Isochromosome 17q Research Articles

HD-MB03 is a novel Group 3 medulloblastoma model demonstrating sensitivity to histone deacetylase inhibitor treatment

Medulloblastomas are the most common malignant brain tumors in childhood. Emerging evidence suggests that medulloblastoma comprises at least four distinct diseases (WNT, SHH, Group 3 and 4) with different biology, clinical presentation, and outcome, with especially poor prognosis in Group 3. The tight connection of biology and clinical behavior in patients emphasizes the need for subgroup-specific preclinical models in order to develop treatments tailored to each subgroup. Herein we report on the novel cell line HD-MB03, isolated from tumor material of a patient with metastasized Group 3 medulloblastoma, and preclinical testing of different histone deacetylase inhibitors (HDACis) in this model. HD-MB03 cells grow long term in vitro and form metastatic tumors in vivo upon orthotopic transplantation. HD-MB03 cells reflect the original Group 3 medulloblastoma at the histological and molecular level, showing large cell morphology, similar expression patterns for markers Ki67, p53, and glial fibrillary acidic protein (GFAP), a gene expression profile most closely matching Group 3 medulloblastomas, and persistence of typical molecular alterations, i.e., isochromosome 17q [i(17q)] and MYC amplification. Protein expression analysis of HDACs 2, 5, 8, and 9 as well as the predictive marker HR23B showed intermediate to strong expression, suggesting sensitivity to HDACis. Indeed, treatment with HDACis Helminthosporium carbonum (HC)-toxin, vorinostat, and panobinostat revealed high sensitivity to this novel drug class, as well as a radiation-sensitizing effect with significantly increased cell death upon concomitant treatment. In summary, our data indicate that HD-MB03 is a suitable preclinical model for Group 3 medulloblastoma, and HDACis could represent a therapeutic option for this subgroup.

Acute Fulminant Hepatic Failure Due to Hepatosplenic T-cell Lymphoma Mimicking Infiltrative Chronic Myelomonocytic Leukemia

Background: Hepatosplenic T-cell lymphoma (HSTL) was reported as a distinct lymphoma entity by Farcet et al with poor prognosis and almost 100% mortality within 2 years. HSTL commonly presents with pancytopenia. This report describes a rare presentation of a case of HSTL with leukocytosis, acute fulminant hepatic failure and bone marrow picture further confusing with chronic myelomonocytic leukemia (CMML). Case Report: A 58-year-old Caucassian male with mild mental retardation presented with bilateral swelling of lower extremities. Initial blood work-up showed leukocytosis with left-shift, thrombocytosis and elevated liver enzymes. The patient's previous documented blood picture obtained 4-5 years earlier was normal. Preliminary bone marrow biopsy was hypercellular and suggestive of either myelodysplastic syndrome or CMML with a possible progression to acute leukemia. Contrary to the initial suspicion of hepatic infiltration of CMML, ultrasound guided liver biopsy showed leukemic infiltration (Figure) into hepatic sinusoids with minimal cholestasis. Specific immunostaining of bone marrow revealed predominance of CD3+ T cells with negativity for other cell surface markers. Genetic analysis of bone marrow demonstrated trisomy 8 and isochromosome 7q, thus strongly suggesting HSTL. After discussing the prognosis and treatment options, patient and family members opted for hospice care and comfort measures. Conclusion: Hepatosplenic T cell lymphoma although predominantly presents with pancytopenia and thrombocytopenia, could also present with leucocytosis and thrombocytosis. Sinusoidal infiltration of liver with hypercellular marrow should raise a high suspicion of hepatosplenic T cell lymphoma.Figure. CD3: staining of showing T-cell predominance.

Acquired copy number neutral loss of heterozygosity of chromosome 7 associated with clonal haematopoiesis in a patient with Shwachman‐Diamond syndrome

Acquired copy number neutral loss of heterozygosity of chromosome 7 associated with clonal haematopoiesis in a patient with <scp>S</scp>hwachman‐<scp>D</scp>iamond syndrome

Molecular features of hepatosplenic T-cell lymphoma unravels potential novel therapeutic targets

AbstractThe pathogenesis of hepatosplenic T-cell lymphoma (HSTL), a rare entity mostly derived from γδ T cells and usually with a fatal outcome, remains largely unknown. In this study, HSTL samples (7γδ and 2αβ) and the DERL2 HSTL cell line were subjected to combined gene-expression profiling and array-based comparative genomic hybridization. Compared with other T-cell lymphomas, HSTL had a distinct molecular signature irrespective of TCR cell lineage. Compared with peripheral T-cell lymphoma, not otherwise specified and normal γδ T cells, HSTL overexpressed genes encoding NK-cell–associated molecules, oncogenes (FOS and VAV3), the sphingosine-1-phosphatase receptor 5 involved in cell trafficking, and the tyrosine kinase SYK, whereas the tumor-suppressor gene AIM1 (absent in melanoma 1) was among the most down-expressed. We found highly methylated CpG islands of AIM1 in DERL2 cells, and decitabine treatment induced a significant increase in AIM1 transcripts. Syk was present in HSTL cells and DERL2 cells contained phosphorylated Syk and were sensitive to a Syk inhibitor in vitro. Genomic profiles confirmed recurrent isochromosome 7q (n = 6/9) without alterations at the SYK and AIM1 loci. Our results identify a distinct molecular signature for HSTL and highlight oncogenic pathways that offer rationale for exploring new therapeutic options such as Syk inhibitors and demethylating agents.

Early recurrence in standard-risk medulloblastoma patients with the common idic(17)(p11.2) rearrangement

Medulloblastoma is diagnosed histologically; treatment depends on staging and age of onset. Whereas clinical factors identify a standard- and a high-risk population, these findings cannot differentiate which standard-risk patients will relapse and die. Outcome is thought to be influenced by tumor subtype and molecular alterations. Poor prognosis has been associated with isochromosome (i)17q in some but not all studies. In most instances, molecular investigations document that i17q is not a true isochromosome but rather an isodicentric chromosome, idic(17)(p11.2), with rearrangement breakpoints mapping within the REPA/REPB region on 17p11.2. This study explores the clinical utility of testing for idic(17)(p11.2) rearrangements using an assay based on fluorescent in situ hybridization (FISH). This test was applied to 58 consecutive standard- and high-risk medulloblastomas with a 5-year minimum of clinical follow-up. The presence of i17q (ie, including cases not involving the common breakpoint), idic(17)(p11.2), and histologic subtype was correlated with clinical outcome. Overall survival (OS) and disease-free survival (DFS) were consistent with literature reports. Fourteen patients (25%) had i17q, with 10 (18%) involving the common isodicentric rearrangement. The presence of i17q was associated with a poor prognosis. OS and DFS were poor in all cases with anaplasia (4), unresectable disease (7), and metastases at presentation (10); however, patients with standard-risk tumors fared better. Of these 44 cases, tumors with idic(17)(p11.2) were associated with significantly worse patient outcomes and shorter mean DFS. FISH detection of idic(17)(p11.2) may be useful for risk stratification in standard-risk patients. The presence of this abnormal chromosome is associated with early recurrence of medulloblastoma.

Abstract 2499: The significance of Wip1 in neuroblastoma and medulloblastoma

Abstract Background: The most common cytogenetic lesions in the embryonal neural tumors medulloblastoma (MB) and neuroblastoma (NB) affect chromosome 17, with 17q+ or isochromosome 17q, in approximately one-third of MB with these aberrations being a significant indicator of poor clinical outcome. Similarly, in NB 17q+ is the most powerful genetic predictor of adverse clinical outcome. We found aberrations of chromosome 17 in 85% in a national study of NB (PNAS 2010) with 17q+ in 46% and whole 17 gain in 39%. In both MB and NB gain of wild-type p53-induced phosphatase 1 (Wip1) at 17q23 is frequently detected. Wip1 is a serine/threonine phosphatase of the type 2C protein phosphatase family (PP2C). The type 2C phosphatases are linked to the regulation of cellular stress responses. Methods: Comparative genomic hybridization (CGH) with the Affymetrix250k SNP array was used to analyze primary NB and MB and a large set of cell lines. Cell lines from MB, NB and breast cancers were examined for Wip1 expression using western blotting, immunohistochemistry and Real-Time quantitative PCR (Q-PCR). Stable transfections of Wip1 silenced cell lines were generated by shRNA specific for Wip1 and puromycin selection. The phosphorylation of histone H2AX and clonogenicity of Wip1 knockdown were examined in cell lines using flow cytometry and clonogenic assay, respectively. Results: Detailed CGH analysis revealed that Wip1 is present in at least one extra genomic copy in all 54 tumor samples containing 17q gain. Results from our large set of MB and NB cell lines demonstrate 17q aberrations with more complex patterns in MB corroborating previous results in clinical tumors. These findings have been confirmed by analyzing the expression pattern of Wip1 using different immunostaining techniques. Moreover, mRNA levels of Wip1 correlate to Wip1 protein expression. Transfection experiments with shRNA against Wip1 showed substantial decrease in cell viability in MEB-MED8A, D283 MED, D324 MED and SK-N-BE(2) cell lines. MED-MED8A and SK-N-BE(2) showed a significant decrease in cell growth and colony formation. The MB cell lines D283 MED and D324 MED but not MEB-MED8A showed a substantial increase of gamma-H2AX expression after Wip1 knockdown compared to the non-silencing transfections. Conclusions: Our study indicates an important oncogenic role of Wip1 in NB and MB. Our results showed that Wip1 is present in at least one extra genomic copy in the majority of primary NB and MB. We identified NB and MB cell lines expressing high, moderate and low levels of Wip1 where Wip1 knocked cell lines exhibited decreased cell growth and clonogenic capacity compared to non-silenced cells. Moreover, knockdown of Wip1 induced phosphorylation of histone H2AX in NB and MB cell lines indicating a significant role of Wip1 in the DNA damage response of these tumors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2499. doi:1538-7445.AM2012-2499

Clinicopathological features of hepatosplenic T cell lymphoma: a single centre experience from India

In a first series from India, we report 9 cases of hepatosplenic T cell lymphoma (HSTCL) seen in 23 months accounting for 4.2% of all mature T-non-Hodgkin lymphomas (NHLs) in our institution. All patients presented with organomegaly, cytopenias and had evidence of bone marrow involvement. The tumor cells had a blastic (55%) morphology with predominantly intrasinusoidal (33.3%) or intrasinusoidal with an additional interstitial component (33.3%). On flow cytometry, the classical phenotype (CD3+, CD7+, CD4−, CD8−, CD5−, CD56+/−) was seen only in 4 patients. Unusual variations included CD45 (overexpression), CD7 (dim expression), CD3 (overexpression, heterogeneous and dim), CD2 (overexpression), CD5 (heterogeneous), CD8 (heterogeneous or dim or overexpression) and aberrant expression of CD19. Fluoresvent in situ hybridisation (FISH) and karyotyping was abnormal in 5 out of 7 patients evaluated. All of the 5 cases showed abnormalities in chromosome 7 (ring chromosome or isochromosome 7q). Five patients died of disease and related complications in a span of 1–3 months after diagnosis whereas 4 were alive at their last follow up out of which 2 had documented a relapse. In our series, HSTCL was characterized by typical clinical and variable immunophenotypic features and a dismal clinical outcome.

Hematologic Features of Hepatosplenic T-Cell Lymphoma

To the Editor We read with interest the article by Chen and colleagues1 in which they describe the clinical and pathologic characteristics of 7 cases of the rare CD4–/CD8– γδ subtype of T-cell large granular lymphocytic (T-LGL) leukemia. The authors state that 16 cases of CD4–/CD8– γδ T-cell neoplasm had initially been identified, but 9 had been excluded because they represented “various other types of γδ T-cell lymphoma/leukemia involving the blood and bone marrow.”1 It is unfortunate that the data on which these exclusions were made was not provided. This information would have been valuable, especially in determining whether any of the 9 excluded cases were, in fact, hepatosplenic T-cell lymphoma (HSTL), another rare disease with phenotypic similarities with CD4–/CD8– γδ T-LGL leukemia. The data from the resulting 7 cases described in the published series infer that the lack of isochromosome (7q), a feature of HSTL, was a major discriminator, as 6 of 6 tested cases were negative. However, the authors downplay the significance of cytogenetics by only stating that it “may be helpful in difficult cases” in distinguishing between CD4–/CD8– γδ T-LGL leukemia and HSTL. Instead they claim that, although the distinction between these 2 entities can be difficult, it may be readily achieved on morphologic studies and the pattern of splenic and marrow infiltration.1 We want to make particular comment on the …

Case Report Case report of isochromosome 17q in acute myeloid leukemia with myelodysplasia-related changes after treatment with a hypomethylating agent

Isochromosome 17q is a relatively common karyotypic abnormality in medulloblastoma, gastric, bladder, and breast cancers. In myeloid disorders, it is observed during disease progression and evolution to acute myeloid leukemia in Philadelphia-positive chronic myeloid leukemia. It has been reported in rare cases of myelodysplastic syndrome, with an incidence of 0.4-1.57%. Two new agents have been approved for treatment of myelodysplastic syndrome/chronic myelomonocytic leukemia. These are the hypomethylating agents, 5-azacytidine and decitabine, recommended by consensus guidelines for high-risk myelodysplastic syndrome patients not eligible for hematopoietic stem cell transplantation. We present a case of chronic myelomonocytic leukemia with normal cytogenetics at diagnosis treated with decitabine (with good response); however, the patient evolved to acute myeloid leukemia with i(17q) shortly after suspending treatment. To the best of our knowledge, this is the first report of acute myeloid leukemia with myelodysplasia-related changes with i(17q) after the use of a hypomethylating agent.

A Case of Acute Myeloid Leukemia with Bone Marrow Basophilia and Dysmegakaryocytic Hyperplasia with Isochromosome 17q as a Sole Cytogenetic Abnormality: A Clinical Study with Literature Review

A Case of Acute Myeloid Leukemia with Bone Marrow Basophilia and Dysmegakaryocytic Hyperplasia with Isochromosome 17q as a Sole Cytogenetic Abnormality: A Clinical Study with Literature Review

Isolated Isochromosome 17q in Myelodysplastic Syndromes with Pure Red Cell Aplasia and Basophilia

Myelodysplastic syndromes (MDS) with pure red cell aplasia (PRCA) have been shown to be a rare form of MDS. A 35-year-old man presented with pancytopenia: hemoglobin 59 g/L, reticulocytes 2 × 10(9)/L, platelets 33 × 10(9)/L, and leukocytes 1.8 × 10(9)/L with 1% blasts. Bone marrow was hypercellular with 50.4% myeloid cells, 0.0% erythroblasts, 25.4% basophils, and 5.6% myeloblasts. Dysplastic changes including pseudo-Pelger-Huët anomaly of neutrophils and mononuclear micromegakaryocytes were found. Immunohistochemistry with glycophorin C confirmed erythroid aplasia. Cytogenetic analysis showed 46,XY,i(17)(q10)[18]/47,XY,+8[2]. Considering two reported cases, these findings indicate that isolated i(17q) may be implicated in the pathogenesis of MDS with PRCA as a recurrent cytogenetic aberration.

Impact of additional cytogenetic aberrations at diagnosis on prognosis of CML: long-term observation of 1151 patients from the randomized CML Study IV

AbstractThe prognostic relevance of additional cytogenetic findings at diagnosis of chronic myeloid leukemia (CML) is unclear. The impact of additional cytogenetic findings at diagnosis on time to complete cytogenetic (CCR) and major molecular remission (MMR) and progression-free (PFS) and overall survival (OS) was analyzed using data from 1151 Philadelphia chromosome–positive (Ph+) CML patients randomized to the German CML Study IV. At diagnosis, 1003 of 1151 patients (87%) had standard t(9;22)(q34;q11) only, 69 patients (6.0%) had variant t(v;22), and 79 (6.9%) additional cytogenetic aberrations (ACAs). Of these, 38 patients (3.3%) lacked the Y chromosome (−Y) and 41 patients (3.6%) had ACAs except −Y; 16 of these (1.4%) were major route (second Philadelphia [Ph] chromosome, trisomy 8, isochromosome 17q, or trisomy 19) and 25 minor route (all other) ACAs. After a median observation time of 5.3 years for patients with t(9;22), t(v;22), −Y, minor- and major-route ACAs, the 5-year PFS was 90%, 81%, 88%, 96%, and 50%, and the 5-year OS was 92%, 87%, 91%, 96%, and 53%, respectively. In patients with major-route ACAs, the times to CCR and MMR were longer and PFS and OS were shorter (P < .001) than in patients with standard t(9;22). We conclude that major-route ACAs at diagnosis are associated with a negative impact on survival and signify progression to the accelerated phase and blast crisis.

Glioblastoma occurring at the site of a previous medulloblastoma following a 5-year remission period

We describe a case of a 14-year-old boy who developed a cerebellar and brainstem glioblastoma 5 years after treatment for a medulloblastoma. The patient first presented in 2003 with 9 months of vomiting and a 9-kg weight loss. A head MRI showed a heterogeneously enhancing posterior fossa mass with hydrocephalus. Gross total resection was performed and the tumor was consistent with a classic medulloblastoma. Postoperative chemotherapy and craniospinal radiation was administered. The patient remained tumor-free until 2008, at which time he presented with right-sided weakness and numbness, left eye pain, vomiting and weight loss. Imaging showed abnormalities within the posterior pons, medulla, inferior cerebellar peduncles, cerebellar hemispheres and cervicomedullary junction with expansion of the medulla and cervical spinal cord. Due to the location of the lesion, biopsy was felt to be too risky and was avoided. Despite receiving chemotherapy, his symptoms continued to worsen and he died 4 months later. Post mortem examination limited to the brain and spinal cord confirmed the radiographic extent of the tumor. Microscopic examination showed a highly cellular infiltrative glial neoplasm with extensive palisading necrosis. A diagnosis of glioblastoma was rendered. The question of whether the first and second tumors were related is of potential clinical and academic interest. The first tumor was synaptophysin-positive and GFAP-negative, consistent with medulloblastoma. The second tumor was synaptophysin-negative and focally GFAP-positive, consistent with glioblastoma. The glioblastoma displayed EGF receptor amplification, and interestingly, it also displayed MYCN amplification; both tumors showed low level PTEN deletion. The medulloblastoma displayed a signal pattern consistent with an isochromosome 17q, while the glioblastoma showed some cells with an isochromosome 17q signal pattern amid a background of cells with abundant chromosomal instability. The relationship between these two tumors, particularly with regard to various molecular events, is discussed.

Isochromosome 17q, MYC amplification and large cell/anaplastic phenotype in a case of medullomyoblastoma with extracranial metastases

Medullomyoblastoma (MMB) is a rare variant of medulloblastoma, a member of the family of central nervous system (CNS) embryonal tumors. The outcome of standard therapy for CNS embryonal tumors is often unpredictable in the setting of MMB. Here, we present the clinical course and treatment of an almost 4-year-old girl with MMB that was characterized by MYC amplification, isochromosome 17q and large cell/anaplastic histopathology.

Survival Analysis of Additional Chromosomal Aberrations in Philadelphia Chromosome Positive and Negative Cells: A Single Institutional

Abstract 2523 Background:Chronic myeloid leukemia (CML) is a clonal stem cell malignancy associated with the Philadelphia chromosome, t(9;22)(q34q31)/BCR-ABL gene fusion. Additional cytogenetic abnormalities have been known to emerge in Philadelphia (Ph) positive cells (additional Ph+ clones) or Ph negative cells (Ph- clones) at diagnosis, or during or post tyrosine kinase inhibitor (TKI) therapy. Many studies have elucidated that the presence of some Ph+ clones were frequently associated with disease progression, while presence of Ph- clones were unrelated to disease outcome. A majority of studies have shown a waxing and waning of Ph- clonality in response to therapy. However, there remains no solid data regarding overall survival comparing Ph+ and Ph- clones over a long term period. This study focuses on the observation of clonal evolution in various phases of CML, and the relationship to overall survival, disease resistance, kinase domain mutation (KDM) and progression to accelerated or blast phase in patients with CML.Materials and Methods: Data from 318 patients who were diagnosed with CML was retrieved from Moffitt Cancer Center during January 1990-December 2010. Patients are divided into three groups based on the presence of additional ph+ clone (A), ph- clone (B) and absence of both (C). Clinicopathologic results including initial diagnosis date, nature and frequency of clone, copy of clone at karyotyping, disease status in response to treatment and overall outcome were documented and statistically analyzed. All patients with Ph- and Ph+ clones have been treated with TKIs since 2001. Median overall survival and median disease progression survival were compared between conal ph- and clonal ph+ group by the log-rank test. Survival curves were generated using the Kaplan–Meier method. All reported P values are two-sided. Cox Regression (multivariate analysis) was also performed for time to progression. Results:Of 318 (average age 57, range: 19 to 89, M:F=1:1), 17 carried ph- clones (5.3%) and 41 showed additional ph+ clones (12.9%) and the rest (258) lacked additional ph+ or ph- clones. Additional clonal cytogenetic aberrations were random with the most frequent occurrence of trisomy 8 (7 of 17 ph- and 14 of 41 ph+ clones, respectively) and isochromosome 17q (4 in ph+ clone only). There is a higher rate of transformation to accelerated/blast phase in Ph+ additional clones (36.6%,15 of 41) as compared to Ph- additional clone (17.6%, 3 of 17) and Ph+ without additional clones(11.1%, 29 of 260) (p=0.015). The overall median survival is shorter in patients with ph+ clones (133.4 months) than in those with ph- clones (172 months) (p<0.005). KDM were observed in 27 of 110 tested patients (24.5%), and many of them fell into the Ph+ clone group (10 of 22 tested) and fewer into ph- clone group (3 of 10 tested) (p<0.005). Statistical analysis proved that there is a higher rate of transformation to accelerated/blast phase in the presence of a KDM (p<0.005). Of note, most of those with ph- clones had only one episode (59%) with 41% having more than one occurrence and lasting from 6–58 months (average 21.1 months), while in those 41 patients with Ph+ clone; a subset (18 of 41, 43.9%) showed a long-lasting ph+ clone over months (ranging from 2 months to 70 months, average 14.5 months) and the remaining only occurred one occasion (23 of 41, 56.1%). Multivariate analysis for disease progression demonstrated statistical significance with regards to both the ph+ clone and kinase mutation categories (p=0.003 and 0.034). Conclusion:Most Ph+ or Ph- clones are occasionally observed during the long course of CML, with a minor subset of clones showing persistency, especially in Ph- ones. The presence of an additional Ph+ clone is correlated with disease progression, drug resistance and shorter overall survival in comparison to a Ph- clone. A relatively long overall survival is observed in patients with ph- clones. Ph- clones were often identified during disease remission regardless of frequency of clonal copy or clonal persistence. The outcome of patients with concurrent Ph+ and Ph- clones was dictated by the Ph+ clone. Disclosures:No relevant conflicts of interest to declare.

Significance of Bone Marrow Karyotype and Morphology in Patients with Inherited Bone Marrow Failure Syndromes,

Abstract 3431Recurring clonal cytogenetic abnormalities have been described in patients with Fanconi anemia (FA) and Shwachman-Diamond syndrome (SDS). In FA, gains of 3q and monosomy 7 (−7) imply progression to myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). In SDS, isochromosome 7q and deletion (del) 20q are usually benign. Dyskeratosis congenita (DC) and Diamond-Blackfan anemia (DBA) do not have unique clones. We report here the types and frequencies of cytogenetic clones and their association with morphologic MDS or AML in the major inherited bone marrow failure syndromes (IBMFS), in a prospective/ retrospective study of patients with FA, SDS, DC and DBA enrolled in the NCI IBMFS cohort from 2002–2010. Bone marrow (BM) morphology and cytogenetics (G-banding; selected FISH, CGH, SKY) performed at our institute and all outside cytogenetics reports were centrally reviewed. Cytogenetic abnormalities were defined and karyotypes designated according to ISCN (2009). Two independent blinded hematopathologists reviewed BM morphology. Diagnosis of morphologic MDS was based on a modification of WHO 2008 and required ≥10% dysplasia in 2 cell lineages. Data analysis was both cross-sectional and longitudinal. P values are global comparing all 4 disorders using Fisher’s exact test.ParameterAll IBMFSFASDSDCDBAP valueTotal number (N)12835113646–N with clone ever2817 (49%)4 (36%)4 (11%)3 (7%)<0.01N with MDS ever105 (14%)3 (27%)1 (3%)1 (2%)0.01N with clone + MDS75 (14%)2 (18%)00<0.01N with clone alone2112 (34%)2 (18%)4 (11%)3 (7%)<0.01N with MDS alone301 (9%)1 (3%)1 (2%)0.3N with clone at 1st BM179 (26%)4 (36%)3 (8%)1 (2%)<0.01N with clones at follow-up118012<0.01N with follow-up BMs591791716–Median follow-up in years3 (0–19)6 (1–16)2 (1–6)3 (0–19)2 (0–10)–More FA and SDS patients had clones and/or MDS compared with DC or DBA (Table). MDS was always associated with clones in FA but not in the other IBMFS.In FA, bone marrow transplant (BMT) or death occurred with similar frequencies in those with or without clones. Among 17 patients with clones, follow-up cytogenetics were unavailable in 5; of these, 2 with clone alone [one with del 7q and 18p and one with t(3;6)(q?25;p?21)] progressed to AML, while one with clone and MDS died from other causes. Recurring abnormalities in 12 FA patients with clones followed for up to 16 years, included gains of 1q in 4, −7 or del 7q in 3, and deletions of 6p, 13q, 18p and 20q in 2 patients each; only one had gain of 3q. These patients showed fluctuation or disappearance of clones, new appearance of clones, stable clone, or clonal evolution. Progression to MDS occurred with gain of 1q and 6p deletion, gain of 3q, or −7 in 3 patients, respectively; one patient with MDS had clonal persistence. No disease progression was seen in 5 FA patients with clone alone.All 5 SDS patients with clones and/or MDS are alive with no disease progression. The 4 with a clone had stable persistent del 20q as a sole abnormality; 2 had MDS and 2 did not. One had MDS with a normal karyotype.Four DC patients had abnormal clones including 2 with gain of 1q only. One patient with 1q gain died from pulmonary fibrosis. Three others are alive; 2 with stable clones at 7 and 19 years' follow-up, respectively. One additional DC patient has morphologic MDS but no clone.All 3 DBA patients with clones had del 16q, 2 alone and 1 with del 9p; none had MDS. The clones were transient in 2, disappearing within 1–2 years; the third was recently identified. None of these had disease progression. One patient with morphologic MDS alone died from complications of iron overload.This study shows that clonal chromosome abnormalities occur more frequently in FA and SDS than in DC and DBA. Gain of 3q in FA was not as common here as reported by others. This is the first comprehensive study of clones and MDS in DC and DBA. Strengths of this study include the large number of patients, and central review of cytogenetics and morphology. It is unbiased compared with FA literature reports that include many patients referred for BMT. Limitations include a relatively small number of patients with each diagnosis and short follow-up in most. The study demonstrates that clones may fluctuate or disappear, and may not per se portend a bad prognosis. Progression to clinically significant MDS or AML may be related to the severity of cytopenias and not to clone alone, and warrants more extensive long-term studies. Disclosures:No relevant conflicts of interest to declare.

Myeloid neoplasms with isolated isochromosome 17q represent a clinicopathologic entity associated with myelodysplastic/myeloproliferative features, a high risk of leukemic transformation, and wild-type TP53.

Isolated isochromosome (17q) is a rare cytogenetic abnormality in Philadelphia chromosome-negative myeloid neoplasms, usually myelodysplastic and/or myeloproliferative neoplasms (MDS/MPN). De novo acute myeloid leukemia (AML) with isochromosome 17q has rarely been reported. The frequency of genetic mutations is unknown. The authors assessed clinicopathologic, immunophenotypic, and molecular genetic features of 22 myeloid neoplasms with isolated isochromosome 17q. Fourteen patients presented as MDS/MPN; 8 as de novo AML. Most presented with leukocytosis, anemia, thrombocytopenia, and splenomegaly. Morphologically, all showed myelodysplastic and myeloproliferative features, including pseudo-Pelger-Huet-like neutrophils, micromegakaryocytic hyperplasia, hypercellularity, fibrosis, and osteosclerosis. Blasts were increased (median, 40% in de novo AML; 9% in MDS/MPN). Immunohistochemical assessment of proliferation and apoptosis rates in AML were similar to a matched group without isochromosome 17q. In most patients, isochromosome 17q occurred at time of blast transformation or disease progression. DNA sequencing revealed no mutation in the uninvolved TP53 allele. Mutational analyses showed rare mutations in NRAS (3 of 10), FLT3 (2 of 16), and JAK2 (1 of 18), and no mutations in NPM1 (0 of 15), KIT (0 of 4), and CEBPA (0 of 4). The median overall survival was 14.5 months for de novo AML, and 11.0 months for MDS/MPN. With a median follow-up of 8.5 months (range, 1.5-107 months), 15 died of disease, 6 had persistent disease, and 1 was in remission after bone marrow transplantation. The authors conclude that myeloid neoplasms with isolated isochromosome 17q represent a distinct clinicopathologic entity with myelodysplastic and myeloproliferative features, high risk of leukemic transformation, and wild-type TP53.

Relapsed hepatosplenic T-cell lymphoma heralded by a solitary skin nodule

Hepatosplenic T-cell lymphoma (HSTL) represents a rare form of peripheral T-cell lymphoma composed of lymphocytes that typically express the γδ T-cell receptor. This form of lymphoma rarely involves the skin. We report the case of a 23-year-old man with a history of HSTL that was presumed to be in remission who presented with a solitary cutaneous nodule. Skin biopsy showed an atypical lymphocytic infiltrate arranged in a perivascular and periappendageal pattern with associated vacuolar epidermal interface change. The constituent T cells expressed CD2, CD3, CD7, CD8, β-F1, γδ T-cell receptor, Tia-1 and granzyme B. The cells lacked the expression of CD4, CD5 and CD56. Fluorescence in situ hybridization (FISH) showed a characteristic chromosomal abnormality, namely isochromosome 7q, which confirmed the diagnosis of cutaneous HSTL. On restaging his disease, widespread progression was noted. To our knowledge, this report provides the first detailed account of cutaneous involvement by HSTL. We show the novel utility of FISH to identify isochromosome 7q in the lesional skin of HSTL patients.

Prenatal Diagnosis of Alobar Holoprosencephaly, Cyclopia, Proboscis, and Isochromosome 18q in the Second Trimester

We would like to present a rare case of alobar holoprosencephaly (HPE) in a fetus diagnosed by routine sonography in the second trimester. Structural sonography demonstrated multiple facial anomalies including absent nasal bone, flat facial profile, hypotelorism, fusion of the orbits and proboscis. After counseling, termination of pregnancy was performed by vaginally administered misoprostol. Karyotyping of amniotic fluid cells revealed an isochromosome 18q, resulting in a trisomy 18q and monosomy 18p. A stillborn female of 390 g with several congenital anomalies was born. Postmortem examination demonstrated several anomalies including the HPE, cyclopia, double fused eye, absence of the nose, and the presence of a proboscis. In the literature only a few cases have been published.

Prenatal diagnosis and molecular cytogenetic characterization of a derivative chromosome der(18;18)(q10;q10)del(18)(q11.1q12.1)del(18)(q22.1q22.3) presenting as apparent isochromosome 18q in a fetus with holoprosencephaly

Objective To present prenatal diagnosis and molecular cytogenetic characterization of a derivative chromosome der(18;18)(q10;q10)del(18)(q11.1q12.1)del(18)(q22.1q22.3). Materials, Methods, and Results A 32-year-old woman was referred for genetic counseling of prenatally detected isochromosome 18q [i(18q)]. She had undergone amniocentesis at 19 gestational weeks because of a trisomy 18 risk of 1/39 derived from abnormally low levels of maternal serum unconjugated estriol, inhibin A, α-fetoprotein, and total β-human chorionic gonadotropin. Amniocentesis revealed a karyotype of 46,XX,i(18)(q10). Parental karyotypes were normal. Prenatal ultrasound showed alobar holoprosencephaly. Repeated amniocentesis was requested and performed at 21 gestational weeks. Array-comparative genomic hybridization analyses revealed a 14-Mb deletion of 18p11.32-p11.21, a 37.8-Mb duplication of 18q12.1-q22.1, and a 6.9-Mb duplication of 18q22.3-q23. Metaphase fluorescence in situ hybridization study showed the absence of an 18q12.1-specific probe signal in one arm and the absence of an 18q22.2-specific probe signal in the other arm of the derivative chromosome. Quantitative fluorescent polymerase chain reaction analysis determined a paternal origin of the derivative chromosome. The cytogenetic result was 46,XX,der(18;18)(q10;q10)del(18)(q11.1q12.1)del(18)(q22.1q22.3). The fetus postnatally manifested cebocephaly. Conclusion Concomitant monosomy 18p and trisomy 18q can be associated with holoprosencephaly and abnormal maternal serum screening results. Array-comparative genomic hybridization, fluorescence in situ hybridization, and quantitative fluorescent polymerase chain reaction are useful in genetic counseling of prenatally detected isochromosomes by providing information on the origin and genetic components of the isochromosome.