Biomedical subjects

Marc Polivka

Publications and source records attributed to Marc Polivka.

11 recordsLinked to original sources

PubMed2007

MGMT prognostic impact on glioblastoma is dependent on therapeutic modalities.

MGMT promoter methylation, which has been correlated with the response to alkylating agents, was investigated in a retrospective series of 219 glioblastomas (GBMs) treated with various modalities. MGMT methylation had no impact on survival for the whole group, but showed a significant advantage (17.1 months vs. 13.1) for patients treated with RT+ adjuvant chemotherapy (relative risk of death (RR) = 0.53; P = 0.041), particularly when patients received CT during the course of RT (MS = 19.9 months vs. 12.5 months; RR = 0.227, P = 0.001). This suggests that the prognostic impact of MGMT methylation is dependent on therapeutic modalities and schedules. MGMT methylation was not correlated with the main molecular alterations, such as 10q loss and p53 expression.

Adult↗

PubMed2006

Prognostic stratification of patients with anaplastic gliomas according to genetic profile.

BACKGROUND: There is a need to improve the current, controversial, and poorly reproducible classification of anaplastic gliomas, which represent a highly heterogeneous entity in terms of survival. METHODS: The impact of the most common genetic alterations on survival was investigated based on 156 anaplastic gliomas: Among the patients who were included, the gender ratio was 1.32, the median age was 45.5 years (range, 20-83 years), and the median Karnofsky performance status was 70 (range, 40-100). Genetic analysis included a search for loss of heterozygosity (LOH) on chromosomes 1p and 19q; amplification of chromosomes 9p and 10q and of the epidermal growth factor receptor (EGFR), cyclin-dependent kinase 4 (CDK4) and mouse double-minute (MDM2) genes; and p53 expression. RESULTS: The median survival was 33.5 months, and the median progression-free survival was 15.8 months. In a univariate analysis, LOH on 1p and 19q was correlated with longer survival, whereas p53 expression, LOH on 9p, LOH on 10q, amplified EGFR, and deleted CDKN2A were correlated with shorter survival. LOH on 1p and 19q were associated with oligodendrogliomas, LOH on 10q was related to EGFR amplification, and LOH on 1p and 19q was mutually exclusive with EGFR amplification and LOH on 10q. In a multivariate analysis, the significant prognostic factors were age, histology, LOH on 1p and 19q, and P16/CDKN2A deletion. Recursive partitioning analysis (RPA) divided the whole group hierarchically into 3 distinct prognostic subgroups: Group A with 1p19q codeletion (median survival, 98 months), Group B with EGFR amplification (median survival, 17 months), and Group CC (median survival, 31 months), providing a basis for a genetically based prognostic subclassification for patients with Grade III gliomas. CONCLUSIONS: The search for 1p19q codeletion and EGFR receptor amplification provides a simple, clinically relevant prognostic subclassification of grade III gliomas.

Adult↗

PubMed2005

Chromosome 1p loss: a favorable prognostic factor in low-grade gliomas.

Search for loss of heterozygosity on chromosomes 1p, 9p, 10q, and 19q, epidermal growth factor receptor (EGFR) gene amplification, and p53 expression was performed in a series of 131 low-grade gliomas. The profile of molecular changes, clinical findings, and histology were subsequently correlated with the course of the disease, mainly progression-free survival. When these parameters were considered as candidate variables in a multivariate analysis, only loss of heterozygosity on chromosome 1p was associated with increased progression-free survival (hazard ratio, 0.521), indicating a major favorable prognostic role of this genetic alteration in low-grade gliomas.

Adolescent↗

PubMed2005

[Mitochondrial encephalomyopathies].

Mitochondrial encephalomyopathies include various syndromes involving both muscles and the nervous system. They are characterized by morphological and/or functional mitochondrial abnormalities. Relevant histological modifications in muscle are ragged-red fibers with or without cytochrome C oxidase (COX) activity. Neuropathological alterations in the brain are not specific. They consist of spongiosis with or without preferential involvement of territories of "system degeneration", neuronal loss, focal necrosis, capillary proliferation and mineral deposits. Their topographic patterns are characteristic of each syndrome. Mitochondrial encephalomyopathies are due to defects in mitochondrial DNA, sporadic, with maternal inheritance or defects in nuclear DNA with mendelian inheritance. The first group is more frequent including MERRF, MELAS, KEARNS-SAYRE, and some LEIGH syndromes. LEIGH syndrome is also the most frequent in the second group. However, in accordance with the progress in molecular genetics, these syndromes might be reclassified.

Humans↗

PubMed2005

Progression of an osteoid osteoma to an osteoblastoma. Case report.

The authors report the unusual case of a 25-year-old man with occipitocervical pain related to a lesion of the C-1 lateral mass. Initially this lesion measured 8 mm and exhibited radiological features of an osteoid osteoma. Seven years later, as pain increased and became unresponsive to antiinflammatory drugs, computerized tomography scanning demonstrated progression to a 16-mm lesion, highly suspicious of an osteoblastoma. After mobilization of the vertebral artery from the C-1 groove, the lesion was completely resected via an anterolateral approach. Complete symptomatic relief, restoration of cervical range of motion and preservation of cervical stability were achieved immediately after surgery, and the results were confirmed at the 4-year follow-up examination. Pathological examination of tissue samples confirmed the diagnosis of osteoblastoma. Osteoid osteoma rarely evolves to osteoblastoma. Deterioration of a patient's ability to control pain is a warning sign. Insight into such cases underlines the importance of close long-term radiological follow-up examination in patients with conservatively treated osteoid osteomas.

Adult↗

PubMed2005

Cervical dumbbell intra-extradural hemangioblastoma: total removal through the lateral approach: technical case report.

OBJECTIVE AND IMPORTANCE: Extradural hemangioblastomas account for 8 to 12% of all spinal hemangioblastomas. Among them, intra-extradural forms with a dumbbell extension are extremely rare. We report a case of intra-extradural hemangioblastoma involving the C6 cervical nerve root. CLINICAL PRESENTATION: The patient was a 31-year-old woman presenting with signs of myelopathy and C6 radiculopathy on the right side. A computed tomographic scan and magnetic resonance imaging demonstrated a dumbbell tumor that had developed through the C5-C6 intervertebral foramen. Angiography revealed a well-circumscribed mass with feeders from the vertebral artery and the deep cervical artery. INTERVENTION: The tumor was totally removed through the lateral approach, with control of the vertebral artery and sacrifice of the C6 cervical nerve root. Limited bone drilling to enlarge the foramen permitted us to reach and resect the intradural component. Histopathological examination confirmed the diagnosis of hemangioblastoma. Follow-up was uneventful. CONCLUSION: This is the sixth reported case of a cervical dumbbell hemangioblastoma investigated by computed tomographic scanning and MRI but the first one resected via the lateral approach. The lateral approach seems appropriate for surgical resection because it provides primary control of the vascular feeders and access to the extradural and intradural components.

Adult↗

PubMed2005

Case report: human brain abscess due to a tetra-acetabulate plerocercoid metacestode (Cyclophyllidea).

A 38-year-old man living near Phnom Penh (Cambodia) was admitted to a hospital in Paris in June 2001 for a single episode of a generalized grand mal seizure. This episode was preceded by a 9-month history of headaches. Magnetic resonance imaging (MRI) of the head revealed a rounded lesion immediately ahead of the left central sulcus. The resected lesion was about 20 mm in diameter. Histologic examination revealed an elongated but unsegmented metacestode at the center of the lesion. Polymerase chain reaction (PCR) analysis was inconclusive due to formalin-based histologic processing of the tissue. Morphologic analysis based on the histologic sections revealed that the metacestode was a tetra-acetabulate plerocercoid of the order Cyclophyllidea, with a distinct rostellum and pseudosegmentation of the dorsoventrally flattened hindbody. This is the first report of a tetra-acetabulate plerocercoid from a human host and the first report of any cyclophyllidean plerocercoid from the human brain. After 6 weeks, the patient was asymptomatic, neurologic examination was normal, and the brain MRI showed only surgical cavitation. The patient returned to Cambodia.

Adult↗

PubMed2003

[Pituitary germinoma and lymphocytic hypophysitis: a pitfall. Report of two cases].

We report two cases of pituitary germinomas in two young men aged 13 and 21, revealed by insipidus diabetes associated with visual field defects or hypopituitarism. Neuroimaging of the first case was initially normal, then showed an infiltration of the stalk; the lesion of the second case appeared as a nodular thickening of the stalk and subsequently a pituitary infiltration. Histologically they mimicked lymphocytic infundibulo-neuro-hypophysitis (LINH) or lymphocytic hypophysitis (LH), the large tumoral clear cells being out-numbered by the heavy inflammatory stroma or mistaken for macrophages. Only the immuno-staining by placental alkaline phosphatase led to the diagnosis. In these tumours, immunostaining positive for CD-117 and negative for CD30, confirmed the diagnosis and should allow the distinction of pituitary germinoma from other germ cell tumours as recently described in the testis, and may have a therapeutic interest.

Adolescent↗

PubMed2002

Suboccipital and cervical chordomas: the value of aggressive treatment at first presentation of the disease.

OBJECT: Chordoma is a locally invasive tumor with a high tendency for recurrence for which radical resection is generally recommended. To assess the benefits of aggressive treatment of chordomas, the authors compared results in patients treated aggressively at the first presentation of this disease with results in patients who were similarly treated, but after recurrence. METHODS: Among 36 patients with cervical chordomas who were treated at the authors' institution, 22 underwent primary aggressive treatment (Group A) and 14 were treated secondarily after tumor recurrence (Group B). Two cases were excluded from Group A because of unrelated early deaths and three from Group B because of insufficient pre- or postoperative data. Most tumors were located at the suboccipital level and only eight cases at a level below C-2. Radiotherapy and proton therapy were similarly conducted in both groups of patients. The actuarial survival rates were 80 and 65% at 5 and 10 years, respectively, in Group A patients and 50 and 0% at 5 and 10 years, respectively, in Group B patients (p = 0.049, log-rank test). The actuarial recurrence-free rates were 70 and 35% at 5 and 10 years, respectively, in Group A and 0% at 3 years in Group B (p < 0.0001, log-rank test). The numbers of recurrences per year were 0.15 in Group A and 0.62 in Group B (p > 0.05). All other parameters that were analyzed (patient age, delay before diagnosis, clinical symptoms, chondroid type of lesion, and histological features) did not prove to influence prognosis in a statistically significant manner. CONCLUSIONS: Aggressive therapy, combining as radical a resection as possible with radiotherapy, seems to improve the prognoses of suboccipital and cervical chordomas when applied at the patient's first presentation with the disease.

Adolescent↗

PubMed2002

[A palate tumor revealed by pain].

A 41-year-old female presented in April 1996 with a tumor of the hard palate revealed by increasing left palate pain. Adenoid cystic carcinoma was suspected on clinical and imaging data. Two limited surgical procedures showed a tumor histologically made of small lobules of granular cells, PAS positive and expressing S100 protein, infiltrating some medullary spaces of the palatine bone, consistent with a granular-cell tumour. Pain recurred in the territory of the maxillary branch of the left trigeminal nerve (V2). Imaging showed a tumor of the origin of V2-extending through the foramen rotondum. Two radical interventions in September and in October 2000 showed an infiltrating tumor of the V2 and palatine mucosa, with the same histology. There was no immuno-staining for p53, and less than 5% of nuclei expressed Ki67. Malignant Abrikossof tumors are exceptional, morphologically difficult to differentiate from benign ones, only metastasis proving malignancy. Tumor size above 5 cm, recurrence and infiltrative character are considered pejorative. The value of p53 and Ki67 expression remains controversial. We discuss our observation according to these criteria.

Adenocarcinoma↗

PubMedDate not supplied

Digestive smooth muscle mitochondrial myopathy in patients with mitochondrial-neuro-gastro-intestinal encephalomyopathy (MNGIE).

We report 3 new cases of Mitochondrial-Neuro-Gastro-Intestinal Encephalomyopathy (MNGIE) (or Pseudo-Obstruction-Leukoencephalopathy-Intestinal-Pseudoobstruction Syndrome [POLIP]), a rare disease that associates chronic intestinal pseudo-obstruction (CIPO) and neurological symptoms. A review of the 72 reported cases together with these 3 cases revealed that this condition was associated with (a) a specific cluster of neurological symptoms including leukoencephalopathy (96%), polyneuropathy (96%), ophthalmoplegia (91%) and hearing loss (55%); (b) a CIPO syndrome with the presence of small bowel diverticulae (53%); and (c) mitochondrial cytopathy in 36 of the 37 tested patients (2 of our 3 cases), and thymidine phosphorylase gene mutations in all the 37 tested patients (2 of our cases). The etiology of POLIP/MNGIE syndrome appears therefore to be due to a mitochondrial cytopathy secondary to thymidine phosphorylase gene mutation(s). In 3 cases, including 2 of our 3 patients, mitochondrial abnormalities were evidenced at the ultrastructural level in digestive smooth muscle demonstrating that the pathogenesis of gastrointestinal involvement was directly related to mitochondrial alterations in digestive smooth muscle cells.

Adult↗