Characteristics of Myelogram in Patients with Extraocular Metastatic Retinoblastoma and Morphological Analysis of Tumor Cells in Bone Marrow and Cerebrospinal Fluid

Abstract

BACKGROUND: Retinoblastoma (RB) is a common intraocular malignant tumor in infants and young children. However, reports on the morphological descriptions of RB tumor cells from native and foreign scholars are rare. OBJECTIVES: To investigate the myelogram characteristics of RB with extraocular tumor extension and the morphological characteristics of tumor cells in the bone marrow and cerebrospinal fluid. METHODS: For the period from May 2011 to February 2015, we analyzed clinical data on 18 patients in our hospital diagnosed as having metastatic RB in the extraocular and other distant regions associated with clear bone marrow metastasis. The morphology of tumor cells in the bone marrow and cerebrospinal fluid was retrospectively analyzed after staining with Wright-Giemsa stain. A summary of the cytological characteristics was also presented. RESULTS: RB tumor cells in the bone marrow and cerebrospinal fluid not only appeared as aggregated clumps, but were distributed in a scattered manner. The tumor cells may present different characteristic morphologies in different cases, with different tumor cell smears from the same tumor mass even showing different features. According to the degree of tumor metastasis, changes in myelogram were significantly different. CONCLUSION: The tumor cells of RB patients show unique morphological characteristics in the bone marrow and cerebrospinal fluid. Therefore, correct identification of the cells is of great value in the diagnosis, staging, and prognosis of RB.