Cytogenetic analysis of rare orbital tumors: further evidence for diagnostic implication.

INTRODUCTION. The pathologic diagnosis, and hence the management, of rare tumors of the orbit can represent a challenge. An increasing number of tumors have been shown to display specific chromosomal abnormalities detectable by cytogenetic analysis. MATERIALS AND METHODS. Two examples of rare primary orbital tumors are presented in which the correct pathologic diagnosis was either established or confirmed by cytogenetic analysis. Small pieces of the tumor were obtained at the time of biopsy and placed immediately, in a sterile fashion, in fresh culture medium. The cells were Giemsa stained and processed for chromosome analysis. RESULTS. In the first case, a 12-year-old boy was diagnosed with a sino-orbital mass after sustaining minor trauma. On biopsy, the pathologic examination was at first consistent with a Burkitt-like lymphoma, until cytogenetic analysis showed a t(8;21)(q22;q22) translocation, specific for granulocytic sarcoma, which corresponds to the localized solid form of acute myeloblastic leukemia. Consequently, proper chemotherapy was re-oriented and remission was achieved. In the second case, a 2-year-old boy presented with a well-vascularized orbital tumor. The histopathologic diagnosis of alveolar soft-part sarcoma of the orbit was confirmed by the finding of a specific t(X;17)(p11;q25) translocation. After two unsuccessful courses of chemotherapy, wide excision surgery with primary reconstruction brought remission. CONCLUSIONS. Cytogenetic analysis should be considered in the diagnosis of any orbital tumor which is suspected of malignancy.