal, thoracic and gastrointestinal X-rays, spinal puncture, ORL and clinical examination. The peripheral immunologic state was particularly interesting: there was a substantial decrease in total circulating B-lymphocytes at diagnosis (4.4 % = 80/mmc; nv 13 ± 4 % = 287 ± 130/mmc) and a further decrease after 2 and 4 months of therapy (0.16% = 2/mmc). Three months after completion of therapy, the B-lymphocyte level returned to the base level at diagnosis (7 % = 88/mmc). At 10 months after diagnosis and 3 months after completion of chemotherapy, the patient is alive and in good health except for the after-effects of a left hemiparesis. The etiologic and possible pathogenic factors are considered.

Stereotactic biopsy diagnosis of primary non-Hodgkin's lymphoma of the central nervous system. A histological and immunohistochemical study

We report 29 cases of primary non-Hodgkin lymphomas (NHL) of the Central Nervous System (CNS), 26 of which were diagnosed by stereotactic biopsy and 3 by autopsy. In seven cases the patients were affected by AIDS. Histological examination of this series revealed 15 cases of immunoblastic lymphoma, 12 cases of centroblastic lymphoma, 1 case of lymphoplasmacytic immunocytoma and 1 case of unclassified high grade lymphoma. By immunohistochemistry the B-cell origin of lymphoma cells was demonstrated in 28/29 cases. Eight cases were assigned to the B-cell lineage by demonstration of monotypic surface or cytoplasmic immunoglobulin or of the B-cell phenotype CD22+, CD2-, CD3-, CD5-. In twenty cases the B-cell nature of lymphoma was identified by positivity with two or more anti-B monoclonal antibodies (LN1LN2MB2) and negativity by the anti-T monoclonal antibody UCHL1. The histologically unclassified case was a peripheral T-NHL (CD1-, CD2+, CD3-, CD5+, CD22-). We conclude that histological and immunohistological evaluation of stereotactic biopsy specimens provides sufficient information for diagnosis and phenotypic characterization of primary NHL of the CNS. These lymphomas exhibit important predominance of high-grade malignancy histological types and are nearly always B-cell derived. In addition, we provide further evidence that the panel of monoclonal antibodies LN1, LN2, MB2, and UCHL1 is useful for immunophenotypic characterization of brain lymphomas when only paraffin embedded stereotactic biopsy tissue is available.

Diagnosis of primary cerebral lymphoma with particular reference to CT-guided stereotactic biopsy

In establishing the histological diagnosis of primary cerebral lymphoma, stereotactic brain tumour biopsy is the method of choice as the mainstay of therapy is radiation and chemotherapy. This study describes the histopathology and diagnostic immunohistochemistry of 54 primary brain lymphomas in a mainly non-AIDS population. The stereotactic biopsies were performed using the Leksell CT stereotactic frame and a spiral needle which procured about 10-mm-long tissue cylinders. Usually, three successive biopsy cylinders were taken along the target trajectory. Histological examination revealed the prevalence of high-grade non-Hodgkin's lymphoma of the polymorphous centroblastic type. The series did not include any low-grade lymphomas or T-cell lymphomas. L-26 immunohistochemistry resulted in a positive staining of the blasts, thus confirming the B-cell origin of primary brain lymphomas. Small reactive T-lymphocytes and monohistiocytic cells were also found within and at the periphery of the lymphomas and in areas of degeneration. In the biopsies of nine patients, who had shown significant reduction of the lesions on the CT scans, after corticosteroid medication, regressive tissue changes were predominant and consisted of T-lymphocytes, macrophages, and occasionally bizarre reactive astrocytes.

Primary central nervous system lymphoma

Primary central nervous system lymphomas constitute less than 2% of primary brain tumors. Although their cause is unknown, they are in some way related to immunosuppression. The typical patient is a middle-aged man who displays the syndrome of a subacute mass lesion. These tumors most commonly occur as a single, bulky mass in the hemispheric white matter or the deep gray matter, but multiple tumors occur in approximately a fourth of the patients. The findings on computed tomography are distinctive and nearly pathognomonic. The majority of these tumors are B-cell lymphomas with aggressive histologic changes. Surgical intervention should be reserved for tissue diagnosis because surgical removal does not seem to influence the outcome. Conventional therapy consists of whole-brain irradiation with or without chemotherapy. The prognosis for patients with such tumors is grim, the median duration of survival being less than 2 years with conventional therapy and the 5-year survival being less than 5%.

Non-Hodgkin's lymphoma involving the brain. Diagnostic usefulness of stereotactic needle biopsy in combination with paraffin-section immunohistochemistry

A stereotactic needle biopsy was examined for applicability in diagnosing brain non-Hodgkin's lymphoma (NHL), because the procedure is far less aggressive than biopsy by open surgery. Formalin-fixed materials including four stereotactic specimens were available from nine patients with brain NHL. In addition to routine histopathology and histochemistry, paraffin-section immunohistochemistry was performed using a panel of monoclonal antibodies suited to such sections. Although several histopathological features characteristic of brain NHL could not be evaluated in three of the four stereotactic specimens owing to the small size of the specimens and partial invasion by lymphoma cells, the lesions in all cases could be characterised by immunohistochemistry. Examination for cytoplasmic immunoglobulin (cIg) was also performed, but specific identification of cIg was difficult in five cases because of diffuse background staining and passive diffusion of plasma protein into the cells during tissue processing. A review of the literature indicates the technical difficulty in cIg staining, since the incidence of cIg-positive cases in an individual study varied considerably, and lymphoma cells in 15 of 128 cIg-positive brain NHL cases have been reported to possess both light chains. From these findings, together with the relative difficulty in obtaining fresh tissues for study, it is concluded that, when the specimens are to be examined by paraffin-section immunohistochemistry using the above monoclonal antibodies, stereotactic needle biopsy is a useful, less aggressive method for diagnosing brain NHL.