Biomedical subjects
Publications and source records attributed to A G Korshunov.
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Chondrosarcomas located in the anterior cranial fossa are rare. They usually invade the ethmoid sinus and may involve the orbit. We observed two such cases in the last five years, during which approximately 10.000 patients with histologically verified brain tumors were admitted to our Institution. CT and MRI represented the chief diagnostic tests. A combined staged procedure using an initial subfrontal approach, followed by a lateral rhynotomy at a later stage, was performed in the patients described herein. Total tumor removal was possible in both cases. Radiotherapy was not administered to the second patient, in whom surgery allowed gross total removal of the mass. Experience with the present cases of anterior fossa chondrosarcoma, though limited, is encouraging. The pertinent literature is reviewed, and guide-lines for the management of these rare tumors are outlined.
The natural progression of the infiltrative anterior skull base meningioma, expanding into orbit, paranasal sinuses, nasopharynx, and oropharynx during 12 years is presented. The development of the lesion is demonstrated on computed tomography. The patient was operated on six times from the age of 14. Pathological investigation revealed infiltrative meningoteliomatous meningioma without signs of malignancy.
A highly ossified teratoma was diagnosed and surgically treated in a 2-year old girl. More than 150 teeth were macroscopically identified during the operation. Pathological study established the diagnosis of mature teratoma with teeth formation. Only six analogous cases have been reported previously and only two patients survived the operation.
242 cases of brain arterio-venous malformations (AVM) are analysed clinically and anatomically. Their pathology, histological, ultrastructural and immunohistochemical characteristics, therapeutic pathomorphosis are described. The concept is suggested according to which AVM is a collective term including true developmental defects, dysembryogenetic tumors and outcomes of various pathologic processes (trauma, brain circulation and compensatory-adaptive disturbances, etc.). The necessity of therapeutic methods corrections in agreement with the disease pathogenesis is outlined.
Clinical and morphological studies were undertaken to examine 168 patients with glioblastomas of the cerebral hemispheres. They revealed that the longevity of the hemispheres was substantially influenced by three immunobiological criteria: the proliferative potential defined as a labelling index (LI) of proliferative cell nuclear antigen (PCNA), the expression of intracellular domain of epidermal growth factor receptor (EGFR) and the rate of apoptosis identified by ISEL. The risk for shorter survivals increases with higher PCNA LI and with the EGFR expression in the tumor. In contrast, the rate of apoptosis is a good predictor since the risk for shorter postoperative survivals progressively reduces with high apoptotic indices. The expression of cancer proteins p53 and bc12 in the glioblastomas produces no noticeable effect on the patients survival.
The paper describes a rare combination of atypical meningioma of the base of the skull, which was greatly extended, with a life-time unrecognized small vascular malformation of the brain stem at the level of the pons. Intraoperative hemorrhage into the stem from the micromalformation was a cause of the female patient's death. A detailed account of the operation and the postoperative period and a review of literature on the main aspects of the problem in the diagnosis of cerebral micromalformations are given.
The paper describes the most infrequent case of cryptococcal granuloma of the midbrain in a HIV-negative female patient aged 41 years. The patient with midbrain lesion without signs of meningitis was found to have a bulky midbrain opercular formation that was regarded as a nodal glioma. The diagnosis of cryptococcal granuloma was established after removal of the formation (via occipito-transtentorial access with dissection of the lamina tecti) and pathomorphological examination. Microbiological studies verified the diagnosis. Despite the initiation of specific treatment with amphotericin B, the patient died on day 12 following surgery for cryptococcal meningoencephalitis.
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Fifteen patients with focal lesions of temporal epilepsy were examined before and 6 months to 4 years after surgery. There were low-grade gliomas in 13 cases, muscle tissue heterotopy in 1 case, and medial temporal sclerosis in 1. Epileptogenic lesions were localized in the medial structures of the temporal lobe in 10 cases and in the lateral temporal regions in 5 cases. Comprehensive neurophysiological study, including intraoperative electrocorticography, was used to identify an epileptogenic zone (EZ). EZs were found in the medial structures on the affected side in all patients. Lesionectomies were performed in all cases. It was combined with medial resection in 12 cases (it was done in 10 patients until epileptic activity disappeared). Nine patients stopped having seizures after surgery. One patient had only auras. Improvements were slight in 5 patients. A relationship was found between the surgical outcomes and the site of a lesion and EZ. They authors conclude that complete recovery may occur in cases with medial locations of a lesion and EZ. The outcomes of surgery are much poorer in cases with the lateral sites of an lesion and in those with the medial site of EZ.
Chondrosarcomas are malignant mesenchymal tumors of chondroid nature. Less than 5% of all chondrosarcomas are localized in the head and neck. The paper analyzes a case of extensive chondrosarcoma of the skill base, which involves the anterior and median cranial fossa, ethmoidal, sphenoidal, right maxillary sinuses, and intratemporal fossa. A basal approach that is a combination of two-flapped subfrontal and orbitozygomatous accesses was used to remove the tumor. In doing so, the tumor could be excised and extensive defects of the skull base could be effectively closed with the flaps of the periostium and musculus temporalis, yielding a good functional and cosmetic effect.
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Routine pathological examination cannot precisely predict the clinical course of meningiomas because even histologically benign tumors may recur after total removal. And so, numerous efforts have been made for evaluation of meningioma growth fraction and its prognostic value. In this study the prognostic significance of DNA toposiomerase II alpha (topoII) and cyclin A immunohistochemistry was examined in a series of 263 meningiomas. The topoII and cyclin A scores exhibited a close correlation with Ki-67 immunostaining. Significant differences between the indices for all the three markers were noted among the three grades of meningiomas. The scores for all the three markers were significantly different between recurrent and non-recurrent meningiomas including removed benign tumors. The most important information for an individual clinical outcome of histologically benign meningiomas should be elicited from simultaneous evaluation of all the three proliferative markers.
Comparing of the craniopharyngiomas cyst fluid, collected during the surgery, with blood plasma revealed significantly enhanced lipid peroxidation and lactate accumulation in tumour cysts contents. These processes were usually more prominent in endosuprasellar than in suprasellar craniopharyngiomas. The maximum of free radical formation in conjunction with the lowest level of malondialdehyde (MDA) was observed in primary tumours with relatively high proliferation rate. Controversial parameters ratio characterised the recurrent craniopharyngiomas, and in cyst fluids of the primary tumours with low proliferation rate the medium parameter's values were observed. Thus, the estimation of free radical formation level and MDA concentration in cyst fluid of craniopharyngioma seems to be prognostic for the tumour recurrence.
We studied the temporal and spatial profile of apoptosis following acute spinal cord (SC) injury in rats and influence of chicken yolk transplantation on the programmed cell death. 18 female rats were subjected to complete SC transsection with removal of three millimeters of the SC at the level of the ninth thoracic vertebra. The gap was filled with denaturated chicken yolk in 9 animals. 9 control rats had no transplantation. Temporal and spatial course of apoptosis was estimated in longitudinal sections of the SC by TUNEL assay technique 4 hours, 3 days, 2 weeks, 40 days and 3 months after the injury. Apoptosis occurred through all posttraumatic period with its peak 40 days after the injury and decreased slowly to the minimal level by the third month. Apoptotic cells appeared near the site of the injury immediately after the trauma along the cord several hours later. Apoptosis involved only glial cells, neurons had no apoptotic signs. Suppression of apoptosis occurred in the yolk transplantation group and was accompanied by greater number of neuronal and glial survivals. Thus, apoptotic glial death after transsection of the SC in rats occurred mainly for the first eight weeks along the whole spinal cord.
The paper presents a rare case of malignant transformation of an epidermoid cyst to the keratinizing type of squamous cell carcinoma. In a 47-year-old female patient with severe visual disturbances, MRI scans revealed a large supracellular tumor spreading to the third ventricle and medial portions of temporal lobes. The tumor was removed. A histological study of its biopsy specimen showed signs of both a benign process (epidermoid cysts) and its malignant epidermoid degeneration to the keratinizing type of squamous cell carcinoma. After 12-month combined therapy there was a continuous tumor growth with a significant dissemination within the base of the skull. The pathogenesis of epidermoid cysts, possible causes of malignant transformation, modalities of treatment and prognosis are briefly discussed.
The paper analyzes the capacities of computed tomography (CT) and magnetic resonance imaging (MRI) in the postoperative period to evaluate the efficiency of surgical removal of the most malignant type of gliomas of the cerebral hemispheres. A total of 45 patients with different histological forms of cerebral hemispheral gliomas were examined, 37 of them with glioblastomas. Comparison of the results obtained by CT and MRI within the first 24 hours indicated that the latter was of greater informative value in all cases. At the same time only the use of a strict methodological approach to postoperatively estimating the remaining portions of glioblastomas makes it possible to apply these two methods as objective criteria for evaluating the efficiency of removal of a glioblastoma and hence the efficiency of subsequent therapeutic protocols. Contrast-enhanced MRI may be regarded as the method of choice in the primary assessment of patients with suspected recurrent glioblastoma.
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