Biomedical subjects

M Poyhonen

Publications and source records attributed to M Poyhonen.

4 recordsLinked to original sources

PubMed1997

Hereditary spinal neurofibromatosis: a rare form of NF1?

We describe a family in which seven members in three generations were affected with a rare spinal neurofibromatosis. The affected adults showed, at the ages of 32, 37, 38, and 61, respectively, multiple spinal neurofibromas symmetrically affecting all spinal roots. Two patients were operated on for histopathologically proven cervical spinal neurofibromas. All patients had café au lait spots, one had several freckles in the axillary area, and two had possible dermal neurofibromas, but iris Lisch-nodules were not present. Other signs of neurofibromatosis types 1 and 2 were absent. A linkage study of the family suggested close linkage to the NF1 locus and excluded it from the NF2 locus. The DNA analysis of histopathologically verified spinal neurofibromas in two patients showed no evidence of LOH at 17q11.2. The findings in the present family, together with those in a family previously described, suggest a clinically distinct form of neurofibromatosis with extensive spinal neurofibromas and café au lait macules, which may be allelic to the NF1 gene.

Adult↗

PubMed1997

Risk of malignancy and death in neurofibromatosis.

OBJECTIVE AND METHODS: Neurofibromatoses are cancer-prone hamartomatoses that involve a variety of tissue and cell types. As part of a population-based clinical and genetic study of neurofibromatosis in northern Finland, all surgical and autopsy specimens of neurofibromatosis patients were retrieved and histologic slides were reviewed. RESULTS: Specimens were available for 69 of the 197 neurofibromatosis type 1 patients identified. Six malignant peripheral nerve sheath tumors and nine other malignant tumors were detected. In this study, the risk for neurofibromatosis-related malignancy was 8%. Nine neurofibromatosis type 1 patients died, at a mean age of 37 years. The cause of death was related to neurofibromatosis in eight. CONCLUSIONS: The risk of developing malignant tumors and early death is increased in patients with neurofibromatosis, the most common malignancy being malignant peripheral nerve sheath tumors. These risks need to be recognized, and the families should be advised to seek genetic counseling and proper follow-up.

Adolescent↗

PubMed1996

Spontaneous decrease of a pilocytic astrocytoma in neurofibromatosis type 1.

A patient with type 1 neurofibromatosis was followed up with neuroimaging over a period of 12 years. A spontaneous decrease in the size of a histologically verified pilocytic astrocytoma was documented on serial CT and MR examinations. Subsequent studies showed the development of a lesion in the contralateral hemisphere with mass effect and contrast enhancement. Results of a biopsy disclosed normal brain tissue; follow-up imaging showed a spontaneous decrease in the size of this abnormality.

Adult↗

PubMed1994

Chromosome 14-encoded Alzheimer's disease: genetic and clinicopathological description.

A family of Finnish descent with very-early-onset Alzheimer's disease has been identified. Genetic analysis of this family eliminated the amyloid precursor protein gene as the pathogenic locus, but strongly implicated a locus on chromosome 14q23.4 between D14S52 and D14S55. The early age at onset of the disease (average, 36 years; range, 35-39 years), the rapid progression, and the early and prominent myoclonus, while they appear to be frequent findings in the chromosome 14-encoded form of Alzheimer's disease, raised the clinical suspicion of prion disease. However, sequencing the prion gene-coding region of 2 affected members of the pedigree failed to show any abnormality. Apart from the presence of modest cortical vacuolar change, the pathological features of our index patient appeared typical of Alzheimer's disease with abundant senile plaques immunoreactive with beta-amyloid, but not with prion protein antibodies.

Adult↗