While low-grade juxtacortical and low-grade intramedullary osteogenic sarcomas are histologically indistinguishable, they
have been studied as separate entities. We retrospectively reviewed the clinical, radiographic, histologic features and treatment
of 59 patients treated surgically to compare the rate of local recurrence, grade progression, and survival between low-grade
intramedullary and low-grade juxtacortical osteogenic sarcoma. Forty-five (76%) patients were treated for low-grade juxtacortical
osteogenic sarcoma and 14 (24%) were treated for low-grade intramedullary osteogenic sarcoma. Local recurrence rates of 7%
were similar for both groups studied. The rate of distant metastases was also similar for both groups. . The rate of dedifferentiation
for the entire group was 29%. Dedifferentiated lesions were treated with adjuvant chemotherapy in 16 of 17 cases. Recurrence
preceded dedifferentiation in four cases. Five-year survival was over 90% in both groups. Low-grade intramedullary and low-grade
juxtacortical osteogenic sarcoma were clinically indistinguishable with identical rates of local recurrence, distant metastases,
dedifferentiation, and survival.
Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Each author certifies that he or she has no commercial associations that might pose a conflict of interest in connection with
the submitted article.
Each author certifies that his or her institution either has waived or does not require approval for the human protocol for
this investigation and that all investigations were conducted in conformity with ethical principles of research.