it is an uncommon glial neoplasm of astrocytic origin that occurs in adults and is exceedingly rare in children . it is classified as grade iii astrocytoma according to 2007 world health organization classification of central nervous system ( cns ) tumors . different chemotherapeutic agents and radiotherapy regimens have been used , but the prognosis still remains poor . the available literature suggests age , male sex , performance scores at the presentation , and site of involvement in magnetic resonance imaging ( mri ) as the prognostic factors . the authors studied different prognostic factors and the outcomes with temozolomide and radiotherapy in six cases of gliomatosis cerebri treated at their institution from 2007 to 2012 . six patients treated at department of neurosurgery , nizam 's institute of medical science from july 2007 to february 2012 with a diagnosis of gliomatosis cerebri were included in the study . data were obtained by reviewing the admission case files , radiation oncology , radiology , and pathology records . the radiological criteria employed were widespread involvement of white matter with preservation of normal anatomical architecture in two or more lobes of the brain . all patients underwent clinical examination followed by mri brain plain and contrast imaging studies on admission . surgery was done in all patients . surgical plan varied based on the location of the tumor . since the tumor is of diffusely infiltrative nature , the aim of surgery in all patients was subtotal excision . postoperatively , 2 patients received concurrent chemoradiotherapy followed by adjuvant temozolomide , 2 patients received radiotherapy alone . a retrospective analysis was performed using the clinical charts , radiological investigations , and pathological examinations . age of the patients at diagnosis ranged from 16 to 60 years , with mean age was 41.3 years , median age was 42 years . the range of karnofsky score at the time of presentation was 3090 . presenting symptoms included headache , seizures , and altered sensorium . examination findings included papilledema in two cases , cranioneuropathy in 4 patients , upper motor neuron type of facial palsy , impaired gait disturbances and impaired extraocular movements in 1 patient each . the summary of details of the six patients included in the study all 6 patients underwent computed tomography ( ct ) and mri of the brain . ct showed poorly defined low - density lesions in four cases . in two cases , ct revealed obliteration of lateral ventricle and basal cisterns with midline shift suggestive of increased intracranial pressure . mri t1- and t2-sequences showed temporo - parietal lobes involvement predominantly with temporal lobe involvement seen in 4 patients , parietal lobe involvement in three , and frontal lobe involvement in 2 patients [ figure 1 ] . contrast enhancement is hardly seen with only two cases showing mild patchy enhancement of areas corresponding to the hyperintense areas on t2-sequence . ( b ) t2-weighted magnetic resonance imaging showed an area of diffuse poorly defined high signal intensity with a variable degree of obliteration of sulci and gyri . ( c ) contrast magnetic resonance imaging shows mild diffuse patchy enhancement the histology from resected specimens was essentially similar . the cells were small with elongated nuclei ; the cytoplasm was scant to moderate with few gemistocytes . the mitosis was few ; the ki67 ranged from 3% to 10% and gfap was positive in all cases [ figure 3 ] . ( a ) h and e 10 diffusely infiltrating small round to oval cells with pleomorphic nuclei . ( b ) h and e 40 gemistocytic astrocytes and scattered mitotic figures immunohistochemistry of tumour cells showing gfap positivity , ki 67 labelling index- 40% all 6 patients underwent surgery as the primary modality of treatment . emergency decompression was done in 1 patient due to sudden deterioration of glasgow coma scale . adjuvant radiotherapy protocol consisted of radiotherapy to preoperative t2 fluid - attenuated inversion recovery ( flair ) edema with margin to a total dose of 60 gy , 2 gy per fraction , and 30 fractions . concurrent chemotherapy was given with temozolomide 75 mg / m followed by adjuvant temozolomide 150 mg / m every 28 days for 6 cycles . postoperative concurrent chemoradiotherapy , followed by adjuvant chemotherapy was given in two cases ; radiotherapy only was given in two cases . one patient developed subacute intestinal obstruction , renal failure , discontinued radiotherapy and expired after 2 months ( case 1 ) , another patient survived 3 years , and 2 patients improved symptomatically and are on follow - up . two patients with poor karnofsky performance scale score did not receive adjuvant treatment and survived 2 months ( case 3 , 5 ) . two patients did not show progression at follow up of 2 years , overall survival ranged from 2 to 36 months , median overall survival was 4.5 months , mean overall survival was 18.5 months . ct showed poorly defined low - density lesions in four cases . in two cases , ct revealed obliteration of lateral ventricle and basal cisterns with midline shift suggestive of increased intracranial pressure . mri t1- and t2-sequences showed temporo - parietal lobes involvement predominantly with temporal lobe involvement seen in 4 patients , parietal lobe involvement in three , and frontal lobe involvement in 2 patients [ figure 1 ] . contrast enhancement is hardly seen with only two cases showing mild patchy enhancement of areas corresponding to the hyperintense areas on t2-sequence . ( b ) t2-weighted magnetic resonance imaging showed an area of diffuse poorly defined high signal intensity with a variable degree of obliteration of sulci and gyri . the cells were small with elongated nuclei ; the cytoplasm was scant to moderate with few gemistocytes . the mitosis was few ; the ki67 ranged from 3% to 10% and gfap was positive in all cases [ figure 3 ] . ( a ) h and e 10 diffusely infiltrating small round to oval cells with pleomorphic nuclei . ( b ) h and e 40 gemistocytic astrocytes and scattered mitotic figures immunohistochemistry of tumour cells showing gfap positivity , ki 67 labelling index- 40% emergency decompression was done in 1 patient due to sudden deterioration of glasgow coma scale . adjuvant radiotherapy protocol consisted of radiotherapy to preoperative t2 fluid - attenuated inversion recovery ( flair ) edema with margin to a total dose of 60 gy , 2 gy per fraction , and 30 fractions . concurrent chemotherapy was given with temozolomide 75 mg / m followed by adjuvant temozolomide 150 mg / m every 28 days for 6 cycles . postoperative concurrent chemoradiotherapy , followed by adjuvant chemotherapy was given in two cases ; radiotherapy only was given in two cases . one patient developed subacute intestinal obstruction , renal failure , discontinued radiotherapy and expired after 2 months ( case 1 ) , another patient survived 3 years , and 2 patients improved symptomatically and are on follow - up . two patients with poor karnofsky performance scale score did not receive adjuvant treatment and survived 2 months ( case 3 , 5 ) . two patients did not show progression at follow up of 2 years , overall survival ranged from 2 to 36 months , median overall survival was 4.5 months , mean overall survival was 18.5 months . gliomatosis cerebri is a rare brain tumor and it is often difficult to establish a definitive diagnosis . before the era of ct , the diagnosis of most reported cases of gliomatosis cerebri was based on autopsy findings . the classical diagnostic criteria proposed by scheinker and evans in 1943 were based upon autopsy findings of widespread infiltration of neoplastic glial cells . a diagnostic criterion proposed by kleihues et al . was the involvement of at least two lobes of the brain by small elongated cells without a cellular , centrally necrotic center . burger and schithaur defined gliomatosis cerebri as a diffuse infiltrating glioma , which may involve the supratentorial compartment , posterior fossa , or even intraspinal parenchyma , sometimes in continuity . male sex appears to be affected more in most of the series as is the case in our series also . the disease occurred in all age groups but was most common in the fifth decade with a second peak in the second decade similar to the trend seen in our limited series . clinical presentation is subtle and nonspecific , reflects the diffuse neuronal disruption caused by the disease manifesting as seizures , focal neurological deficits , memory loss , and other higher mental functions impairment . ct may either appear normal or shows subtle squashing of the ventricles or hypodensity or diffuse cerebral edema resulting in obliteration of the basal cisterns and midline shift . mri brain t2-weighted images and flair images show heterogenous hyperintensities appearing similar to cns infiammatory diseases , vasculitis , leukoencephalopathies or venous infarcts . nevertheless , a diagnosis of gc must be entertained in cases showing mri t2 and flair heterogenous hyperintensities with mass effect , loss of gray - white differentiation , and no uptake of contrast . the relative preservation of the blood - brain barrier is thought to be the reason for nonenhancement of contrast . in many instances , the diagnosis of gc has been delayed , because of the rarity and difficulty of diagnosis . histologically , tumor cells diffusely infiltrate white and gray matter and sometimes exhibited the perineuronal , perivascular or subpial tumor cell collections . the infiltrating cells showed variation from small cells with little cytoplasm to cells with moderate cytoplasm and the nuclei from elongated , oval to round . angiogenesis was absent in the gliomatosis cerebri , suggesting that tumor growth in these neoplasms is supported by coaptation of the existing vasculature and not by the formation of new vessels . the real pathological lesion demonstrated at autopsy is always wider than the lesion shown in mri or positron emission tomography . morphologically , tumors were identified as astrocytic , oligodendroglial , and mixed with astrocytic variety being common . oligodendroglial variant is more common in males and has a better prognosis while the astrocytic variant carries worst prognosis . median survival is least in astrocytic tumors around 11 months , and the oligodendroglial variant has survival up to 36 months . the study done by authors being retrospective with small sample size has inherent limitations in predicting and assessing the influence of various factors on survival . in our series , the median survival is 18.5 months , near to in the anocef database of 14.5 months . in our series , 3 patients with good performance score has survival ranging from 6 months to 36 months . poor performance scores at presentation have uniformly predicted bad prognosis even in the presence of favorable histology . the molecular basis is unknown , a number of reports demonstrated molecular alterations similar to those seen in common gliomas . these studies also suggested that gliomatosis cerebri seems to represent a monoclonal rather than a polyclonal process . presented 8 of 12 patients who received only radiation treatment ( median dose of 55.4 gy ) . the clinical and radiological findings improved in 3 patients , stabilized in 3 patients , and deteriorated in 2 patients . median survival was 11.4 months , and the authors concluded that radiation alone was not sufficient , and , therefore , more aggressive therapy may be needed . perkins et al . in their retrospective study of 30 patients concluded that rt is effective against gliomatosis cerebri . patients who are young and have a nonglioblastoma tumor of histologic subtype perform more favorably . though in the aforementioned studies , only radiotherapy alone was used , the authors expressed contradicting views regarding the radiotherapy as the only treatment modality . there are studies using chemotherapy as the only modalities showing comparable outcome with the series using radiotherapy only . having disease progression - free survival of 12 months concluded that temozolomide chemotherapy can be used initially , and radiotherapy can be deferred until the disease progression is documented taillibert et al . in their analysis of 296 individual cases including 90 patients followed through the anocef network , and 206 cases from the literature concluded that despite a high rate of stabilization , the survival impact of wbrt , which carries the risk of severe toxicity , remains unclear . from the current study , it can be observed that the good performance score at presentation definitely has a survival more than 6 months . surgical decompression with chemoradiotherapy only seem to have some effect in controlling the disease progression in patients having a good performance score at presentation does not seem to have affected the prognosis . apart from this , the nonglioblastoma type histology coupled with good performance scores at presentation seems to have favorable outcomes . the glomatosis cerebri , an aggressive tumor with a resemblance to many neurological diseases at presentation . adjuvant radiotherapy and chemotherapy and nonglioblastoma type histology seem to have favorable outcomes only in cases presenting with a good performance score at presentation
background : gliomatosis cerebri is characterized by diffuse infiltration of glial cells with preservation of neuronal architecture . 
 it is an uncommon glial neoplasm of astrocytic origin that occurs in adults and is exceedingly rare in children.materials and methods : the authors retrospectively analyzed the data of 6 patients of gliomatosis cerebri operated between 2007 and 2012.result:all patients underwent surgical decompression , followed by chemoradiotherapy . 
 the survival ranged between 3 and 45 months . 
 the mean survival was 18.5 years.conclusion:performance scores at presentation and the nonglioblastomatous histology seems to favorably affect the prognosis . 
 larger studies are required to comment on the role of combination of surgery , chemoradiotherapy as a treatment modality .