Adamantinoma The adamantinoma of bone is an extremely rare primary sarcomaof bone, accounting for about .3% of all malignant tumors of bone,and in 90% of the cases it will be seen in the diaphyseal portion ofthe tibia, especially in the anterior cortex. It occurs equally in malesand females, typically in the second and third decade of life. Thetissue of origin still remains a mystery but immunohistochemicalstains suggest an epithelial origin that might account for why theyare more common just beneath the skin in the anterior cortex of thetibia. Radiographically, the adamantinoma takes on the appearanceof a fibrous dysplastic lesion or perhaps osteofibrous dysplasia ofthe tibia. The lesion appears benign with a lytic core surrounded bydense, reactive fibro-osseous bone that frequently dilates the anteriorcortex and may be multiloculated in appearance. The tumor is quiteslow growing and is usually painful, whereas in fibrous dysplasiaand osteofibrous dysplasia, the patients remain asymptomatic. If a
so-called fibrous dysplastic lesion continues to grow past maturity,a physician should suspect adamantinoma, especially if the lesion ispainful, and look for the characteristic nests and cords of epithelial-looking cells surrounded by fairly benign-appearing fibro-osseoustissue on histological specimens. It is very rare for this tumor tometastasize to different sites but occasionally it will metastasize toregional lymph nodes and the lung. Treatment for this low grade lesion is purely surgical, consistingof a wide local resection, frequently a segmental resection of themid portion of the tibia, and reconstruction with a large boneallograft over an intramedullary nail. There have been a few rarecases in the literature where adamantinoma has arisen out of a pre-existing osteofibrous dysplastic lesion.
CLASSICCase #21425 year male withadamantinoma tibia
Chordoma The chordoma is a very rare malignant tumor of bone thataccounts for only 4% of all malignant bone tumors. It arises fromthe primitive notochord of the axial skeleton and is most commonlyseen in the lower portion of the sacrum, accounting for 50% of thechordomas. 37% arise in the spheno-occipital area and a smallnumber occur in the cervical and lumbar spine. The more commonsacral lesions are seen in an older age group between the ages of40 and 80 years, compared to the spheno-occipital chordomas thatoccur in a younger adult age group. The later carry a much worseprognosis because of the location at the base of the skull. Thechordoma is clinically similar to a mucinous type of chondrosarcoma. In the sacral area, chordomas are usually attached to the anteriorportion of the distal three segments of the sacrum and grow in theretroperitoneal space, pressing up against the rectum whereeventually they will present with clinical symptoms related toconstipation and can be picked up on a rectal examination. Because
the tumor is very slow growing, it rarely causes significant painsymptoms. The radiographic findings are frequently not very obvious,even with large tumors that are better evaluated by soft tissuetechnique, such as CT scan or, better yet, MRI. Microscopically, thechordoma has a mucinous appearance similar to a low grade myxoidchondrosarcoma, but the diagnostic feature is the “signet ring”appearance of the physaliferous cells that have a peripheral nucleus,a large cytoplasmic inclusion of physaliferous mucinous material thatcan look a bit like a liposarcoma. Treatment for the chordoma consists primarily of a wide surgicalresection, which sometimes is very difficult, especially with lesionsextending into the upper sacral segments where the nerve rootsbecome a problem and may result in significant neurogenic boweland bladder complications. Even with surgical treatment, the localrecurrence rate is very high so that post op radiation therapy isrecommended. It has cut the local recurrence rate to about 30%compared to 65% without RT. Recurrences can occur locally up to
fifteen years after the original surgery. Pulmonary metastases areextremely rare and systemic chemotherapy is not indicated for thistumor.
CLASSIC Case #219 45 year male with chordoma sacrum
Eosinophilic Granuloma (Langerhans Histiocytosis) The so-called benign histiocytoses, sometimes referred to as histiocytosis X, include various disease conditions such as eosino- phillic granuloma, Hand-Schuller-Christian disease and Letterer- Siwe disease. Eosinophillic granuloma is the most benign of the histiocytic disorders, followed next by Hand-Schuller-Christian disease that presents with an intermediate diffuse process of both bone and soft tissue that can be fatal. Letterer-Siwe disease is the most aggressive and fatal form of the histiocytoses, presenting like leukemia with a very poor prognosis for survival. Eosinophillic granuloma, now referred to as Langerhans histio- cytosis, is a benign histiocytic disorder that frequently presents in children between the ages of 5 and 15 years with a clinical picture that can masquerade as a malignant neoplasm such as Ewing’s sarcoma. It occurs twice as often in males than females. It is usually a monostotic disorder of the skeletal system, however, in
10% of cases it will be seen in two or three separate sites. Theetiology of this histiocytic process is still unknown but some havepostulated a viral etiology. Patients present with inflammatory pain,more severe at night, that may be associated with a low grade feveror elevated sed rate. The most common location is in the skull,followed next by the ribs, pelvis, maxilla, vertebral body, clavicleand scapula, in that order. Besides flat bone involvement, it iscommonly seen in the diaphyses of long bones where it canmasquerade as Ewing’s sarcoma, but can also occur in metaphysealbone and is found least commonly in epiphyseal bone. In youngchildren, the condition can be extremely permeative and destructivein nature, taking on the appearance of Ewing’s sarcoma, metastaticneuroblastoma, or acute osteomyelitis. On x-ray, eosinophillic granuloma has an onion-skin appearancesimilar to a Ewing’s sarcoma. In an older age group, the conditiontends to be more focal and more granulomatous in appearance withless permeative change. Microscopically, there are large, pale-
staining histiocytes speckled with small, bright-staining eosinophilsand an occasional giant cell. Eosinophillic granuloma tends toinvolute spontaneously without treatment and therefore symptomatictreatment should be conservative--simple curettement for diagnosticpurposes and perhaps cortical steroid injections can be beneficial toinhibit the inflammatory process. In more difficult parts of the body,such as the spine or pelvis, very low grade radiation therapy can beconsidered, realizing that this could convert the process to a malignantsarcoma at a later date. In more aggressive forms with multi-focalinvolvement, especially if there is soft tissue involvement of the skin,lymph nodes or lung, a low dosage chemotherapy program can beconsidered. Sometimes the low grade eosinophillic granulomahistiocytosis can upgrade to a more aggressive and dangerous formsuch as Hand-Schiller-Christian disease or even Letterer-Siwe disease.With spinal lesions, spinal cord compression can result in paraparesisrequiring laminectomy decompression. However, kyphotic deform-ities in younger patients tend to correct spontaneously without surgery.
Sagittal T-2 MRI showing protrusion into vertebral canal
Case #439 new collapse19 year male with EG collapse new collapseat 3 different levels but at olddifferent times oldThe lower levels show heightrestoration as a spontaneoushealing process seen in children old old
Case # 4407 year female withhealing collapsedlumbar vertebra
Case # 44115 year male withEG lumbar vertebra
Hand-Schiller-Christian Disease Hand-Schiller-Christian disease is the intermediate form ofhistiocytosis-X that involves predominantly children, two-thirds ofthe cases being younger than five years of age. The classic triadfor this syndrome is diabetes insipitus, exophthalmos, and singlegeographic lesions involving mostly the skull and pelvic bones.The initial lesions appear like eosinophillic granuloma and, in fact,eosinophillic granuloma can progress into a Hand-Schiller-Christiantype syndrome as the disease advances. It is common to have softtissue involvement of lymph nodes, liver, spleen, lung, brain andkidney as well as skin changes that can be seen in eosinophillicgranuloma. Histologically, the same histiocytic cells as are seenwith eosinophillic granuloma are present, along with eosinophils. Inthe later stages, foam cells and cholesterol deposits are typical.as the disease progresses and more and more soft tissue organs areaffected, the prognosis worsens with an overall fatally rate of
10-30%. Treatment consists of local surgical treatment plus systemictreatment consisting of therapeutic protocols similar to those used inleukemic patients.
CLASSIC Case # 445 5 year male with HSC disease skull
reactive bonegranulomaPhotomic from edge of skull lesion
Letterer-Siwe Disease Letterer-Siwe disease is the least common of the histiocyosescomprising about 10% of all histiocytic disorders. It is a pro-gressive, acute syndrome in children under three years of age,involving multiple visceral organ systems, such as the spleen,lymph nodes and skin, associated with purpura, bleeding gums,and multiple lesions similar to those seen in Hand-Schiller-Christian disease. The skull and pelvis are frequently involved.The skeletel lesions tend to be more diffuse than with the otherhistiocytoses and take on a picture similar to that of leukemia ordiffuse lymphoma. These patients usually die of bacterial infectionswithin one or two years of their acute clinical onset because of bonemarrow suppression. Histologically, the lesions look very similarto eosinophillic granuloma or Hand-Schuller-Christian disease,although it is unusual to see foam cells in this form of histiocytosis.Treatment consists of chemotherapeutic agents similar to thoseused in leukemia.
CLASSIC Case #447 3 year female with LS disease skull
Sinus Histiocytosis Rosai-Dorfman’s Disease Sinus histiocytosis is a rare and new variant of the histiocytoseswhich is characterized by enlarged lymph nodes in the head andneck area in 80% of cases along with bony involvement in 40%of cases. It is an aggressive form of the histiocytoses that is seen inteen agers and young adults. Symptoms may include fever, weightloss and malaise. The bony lesions may be solitary or multifocaland suggest inflammatory disease such as chronic osteomyelitis orEG. The pathology shows mononuclear or multinuclear giant cellswith lymphs in the cytoplasm of the giant cells. Other inflammatorycells such as plasma cells, lymphocytes and foamy histiocytes maybe seen. 10% of those with bone lesions die of the disease from extra-skeletal involvement of the lungs and kidneys.
Case #450.1 Rosai-Dorfman’s disease 52 year old female with knee pain for 1 year