Philadelphia chromosome negative acute lymphoblastic leukemia preceding Philadelphia positive chronic myelogenous leukemia

Chronic Myelogenous Leukemia Presenting as a Secondary Malignancy After BCR-ABL1-negative B-lymphoblastic Leukemia/Lymphoma in a Pediatric Patient

Chronic myelogenous leukemia, BCR-ABL1 positive (CML) is a rare myeloproliferative neoplasm in children and presents even less often as a secondary malignancy in the pediatric population. Below, we report a patient with Philadelphia-negative B-lymphoblastic leukemia/lymphoma, who developed CML several years after achieving complete remission, and summarize the existing literature on the clinical and pathologic features of CML as a secondary pediatric malignancy.

Non-treatment-related chronic myeloid leukemia as a second malignancy

The characteristics of the very rare non-treatment-related chronic myeloid leukemia (nTr-CML) cases have never before been analyzed. The literature up to December 2002 was screened using the Medline database to identify cases of Tr-CML and nTr-CML. We considered five cases with nTr-CML identified among 270 newly diagnosed CML at our Department. Our report thus considers nine cases with nTr-CML compared to 77 affected by Tr-CML as a secondary neoplasm. The median age at the appearance of the first tumor was higher in nTr-CML patients compared to that of the Tr-CML group (P<0.0001). The median age at CML diagnosis was significantly higher in the nTr-CML than in the Tr-CML group (P<0.0001). The proportion of hematological malignancies as first tumor type was not different in the two groups (44% in nTr-CML versus 56% in Tr-CML). Our study underlines that nTr-CML as a second malignancy is a rare entity associated with elderly age.