PMC3994685_01
Skull film, lateral projection showed a rounded osteolytic lesion with a nonsclerotic rim in the left parietal bone
SNI-5-27-g001.jpg
PMC3994685_01_SNI-5-27-g001.jpg
F1
An oval radiolucent line was observed in the left cranium upon simple head X-ray [Figure 1].
(a) A preoperative enhanced computed tomography revealed a bone defective part and an enhanced mass. (b) A preoperative Gadolinium enhanced T1-weighted image demonstrates the presence of a mass, which is enhanced with dural surface and subgaleal tissue. (c) Fluorodeoxyglucose positron emission tomography shows a high uptake in the osteolytic lesion obsereved on the left. (d) Methionine positron emission tomography demonstrates a high uptake in the marginal zone of the osteolytic lesion and dura matar, and a low uptake in the central zone of the osteolytic lesion
SNI-5-27-g002.jpg
PMC3994685_01_SNI-5-27-g002.jpg
F2
A slightly heterogeneously enhanced tumor in left parietal bone was observed inside the bone defect in a gadolinium-enhanced T1-weighted image upon head magnetic resonance imaging (MRI); wherein, the dura mater and subcutaneous tissue contacting the tumor widely exhibited an enhancing effect and was found to have thickened [Figure 2a and b]. Nuclide accumulation was observed in the tumor inside the bone defect upon FDG-PET; however, the brain cortex accumulation was also high in the area adjacent to the brain surface, so the border was unclear, making evaluation difficult [Figure 2c]. Meanwhile, such accumulation was observed to be poor in the center of the tumor upon Met-PET, while accumulation with a well-defined border was observed in the border as well as the dura mater and subcutaneous tissue adjacent thereto [Figure 2d].
(a) Preoperative methionine PET. The red line shows the range of the bone excision. (b) Postoperative CT scan (bone image) (c) Intraoperative photograph of the bone. We performed bone excision and established a border, which was located about 1 cm from the tumor location. (d) Preoperative methionine PET. The yellow line shows the range of the dura excision. (e) Magnification image of the methionine PET (f) Preoperative enhanced T1-weighted image. The yellow line shows the range of the dura excision. (g) Postoperative enhanced T1-weighted image. (h) Intraoperative photograph of the brain surface. No invasion to the brain was observed. (i) Photograph of the dura mater. No tumor cells were observed in all excised specimens
SNI-5-27-g003.jpg
PMC3994685_01_SNI-5-27-g003.jpg
F3
A craniotomy was carried out leaving a distance of approximately 3 cm from the defective part of the bone such that the range observed with accumulation upon Met-PET was sufficiently included [Figure 3a-e]. The dura mater was excised, while leaving a border of approximately 1 cm from the thickened part of the dura mater [Figure 3f-i]. The defective part of the bone was excised upon providing a border of approximately 1 cm [Figure 3c], and this was supplemented using artificial bone Biopex .
(a) Preoperative methionine PET. Arrow (D). Arrow head (e) (b) Postoperative CT scan (bone image). Arrow (D). Arrow head (E) (c) Photograph of the surgical specimen. Arrow (D). Arrow head (E) (d) Photomicrograph of the section D demonstrates fibrotic cell and less giant cell (hematoxylin and eosin stain, x400) (e) Photomicrograph of the section E demonstrates multicleated giant cell (hematoxylin and eosin stain, x400)
SNI-5-27-g004.jpg
PMC3994685_01_SNI-5-27-g004.jpg
F4
The accumulation of tumor cells having a nuclear groove and constricted nucleus in the border part observed with accumulation upon Met-PET was observed inside the extracted skull [Figure 4a-e]. The center part with poor accumulation lacked tumor cells, with fibrous tissue accounting for most parts [Figure 4d].   Accordingly, it was diagnosed as LCH.
(a) Postoperative enhanced T1-weighted image. Red arrowhead (d). Yellow arrow (E). Blue arrowhead (F). (b) Preoperative methionine PET. Red arrowhead (D). Yellow arrow (E). Blue arrowhead (F). (c) A photograph of the surgical specimen. Red arrowhead (D). Yellow arrow (E). Blue arrowhead (F). (d) A photomicrograph of section D shows no tumor cells (hematoxylin and eosin stain, x40) Blue arrow (G). (e) A photomicrograph of section E demonstrates tumor infiltration into the dura mater (H and E, x40). (f) A photomicrograph of section F reveals no tumor cells (H and E, x40). (g) Photomicrograph of section G demonstrates tumor infiltration into the dura mater (H and E, x400)
SNI-5-27-g005.jpg
PMC3994685_01_SNI-5-27-g005.jpg
F5
The dura mater was observed to have undergone invasion of histiocyte-like tumor cells and eosinophil similar to the tumor itself in the region corresponding to the accumulation region upon Met-PET [Figure 5a-g].