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Routine bone marrow cytogenetics in initial staging of lymphoma
ABSTRACTS
conditions that mimic the lymph node tumour microenvironment. Flow cytometry and western blotting were used to investigate effects on apoptosis induction, cell cycle progression, cell proliferation and intracellular signalling. MK2206 induced apoptosis in a dose dependent manner and was significantly more cytotoxic than idelalisib. We observed a greater-than-additive effect of binimetinib in combination with MK2206, suggestive of synergy. No synergy between binimetinib and idelalisib was observed. Interestingly, we observed an increase in AKT phosphorylation in response to binimetinib which was blocked by MK2206 but not idelalisib. Our data suggest that dual inhibition of MEK1/2 and AKT may be highly effective against CLL cells. The ineffectiveness of combining binimetinib with idelalisib suggests that the effects observed are independent of PI3-kinase d. Dual inhibition of MAPK-ERK1/2 and AKT signalling may be effective at targeting the proliferative/drug-resistant compartment of CLL that resides in the tumour microenvironment. ROUTINE BONE MARROW CYTOGENETICS IN INITIAL STAGING OF LYMPHOMA Charles J. Shuttleworth1, Robyn Lukeis2, Joanne E. Joseph1 1 Haematology Department, St Vincent’s Hospital, Sydney, and 2 Cytogenetics Department, St Vincent’s Hospital, Sydney, NSW, Australia Aim: To assess the utility of conventional cytogenetic analysis of bone marrow aspirates in initial staging of lymphoma. Method: Bone marrow aspirates performed during initial staging of lymphoma were reviewed at a single institution from 1/1/15 to 31/12/15. Fifty included a request for conventional cytogenetics. For each case, data was collected on: indication, final diagnosis, results of aspirate, trephine, flow cytometry and conventional cytogenetics, as well as whether diagnosis had been aided via other specimens. Results: Eight abnormalities were noted in seven of 50 cases (14%). Three of the abnormalities related to an age related loss of Y chromosome (non-pathogenic). One was a complex karyotype in a case with diffuse large B cell lymphoma. One was a hyperdiploid clone found in a case whose trephine displayed diffuse involvement with a T cell lymphoma. Two samples demonstrated a t(11;14) and were morphologically involved with mantle cell lymphoma (MCL). In both cases preceding lymph node biopsy had already established this diagnosis. None of these abnormalities changed the diagnoses or management in their respective cases. Discussion: A conventional karyotype appears to have a limited diagnostic and prognostic utility in the staging of lymphoma, and its routine ordering should be reviewed. SPONTANEOUS TUMOUR LYSIS SYNDROME AS AN UNUSUAL PRESENTATION OF B LYMPHOBLASTIC LEUKAEMIA/LYMPHOMA WITH PROMINENT HAEMOPHAGOCYTOSIS Fiona Swain, Louise Seymour, Bronwyn Williams Haematology Department, Pathology Queensland, Royal Brisbane and Women’s Hospital, Qld, Australia
S111
Background: Tumour lysis syndrome (TLS) is a serious complication of rapid cell death. It is mostly encountered following treatment of malignancies with high proliferative indices; however, spontaneous TLS has been described in haematological and non-haematological malignancies. We describe a case of paediatric B lymphoblastic leukaemia/lymphoma with spontaneous TLS and marked haemophagocytosis within the bone marrow. Case study: A 2-year-old girl presented with fever and irritability. Examination revealed splenomegaly. Initial investigations showed pancytopenia, multi-organ dysfunction and biochemical derangements consistent with TLS. Occasional blasts were seen on a blood film. A bone marrow aspirate and trephine was performed. There was a heterogenous population of lymphoblasts on the aspirate accounting for 19% of cells. Scattered histiocytes were evident. The trephine specimen was markedly hypocellular with a small infiltrate of blasts. Histiocytes accounted for most cells with prominent haemophagocytosis. Immunohistochemical profile of the blast population (interstitially and within histiocytes) was consistent with B lymphoblasts. Flow cytometry demonstrated an immunoprofile consistent with B lymphoblasts. Cytogenetic and molecular studies were unremarkable. Discussion: Classically, B lymphoblastic leukaemia/lymphoma demonstrates a hypercellular marrow with peripheral blood leucocytosis. In this unusual case, haemophagocytosis accounts for the hypocellularity of the marrow and would have contributed to the spontaneous TLS. DETECTION OF EARLY T CELL PRECURSOR LEUKAEMIA SUBSET BY FLOWCYTOMETRY IN T CELL ACUTE LYMPHOBLASTIC LEUKAEMIAS AND THEIR FOLLOW UP Seema Tyagi, Jasdeep Singh Department of Hematology, AIIMS, New Delhi, India Introduction and Background: T-cell acute lymphoblastic leukaemia (T-ALL) constitutes 15% of childhood cases and 25% of adult acute leukaemia cases. In 2009, a new subtype of T-ALL, early T-cell precursor ALL (ETP-ALL) was identified based on gene expression profiling and immunophenotyping. ETP-ALLs are associated with high risk of remission induction failure or early relapse with conventional therapies. We identified this subtype of T-ALL and looked for its response to therapy. Methods: In a prospective study 878 patients of suspected acute leukaemias, analysed by flowcytometry from 2014 to 2016. 48 patients of T-ALL were identified and followed up for a median of 6 months. Results: Of the 48 T-ALL patients, eight were detected as ETPALL, based on expression of myeloid, stem cell markers, absence of CD1a and CD8 and weak expression of CD5 by flowcytometry (prevalence 16.67%) . Response to steroids was similar in both ETP-ALL and T-ALL subsets, but response to induction therapy (66.7% vs 88.5%), overall survival and event free survival was significantly lower in ETP-ALL subset at six months of median follow up. Both disease and therapy related mortality was higher in the ETP-ALL subset (75% vs 7.4%). Conclusions: ETP-ALL is a high risk subset of T-ALL which can be identified by a comprehensive approach using morphology, cytochemistry and flowcytometry. We advocate
conditions that mimic the lymph node tumour microenvironment. Flow cytometry and western blotting were used to investigate effects on apoptosis induction, cell cycle progression, cell proliferation and intracellular signalling. MK2206 induced apoptosis in a dose dependent manner and was significantly more cytotoxic than idelalisib. We observed a greater-than-additive effect of binimetinib in combination with MK2206, suggestive of synergy. No synergy between binimetinib and idelalisib was observed. Interestingly, we observed an increase in AKT phosphorylation in response to binimetinib which was blocked by MK2206 but not idelalisib. Our data suggest that dual inhibition of MEK1/2 and AKT may be highly effective against CLL cells. The ineffectiveness of combining binimetinib with idelalisib suggests that the effects observed are independent of PI3-kinase d. Dual inhibition of MAPK-ERK1/2 and AKT signalling may be effective at targeting the proliferative/drug-resistant compartment of CLL that resides in the tumour microenvironment. ROUTINE BONE MARROW CYTOGENETICS IN INITIAL STAGING OF LYMPHOMA Charles J. Shuttleworth1, Robyn Lukeis2, Joanne E. Joseph1 1 Haematology Department, St Vincent’s Hospital, Sydney, and 2 Cytogenetics Department, St Vincent’s Hospital, Sydney, NSW, Australia Aim: To assess the utility of conventional cytogenetic analysis of bone marrow aspirates in initial staging of lymphoma. Method: Bone marrow aspirates performed during initial staging of lymphoma were reviewed at a single institution from 1/1/15 to 31/12/15. Fifty included a request for conventional cytogenetics. For each case, data was collected on: indication, final diagnosis, results of aspirate, trephine, flow cytometry and conventional cytogenetics, as well as whether diagnosis had been aided via other specimens. Results: Eight abnormalities were noted in seven of 50 cases (14%). Three of the abnormalities related to an age related loss of Y chromosome (non-pathogenic). One was a complex karyotype in a case with diffuse large B cell lymphoma. One was a hyperdiploid clone found in a case whose trephine displayed diffuse involvement with a T cell lymphoma. Two samples demonstrated a t(11;14) and were morphologically involved with mantle cell lymphoma (MCL). In both cases preceding lymph node biopsy had already established this diagnosis. None of these abnormalities changed the diagnoses or management in their respective cases. Discussion: A conventional karyotype appears to have a limited diagnostic and prognostic utility in the staging of lymphoma, and its routine ordering should be reviewed. SPONTANEOUS TUMOUR LYSIS SYNDROME AS AN UNUSUAL PRESENTATION OF B LYMPHOBLASTIC LEUKAEMIA/LYMPHOMA WITH PROMINENT HAEMOPHAGOCYTOSIS Fiona Swain, Louise Seymour, Bronwyn Williams Haematology Department, Pathology Queensland, Royal Brisbane and Women’s Hospital, Qld, Australia
S111
Background: Tumour lysis syndrome (TLS) is a serious complication of rapid cell death. It is mostly encountered following treatment of malignancies with high proliferative indices; however, spontaneous TLS has been described in haematological and non-haematological malignancies. We describe a case of paediatric B lymphoblastic leukaemia/lymphoma with spontaneous TLS and marked haemophagocytosis within the bone marrow. Case study: A 2-year-old girl presented with fever and irritability. Examination revealed splenomegaly. Initial investigations showed pancytopenia, multi-organ dysfunction and biochemical derangements consistent with TLS. Occasional blasts were seen on a blood film. A bone marrow aspirate and trephine was performed. There was a heterogenous population of lymphoblasts on the aspirate accounting for 19% of cells. Scattered histiocytes were evident. The trephine specimen was markedly hypocellular with a small infiltrate of blasts. Histiocytes accounted for most cells with prominent haemophagocytosis. Immunohistochemical profile of the blast population (interstitially and within histiocytes) was consistent with B lymphoblasts. Flow cytometry demonstrated an immunoprofile consistent with B lymphoblasts. Cytogenetic and molecular studies were unremarkable. Discussion: Classically, B lymphoblastic leukaemia/lymphoma demonstrates a hypercellular marrow with peripheral blood leucocytosis. In this unusual case, haemophagocytosis accounts for the hypocellularity of the marrow and would have contributed to the spontaneous TLS. DETECTION OF EARLY T CELL PRECURSOR LEUKAEMIA SUBSET BY FLOWCYTOMETRY IN T CELL ACUTE LYMPHOBLASTIC LEUKAEMIAS AND THEIR FOLLOW UP Seema Tyagi, Jasdeep Singh Department of Hematology, AIIMS, New Delhi, India Introduction and Background: T-cell acute lymphoblastic leukaemia (T-ALL) constitutes 15% of childhood cases and 25% of adult acute leukaemia cases. In 2009, a new subtype of T-ALL, early T-cell precursor ALL (ETP-ALL) was identified based on gene expression profiling and immunophenotyping. ETP-ALLs are associated with high risk of remission induction failure or early relapse with conventional therapies. We identified this subtype of T-ALL and looked for its response to therapy. Methods: In a prospective study 878 patients of suspected acute leukaemias, analysed by flowcytometry from 2014 to 2016. 48 patients of T-ALL were identified and followed up for a median of 6 months. Results: Of the 48 T-ALL patients, eight were detected as ETPALL, based on expression of myeloid, stem cell markers, absence of CD1a and CD8 and weak expression of CD5 by flowcytometry (prevalence 16.67%) . Response to steroids was similar in both ETP-ALL and T-ALL subsets, but response to induction therapy (66.7% vs 88.5%), overall survival and event free survival was significantly lower in ETP-ALL subset at six months of median follow up. Both disease and therapy related mortality was higher in the ETP-ALL subset (75% vs 7.4%). Conclusions: ETP-ALL is a high risk subset of T-ALL which can be identified by a comprehensive approach using morphology, cytochemistry and flowcytometry. We advocate