Resection can alleviate both the seizures and the behavioral and cognitive abnormalities of hypothalamic hamartomas, but complications are frequent.

Cortical dysplastic lesions (CDLs) are usually identified by magnetic resonance imaging (MRI). Clinical, electrographic and histologic findings suggest that focal CDLs (FCDLs) are highly epileptogenic, often involve the rolandic cortex, and can present variable degrees of histopathologic abnormalities. An ictal or "ictal-like" bursting pattern of electrographic activity was recorded over dysplastic cortex in 65% of our patients. Resective surgery can eliminate or significantly reduce seizure frequency in many medically intractable patients, depending on lesion location, degree, and extent of histopathologic abnormalities. Best results are achieved when complete or major excision of both the MRI-visible lesion and the cortical areas displaying ictal electrographic activity can be performed. This is more likely when the degree of histopathologic abnormality is mild to moderate or when the lesion is in a temporal lobe. More severe histopathologic abnormalities and central insular or multilobar lesions usually lead to less favorable results: either major excision of the visualized lesion is impractical or the lesion is microscopically more extensive than shown by MRI. Multilobar resection or hemispherectomy for patients with infantile spasms associated with CDLs and for patients with hemimegalencephaly are often associated with dramatic improvement in seizure control. Callosotomy can be performed in selected patients with diffuse CDLs who have intractable drop attacks.

We report clinical and pathological data of 419 image-guided stereotactic biopsies. In the present series the diagnostic yield, estimated by comparing the original histological diagnoses with follow-up data, was found to be approximately 94% in gliomas. As it has been suggested that malignancy of astrocytic gliomas may be considerably underestimated in the small tissue samples obtained by stereotactic biopsy, we have reviewed 160 adult, diffuse supratentorial astrocytic tumours, correlating the original Kernohan tumour grades with survival. In this grading system, although there was generally a good correlation between histological grade and survival probability (P < 0.0001), no distinction could be made between the grade 3 (anaplastic astrocytoma) and grade 4 (glioblastoma) groups. Tumour grades obtained by applying the criteria of the more recent Daumas-Duport grading system were also determined and correlated with survival. These latter tumour grades not only correlated well with survival (P < 0.0001), but also enabled us to identify a group of patients with intermediate grade malignancy (grade 3, anaplastic astrocytoma), surviving longer than those with grade 4 tumours. Image-guided stereotactic biopsy is a useful means of providing tissue samples for histological diagnosis of brain neoplasms, including gliomas. Histological grading of adult, diffuse supratentorial astrocytic gliomas diagnosed by this technique is possible and should be carried out using an appropriate grading system.

Angiogenesis has been proposed as essential for the growth of solid tumors. The determinants of this process, the growth factors and the vascular endothelial receptors have brought a potential in the tumor prognostic determination as well as perspectives of "targets" for antiangiogenic therapy. In oligodendrogliomas (OL), angiogenesis is little known and/or has generated conflicting results. In order to clarify angiogenesis in OL, we have evaluated the immunohistochemical expression of vascular endothelial growth factor (VEGF) and the microvascular density (MVD) through the expression of TGF-beta (CD105/endoglin) (MVD-CD105) and CD34 (MVD-CD34) receptors using the Chalkley point method in 30 OL. No significant immune reaction was found for the VEGF. There was expression in <10% of tumor cells and/or staining of weak intensity in 15 (50.0%), >10% of cells and moderate intensity staining in 1 (3.33%), and negative expression in 14 (46.67%). If present, the expression was restricted to tumor and endothelial cells. Our findings suggest that VEGF has little influence on OL angiogenesis. All specimens showed CD105 and CD34 expression in the intratumor vascular endothelium, suggesting involvement of CD105 in OL angiogenesis. The mean +/- SD MVD-CD105 and MVD-CD34 were 10.83 +/- 2.24 and 11.00 +/- 2.76 in OL (P = 0.086; r = 0.319); 10.00 +/- 2.00 and 10.40 +/- 3.02 in OL grade II (n = 15) (P = 0.547; r = 0.105), and 11.67 +/- 2.22 and 11.53 +/- 2.45 in OL grade III (n = 15) (P = 0.817; r = 0.551), respectively. The absence of correlation between DMV-CD105, DMV-CD34 and tumor grades suggests that anti-CD105 and anti-CD34 antibodies have different vascular specificities. MVD-CD105 was greater in OL grade III than in OL grade II (P = 0.0032), indicating an increase in the vascular neoformation, something which must be evaluated as a possible prognostic factor in OL. Both TGF-beta and CD105 bring perspectives as "targets" for antiangiogenic treatments in OL.

We report a case of mycetoma caused by Rhodococcus in a 62-year-old man who presented with multiple draining sinuses of the left foot. Biopsy specimen showed granulomatous reaction and microabcesses contained granules. These granules were composed by rod and coccoid Gram-positive and partially acid-fast elements. Culture grew a 'Nocardia-like organism', confirmed at the Center for Disease Control as Rhodococcus spp.