Computed tomography in primary reticulum cell sarcoma of the brain

The Role of Radiation Therapy in the Management of Primary Non-Hodgkin Lymphomas of the Central Nervous System: Clinical Study of 10 Cases

A series of 10 patients with a primary non-Hodgkin lymphoma of the central nervous system were observed and treated by the authors. All were diagnosed after a pathologic examination of the surgical material; the lesions were supratentorial in all cases and unifocal in 9. In every case radiation therapy improved clinical conditions and in most cases even radiologic features of the patients. Four patients were alive and without evidence of disease many months after therapy. Four patients died with a relapse in the central nervous system; 3 of them had disseminated disease at the time of death. Two patients died for an unknown cause. Radiation therapy was performed with 60Co source with 2 opposed portals and the whole brain irradiation technique in all cases but 2. Doses ranged from 35 to 54 Gy. The recent literature on this uncommon disease and the most adequate therapeutic possibilities of radiation therapy and chemotherapy, or both, are discussed.

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

The clinico-pathologic data of 37 primary lymphomas of the brain were retrospectively reviewed. The tumors were classified according to the Kiel classification and the Working Formulation System. They represented 1.02% of all primary intracranial tumors of our series. The radiologic prediction appeared to be difficult: the suspicion was maximal when the absence of pathologic vessels at angiography occurred in a meningioma-like lesion at CT. Median survival was 4.53 months in the 16 cases who underwent surgery only versus 25.7 months in the 8 cases operated and irradiated with 40-60 Gy (p < 0.01). The prognosis of lymphomas of the CNS, even if radioresponsive tumors, remains poor. Most patients relapse after treatment, most often locally in the brain, with a variable frequency of spinal or systemic localization.

Imaging in primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) accounts for approximately 3% of all primary CNS tumors. Congenital or acquired immunodeficiency is the only established risk factor for PCNSL. Rates decreased slightly in the mid-1990s, concordantly with the decreasing rates of AIDS. However, the incidence has been increasing in the elderly immunocompetent population, and this trend seems to be independent of improvements in diagnostic techniques, and of overall trends in the incidence of brain tumors and systemic lymphomas. This study presents our experience with the imaging features of PCNSL. Computed tomography (CT) and magnetic resonance imaging (MRI) findings were reviewed in a series of 38 cases of pathologically proven PCNSL. The incidence rate of PCNSL was higher in men than in women (58% versus 42%). Mean age at presentation was 63 years; 120 lesions were demonstrated in the 38 patients, with a 53% frequency of tumor multiplicity. Both CT and MR mainly showed solitary or multiple well-defined round or oval-shaped mass lesions, typically hyperdense on unenhanced CT scans, iso to hypointense on T2 MR weighted images. These lesions also showed an increased signal intensity on diffusion-weighted images. Virtually all lesions enhanced after intravenous administration of contrastmedium. On (1)H-magnetic resonance spectroscopy ((1)H-MRS) most lesions presented increased Cho/Cr, Cho/NAA and lactate/Cr ratios when compared to normal gray matter. No changes in the imaging presentation have occurred over the past two decades, apart from lesions now being smaller at diagnosis. Our imaging findings are in agreement with the existing literature data and with the reported increasing trend of multifocal tumors. Our epidemiologic results add value to the existing evidence of increasing incidence rates among the immunocompetent elderly population.

Imaging of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an aggressive neoplastic process that occurs in both immunocompetent and immunocompromised patients. Over the past 30 years there has been a steady increase in the number of cases in both patient populations. The imaging features for the disease and demographic characteristics within these patient populations vary, and in this article the authors describe the salient features of these two groups.

Characterization of primary intracranial lymphoma by computed tomography: an analysis of 36 cases and a review of the literature with particular reference to calcification haemorrhage and cyst formation

Previous published series describing the appearances of primary central nervous system lymphoma (PCNSL) state that calcification, haemorrhage and cyst formation are rare, but generally fail to quantify or expand on this statement. We present the pre-treatment computed tomography (CT) findings of 36 patients with biopsy proven PCNSL. In this series, calcification was present in only one very atypical lesion and evidence of haemorrhage was not seen. Small intralesional cysts were present in four of the total of 50 lesions. PCNSL usually appeared as one or more well defined focal lesions, iso- or hyperdense to grey matter, with homogeneous enhancement following IV contrast injection. Less commonly the contrast enhancement was inhomogeneous, only one lesion failed to enhance. Disproportionately little oedema and mass effect compared with lesion size was noted on approximately half the CTs. Lesions usually touch either the ependymal lining of the ventricles or the leptomeningeal surface.

Correlation of computed tomography with the histopathology of primary malignant lymphoma of the brain

The authors present seven autopsy cases of non-AIDS primary malignant lymphoma of the central nervous system to correlate the pathology with the findings of the most recent pre-mortem computed tomogram (CT). Of 10 primary contrast-enhancing (CE) lesions treated by chemotherapy alone, radiotherapy alone, radiochemotherapy, or surgery combined with radiochemotherapy, all but one completely disappeared after the initial course of therapy. However, in six of the seven patients, the final pre-mortem CT demonstrated CE lesions. In three cases CE lesions were at the same site as the primary lesion, in one case in a remote location, and in two cases in diffuse and multiple locations. In all but one case these CE lesions corresponded histologically to tumor nodules or to white matter densely infiltrated by tumor cells. The sole exception was diagnosed pathologically as delayed radiation necrosis. The final CT also showed five low-density areas (LDAs) which had evolved from CE lesions after the completion of therapy. These LDAs corresponded to rarefied or necrotic parenchyma in which tumor cells remained, mainly in the perivascular spaces. One case exhibited diffuse tumor infiltration of periventricular structures which appeared to have normal density and no CE on the final pre-mortem CT.

Primary cerebral lymphoma: report of 24 patients and review of the literature

A retrospective study of 24 patients with primary non-Hodgkin's cerebral lymphoma (non-immunocompromised) is presented. All patients were seen at the Royal Preston Hospital, Lancashire between 1976 and 1991. Fifteen patients were over the age of 50 years (range 27-84). The commonest clinical presentation, seen in 16 patients was of an expanding space-occupying lesion. The diagnosis was suspected from the radiological findings but confirmation in every case was by histological examination of biopsy or necropsy material. The tumours were treated either by surgical excision or by biopsy and radiotherapy. Chemotherapy was given in two patients. Despite these measures the mean survival time was 3.6 months. The clinical radiological and pathological features of these tumours are highlighted with particular emphasis on the use of stereotactic biopsy, immunohistochemistry and chemotherapy in diagnosis and treatment.

Primary intracranial lymphomas

We present 20 cases of primary intracranial lymphoma and review the most important published series on this subject. The clinical patterns and the differential diagnosis from other intracranial space-occupying lesions on the CT and angiographic evidence are discussed. Surgical treatment was given in 19 of our cases, followed in 17 cases by radiotherapy and in 4 by chemotherapy. One patient was treated by a ventriculo-peritoneal shunt. The effectiveness of the various modalities of treatment is discussed in the light of survival.

A case report of central nervous system lymphoma following immunosuppression

Lymphoma is a well recognised complication of immunosuppression. A case is presented of a patient who developed CNS lymphoma thirty-three months after renal transplantation. The incidence and characteristics of lymphoma developing post-transplantation and the treatment of central nervous system (CNS) lymphomas are discussed.

Prognostic factors in the diagnosis and treatment of primary central nervous system lymphoma

The authors describe the results of multimodality therapy in 27 patients with biopsy-proven primary central nervous system (CNS) lymphoma treated between 1976 and 1986. Treatment included surgical resection (15 patients), radiotherapy (27 patients), and chemotherapy (nine patients). Actuarial survival rates for the 27 patients at 1, 2, and 5 years after diagnosis were 70%, 54%, and 45%, respectively. Nine patients were recurrence-free at 8 to 106 months follow-up. A multivariate risk analysis identified five factors which had a favorable impact on survival: (1) age less than 60 years (P less than 0.02); (2) preoperative Karnofsky performance score greater than or equal to 70 (P less than 0.02); (3) presence of strictly hemispheric tumor (P less than 0.0003); (4) whole-brain radiation dose between 4000 and 5000 cGy (P less than 0.05); and (5) addition of chemotherapy to radiotherapy (P less than 0.002). Patients with complete tumor resolution on computed tomography 6 months after beginning treatment also had longer survival (P less than 0.01). The presence of malignant cells on cerebrospinal fluid cytologic examination correlated with an increased risk of distant metastasis (P less than 0.05). In those patients whose disease eventually recurred, the administration of an additional therapeutic modality significantly increased the length of postrecurrence survival (P less than 0.05). Although surgical resection provided no increase in survival, the addition of chemotherapy to postoperative cranial irradiation significantly enhanced the duration of survival. Our experience suggests that pretreatment clinical and diagnostic factors can help in predicting survival and in planning treatment.

Primary chiasmatic lymphoma

We report a case of primary cerebral lymphoma in an unusual site, the chiasma, and with a unique combination of symptoms. We review the salient published data on lymphomas in this site.

Increasing incidence of primary brain lymphoma in the US

There have been a number of clinical reports suggesting an increasing incidence of primary brain lymphoma unrelated to acquired immune deficiency syndrome (AIDS) and organ transplantation. To investigate this issue, the US incidence of this rare lymphoma was assessed using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program (1973 through 1984). Never-married men, a relatively high risk group for AIDS, were excluded from the analyses. Brain lymphoma incidence increased from 2.7 in 1973 through 1975 to 7.5 cases per ten million population in 1982 through 1984 (chi-square trend, 15.25; P less than 0.001), and it increased among both men (chi-square trend, 6.74; P = 0.009) and women (chi-square trend, 10.48; P = 0.001). Increases in incidence also were observed among persons younger than 60 years of age (chi-square trend, 4.10; P = 0.04) and persons 60 years of age and older (chi-square trend, 9.16; P = 0.002). This increased incidence of brain lymphoma appears to be real: It antedates the AIDS epidemic and does not appear to be related to organ transplantation, another cause of increased risk of brain lymphoma. Although part of the increase may be an artifact of improvements in diagnostic technology and practice, most of the observed increase antedates the widespread use of such technologies. Finally, the increase in incidence of brain lymphoma does not appear to be related to overall trends in the incidence of brain tumors and non-Hodgkin's lymphoma, and it is not related to time trends in nosology.

Primary central nervous system lymphoma

Primary lymphoma of the central nervous system (CNS), including reticulum cell sarcoma, microglioma, and histiocytic lymphoma, represents less than 1% of all primary brain tumors. In the last 10 years, this tumor has tripled in frequency in the nonimmunosuppressed population. By 1991, the tumor will be the most common neurological neoplasm by virtue of the increase in sporadic occurrence and in the acquired immunodeficiency syndrome (AIDS) population. Three percent of AIDS patients will develop this tumor either prior to AIDS diagnosis or during their subsequent course. In addition to acquired immunosuppression, patients with inherited disorders (such as Wiskott-Aldrich syndrome, severe combined immunodeficiency, and X-linked immunodeficiency) and other acquired disorders of the immune system are predisposed to the development of CNS lymphoma. Immunological studies have suggested a role for Epstein-Barr virus in the production of this tumor. Although subtypes exist, non-Hodgkin's lymphoma of the CNS most commonly consists of histiocytic cells or large immunoblastic cells bearing B cell surface markers in close proximity to the lateral and third ventricles. Sixty percent of these deposits are multiple, and subarachnoid invasion is seen in one-quarter of patients. Vitreous involvement of the eye occurring prior to and during the course of CNS lymphoma has been noted in up to 25% of patients. The involvement of multiple areas of the neuraxis, the eye, and multiple intracranial sites often occurs in the absence of obvious systemic lymphoma. Therapeutic trials of brain radiation therapy are associated with median survivals of less than 1 year. Uniform complete responses of intracranial deposits are recorded following chemotherapy with high-dose intravenous methotrexate, CHOP (cyclophosphamide, hydroxydaunomycin/doxorubicin, Oncovin (vincristine), and prednisone), high-dose cytosine arabinoside, and intra-arterial methotrexate with barrier modification.

Primary lymphoma of the central nervous system: experience at Addenbrooke's Hospital, Cambridge

A series of 22 cases of primary intercerebral lymphoma are reported. The clinical presentation and natural history were similar to high grade glioma in adults. There was a male to female ratio of 2.7:1, and a mean age at presentation of 63 years (range 47-72 years). Single masses were present in 77%, and the frontal lobe was the most frequently involved (64%). Treatment regimes included varying combinations of surgical resection and cranial irradiation. Sixteen patients have died, twelve due to recurrent or persistent intracerebral disease. The median survival was ten months. Six patients are still alive at 52, 12, 10, 9, 6 and 4 months. Failure to control the intracranial tumours was the main cause of death. Significant debulking of the tumour was the single most important prognostic factor, although a good initial response to steroids was also favourable. No patient developed spinal deposits. Even when there is a good response to radiation and prolonged survival, the quality of life may be poor: in this series only five out of 22 patients (23%) returned to a normal life. Radiation dosage and the indications for spinal treatment are discussed.

Primary CNS lymphoma presenting as a choreic movement disorder followed by segmental dystonia

Clinical presentation of primary CNS lymphoma with an extrapyramidal movement disorder has not been recorded. A 66-year-old woman presented with chorea involving her left arm and subsequently developed right-sided segmental dystonia with prominent hemifacial dystonic spasms, milder torticollis and dystonia of the right arm. Investigations revealed primary CNS lymphoma with extensive involvement of the right-sided basal ganglia as well as lesions confined to the head of the left caudate nucleus and the corpus callosum. Chorea of her left arm subsided with progressing disease while remission of right-sided segmental dystonia was observed following radiotherapy of the brain. This patient's findings and a review of the literature suggest a possible relation between cranio-cervical dystonia and pathology affecting the head of the caudate nucleus.

Limbic lymphoma

Two cases of metastatic malignant lymphoma confined to the limbic-hypothalamic region are presented. The non-specific nature of the neurological symptoms associated with these lesions such as memory loss, impotence and confusion made neurological localization of the disease process difficult. While non-contrast computed tomography (CT) was unremarkable, contrast CT was diagnostic, showing bilateral homogenous enhancement of specific limbic-hypothalamic structures without significant mass effect. Since lymphomatous involvement of the limbic-hypothalamic area tends to be infiltrative without attendant mass effect, detection of metastasis may be elusive unless special attention is directed to this region. As lymphoma is often chemoresponsive and highly radiosensitive, early recognition of limbic-hypothalamic involvement of this disease is important.

Primary cerebral lymphoma presenting as steroid-responsive chiasmal syndrome

A case of multiple primary cerebral lymphoma presenting with bitemporal hemianopsia due to a large suprasellar lesion is described; the visual symptoms improved after corticosteroid treatment. Involvement of the optic pathways is very unusual in primary central nervous system lymphomas; the visual symptoms can be due to lymphomatous uveitis or to infiltration of the optic nerves by leptomeningeal lymphoma, whereas bitemporal hemianopsia due to chiasmal compression has not been reported as first symptom of a cerebral lymphoma. The CT finding of multiple hyperdense well-enhanced lesions and their symmetrical distribution in the basal ganglia and frontal horns suggest the diagnosis of lymphoma. Improvement of neurological deficits during corticosteroid treatment is another feature typical of cerebral lymphomas.

Primary malignant lymphoma of the central nervous system. Results of treatment of 11 cases and review of the literature

Eleven patients with primary malignant lymphoma of the central nervous system (CNS) were treated at the Medical College of Wisconsin Affiliated Hospitals between 1964 and 1984. Three patients had a prior history of immunosuppressive therapy following renal transplantation. All patients had biopsy-proven disease and 10 of the 11 were treated with external radiation therapy. The doses to the primary tumor ranged from 34 to 59.4 Gray (Gy). Actuarial (life-table) survival rate was 82% at 1 year and 43% at 3 years. No recurrence was seen after 13 months. Eighty-six reports totaling 693 cases of primary malignant lymphoma of the CNS were found in the literature. Of these, 308 cases were treated with a combination of surgery and irradiation. Overall survival at 5 years for those patients who received more than 50 Gy compared with less than 50 Gy to the primary tumor was 42.3% versus 12.8% (p less than 0.05). Twenty-one patients survived longer than 5 years. Late relapse was notable, with 10 (47.6%) of 21 tumors recurring between 5 and 12.5 years after diagnosis. Based on this review, a minimum of 50 Gy radiation to the primary tumor is recommended. While no statement regarding the efficacy of craniospinal irradiation or chemotherapy can be made in view of the small numbers, the use of craniospinal irradiation and/or systemic chemotherapy should be considered for future trials.

Intracranial malignant lymphoma. Report of 30 cases and review of the literature

Although primary malignant lymphoma is a rare entity in the gamut of intracranial tumors, it is more frequently seen than the secondary intracranial spread of a primary extracranial lymphoma. In general, the occurrence of lymphomas seems to be provoked by immunosuppression, as with medication (predominantly after transplantation) or with immunodepressive disease such as acquired immunodeficiency syndrome (AIDS). The usual age of onset of this disease is 55 to 65 years; and the male:female patient distribution is roughly 2:1. Characteristically, computerized tomography (CT) scans of lymphomas show a mass which is often large with regular contours, moderate mass effect, and hyper- or isodensity with marked and often homogeneous enhancement. In the series of 30 patients reported, the locations of lesions, in order of decreasing frequency, were the frontocallosal and temporal regions, the basal ganglia, and the cerebellum. Multiple lesions were present in 15% of these cases (20% to 40% in the literature). The following features should raise the suspicion of intracranial lymphoma: mirror lesions of the basal ganglia, bilateral subependymal infiltration, and leptomeningeal involvement contiguous with an intracerebral mass. According to the literature, the angiographic finding typical of lymphoma is an avascular tumor. A blush or vascular encasement of the mass seems to be rare, and the present series was in accordance with other reports in this respect. Differential diagnostic consideration should include meningioma, glioblastoma, metastatic disease, and focal infectious lesions such as toxoplasmosis or multifocal progressive leukoencephalitis, particularly in immunodepressed subjects. Diagnosing lymphoma from CT scans offers the alternative of substituting stereotaxic biopsy and neuropathological diagnosis for the more aggressive open surgical approach, since radiation therapy and possibly chemotherapy usually prove to be the treatment of choice.

Primary lymphoma of the central nervous system: a clinicopathologic analysis of 26 cases

We analyzed 26 cases of primary lymphoma of the central nervous system. There were 14 males and 12 females ranging in age from 5-76 years (median age 51 years, mean age 50.2 years). None had received organ transplantation or immunosuppressive therapy. The most common presenting symptoms were headache, mental changes, nausea, vomiting, and convulsions. The main neurological findings were hemiparesis, papilledema, visual field defects, and cranial nerve palsies. The most common finding in the cerebrospinal fluid (CSF) was high protein content; CSF cytology was positive in only one case. Computerized tomography was done in 14 cases; all showed a contrast-enhancing lesion. Angiography generally revealed an avascular mass. The most common location above tentorium was the frontal lobe; in four cases the tumor was infratentorial (cerebellum, 3 cases). In five cases there was diffuse involvement of the brain; all had severe dementia and diagnosis was not made until the autopsy. Histologically, the most common type was diffuse histiocytic or immunoblastic lymphoma according to Rappaport and the Working Formulation classification respectively. Radiation therapy alone in five patients gave a median survival of 17 months. Five patients received radiation and chemotherapy, and median survival was 16 months. Two patients developed ocular lymphoma 8 and 36 months later that was treated by radiation.

Steroid-induced regression of primary malignant lymphoma of the brain

A case of primary malignant lymphoma involving the splenium of the corpus callosum is reported in a 54-year-old woman presenting with symptoms of increased intracranial pressure. In view of the prominent cerebral edema associated with the intracranial lymphoma, dexamethasone was initiated at a daily dosage of 8 mg by intravenous administration. Computed tomography scans obtained 10 days after admission revealed dramatic regression of the lesion which corresponded with clinical remission. Steroid-induced regression of primary malignant lymphoma of the brain as evidenced by computed tomography is reviewed in the literature, and the role of corticosteroids is discussed.

Intracranial histiocytosis X: a case report

A case of intracranial histiocytosis X that presented radiologically with thickening of the pituitary stalk is presented. The radiologic findings, including a blush seen on angiography, are described.

Primary lymphoma of the central nervous system: Manitoba experience and literature review

We describe eight cases of primary cerebral lymphoma seen in Manitoba from 1980 to 1985. The clinical presentation is similar to other primary brain tumors. The diagnosis should be considered when single or multiple, often deep lesions, show dense enhancement on computerized tomographic (CT) scan, but are avascular at angiography. These tumors are histologically indistinguishable from non-Hodgkins lymphomas arising outside the CNS. The prognosis is poor. However, radiotherapy with or without surgery may offer significant palliation. Although there is no consensus on the value of chemotherapy, corticosteroids alone or multiagent chemotherapy have shown promise in a few cases. For these reasons, histologic diagnosis should be sought in all cases and surgery, radiotherapy, and chemotherapy should be considered, as prolonged survival is possible.

Diagnosis of a primary non-Hodgkin's lymphoma of the central nervous system by examination of the cerebrospinal fluid

This paper is a report on a case of primary Non-Hodgkin's lymphoma of the central nervous system, diagnosed by cytological and immunological examination of the cerebrospinal fluid. The relevant literature on the subject is reviewed. The importance of examination of the cerebrospinal fluid in cases suspected of this disease is stressed.

Radiation therapy of primary malignant lymphoma of the brain

Primary malignant lymphoma of the brain (PMLB) is uncommon. Between 1975 and 1982, the authors observed 11 patients with histologically confirmed PMLB. Mean survival after radiation therapy was 7 months with 5 patients surviving for more than 2 years. Multifocal lesions were seen in 9 patients and spontaneous regression was seen at computed tomography in 2 patients. Radiation doses in excess of 30 Gy controlled the primary tumor, but intracranial recurrences occurred even after whole brain irradiation to 40 Gy. Only one patient had a relapse outside the central nervous system, and none had clinical evidence of seeding to the spinal canal. The authors postulate that PMLB usually is a multifocal intracranial disease, and that whole brain irradiation of at least 30 to 40 Gy should be given to all patients with this disease.

Primary central nervous system lymphoma

A retrospective analysis of 21 cases of primary central nervous system (CNS) lymphoma is reported. All patients presented with a solitary mass in the supratentorial region. None had previously received immunosuppressive therapy. Neuroradiological studies included technetium-99m-pertechnetate brain scanning in eight cases, cerebral arteriography in all 21 cases, and computerized tomography (CT) in 14 cases. The characteristic features were increased uptake in brain scans, mass effect in arteriograms, and marked contrast enhancement on CT scans. Abnormal tumor vessels were occasionally seen on arteriography, and subtraction films were usually required to appreciate tumor stain. All patients underwent craniotomy, and histological studies of the tumors showed a diffuse type of lymphoma in all cases. Immunoglobulin testing was performed in 19 cases and a monoclonal spike was verified in 10, suggesting a B cell origin. All patients were followed until their death except one who was still alive 12 months from onset of symptoms. Therapy included subtotal resection in all 21 cases, whole-brain irradiation in six cases, chemotherapy in two cases, and a combination of whole-brain irradiation and chemotherapy in nine cases. Three different forms of chemotherapy were used. The results suggest that chemotherapy is an important addition to subtotal resection and whole-brain irradiation in the treatment of primary CNS lymphoma.

Primary intracranial lymphomas

We reviewed the cases of 16 patients with primary intracranial lymphomas. The clinical and radiological data proved to be helpful in suggesting the diagnosis, but only tumoral biopsy provided unequivocal diagnosis. In our cases radiotherapy proved to be the most effective treatment.

Computed tomography in primary lymphoma of the brain

C.T. scans of 19 patients with histologically proved primary lymphoma of the brain were reviewed and divided into three groups: solitary tumors (58%), multifocal tumors (31,5%), diffuse involvement of the brain (10,5%). The C.T. differential diagnosis are manifold, including meningioma, glioma, metastases, progressive multifocal leukoencephalopathy. Arteriography is not specific, but, correlation with C.T. results may suggest the correct diagnosis and encourage biopsy. The radiosensitivity of primary lymphoma of the brain emphasizes, the importance of an early diagnosis.

Primary lymphoma of the brain: a case report and review of the literature

A case of primary lymphoma of the brain is presented. The disease is rare and thus firm guidelines for therapy are lacking. Whole-brain irradiation therapy, the accepted treatment of choice, when given to a dose of 5000 rads, is associated with improved survival. However, the overall prognosis is poor due to local recurrence in the central nervous system and the tumor's ability to diffusely infiltrate the meninges. Twenty-six percent of the cases may have positive cerebrospinal fluid cytology. Whether the addition of intrathecal chemotherapy with agents such as methotrexate will improve upon the results obtained with irradiation therapy alone would be an appropriate subject for a cooperative prospective randomized study.

Computed tomography of malignant lymphoma of the brain

Correct diagnosis of malignant lymphoma of the brain and differentiation from malignant glioma, metastases, meningeoma and infection is often difficult. With the aim of finding characteristics pointing to the correct diagnosis all CT examinations from 16 patients with primary or secondary lymphoma of the brain were analysed. In 3 of 10 patients with primary lymphoma and 4 of 6 with secondary lymphoma the tumors were multiple. No differences between the CT appearance of primary and secondary lymphoma were found except that secondary lymphomas were generally smaller and more often multiple. The lymphomas were most often well demarcated, had a density equal to or slightly higher than normal brain tissue, were surrounded by no or slight edema and showed a moderate to marked contrast enhancement. The tumors were situated in the basal ganglia, corpus callosum or cerebellum in high frequency and were always in contact with either the ependyma of the ventricles or the superficial subarachnoid space. A tumor with widespread infiltration of the surroundings of the ventricles seen in 6 patients in the material is highly characteristic of lymphoma.

Primary lymphoma of the central nervous system. Clinicopathological study of experience at Stanford

The authors present 22 cases of primary lymphoma of the central nervous system (CNS) from Stanford University Medical Center. Fifteen other published series comprising 400 patients with this disease are also reviewed. Males were affected more often than females. The majority of patients were in the sixth decade of life. The most common presenting symptoms were headache, nausea, vomiting, and mental status changes. The most common presenting signs were hemiparesis and papilledema. An elevated protein concentration was the most common cerebrospinal fluid (CSF) abnormality. The CSF cytology was rarely positive prior to surgery. If a mass was seen on computerized tomography, it always enhanced with infusion of contrast material. On angiography, the tumor was generally seen as an avascular mass. The most and least common sites of involvement supratentorially were the frontal and occipital lobes, respectively. Infratentorially, the cerebellum was most often involved. Histologically, the most common tissue type according to the Rappaport and Working Formulation systems were diffuse histiocytic lymphoma and immunoblastic lymphoma, respectively. Therapy primarily involved surgery for biopsy or subtotal resection and radiation therapy. The majority of patients died, and the median survival time of those dying was distinctly shorter than the follow-up period of those patients still alive. This difference in survival time suggests that primary CNS lymphoma consists of more than one disease group. Statistical analysis of our series showed those patients with either a diffuse mixed lymphoma histology or an infratentorial location of disease had a poorer prognosis. These two factors cannot totally account for the division of cases into separate survival-related groups.

Primary lymphoma of the central nervous system. Computerized tomography scan characteristics and treatment results for 12 cases

A retrospective analysis of 12 patients with primary central nervous system non-Hodgkin's lymphoma seen from 1958 to 1980 was carried out with emphasis on diagnostic evaluation and treatment results. Computerized tomography (CT) scans were found to be the most valuable diagnostic tool both for initial evaluation as well as follow-up. Characteristic CT scan features were identified and are discussed. Three patients had a history of previous immunosuppression; two had preceding and concurrent uveitis. Nine of the 12 patients were treated primarily with radiation therapy. Three patients were diagnosed at autopsy and had not received definitive therapy. Size of lesion proved to be the most important prognostic factor and appeared to be related to location. Gross total excision of tumor did not appear to improve survival. Two patients were alive with no evidence of disease at 38 and 48 months, respectively. Recurrences were noted from 1 to 33 months after diagnosis (median, 14 months), suggesting the advisability of long-term follow-up prior to presumption of cure. From these results and a review of the literature, possible treatment approaches are presented.

Microglioma--unusual computed tomographic appearance and course of neoplasm

Microglioma accounts for 0.8-1.5% of primary brain tumors. Eight cases of primary lymphoma of brain are presented. 50% of the patients demonstrated unusual computed tomographic appearances. These patients were divided into three groups depending on clinical outcome. Survival seems to be related to treatment modality. Longest survival times were in patients treated with radiation alone or radiation following biopsy.

Primary non-Hodgkin's lymphoma of the central nervous system. Results of radiotherapy in 15 cases

Primary non-Hodgkin's lymphoma (NHL) of the central nervous system is a rare disease. The number of cases reported in the literature does not exceed 200. The current series comprises 15 cases of primary NHL of the CNS. In 12 cases material for pathology was obtained at surgery. In the other three cases the diagnosis was established by cytologic examination of the cerebrospinal fluid (CSF). The type of lymphoma was predominantly the diffuse lymphocytic type. All the patients received irradiation on the whole brain by means of two opposite lateral fields. The administered total doses were 40 Gy in four weeks in ten cases, 50 to 60 Gy in 5 to 6 weeks in four cases and 30 Gy in three weeks in one case. All but three patients are dead although initially a good tumor response was obtained as confirmed in most of the cases by CT scan. The mean survival of the dead patients was 14.5 months. No relationship was found between the administered dose and the relapse-free time. In six cases (40%) evidence of seeding was observed. Because of the poor results obtained with irradiation either of only the tumor bearing area or whole brain and because of the high risk of seeding through the CSF, the irradiation of the entire CNS is recommended in patients with primary NHL of the brain.

Solitary metastasis of systemic malignant lymphoma to the cerebellopontine angle

Systemic malignant lymphoma rarely produces solitary metastasis to the brain. We report such a case in the cerebellopontine (CP) angle mimicking an acoustic neurinoma. CT scan showed a large, round mass in the CP angle which enhanced homogeneously following contrast infusion. The internal auditory meatus appeared to be eroded. The clinical, radiological, and pathological findings are presented.

Cerebral lymphoma: clinical radiological correlation

Twenty patients with primary malignant lymphoma of the brain are described. This tumour tends to involve deep, central structures with subependymal spread and there is a high incidence (30%) of multifocal disease. Many cases present a clinical picture suggesting the location and by inference the possible nature of the tumour: early mental change, somnolence and headache are prominent. In the case of a solitary lymphoma, the computed tomographic appearance is sometimes similar to that of a meningioma whereas, in multifocal disease, confusion with metastases is almost invariable. With CT, it should be possible to reduce the frequency of misdiagnosis, and thus avoid overlooking a potentially radiosensitive lesion.