neurofibromatosis type 1 ( nf-1 ) is an autosomal dominant disorder affecting 1 in 25003500 individuals .
the fact that it is a progressive disorder and that almost 50% of cases are sporadic mutations multiplies its clinical magnitude several folds .
discuss a report in which they described and classified seven different types of nf . of these , nf-1 and nf-2
it is a distinct relative of nf-1 but is 10%20% rarer , accounting for approximately one case in 36,00080,000 individuals .
we present a case ; there was nf-1 with an extra calvarial plexiform neurofibroma ( pnf ) in occipito - cervical region with intracranial extension . a large portion of the visible swelling consisted of a neurofibroma and multiple caf au lait spots on the left upper and lower trunk [ figure 1 ] .
swelling was excised completely . ( a ) clinical photographs showing the occipito - cervical swelling .
( b ) clinical photographs showing caf au lait spots on the left side of upper and lower trunk
this 5-year - old boy presented with history of a gradually progressive painless swelling in the occipito - cervical region since birth . on examination
, he had a large ( 10 cm  10 cm  5 cm ) occipito - cervical swelling , that was soft and nonfluctuant , and transillumination was negative .
the boy had no neurological deficits and no signs or family history of nf-1 . in neuroimaging studies ,
the lesion was seen as an isointense on t1-weighted and heterogeneously hyperintense mass on the t2-weighted image and heterogeneous enhancement mass on postcontrast study [ figure 2 ] .
there were multiple small underlying bone defect in the right occipital region [ figure 3 ] .
the excision was total , and cerebrospinal fluid ( csf ) leak was seen on bone defect site , so periosteum was buried on bone defect site for preventing the csf leak .
histopathological findings in hematoxylin and eosin staining were showing focal myxoid generation and spindle cells , with serpentine nuclei and wispy cytoplasmic border suggestive of pnf .
t1-weighted with postcontrast sagittal magnetic resonance image shows heterogeneous enhancement lesion in the scalp of the right occipital region and nape of neck ( a and b ) both photographs showing three - dimensional computerized tomography skull showing thing of occipital bone right - sided with multiple bone defects
after that pnf of scalp reported by ohaegbulam . in general , pnfs are found in association with nf ( in 26.7% of patients ) .
pnf is usually found along the course of a major nerve trunk , the ophthalmic division in the face .
it is an unencapsulated lesion and infiltrates the surrounding soft tissue to produce a fusiform appearance .
it usually involves one large segment of the body and may involve both sides of the body either symmetrically or asymmetrically .
the patient in this report had a pnf with nf and with telangiectatic discoloration of the overlying swelling , with multiple caf au lait spots on the left upper and lower trunk .
only nine reports were found in the literature , of these nine , one case had nonoperative management , and two had only a biopsy . in the initial description by helmholtz and cushing , as detailed by scott , the location of the pnf was at the forehead and temporal region . it was suggested then that there was a propensity for the forehead and the temporal region , especially the area of the scalp innervated by the trigeminal nerve .
although the forehead and the distribution along the course of the trigeminal nerve are the most common location , there have been a few reports of the pnf occurring at the occiput detail given in table 1 ; pnf occurs with slight male preponderance ( male / female 7:5 ) .
most reported cases have been congenital , but presented later in life due to apprehensions of a social or psychosocial nature , mostly previous reported cases , there was only thinning of the occipital bone with no true dysplasia .
review of literature of occipital neurofibroma nf is generally considered to be a neurocutaneous disorder of neural crest origin with very little emphasis on osseous abnormalities , although osseous dysplasia is one of the seven criteria for diagnosing nf-1 .
most of the osseous lesions are thought to be secondary to the altered functioning of the nf-1 gene .
besides true dysplasias , the secondary involvement of the bones may be due to compression of the malignant tumors seen in association with this disorder , such as malignant peripheral nerve sheath tumors and rhabdomyosarcomas .
osseous manifestations in nf-1 are relatively common and occur in up to 50% of patients with nf-1 .
there are only a few cases reported , and in most , it is difficult to ascertain whether the osteolysis was a result of the erosion secondary to the giant tumor or was merely associated as part of the disease syndrome .
surgery for pnf has been described as being difficult because these tumors are usually very vascular , and torrential hemorrhage has been reported .
there have been earlier reports of tumor firmly adhering to a dominant transverse sinus precluding complete excision . even in patients
in whom there was no involvement of the sinuses , some authors have avoided reconstruction due to the theoretical risks of csf fistulas , the risk of malignancies in nf-1 is approximately 2.7% more than in the general population .
there is approximately a 10% chance of malignant transformation reported in an existing case of nf .
early surgical management should be the treatment of choice , not only just for cosmetic considerations but also for the theoretical risk of malignant transformation .
however , the occurrence of osteolysis may also be prevented if it is indeed secondary to the pressure effects of the lesion , which can not be disproven conclusively .
 plexiform neurofibroma ( pnf ) of the scalp is an extremely rare lesion reported in association with neurofibromatosis ( nf ) . 
 occipital location of pnf is even more infrequent ; we reported one pediatric case of pnf in occipito - cervical region with multiple small occipital bone defects and associated with nf-1 . 