By Dr. Purav P Patel
Brain metastasis from osteosarcoma is a rare entity. Only 20 cases have been reported in the literature so far. We report an illustrative case of a 12 years old boy presenting with isolated brain metastasis revealing a fibular osteosarcoma.
A 11 years old boy presented with complaints of pain & swelling over medial aspect of Rt. Knee following a trivial fall 5months ago. There is no history of fever, cough, breathing difficulty, weakness of limbs.
He was investigated for the same, at Bangaladesh.
FNAC & open biopsy from proximal Rt. tibia(22/08/03) suggested osteogenic sarcoma.
On admission he had pain over rt. knee with difficulty in walking; there was neurological deficit.
Routine blood parameters & X-ray chest were normal.
On 02/09/03 a open biopsy from Rt. Tibia revealed trabeculae of bone with an infiltrating neoplasm. Numerous calcified osteoid surrounded by oval to fusiform cells with increased mitotic figures, consistent with Osteogenic sarcoma (high grade).
Three cycles of chemotherapy given at 20 days interval (6/9/03, 27/9/03/17/10/03)
Inj. Cisplatin 50 mg. i.v. (Day1,Day2)
Inj. Adriamycin 25 mg. i.v. ( Day1,Day2,Day3)
Rt. Tibia tumor excision & CMP insertion was done on 11/11/03.
HPE revealed tumor cells in sheets & diffuse pattern with cystic changes. Cells were pleomorphic, with hyperchromatic nuclei and osteoid in a lacelike pattern with numerous giant cells & multinucleated osteoblast like giant cells. There was tumor necrosis.
4th & 5th chemotherapy cycle (11/12/03, 24/12/03)
Inj. Methotrexate 9 gm. In NS (Day1)
Inj. Leukovorin 15 mg i.v.6th hourly (Day2, Day3).
CT Rt. Leg (03/01/04) suggested a mass lesion adjacent the anterior cortex of Rt. Tibia (3.5x4cm sized)
Above Rt.knee amputation with biopsy of skin & subcut. Tissue was done on 06/01/04.
HPE suggested malignant tissue with highly cellular oval and pleomorphic cells. Mitosis was increased. Osteoid production & scattered giant cells were present - consistent with recurrent tumor
6th chemotherapy cycle (15/01/04)
Pt. became febrile & on 18/01/04 had Lt. side focal seizure.
CT chest revealed a very tiny nodule in superior & posterior basal segment of Rt. Lower lobe of lung.
Rt. Fronal hyperdense lesion with perilesional edema & mass effect.
On 21/01/04, Rt. Frontal craniotomy & total excisaion of tumor was done.
HPE revealed hemorrhage & foci of necrosis with solid & cystic areas. Tumor cells were oval to fusiform with enlarged hyperchromatic, pleomorphic nuclei and increased mitosis. Osteoid seams & giant cells are seen among tumor cells. Consistent with Metastatic osteosarcoma of the brain.
Primary intracranial OS is a rare tumor that can arise from the osseous skull base, but it also may originate from mesenchymal components such as dura. When an OS occurs in the brain or subarachnoid space, has no dural attachment, and is not metastatic, it can be considered an intradural ESOS or intradural primary OS (IPOS).
Primary mode of metastasis for osteosarcoma is hematogenous. Most common prognostic factor in osteosarcoma is metastasis at presentation. Metastases usually manifest within 18-24 months of primary disease. 80% of all patients with diagnosis of osteosarcoma already have pulmonary metastatic lesion even if they are not obvious on X-rays.
The heart & abdominal viscera are less commonly involved & generally seen either preterminally or at postmortem; rarer still, is the brain involvement.
According to the current literature, 10-15% of all osteosarcoma patients experiencing relapse may bear risk for CNS metastases. Osteosarcoma may develop years after radio surgery for a benign brain neoplasm.
a recent review
of the literature…:
*Ashkan et al described 19 de novo cases of POS, including 14 arising from bone, four originating from dura, and one that could not be classified further because it involved both skull and dura.
*Keyoumars Ashkan ,Jonathan Pollock: Four cases of intracranial osteosarcoma are reported. In three cases the tumors were primary neoplasms arising from the sellar region, base of the occiput and the parieto-occipital area. One case represented osteosarcoma metastatic to the cerebellum.
*Primary intracerebral osteosarcoma: A case report. Glenn S. Bauman ,William M. Wara A 3 year old girl with a primary, intraparenchymal cerebral osteosarcoma, the second case reported in the literature, is described .
*Sarcoma Metastatic to the Brain: A Series of 15 Cases Maurizio Salvati M.D., Luigi Cervoni M.D., Riccardo Caruso M.D. Franco Maria Gagliardi M.D. and Roberto Delfini M.D.