Acute lymphoblastic leukemia with giant intracytoplasmic inclusions

Malformation of the endoplasmic reticulum system evolving into giant inclusions and Auer bodies in acute promyelocytic leukemia: an ultrastructural study of 6 cases

The endoplasmic reticulum（ER）is the largest membranous network serving as a region for protein, lipid and steroid synthesis, transport and storage. Detailed information about ER-cisternae, ER-tubules and rough endoplasmic reticulum (rER) is scarce in human blood cells. This study describes a series of giant inclusions and Auer bodies in promyeloblasts in six patients with acute promyelocytic leukemia (APL), by light microscopy, transmission electron microscopy (TEM) and cytochemical stains. TEM revealed that giant inclusions and pro-Auer bodies were associated with rER and surrounded by tubular structures composed of degenerated or redundant membrane in promyeloblasts, which corresponded with elements of the ER system. This paper reveals that in the promyeloblasts of APL, ER is the source of and transforms progressively into giant inclusions and Auer bodies.

Development of Auer bodies from giant inclusions associated with rough endoplasmic reticulum in acute promyelocytic leukemia

Giant inclusions and Auer bodies in promyeloblasts were investigated in a study which included transmission electron microscopy (TEM) for morphology and ultrastructural cytochemistry for myeloperoxidase in 10 patients with acute promyelocytic leukemia (APL). Ultrastructural cytochemistry demonstrated positive myeloperoxidase reactivity in giant inclusions, expanded rER cisternae, Auer bodies and primary granules. TEM revealed that giant inclusions were adorned by degenerated rER membrane, some of them sharing features with Auer bodies. We hypothesize a novel origin for Auer body development in promyeloblasts of APL, namely that they originate from peroxidase-positive and expanded rER cisternae, and that primary granules were directly released from these expanded rER elements, bypassing the Golgi apparatus.

Granular acute lymphoblastic leukemia: a case report and literature review

Authors report a rare case of granular acute lymphoblastic leukemia (ALL) in a 45-year-old woman with a history of multiple myeloma. The patient's lymphoblasts contained large numbers of distinctive cytoplasmic granules closely mimicking heavily granulated myeloblasts in acute myeloid leukemia. These blasts were completely negative for myeloperoxidase but positive for acid phosphatase and Periodic Acid-Schiff reaction by cytochemical staining. Immunophenotype analysis by immunohistochemistry clearly demonstrated precursor B-cell phenotype. Granular ALL occurs approximately 2 to 7% in childhood populations but is extremely rare in adults. Such cases may cause problematic distinction from myeloid differentiation and lead to misdiagnosis of acute myeloid leukemia. Ten cases of adult granular acute lymphoblastic leukemia described to date in the literature were also reviewed.

Granular acute lymphoblastic leukemia in adults: report of a case and review of the literature

The diagnosis of granular acute lymphoblastic leukemia (ALL) can be problematic as the cytoplasmic granules found in many blast cells may mimic those seen in acute myelogenous leukemia (AML). This rare variant of B-cell ALL is more commonly diagnosed in children, but may occur in adults. We report a case of granular B-ALL in a 56-year-old female and review the literature.

Megamitochondria formation - physiology and pathology

Mitochondria undergo structural changes simultaneously with their functional changes in both physiological and pathological conditions. These structural changes of mitochondria are classified into two categories: simple swelling and the formation of megamitochondria (MG). Data have been accumulated to indicate that free radicals play a crucial role in the mechanism of the MG formation induced by various experimental conditions which are apparently various. These include ethanol-, chloramphenicol- and hydrazine-induced MG formation. Involvement of free radicals in the mechanism of MG formation is showed by the fact that MG formation is successfully suppressed by free radical scavengers such as alpha-tocopherol, coenzyme Q(10), and 4-OH-TEMPO. Detailed mechanisms and pathophysiological meanings of MG formation still remain to be investigated. However, a body of evidence strongly suggests that enormous changes in physicochemical and biochemical properties of the mitochondrial membranes during MG formation take place and these changes are favorable for membrane fusion. A recent report showed that continous exposure of cells with MG to free radicals induces apoptosis, finding which suggests that MG formation is an adaptative process to unfavorable environments at the level of intracellular organelles. Mitochondria try to decrease intracellular reactive oxygen species (ROS) levels by decreasing the consume of oxygen via MG formation. If mitochondria succeed to suppress intracellular ROS levels, MG return to normal both structurally and functionally, and they restore the ability to actively synthesize ATP. If cells are additionally exposed to excess amounts of free radicals, MG become swollen, membrane potential of mitochondria (DeltaPsim) decreases, cytochrome c is released from mitochondria, leading to activation of caspases and apoptosis is induced.

Granular acute lymphoblastic leukemia in a 15-year-old boy

We report a case of a boy with acute lymphoblastic leukemia expressing granular inclusions in the cytoplasm of blastic cells. Granular lymphoblasts had mostly L2 morphology but azurophilic granules were also present in part of the cells with L3 morphology. Immunophenotyping clearly indicated a lymphoid origin of the blasts and showed positivity of HLA-DR, CD10, CD19 and CD24 markers. Cytogenetic analysis brought normal karyotype 46 XY. Molecular genetic analysis showed immunoglobulin heavy chain rearrangement (IgH R/R) and T-cell receptor gamma rearrangement pattern (TCR-gamma C/R). TCR-beta and TCR-delta did not show rearrangements. The course of the disease was favourable. The patient achieved initial complete remission within 4 weeks of protocolar treatment and the remission remains until now, 5 years from the diagnosis and three years after finishing the treatment.

Auer rod-like inclusions in adult common acute lymphoblastic leukemia

We report a case of adult common acute lymphoblastic leukemia, defined by enzyme histochemistry and immunophenotypic analysis, which had rod-shaped cytoplasmic inclusions that on Wright's-stained peripheral blood smear resembled Auer rods. Electron microscopic analysis of a buffy coat preparation revealed that the inclusions were not characteristic of Auer rods, but rather that they were composed of concentric lamellar structures with no limiting membrane and were closely associated with the nuclear membrane. Therefore, the presence of Auer rod-like inclusions in blasts on a Wright's-stained peripheral blood smear does not preclude a diagnosis of acute lymphoblastic leukemia.

Hypergranular acute lymphoblastic leukemia (ALL). Report of a case and review of the literature

We report a case of adult acute lymphoblastic leukemia (ALL) with myeloid-like hypergranulation of blast cells. Like most of the "granular" ALLs described in the literature, the blast cells had L2 morphology and exhibited a common-ALL immunologic phenotype. The clinical findings at diagnosis were unremarkable. Cytogenetic analysis showed a 46XY karyotype. Molecular genetic analysis revealed T-cell receptor (TCR) gamma and immunoglobulin heavy chain rearrangements; no rearrangement was found at the TCR beta gene locus. The polymerase chain reaction (PCR) for the BCR-ABL translocation was negative. The clinical course of the patient was uncomplicated. On standard ALL treatment protocol he achieved complete remission (CR) within 4 weeks, and he is currently disease free 8 months after diagnosis. The case contributes well-documented data to the characterization of adult "granular" ALL, with special regard to changes at the molecular genetic level.

Biological and clinical features of acute lymphoblastic leukaemia with cytoplasmic granules or inclusions: description of eight cases

We describe eight patients (four children and four adults) with an acute lymphoblastic leukaemia (ALL) with cytoplasmic granules or inclusions. The incidence of this variant of acute leukaemia in our whole series of patients with ALL is 1.8%. The granules or inclusions were usually positive for aspecific esterases (ANAE) and/or acid phosphatase, and the immunophenotype was in all cases typical of a CALLA positive B-lineage ALL (CD10+, CD19+ and/or CD24+, DR+, TdT+, anti-T-, anti-My-, SIg-). In one paediatric case, CD33 was unusually coexpressed. Ultrastructural investigations were performed in one case and demonstrated large granules containing vesicles, usually membrane bound, in the majority of blast cells. In the two cases analysed, Ig heavy chain gene rearrangement was detected. In this series of patients prognosis was poor since three never achieved a complete remission, four relapsed and only one is still in first continuous remission.

Granular common acute lymphoblastic leukaemia in adults: a morphological study

2 cases of acute lymphoblastic leukaemia characterised by the presence of cytoplasmic inclusions morphologically similar to azurophil granules are described. Azurophil granulation of blasts is one of the cardinal features which differentiate acute myeloid from acute lymphoblastic leukaemia. Although such granulation of lymphoblasts has caused diagnostic confusion in the past, we found that the granules could be distinguished from myeloid azurophil granules both morphologically and by their characteristic cytochemical staining reactions. They were negative for peroxidase/sudan black and chloroacetate esterase, but gave coarse scattered granular positivity for both acid phosphatase and alpha-naphthyl acetate esterase. Both the electron microscopic appearance of the granules and their cytochemical staining reactions suggested that they were lysosomes. Granular ALL does not appear to be associated with any morphological subtype or karyotype; but is strongly associated with the common ALL phenotype. Its prognostic significance remains uncertain. It occurs more frequently than the small number of previous reports might suggest and, given the potential for misdiagnosis, should be more widely recognised.

Granular acute lymphoblastic leukaemia of childhood: a morphological phenomenon

Three hundred and twenty consecutive children with lymphoblastic leukaemia (ALL), treated on the Medical Research Council UKALL VIII schedule, had their Romanowsky stained diagnostic marrows reviewed for the presence of azurophil granules in blast cell cytoplasm. Twenty patients (7%) had greater than 5% blasts showing this feature; 19 had the cell phenotype of "common ALL." Male children and those with French-American-British (FAB) L2 morphology predominantly showed this feature. There was also a strong correlation between granularity and non-diffuse acid phosphate positivity, but no obvious difference between the 20 patients in their response to treatment emerged during a minimum follow up of 15 months. The "granular" variant occurs in around 7% of children with ALL, but has no clear prognostic importance. Morphologists should be aware of its existence and incidence to avoid confusion with acute myeloid leukaemia.

Cytoplasmic inclusions and virus-like particles in blast cells in acute lymphoblastic leukemia

Cytoplasmic inclusions and virus-like particles are described in blast cells of peripheral blood from a 16-year-old female with acute lymphoblastic leukemia. Three kinds of inclusions were identified on electron microscopy. The first type of inclusion was single membrane-bounded vacuoles, some of which contained virus-like particles, the second was lysosome-like structures, and the third appeared to be of mitochondrial origin. Virus-like particles were round in shape and had a diameter of 26 to 58 nm. They consisted of an electron-dense outer membrane and an electron-lucent core. At the present time the exact nature and significance of these virus-like particles still remain unclear.

Two types of intracytoplasmic inclusions in the cells of a patient with acute lymphoblastic leukemia

A patient with acute lymphoblastic leukemia (ALL) with cells containing two types of cytoplasmic inclusions is described. The inclusions appeared as globular bodies containing electron dense material with homogeneous structure and as crystalloid formations confined in organelles with structure similar to that of the surrounding mitochondria. In distinction to other reports, these structures were not related to the endoplasmic reticulum. The possibility that some of them represented altered mitochondria is discussed.

Acute lymphoblastic leukemia in children: current status, controversies, and future perspective

Disease-free survival (DFS) in childhood ALL is 60%, and survival in good, average, and poor prognostic groups defined by initial WBC and age is 90, 60, and 45%, respectively. Additional immunological, morphological, biochemical, cytokinetic, and cytogenetic factors have been identified, illustrating the heterogeneity of ALL and its derivation from malignant clones at various stages of differentiation and with varying rates of proliferation. Of biologic importance, these factors may refine further the characteristic features of clinically-determined prognostic groups. Multivariate analysis of large prospective trials with homogeneous therapy will be required to determine the independent prognostic importance of these factors. Current treatment strategies in ALL include (1) tailoring therapy and its intensity to prognostic groups; (2) multiple-drug combinations in induction; (3) early use of intrathecal (IT) methotrexate (MTX); (4) CNS prophylaxis with IT MTX alone in good prognosis patients and combined cranial radiation (CXRT), 1800 rads plus IT MTX, in average and poor prognosis patients. Current studies show a CNS relapse rate of 5% in all prognostic groups. Late neuropsychological defects caused by cranial XRT and IT MTX have prompted programs designed to reduce the potential late toxicity of CNS prophylaxis. More pronounced in younger children, these abnormalities include decreased IQ, visual-motor incoordination, poor performance in mathematics, and memory dysfunction. Until 1980, more intensive induction, consolidation, and maintenance therapy had failed to prolong DFS in children with a poor prognosis. In West Germany (Berlin-Frankfurt-Muenster protocol) a 70 to 75% DFS is seen in all patients regardless of initial WBC, suggesting that effective therapy will override prognostic factors. Ultra-high-dose MTX, without cranial radiation, is also showing promise in poor prognosis patients. Other issues include the optimal duration of therapy, the role of testicular biopsies, and prophylactic testicular radiation. Recent studies suggest that prognostic factors lose their significance after 2 years of continuous complete remission and that 2 years of maintenance therapy is adequate. Bilateral open-wedge testicular biopsies have identified occult testicular disease in 8 to 10% of males. A unified approach to children with leukemia/lymphoma, a group with a particularly poor prognosis, utilizing NHL-type therapy may be more effective than conventional ALL therapy.(ABSTRACT TRUNCATED AT 400 WORDS)