Development of plasma cell myeloma in a B-cell chronic lymphocytic leukemia patient with chromosome 12 trisomy

CD5+ B lymphoproliferative disorder with subsequent development of plasma cell leukaemia: Diagnostic and aetiologic reasoning

BACKGROUND

Plasma cell myeloma (PCM) has been sporadically reported to occur simultaneously or subsequently to mature B lymphoproliferative disorders (LPDs), predominantly chronic lymphocytic leukaemia (CLL).

METHODS

We describe the clinical and laboratory findings of a 69-year-old male patient who developed plasma cell leukaemia (PCL) 8 years after an initial diagnosis of a low stage CD5+ B LPD and 3 years after treatment for LPD.

RESULTS

The transition from a clinically indolent B LPD to an aggressive PCM was documented by bone marrow (BM) biopsy, while flow cytometric (FC) immunophenotyping conferred additional information by disclosing the co-existence of both disorders in BM and the presence of abnormal monotypic PCs in peripheral blood above PCL levels. Phenotypic findings suggested a discrete clonal origin of the two disorders.

CONCLUSIONS

This report of PCL development in a patient with residual CD5+ B LPD, emphasizes the need for comprehensive diagnostic evaluation of such cases and scrutiny of their aetiological relationship, including FC immunophenotyping due to its high analytical sensitivity and multiparametric capacity compared to morphology or immunohistochemistry alone. © 2017 International Clinical Cytometry Society.

Establishment and characterization of a novel osteosarcoma cell line: CHOS

Osteosarcoma has a well-recognized bimodal distribution, with the first peak in adolescence and another in the elderly age-group. The elderly patients have different clinical features and a poorer prognosis as compared to adolescents. To better understand the biological features of osteosarcoma in the elderly population, we established a new human osteosarcoma cell line from a 58-year-old man with primary chondroblastic osteosarcoma. After 6 months of continuous culture in vitro for over 50 passages, an immortalized cell line CHOS was established. The cell line was well-characterized by cytogenetic, biomarker, functional, and histological analyses. The CHOS cells exhibited a spindle-shaped morphology and a doubling time of 36 h. Cytogenetic analysis of CHOS cells revealed the loss of chromosome Y and the gain of chromosome 12. Quantitative real-time polymerase chain reaction (RT-PCR), Western blotting and/or immunofluorescence revealed the expression of chondroblastic, mesenchymal and tumor metastasis markers in the CHOS cells. Compared with the osteosarcoma cell line, the CHOS cells were found to be more sensitive to cisplatin and doxorubicin, but were resistant to methotrexate. The cell line was highly tumorigenic and maintained the histological characteristics and invasive nature of the original tumor. Furthermore, on immunohistochemical analysis, the xenografts and metastases were found to co-express collagen II, aggrecan, vimentin and S100A4 that resembled the original tumor cells. Our results indicate, the potential of CHOS cell line to serve as a useful tool for further studies on the molecular biology of osteosarcoma, especially in the elderly patients. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2116-2125, 2016.