What effective technique to differentiate radiation brain necrosis from a tumor progression in patients treated with radiation: A monocentric retrospective study combining the MRI TRAMs technique and the (18F)-dopa PET/CT.

PURPOSE: Brain necrosis after radiotherapy is a challenging diagnosis, since it has similar radiological appearance on standard MRI to tumor progression. Consequences on treatment decisions can be important. We compare recent imaging techniques in order to adopt a reliable diagnostic protocol in doubtful situations. PATIENTS AND METHOD: This is a retrospective study comparing the performance of three imaging techniques after radiotherapy of brain metastasis: Perfusion-MRI, TRAMs technique and F-dopa PET-CT. The evolution of the treated metastasis volume was also analyzed by contouring all patients MRIs. All included patients were suspected of relapse and had the three exams once the volume of treated metastasis increased. RESULTS: The majority of our patients were treated by stereotactic radiotherapy. Suspicion of relapse was on average around 17months after treatment. Four cases of radionecrosis were diagnosed and six cases of real tumor progression. Neurological symptoms were less present in radionecrosis cases. All of our radionecrosis cases had relative cerebral blood volume below 1. F-dopa PET-CT succeeded to set the good diagnosis in eight cases, although we found one false positive and one false negative exam. The TRAMs technique failed in one case of false negative exam. CONCLUSIONS: Perfusion-MRI showed high performance in the diagnosis of radionecrosis, especially when calculating relative cerebral blood volume rate. The TRAMs technique showed interesting results and deserves application in daily routine combined with the perfusion-MRI. F-dopa CT might induce false results because of different metabolic uptake according to tumor type, medication and brain blood barrier leak.

Age-related changes in the elastic tissue of the human thoracic aorta.

Thirty human aortas with varying degrees of atheroma graded macroscopically according to the WHO classification were taken at autopsy from subjects of different ages (24-86 years). Study by light microscopy showed aortas with an intact wall (4 subjects, 25-46 years) with a thin intima and regular elastic layers, and aortas with varying degrees of modification of the wall, where the intima was of varying thickness and the elastic fibers showed varying degrees of damage (moderate lesions: 5 subjects, 35-52 yrs; severe lesions: 21 subjects, 26-86 yrs). From each aorta, a 4-cm segment from the tunica media, free of atheromatous lesions, was defatted and subjected to successive treatment with EDTA-Tris, 6 M guanidine-HCl-Tris, 6 M guanidine-HCl-Tris-DTE and collagenase. The residues (EP residues) were subjected to amino acid (AA) analysis and transmission electron microscopy (TEM) study. In the young subject, the AA composition was similar to that of elastin and the TEM images were characteristic of this substance. In the aging subject, an increase in polar AA and a parallel decrease in apolar AA and crosslinks was noted. By TEM, the elastin was seen to be associated with abundant fibrillar material. Trypsin treatment of EP residues gave E residues, whose composition and TEM appearance were similar in all samples, corresponding to the standard composition of elastin and its classic appearance by electron microscopy. We suggest that the fibrillar material removed by trypsin is the morphological reflection of the chemical variations observed in the EP residues. These correspond to contamination of the elastin by a polar protein fraction. This contamination is closely correlated with age but not with the degree of atheroma. Thus the age-related chemical changes in elastin appear to be independent of the onset and evolution of atheromatous lesions. The 10-15 nm diameter of the contaminating fibrillar material suggests that may be the microfibrillar fraction of elastic tissue.

Male breast cancer. A report of 71 cases.

Male breast cancer is rare; it constitutes 0.2-1.5% of all malignant tumours in men and 1% of all breast cancers. The goal of this retrospective study is to analyse the epidemiologic, clinic, therapeutic and evolutive profiles of this disease in 71 cases collected at the National Institute of Oncology in Rabat, Morocco, between the years 1985 and 1998. The median age was 60 years. No significant risk factor was found. The average consultation's delay was 35 months. The main clinical complaint was a mass beneath the areola in 86% of the cases, associated with ulceration in 18% of the cases. For that, the disease was diagnosed at an advanced stage. Infiltrating ductal carcinoma was the most frequent pathologic type (91.5% of cases). Management consisted especially of radical mastectomy, followed by adjuvant radiotherapy and hormonal therapy with or without chemotherapy. It was possible to follow 58 of the patients. The median of follow-up was 30 months. The evolution has been characterized by local recurrence, after a median delay of 36 months, in five cases (8.5% of all patients). Metastasis occurred, after a median delay of 12 months, in 14 cases (24% of all patients). The site of metastasis was the bone in six cases, lung in five cases, liver in one case, liver and skin in one case and pleura and skin in one case. There were three cases of death. In one case, death was related to lung metastases. In the two remaining cases, death was due to comorbid disease. Progression was observed in one case.

Staining of elastic tissue by Verhoeff's iron hematoxylin.

The elastic system of normal human skin was studied by light and immunofluorescence. Oxytalan, elaunin et elastic fibers were stained by weigert, orcein, gomori and Verhoeff. By Verhoeff's method all elastic system of dermis is shown, with other three stains, only elaunic and elastic fibers are well visualized. These results are confirmed by immunofluorescence studies.