50,804 research outputs found
Post-radiation gliomas.
No full textAIMS AND BACKGROUND:
Radiotherapy is important in the treatment of neoplasm of the central nervous system, but various side effects, particularly neoplastic, have been described. Recently, post-radiation gliomas have been reported.
METHODS:
The authors review 88 cases of cerebral glioma following radiotherapy in patients operated for neoplasms of the nervous system, including 6 personal cases of post-radiation gliomas treated in the Neurosurgical Division of the Department of Neurological Sciences, "La Sapienza" University, Rome. The criteria used to define this unusual pathologic association are discussed.
RESULTS:
There was a male predominance. Post-radiation gliomas were particularly malignant, the average dose was 33 Gy, and average free latency was 9.6 years. The first disease was most frequently acute lymphatic leukemia.
CONCLUSIONS:
Post-radiation gliomas have particular features but do not present a histologic or clinical behavior different from analogous spontaneous gliomas. The fact that 88 cases have been reported in recent years suggests that a thorough biological, clinical studies be carried out on this association
Mapping Active and Capable faults in structural complex settings. A case study from central Apennines (Italy)
No full textEarthquake-induced ground effects are strongly related to the presence and distance of active and capable faults, and they play an extremely important role in the mitigation of seismic risk. The Italian Seismic Microzonation Guidelines subdivide the active and capable faults in ‘certain and defined’ and ‘uncertain’, attributing to them microzones with defined landscape uses: ‘Respect’ and ‘Susceptibility’ zones respectively. In this work, we present the methodology used to map and analyze the Montereale basin’s faults, located in the highly seismic region of the central Apennines of Italy. The Montereale faults (MFS) pertain to two fault systems with an en echélon array, namely the San Giovanni and Capitignano fault systems. Yet the great scientific attention in this region, these faults still lack clear evidence of relationships with the major active and capable structures in the neighboring area that are considered responsible for the seismic events that affected central Italy in recent decades.
The San Giovanni fault cuts in heterogeneous deposits consisting of calcareous lithotypes, which expose well defined fault planes and easily recognizable fault scarps. Instead, the Capitignano fault occurs on softer arenaceous-pelitic deposits, which make hard to identify tectonic discontinuities.
The approach, by which we have mapped the Capitignano fault and defined Susceptibility and Respect microzones for the MFS, is divided into the following phases: 1. Identification of morphotectonic elements by the analysis of digital terrain models (DTM 10 m and LiDAR 1 m), morphological elements (linear slopes, non-degraded triangular facets, anomalies in the drainage network, linear valleys, saddles, alignments of slope breaks) represent the most evident expression of active tectonics. 2. Geological and geomorphological survey for the interpretation of the elements recognized by remote sensing data. 3. Geophysical surveys (tomography electrical resistivity and seismic reflection), planned based on the morphotectonic features, identified in the previous stages. 4. Paleoseismological trenches, located where geophysical investigations have confirmed the presence of subsoil’s discontinuities. 5. Dating of faulted soils.
Following this method, the recognition of active and capable faults was possible, even where their morphological expression was not evident or completely absent. Moreover, the study outcomes provided new pieces of evidence for a comparison with the neighboring and well-studied fault systems allowing to propose eventual structural relationships. Finally, we believe that the proposed approach can be a powerful tool in regions densely affected by earthquakes. In fact, a deep knowledge of fault network and their mutual interactions allows to limit damage to people and inhabited centers and to plan reconstruction works in areas affected by seismic events
High-dose radiation-induced meningiomas
No full textBACKGROUND: Numerous neoplasms within the CNS have been reported as radiogenic in origin; radiation-induced meningiomas are at least five times more numerous than gliomas or sarcomas in the world literature. METHODS: The authors review 10 cases of cerebral meningiomas following high-dose radiotherapy in patients operated for neoplasm of the nervous system. The pathologic and clinical aspects of this unusual complication are analyzed in all cases in the world literature. RESULTS: There is a female predominance (F-M ratio: 3:2) and the patients are young (mean age: 33.1 years; median: 29 years). The average latency period is 14.4 years (range: 9-21 years). The first disease is acute lymphocytic leukemia (ALL) in 40% of cases. Radiation induced meningiomas are atypical in four cases. Recurrence was observed in one case without malignant transformation. CONCLUSION: High-dose radiation- induced meningiomas have the following characteristics: (1) children appear particularly sensitive to the development of this tumor; (2) there is a female predominance, otherwise than is observed in lowdose meningioma: (3) these tumors present a peak frequency in the third decade of life; and (4) frequently, these tumors are atypical and recur. Finally, it is essential that every new case be reported to throw light on this particular pathologic correlation with its many grey areas
Metastatic spinal cord compression. Clinical remarks
No full textBACKGROUND: Metastatic compression of the spinal cord is a frequent occurrence throughout the evolution of neoplastic disease. Possible clinical-diagnostic strategies and therapeutic management of this pathology are discussed in terms of survival and quality of life. METHODS: The study includes 59 patients (40 males and 19 females, with an average age of 48.4 years) with metastatic spinal compression treated surgically in our centre (in some cases with stabilization of the spinal segment involved). RESULTS: In 40 cases the localization of the primary tumor was known when the patient was admitted. The segment involved was the dorsal one in 41 cases. The most frequent type of tumor was pulmonary carcinoma in males and breast carcinoma in females. Average survival was 5.3 months. Treatment integrated by stabilization improved the quality of life in comparison to laminectomy alone. Survival was also influenced by the histological type and site of the primary tumor. CONCLUSIONS: Surgical treatment not only prolongs survival but, above-all, guarantees a satisfactory quality of life
High-dose radiation-induced meningiomas.
No full textBACKGROUND:
Numerous neoplasms within the CNS have been reported as radiogenic in origin; radiation-induced meningiomas are at least five times more numerous than gliomas or sarcomas in the world literature.
METHODS:
The authors review 10 cases of cerebral meningiomas following high-dose radiotherapy in patients operated for neoplasm of the nervous system. The pathologic and clinical aspects of this unusual complication are analyzed in all cases in the world literature.
RESULTS:
There is a female predominance (F-M ratio: 3:2) and the patients are young (mean age: 33.1 years; median: 29 years). The average latency period is 14.4 years (range: 9-21 years). The first disease is acute lymphocytic leukemia (ALL) in 40% of cases. Radiation induced meningiomas are atypical in four cases. Recurrence was observed in one case without malignant transformation.
CONCLUSION:
High-dose radiation-induced meningiomas have the following characteristics: (1) children appear particularly sensitive to the development of this tumor; (2) there is a female predominance, otherwise than is observed in low-dose meningioma; (3) these tumors present a peak frequency in the third decade of life; and (4) frequently, these tumors are atypical and recur. Finally, it is essential that every new case be reported to throw light on this particular pathologic correlation with its many grey areas
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