Isolated clonal cytogenetic abnormalities after high-dose therapy

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Therapy-related myeloid neoplasms (t-MN) are known complications of high-dose cytotoxic therapy (HDT).
• The significance of clonal marrow cytogenetic abnormalities (CMCA) after HDT, especially with normal bone marrow pathology, is not well understood.

Purpose of the Study:

• To evaluate the occurrence and significance of CMCA and t-MN in patients treated with HDT.
• To determine if CMCA in the absence of overt t-MN are predictive of developing t-MN.

Main Methods:

• Retrospective analysis of 785 patients treated with HDT (including autologous stem cell transplantation and high-dose cyclophosphamide) between 1997 and 2007.
• Evaluation of t-MN development and isolated CMCA occurrences during the follow-up period.

Main Results:

• Twenty-two patients (3.5% cumulative incidence at 4 years) developed t-MN.
• Eleven patients developed isolated CMCA, with only 20 of these subsequently developing t-MN.
• CMCA were not consistently predictive of t-MN development.

Conclusions:

• In the absence of pathological evidence of t-MN, isolated CMCA should not be considered diagnostic of t-MN.
• Further research is needed to fully understand the implications of CMCA post-HDT.