A Case of a Patient with Therapy-related Core Binding Factor (CBF) Acute Myeloid Leukemia (CBF-AML).

OBJECTIVES: Identifying therapy-related AML (t-AML) of newly diagnosed acute leukemias is of great interest. Development of t-AML can occur after cytotoxic chemotherapy and/or radiation. We report a case of t-AML with CBFB::MYH11 fusion in a patient with a distant history of treated stage IIIB nodular sclerosing Hodgkin's lymphoma. We present the clinical course of the patient and the methods used to detect and monitor the rearrangement. Core binding factor AML (CBF-AML) after exposure to treatment is considered to be a good prognostic marker. The identification of these favorable AML subtypes such as CBF-AML highlights the importance of identifying genetic alterations, especially with increasing incidences of t-AML due to changes in choice of treatment and prognosis.

An Isochromosome 9q: A Rare Event in Pediatric B-ALL.

OBJECTIVES: B-cell acute lymphoblastic leukemia (B-ALL) is one of the most common leukemias affecting the pediatric population. It represents ~25% of cancer diagnoses among children. Specific genetic changes predict the prognosis in B-ALL with recurrent genetic changes. Here we present a case report of a 20-year-old male with B-ALL. The patient presented with acute onset worsening upper extremity pain with pallor, weight loss, dizziness, fatigue, and abnormal complete blood count (CBC). Conventional cytogenetics showed a karyotype of 46,XY,add(9)(q13),i(9)(q10)[19]. DNA FISH analysis performed on the bone marrow showed hemizygous deletion of the 9p21(CDKN2A) in 15.5% of the nuclei examined. The presence of an isochromosome 9q [i(9)(q10) is a rare event in pediatric B-ALL. An isochromosome 9q occurs in 0.6% of the patients studied in the literature. The significance of this abnormality in pediatric B-ALL is not clear. Profiling cases like this to understand the molecular mechanisms of rare chromosomal abnormalities and rare mutations in children with B-ALL could help us to better treat them.

A rare case of B-lymphoid blast phase of chronic myeloid leukemia: Diagnostic challenges.

Chronic myeloid leukemia(CML) is characterized by Philadelphia(Ph) chromosome. About 5% of cases are diagnosed in blast phase. We report a case of a 53-year-old female with no significant medical history, in B-lymphoblast crisis. Flow cytometry demonstrated B-lymphoblasts with no myeloid aberrancies, together with immature neutrophils in blood, and B-lymphoblasts in bone marrow. Cytogenetic studies identified Ph+ with complex abnormalities. Molecular analysis showed positive both for p210 and p190 transcripts in blood. ABL1 mutation analysis by Next Generation Sequencing(NGS) detected Thr315Ile mutation, which confers resistance to many tyrosine kinase inhibitors(TKIs). Eight months later she received allogeneic transplant and is doing well.

A rare case of near-haploid acute lymphoblastic leukemia.

Near-haploid acute lymphoblastic leukemia is seen in <1% of cases and carries an unfavorable prognosis. We report a case in an 18-year old male. He presented with two abnormal clones, one with 27-28 and one with 54-56 chromosomes. Near-haploidy (27-28) carries a poor prognosis and hyperdiploidy (>50) has a good prognosis. The correct diagnosis was critical for this patient's prognosis and treatment. The patient achieved remission after a bone marrow transplant from a 10/10 HLA matched sibling donor. He relapsed six months later and expired seven months later. This case illustrates the need for careful standard and molecular cytogenetic analysis for accurate diagnosis and treatment for this rare type of ALL.

Anti-CD19 chimeric antigen receptor targeting of CD19 + acute myeloid leukemia.

Aberrant expression of CD19 in acute myeloid leukemia (AML) is commonly associated with t(8;21)(q22;q22), although AML cases lacking this translocation occasionally express CD19. Mixed-phenotype acute leukemia also frequently expresses CD19. Chimeric antigen receptor (CAR) technology is a major breakthrough for cancer treatment, with the recent approval of CD19-directed CAR (CD19CAR) for treating B-cell malignancies. However, little information exists on using CD19CAR for other CD19 positive neoplasms such as AML. Our findings indicate that CD19CAR therapy can potentially be used for those with mixed phenotype leukemia and a subset of AML cases.

IGH amplification in patients with B cell lymphoma unclassifiable, with features intermediate between diffuse large B cell lymphoma and Burkitt's lymphoma.

B cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma (DLBCL) and Burkitt's lymphoma (BL) (B-UNC/BL/DLBCL) is a new category of tumors that have features resembling both DLBCL and BL. These tumors have large and medium sized cells with greater irregularity of nuclei and more prominent nucleoli than BL. Approximately 35% to 50% have C-MYC rearrangements, although half are non-immunoglobulin variants. We identified six cases of B-UNC/BL/DLBCL with low-level IGH amplification. Four patients died with a median survival of 7 months (range, 6-20). In conclusion, to our knowledge low-level IGH amplification has not been previously described and should be evaluated for in this patient population.

Lymphoproliferative disorder that resembles heptosplenic lymphoma during maintenance treatment for T-cell acute lymphoblastic leukemia.

A 6-year-old male presented with a testicular mass, hepatosplenomegaly, and a pleural effusion while undergoing maintenance chemotherapy for treatment of T-cell acute lymphoblastic leukemia (T-ALL). He was subsequently diagnosed with a lymphoproliferative disorder that resembled hepatosplenic lymphoma (HSL). While the extranodal presentation and the protracted yet aggressive clinical course are consistent with HSL, the findings of monosomy 8 and polymorphic cell populations are unique and have not been previously described in this type of lymphoma.

Cytogenetic evaluation: a primer for pediatric nurse practitioners.

Patients with genetic disorders require specific types of cytogenetic testing for accurate diagnosis and prognosis followed by prompt treatment. This primer will serve as a guide for pediatric nurse practitioners on the use of various cytogenetic testing for the diagnosis of genetic disorders. Knowledge of the latest cytogenetic technologies will facilitate diagnosis and counseling related to genetic abnormalities such as inherited disorders, mental retardation, developmental delay, and autism. This reference will enable pediatric nurse practitioners to help identify patients with various inherited genetic disorders and provide subsequent monitoring and treatment.

Pediatric T-cell prolymphocytic leukemia with an isolated 12(p13) deletion and aberrant CD117 expression.

T-cell Prolymphocytic leukemia (T-PLL) is a rare post-thymic T-cell malignancy that follows an aggressive clinical course. The classical presentation includes an elevated white blood cell (WBC) count with anemia and thrombocytopenia, hepatosplenomegaly, and lymphadenopathy. T-PLL is a disease of the elderly and to our knowledge it has never been described in the pediatric age group. We report a case of T-PLL in a 9 year old male who was initially diagnosed with T-cell acute lymphoblastic lymphoma (ALL), the diagnosis was later refined to T-PLL following additional analysis of bone marrow morphology and immunophenotype. Two unusual findings in our patient included CD117 expression and an isolated chromosomal 12(p13) deletion. The patient failed to respond to standard ALL induction chemotherapy, but achieved complete remission following treatment with a fludarabine and alemtuzumab-based regimen.

Myelofibrosis involving lymph node: a novel cytogenetic abnormality in a mimicker of mesenchymal neoplasm.

A case of primary myelofibrosis involving lymph node and with a novel cytogenetic abnormality [del (18) (p11.2-3)] is reported. The abnormalities are identical among specimens from the lymph node, peripheral blood, and bone marrow that were analyzed years apart. Additionally, we show that the infiltrate by dysplastic megakaryocytes in the lymph node morphologically mimics a metastatic mesenchymal neoplasm, even when the clinical history myelofibrosis was known.

Ovotesticular disorder of sexual development (true hermaphroditism).

OBJECTIVES: To determine the mechanism for the 46,XX/46,XY karyotype observed in a patient with an ovotesticular disorder of sexual development (ie, true hermaphroditism). METHODS: Cytogenetic, molecular cytogenetic, and molecular DNA analyses were performed on the blood, skin, and left and right gonadal tissue from 2 surgical procedures. The results of these studies were used to determine whether the ovotesticular disorder of sexual development resulted from mosaicism or tetragametic chimerism. RESULTS: Cytogenetic and molecular analyses revealed a mixture of 46,XX and 46,XY cells in most tissues. DNA analysis from the gonadal tissues from surgeries 1 and 2 was performed. Highly polymorphic loci from 12 different chromosomes were examined for the presence of > or = 1 paternal or maternal alleles. Three loci were highly informative: D14S544 (14q32.2), DS14S583 (14q21.3), and SE33 (6q14). Each demonstrated the presence of 2 paternal and 2 maternal alleles, indicating that the ovotesticular disorder of sexual development resulted from tetragametic chimerism. CONCLUSIONS: Based on the findings of the cytogenetic, molecular cytogenetic, and DNA analyses of the polymorphic markers from several different loci, it was confirmed that the patient had tetragametic chimerism. This case has assisted in increasing our knowledge of the possible mechanisms causing this rare and complex disorder.

Prenatal diagnosis of trisomy 3 mosaicism.

OBJECTIVES: To present the clinical, cytogenetic, and molecular cytogenetic findings of prenatally diagnosed trisomy 3 mosaicism. CASE AND METHODS: Trisomy 3 mosaicism is rare, and only two cases of prenatally diagnosed trisomy 3 mosaicism have been reported. Amniocentesis, performed for AMA, revealed a karyotype of 47,XX, + 3[8]/46,XX[27]. Periumbilical blood sampling (PUBS) showed 46,XX in 100 cells. Fluorescence in situ hybridization (FISH) analysis using an alpha satellite chromosome 3 probe confirmed the cytogenetic findings. A repeat amniocentesis confirmed mosaicism for trisomy 3 (47,XX, + 3[1]/46,XX[18]). The infant was delivered by elective C-section because of the presence of IUGR and oligohydramnios. The baby had normal physical findings at birth except for symmetric IUGR, apparently resulting from the placental trisomic cell lines. At delivery, chromosome analysis of 50 cells each from blood, placenta, and umbilical cord revealed 46,XX in all cells. FISH analysis of amniotic fluid cells (54 nuclei), peripheral blood (50 nuclei), umbilical cord fibroblasts (57 nuclei), and placental tissue (52 nuclei) demonstrated two signals in 200 nuclei (i.e., 46,XX) and three signals in 13 nuclei (i.e., 47,XX, + 3). At 11 months of age, the baby was progressing normally. CONCLUSION: A diagnosis of trisomy 3 mosaicism is problematic for patients and clinicians. This is only the third case of trisomy 3 mosaicism identified at amniocentesis. Ultrasound, PUBS, and evaluation of placental tissues and postnatal peripheral blood, were useful in providing information regarding the fetal involvement of trisomy 3. Additional cases of prenatally diagnosed mosaicism for rare trisomies are necessary to more accurately assess the significance of these findings.

Prenatal diagnosis of a rare inherited heterochromatic variant chromosome 4.

Heterochromatic chromosome polymorphisms have been extensively reported. Most are associated with C-band positive regions located on chromosomes 1, 9, 16, and Y. We report a prenatal case of a rare heterochromatic variant on chromosome 4. Amniocentesis was performed on a 35-year-old white female for AMA. The karyotype was 46,XY,add(4)(q35)?. One chromosome 4 homolog had an additional dark band at the terminus of the long arm. Parental chromosome analyses revealed that the chromosome 4 was maternally inherited. The mother and fetus were both Q and C-band positive and NOR and DAPI Distamycin staining negative. FISH using Y, 4, and 9 whole chromosome paint (WCP), centromere probes for all chromosomes (Cytocell, Chromoprobe Multiprobe-I System, Rainbow Scientific, Inc., Windsor, CT), alpha-satellite probes for 13/21, 14/22 (D13Z1/D21Z1; D14Z1/D22Z1, Oncor, Gaithersburg, MD), and the 15 PWS/Angelman probe (LSI SNRPN, D15Z1, PML, Vysis, Inc., Downers Grove, IL) were negative. The TelVysion 4q telomere probe (D4S2930, Vysis, Inc.) was positive. A phenotypically normal male was born at 37 weeks. Follow up studies on placenta, cord, cord blood, and foreskin confirmed the prenatal results. Based on these findings, it appears that this chromosome 4 was a rare heterochromatic variant. Heterochromatic variants have been demonstrated to have no phenotypic effect on carriers. This case illustrates the importance of reporting unusual variant chromosomes for genetic counseling purposes. To the best of our knowledge, this is the first report of a heterochromatic variant involving part of the long arm of chromosome 4 in a phenotypically normal mother and child.