ABSTRACT
KMT2A gene rearrangements are a major oncogenic driver in multiple hematologic neoplasms. Apart from t(9;11)(p21;q23) (KMT2A/MLLT3) in acute myeloid leukemia (AML), KMT2A gene rearrangements are considered to convey high risk and poor overall survival. Herein, we report a case of a 7 year old boy with newly diagnosed AML and a cryptic KMT2A/AFDN gene fusion resulting from a 5'KMT2A insertional event. The results of conventional chromosome studies revealed trisomy 8 in all 20 metaphases, with normal-appearing chromosomes 6 and 11. A KMT2A break-apart FISH probe identified 2 intact copies of the KMT2A gene region and an extra 5'KMT2A signal in 85% of interphase nuclei. Subsequent FISH studies using a KMT2A/AFDN dual-color dual-fusion FISH probe revealed positive results for a single fusion in 82% of interphase nuclei, indicating a KMT2A/AFDN gene fusion. Subsequently, metaphase FISH confirmed the location of the KMT2A/AFDN fusion at 6q27. To our knowledge, this represents only the second time in the literature that a cryptic KMT2A/AFDN gene fusion resulting from a 5'KMT2A insertional event was reported.
Subject(s)
Leukemia, Myeloid, Acute , Child , Gene Fusion , Humans , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/genetics , Oncogenes , Translocation, Genetic/geneticsABSTRACT
No standardized guidelines exist for infectious prophylaxis following pediatric auto-HSCT. We hypothesized significant variation in clinical practice. Thirty-three Pediatric Transplant and Cell Therapy Consortium centers completed a survey to assess institutional management. The majority utilize viral (91%) and fungal prophylaxis (94%), but duration varies. Bacterial prophylaxis during neutropenia is instituted by 42%. Our study demonstrates marked practice variability in infectious prophylaxis across centers. Additional research is needed to address patterns of infectious complications and to develop meaningful clinical practice guidelines for pediatric auto-HSCT.
