RESUMO
Background: Astrocytic brain tumors are the most common primary central nervous system tumors, which are classified into four grades. One of the most important pathologic criteria for the diagnosis of higher-grade astrocytomas (especially glioblastoma multiforme) is microvessel proliferation, particularly in the form of glomeruloid complex. Because tumor angiogenesis is a necessary factor for growth and invasiveness of malignancies, microvessel density (MVD) and intensity of angiogenesis may be used to determine the grade of astrocytomas and plan therapy accordingly. We have planned this study to evaluate the relationship between vwf expression in microvessels and different grades of astrocytoma. Materials and Methods: Sixty-four formalin-fixed and paraffin-embedded blocks of surgical specimens with diagnosis of astrocytoma (grades I to IV, each of them 16 blocks) were selected in a simple-nonrandom sampling. Thin sections of tissue blocks underwent immunohistochemical staining for vwf. The stained slides were examined using a light microscope at low (100) and high (400) magnifications. MVD was estimated by calculating the mean number of stained microvessels in three areas of highest vascularization in the high-power field (400). The intensity of staining was determined based on a 3 scale model, in which scores 0, 1, 2, and 3 mean no detectable stain, trace staining, moderate amount of diffuse stain, and strong diffuse staining, respectively. Results: Thirty-six (56%) patients were male and 28 (44%) were female. Scores 0 and 1 of microvessel staining intensity were not observed in any grades studied, but severe staining intensity (score 3) was observed in 18.8%, 37.5%, 56.3%, and 87.5% of grades I, II, III, and IV astrocytomas, respectively. "Vwf vessel index" (MVD staining intensity of microvessels) was 23.84, 25.62, 31.62, and 62.43 in grades I, II, III, and IV astrocytomas, respectively. Conclusion: We found a significant relationship between staining intensity of vwf in microvessels and different grades of astrocytomas. The intensity of microvessel stain increases in parallel with increasing tumor grade. Regarding "microvessel density" and "vwf vessel index," the difference is predominantly between grade IV and all other grades. However, there is no other statistically meaningful difference between grades I, II and III.
RESUMO
Blue rubber bleb nevus syndrome (BRBNS) is a rare disorder characterized by cutaneous and gastrointestinal (GI) venous malformations. The treatment of BRBNS is primarily supportive and ablative. Ablative therapy involves endoscopic or surgical treatment of GI venous malformations. We describe a 20-year-old woman who had multiple venous malformations all over the GI tract as well as cutaneous lesions. She had suffered from several episodes of melena, chronic anemia and fatigue for 10 years, which were treated temporarily by iron supplementation and blood transfusion. The endoscopic examination of the GI tract and total colonoscopy revealed multiple bluish sessile and polypoid venous malformations 2-3 cm in size throughout the GI tract. Argon plasma coagulation (APC) and polypectomy was done for all gastric and colonic lesions, respectively. Ileoscopy showed a large wide base vascular polypoid lesion at about 70 cm from the ileocecal valve with active bleeding; this was removed by snare polypectomy. One week later, she was discharged in good condition. At about 6 months' follow up she did not report any bleeding attack. Endoscopic polypectomy can be useful in patients with large and polypoid lesions of BRBNs which are not controlled with supportive therapy. Further experience is needed to evaluate the risks versus benefits of this approach.