Search

Key Clinical Message We report two male siblings with SDS. They have the same compound heterozygous mutations. Only one of the siblings acquired cytogenetic abnormality of i(7q) 2 years after diagnosis, became transfusion‐dependent, and underwent allogeneic hematopoietic stem cell transplantation. These cases indicate that i(7q) is associated with significant cytopenia in SDS patients.

Summary The definition of the myelodysplastic syndrome (MDS) subtype ‘MDS with isolated del(5q)’ was expanded to include cases with one additional non-chromosome 7 based cytogenetic abnormality in the 2016 revised World Health Organization classification. This study applied the revised definition to a large primary MDS cohort, and evaluated the prognostic impact of the additional cytogenetic abnormality. Seventy-two of 1067 patients (7%) met the ‘MDS with isolated del(5q)’ criteria, 11 (1%) of whom had an additional cytogenetic abnormality. There was no survival difference between patients in whom del(5q) occurred alone, compared to those with one additional cytogenetic abnormality (P = 0·52).

Translocations involving MYC are highly characteristic for Burkitt lymphoma (BL). BCL2 expression has also been found previously in about 10 to 20% of BL cases, and BCL2 translocation is a major mechanism for the deregulation of BCL2 expression in non-Hodgkin lymphomas. However, we know little about the incidence of MYC/BCL2 double-hit (DH) in BL. We examined BL cases to determine how frequently they contained BCL2 translocations in combination with MYC translocations using fluorescence in situ hybridization. We also determined the effect of BCL2 expression on clinical outcomes of BL. BCL2 translocations were detected in 3.5% (2/57 cases) of the cases, and BCL2 expression was detected in 33%. Two cases with BCL2 translocation also showed BCL2 expression. The incidence of BCL2 expression was significantly higher in patients 16 years of age and older (46%) than in patients under 16 years of age (6%). Among patients 16 years of age and older, we did not detect significant differences in overall survival with respect to BCL2 expression status. In conclusion, BCL2 translocation is a rare cytogenetic abnormality in BL, and BL probably accounts for only a small fraction of MYC/BCL2 DH lymphomas. BCL2 expression in BL is probably not associated with BCL2 translocations.

We report 23 consecutive pediatric patients with MDS who received allogeneic HSCT on IRB approved protocols between 1992 and 2009 at Children's Memorial Hospital (Chicago, IL). Nine patients had de novo MDS, whereas 14 patients had treatment-related MDS. All patients had a documented cytogenetic abnormality, and monosomy 7/7q- was seen in 12 patients (52%). Fourteen of 23 patients received a myeloablative conditioning regimen; RIC regimens were used for the remaining nine. Five patients relapsed post-transplant, including four patients who received RIC transplant and four patients with treatment-related MDS. For the entire group, estimated five-yr RFS and OS were 47% and 50%, respectively. Treatment-related MDS was associated with decreased RFS in comparison with de novo MDS (33% vs. 70%, p = 0.05). Five-year OS rates reached 80% for those with de novo MDS. RIC regimens were associated with decreased three-yr RFS in comparison with myeloablative regimens (22% vs. 68%, p = 0.02). There was no correlation of survival with blast count at diagnosis, IPSS score, cytogenetic abnormality, donor type, or HLA match. Larger series are needed to confirm prognostic factors so that higher-risk patients can be targeted with novel approaches.

Clinical descriptions of individuals with partial deletion of the distal short arm of chromosome three have been reported rarely. A characteristic phenotype has been proposed. We present another patient with this cytogenetic abnormality whose physical and developmental features show similarities with, as well as differences from, previously reported cases. This suggests that the clinical phenotype requires further definition. In addition, gene dosage studies were undertaken on several serum proteins in order to try to map the location of the responsible genes on chromosome three.

Clinical course and cytogenetic analysis suggest that myelodysplasia (MDS) is one step in a multistep model of malignant transformation of haematopoietic stem cells to acute myeloid leukaemia (AML). We report a further case of MDS associated with trisomy 2, and comment on the significance of the cytogenetic abnormality, which as a sole abnormality only occurs in MDS, but is found in combination with other chromosomal abnormalities in AML. Previous reports on balanced and unbalanced chromosomal abnormalities associated with therapy related MDS and therapy related AML suggest that trisomy 2 is an early chromosomal abnormality in leukaemogenesis.

The phenotypes of a mother and child with a duplication of 7p15-7p22 are described. The mother is mosaic for the cytogenetic abnormality, whereas all cells are affected in her son. Fewer than 5 patients with interstitial 7p duplications are described in the world literature whereas over 30 phenotypic descriptions of individuals with terminal 7p duplication can be found. Authors have suggested that the associated phenotype amounts to a recognizable syndrome. The current cases give further insights into the phenotype that results from pure 7p duplication, both in its mosaic and in its full form. Comparisons are made with previous cases, in the light of the shorter segment involved in the current patients, whose duplication does not extend to pter. This case description will be useful in counseling patients with duplications of 7p and lends support to the existence of characteristic craniofacial features and congenital malformations in this chromosome rearrangement. In addition, as earlier case reports all describe the phenotype associated with non-mosaic partial 7p trisomy, the current observations amount to clear evidence that mosaicism attenuates the phenotype of this rearrangement.

We describe a 19-year-old patient with a de novo mosaic add(3) chromosome (extra material of unknown origin on the 3q). The use of spectral karyotyping and fluorescence in situ hybridization using subtelomeric probes permitted the full characterization of the cytogenetic abnormality. The additional material on 3q was found to originate from 14q31-qter. This is one of the few reported cases with trisomy 14q31-qter and is the first mosaic case.

We report on a 4-year-old girl with obesity and hyperphagia whose peripheral blood cytogenetic analysis showed mosaicism for a deletion of band 1p36.33. Terminal 1p deletions are rarely reported and this patient represents the first identified case of mosaicism. Given the subtlety of the cytogenetic abnormality and the possibility of mosaicism, the incidence of such deletions has probably been underestimated. While a characteristic phenotype associated with this karyotypic abnormality was described recently, the present report highlights the additional clinical findings of obesity and hyperphagia and the overlap of manifestations with Prader-Willi syndrome.

We present a patient with deletion of IgH associated with the reciprocal translocation (8;14) in Burkitt lymphoma. The patient had treatment resistant disease and died 10 weeks after diagnosis. The deletion was detected by fluorescence in situ hybridization at diagnosis and again after failure of chemotherapy. To our knowledge this is the first report of such a deletion.

A family is described in which three, and possibly four members, namely, the propositus, two paternal uncles, and possibly his paternal grandfather, developed a myelodysplastic syndrome (MDS) after the age of 60 years. This late onset resembles sporadic cases which are commoner in older age, rather than the previously reported familial cases most of whom have been children or young adults. The three affected members had megaloblastoid bone marrows with an increased proportion of bone marrow blasts and developed progressive bone marrow failure without leukemic transformation. The propositus showed a dramatic but temporary response to GM-CSF therapy but eventually became unresponsive with a marked increase in bone marrow reticulin and reduction in hemopoietic elements. Affected members had no recognisable bone marrow cytogenetic abnormality but the pattern of inheritance and similarity in clinical features suggest an inherited genetic defect which predisposes to the development of MDS.

Fragile X syndrome is a common condition resulting from a cytogenetic abnormality in the X chromosome. Mental retardation, characteristic facies, and large testes are some of the most important characteristics of the condition. The relatively high incidence of the syndrome--approximately one per thousand--the high incidence of cardiac anomalies in these individuals, the oral and facial features associated with the condition, and the paucity of reported cases in the dental literature make it particularly interesting to dentistry. Here we report the case of a 12-year-old male, including the cytogenetic and cephalometric analyses, presenting with some of the classic features and some features not commonly reported.

We report on a newborn boy with a de novo inverted interstitial duplication of chromosome 8(q13----q24.1). This form of cytogenetic abnormality, in which a mirror image interstitial duplication has occurred, is exceedingly rare. Review of the literature and mechanisms to explain the origin of this type of chromosome aberration are presented. A review of the findings from individuals with partial dup(8q) demonstrate remarkable similarity to the infant we describe.

Opsoclonus-myoclonus (OM) is a paraneoplastic syndrome of probable autoimmune origin. Despite current therapies aimed at decreasing autoantibody formation, OM is difficult to control and may impact long-term neurologic outcome. We present a case of a 19-month-old patient who initially presented with OM, neuroblastoma and a constitutional cytogenetic abnormality t(5;12)(q11.2;q15). The patient's OM was recalcitrant to conventional therapies, but showed significant improvement following treatment with rituximab.

We report a patient with the Killian/Teschler-Nicola/Pallister mosaic syndrome in association with a cytogenetic abnormality. This patient is the first reported to have lymphocyte mosaicism for an isochromosome of 12p. All other patients with the Killian syndrome have had normal lymphocyte karyotypes, although mosaicism for a similar isochromosome of 12p has been reported in the fibroblasts of most patients with the Killian syndrome.