Neural Related Lesions II Flashcards
How common is neurofibromatosis?
Relatively common hereditary disorder that is estimated to occur in 1/3000 births
How many different forms are there of neurofibromatosis? Most common?
8 different forms
Most common = NF type I (NF1)
What is another name of NF1 neurofibromatosis?
Von Recklinghausen’s disease
What causes NF1?
Variety of mutations in the NF1 gene which is responsible for a tumor suppresor protein product known as neurofibromin
What kind of inheritance pattern does NF1 follow?
autosomal dominant
Where do neurofibromatosis lesions (multipl neurofibromas) occur?
Can occur everywhere but most often on the skin
What is the appearance of neurofibromatosis lesions?
Appearance varies from small papules to larger skin nodules to massive, baggy, pendulous masses on the skin
What clinical feature is pathognomonic for NF1?
Plexiform variant of neurofibroma which feels like a bag of worms
What are the major clinical features of neurofibromatosis?
Multiple neurofibromas
Cafe-au-lait pigmentation of the skin (6 or more)
Crowe’s sign (axillary freckling)
Lisch nodules
HTN
Oral Lesions
What is the appearance of lisch nodules?
translucent brown pigmented spots on the iris (2 or more)
What is the characteristic of oral lesions in neurofibromatosis?
Enlargement of fungiform papillae
Radiographic findings:
Enlargement of mandibular foramen
Enlargement or branching of the madnibular canal
Increased bone density
Concavity of the medial surface of the ramus
Increase in dimension of the coronoid notch
What signs are needed to diagnose neurofibromatosis?
2 of the following:
6 or more cafe au lait macules
2 or more neurofibromas of any type of 1 plexiform neurofibroma
2 or more lisch nodules
1st degree relative with NF1
Freckling in axial or inguinal regions
Optic glioma
Distinctive osseous lesion such as sphenoid dysplasia or thinning of the long bone cortex
Tx for neurofibromatosis
Tx directed at prevention and management of complications
facial neurofibromas are removed for esthetics
No specific therapy for NF1
What is one of the most feared complications of neurofibromatosis?
developmeny of cancer, most often a malignant peripheral nerve sheath tumor (neurofibrosarcoma or malignant schwannoma)
What is the average lifespan of patient with NF1?
15 years less than normal
What disease did the elephant man have?
Thought to be neurofibromatosis but had proteus syndrome (ddx)
What is paraganglioma?
Tumors that arise from paraganglia
What are paraganglia?
specialized tissues of neural crest origin that are associated with the autonomic nerves and ganglia throughout the body (some are chemoreceptors like the carotid body)
What are the most common sites of paraganglioma lesions?
Head and neck lesions are hte most ocmmon site
What is the most common paraganglioma tumor?
carotid body tumor which develops at the bottom of the bifurcation of the internal and external carotid bodies
Tx for paraganglioma
May include surgery, radiation therapy or both depending on extent and locatoin of tumor
What is multiple endocrine neoplasia (MEN) type 28?
tumors or hyperplasia of the neuroendocrine tissues
What type of MEN has the most oral manifestations?
type 2B
What are the clinical features of MEN?
Marfanoid body build (thin, elongated limbs and muscle wasting)
Narrow face with thick land protuberant lips because of the difuse proliferation of nerve bundles
Pheochromocytomas of the adrenal glands develop and the tumor cells produce catecholamines resulting in symptoms such as sweating, intractable diarrhea, headaches, flushing, HTN, etc
What is the most significant complication of MEN?
Development of medullar carcinoma of the thyroid gland which occurs in 90% of cases
Marked propensity for metastasis
What cells does medullary carcinoma of thyroid gland in MEN arise from?
parafollicular cells (C cells) which are responsible for making calcitonin
Average age of death for a MEN pt?
21 yo
What are the lab values in MEN pts?
elevated serum or urinary calcitonin (medullary carcinoma of thyroid gland is present)
Increased VMA and epi to norepi ratio (pheochromocytoma present)
Tx for MEN?
Prophylactic removal of the thyroid gland may be recommended
Pt should be observed for pheochromocytomas because it could result in life threatning hypertensive crisis
What is central so a good prognosis for MEN?
Early detection given the serious nature of the medullary thyroid carcinoma
What is melanotic-neuroectodermal tumor of infancy?
Rare pigmented neoplasm that usually occurs during the 1st year of life
What is the cel of origin of melanotic-neuroectodermal tumor of infancy?
neural crest cells
What structure does melanotic-neuroectodermal tumor of infancy usually affect?
Strong predilection for maxilla
What other sites does melanotic-neuroectodermal tumor of infancy affect?
skull epididymis and testis mandible and brain
What sex does melanotic-neuroectodermal tumor of infancy usually affect?
slight predilection for males
Lab values for melanotic-neuroectodermal tumor of infancy
High urinary values of VMA (vanillylmandelic acid)
are melanotic-neuroectodermal tumor of infancy benign or malignant?
Most are benign despite rapid growth and potential to destroy bone
