Circulating Cd34+ cell count differentiates primary myelofibrosis from other Philadelphia-negative myeloproliferative neoplasms: a pragmatic study.

A high number of circulating CD34+ cells has been advocated to distinguish primary myelofibrosis from other Philadelphia-negative myeloproliferative neoplasms. We re-evaluated the diagnostic interest of measuring circulating CD34+ cells in 26 healthy volunteers and 256 consecutive patients at diagnosis for whom a myeloproliferative neoplasm was suspected. The ROC curve analysis showed that a number of CD34+ <10/µl excludes the diagnosis of primary myelofibrosis with a sensitivity of 97 % and a specificity of 90 % (area under the curve: 0.93 [0.89-0.98]; p < 0.001). Patients with PMF harboring a CALR mutation had more circulating CD34+ cells than patients with either a JAK 2 or MPL mutation (p = 0.02 and p < 0.01, respectively). These results suggest that this fast, simple, non-invasive, and standardized test is of particular interest to exclude the diagnosis of primary myelofibrosis.

Plasma cell morphology in multiple myeloma and related disorders.

Normal and reactive plasma cells (PC) are easy to ascertain on human bone marrow films, due to their small mature-appearing nucleus and large cytoplasm, the latter usually deep blue after Giemsa staining. Cytoplasm is filled with long strands of rough endoplasmic reticulum and one large Golgi apparatus (paranuclear hof), demonstrating that PC are dedicated mainly to protein synthesis and excretion (immunoglobulin). Deregulation of the genome may induce clonal expansion of one PC that will lead to immunoglobulin overproduction and eventually to one among the so-called PC neoplasms. In multiple myeloma (MM), the number of PC is over 10% in most patients studied. Changes in the morphology of myeloma PC may be inconspicuous as compared to normal PC (30-50% patients). In other instances PC show one or several morphological changes. One is related to low amount of cytoplasm, defining lymphoplasmacytoid myeloma (10-15% patients). In other cases (40-50% patients), named immature myeloma cases, nuclear-cytoplasmic asynchrony is observed: presence of one nucleolus, finely dispersed chromatin and/or irregular nuclear contour contrast with a still large and blue (mature) cytoplasm. A peculiar morphological change, corresponding to the presence of very immature PC named plasmablasts, is observed in 10-15% cases. Several prognostic morphological classifications have been published, as mature myeloma is related to favorable outcome and immature myeloma, peculiarly plasmablastic myeloma, is related to dismal prognosis. However, such classifications are no longer included in current prognostic schemes. Changes related to the nucleus are very rare in monoclonal gammopathy of unknown significance (MGUS). In contrast, anomalies related to the cytoplasm of PC, including color (flaming cells), round inclusions (Mott cells, Russell bodies), Auer rod-like or crystalline inclusions, are reported in myeloma cases as well as in MGUS and at times in reactive disorders. They do not correspond to malignant changes of PC but are related to abnormal synthesis, trafficking, or excretion of the immunoglobulin that is stored in excess within the cytoplasm. Occurrence of crystalline inclusions within PC may be the first anomaly leading to the diagnosis of adult Fanconi syndrome. After a historical perspective, the authors report on the various morphological aspects of PC that may occur in multiple myeloma and related disorders, and discuss about their clinical and pathophysiological significance. Today, morphological identification and accurate determination of % PC within bone marrow remain ancillary criteria for the diagnosis of MM and help for the diagnosis of rare renal disorders.

[Peripheral blood Sézary cells and the diagnosis of Sézary syndrome]. / Recherche de cellules de Sézary dans le sang périphérique: morphologie ou immunophénotype?

Sézary syndrome (SS) is a rare and aggressive cutaneous lymphoma, and its diagnosis is based both on clinical, histological and biological features. None of these criteria taken alone is specific, and the two clinical observations reported here agree with this. Peripheral blood involvement, due to the presence of a variable number of Sézary cells, has been recently fully delineated by the ISCL/EORTC international organizations, and taken into account in the diagnosis and the prognosis of this syndrome. Identification and quantification of peripheral blood Sézary cells on the blood smear is an essential criterion for the diagnosis and is sufficient when associated with relevant clinical or/and histological grounds. Flow cytometry is another tool to demonstrate Sézary cells within the peripheral blood mononuclear cells. The authors discuss about the respective advantages and limits of morphology and flow cytometry in the identification and enumeration of circulating Sézary cells. Molecular biology is helpful in peculiar situations.

[Bone marrow necrosis in two patients with neoplastic disorders]. / Nécrose médullaire chez deux patients atteints de maladies cancéreuses.

Bone marrow necrosis is defined by extensive necrosis of the myeloid tissue and bone marrow stroma. Diagnosis is done on characteristic cytological pattern of the bone marrow aspiration and/or biopsy. We report two observations. The first patient, aged 75, has been hospitalized for fever, asthenia and lower back pain. An haematological malignancy was suspected after observation of a few peripheral blood blast cells, but necrosis was found on the bone marrow aspiration and could not lead to further haematological diagnosis. Within next days, the white blood cell count and the number of blasts increased, leading to the diagnosis of acute monoblastic leukaemia. A chemotherapy was started but the patient died 20 days after admission. The second patient, aged 28, has been hospitalized for severe bleeding a few days after the diagnosis of a metastatic gastric tumour. The bone marrow aspiration, made for the evaluation of a thrombocytopenia, showed a massive necrosis. The patient deceased shortly after hospitalization. According to literature, bone marrow necrosis is in most instances secondary to either an haematological malignancy (60%) or to a solid tumour (30%), but only at times observed with a non-malignant disorder. Bone pain, fever, cytopenias and elevated serum lactic dehydrogenase and alkaline phosphatase are frequently reported, but are mostly non specific of the diagnosis in these malignant conditions. Examination of the bone marrow leads to the diagnosis: cells are pycnotic, scarcely recognizable in a background of amorphous extracellular eosinophilic proteinaceous material, and histology shows disappearance of fat spaces with preservation of the bone tissue. Tissue hypoxemia due to microcirculation failure may be the main mechanism leading to the necrosis, whatever the related disorder. Supportive care together with specific therapy of the causal disease must be started promptly. The prognosis depends on the underlying illness and is generally very poor when extensive necrosis is observed.

The effect of nitric oxide donors on nitric oxide synthase-expressing myenteric neurones in culture.

Previously, we demonstrated that intestinal inflammation leads to a postinflammatory loss of nitric oxide synthase (NOS)-expressing myenteric neurones and motility disturbances. Here, we investigated whether high NO concentrations could be responsible for the decrease in NOS neurones. Myenteric neurone cultures, prepared from guinea-pig small intestine, were incubated with NO donors [sodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1)]. After fixation, NOS neurones were identified by NADPH diaphorase staining and neurone-specific enolase (NSE)-positive neuronal content was assessed with an enzyme-linked immunosorbent assay (ELISA)-based method. Twenty-four hours incubation with SIN-1 (10(-3) mol L(-1)) or SNP (10(-4) mol L(-1) or higher) reduced the number of NADPH diaphorase-positive neurones. SNP incubation did not affect the NSE-positive neuronal content. Shorter incubations (SNP: 4 and 12 h) had no significant effect. The SNP-induced reduction was reversed by glutathione (GSH), but not by NO- or O-scavengers, whereas GSH depletion enhanced the decrease. The NO-dependent guanylate cyclase-blocker 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) did not affect the SNP effect. This reduction can be explained by either specific apoptosis of NOS neurones or downregulation of NOS activity. However, TdT-mediated X-dUTP nick end labelling (TUNEL stainings argue in favour of the latter. In conclusion, the NO donor SNP decreases the number of NOS-expressing myenteric neurones time and concentration dependently, without affecting the amount of neuronal material. Glutathione plays an important protective role.

[Refractory anaemia with ringed sideroblasts (RARS) associated with marked thrombocytosis: a provisional entity in the WHO classification of haematological malignancies]. / Thrombocytose majeure et anémie réfractaire avec sidéroblastes en couronne: une entité provisoire dans la classification OMS des hémopathies.

The WHO classification describes a group of myelodysplastic/myeloproliferative diseases, including a provisional entity, refractory anaemia with ringed sideroblasts (RARS) associated with marked thrombocytosis, underlining that is a provisional entity without consensus of belonging to myelodysplastic rather than to myeloproliferative syndromes. The authors report two cases with features of refractory anaemia with excess of ringed sideroblasts and marked thrombocytosis. In the first case, RARS is concomitant with thrombocytosis and fits the WHO criteria for this temporary entity. The second case is a typical RARS, who developed a thrombocytosis after several years and emphasizes that a link, at least progressive, exists between RARS and myeloproliferative disorders. The authors summed up the various situations related to secondary or primary acquired sideroblastic anaemia, likewise to primitive and reactive thrombocytosis. The cases of RARS + marked thrombocytosis reported in the literature are few in number and do not allow to settle between a particular form of myelodysplastic syndrome and a myeloproliferative disorder, a fully justified reason to classify these patients in a temporary group. To date, there is no codified therapy for this disorders.

[Idiopathic hypereosinophilic syndrome: toward a new molecular-targeted therapy and a new cytomorphological and molecular definition]. / Hyperéosinophilie essentielle: nouvelle thérapeutique ciblée et nouvelle définition cytologique et moléculaire.

Idiopathic hypereosinophilic syndrome is characterised by chronic hypereosinophilia leading to tissue damage, and after exclusion of reactive eosinophilia. Until recently no specific or efficient therapeutic was available. In 2003, a recurrent interstitial deletion 4q12 leading to the fusion of the FIP1L1 and PDGFRA genes was detected in hypereosinophilic syndromes. The resulting protein has constitutive tyrosine kinase activity which explains clinical and cytological remission of hypereosinophilic syndrome after treatment by a specific tyrosine kinase inhibitor, imatinib mesylate or Glivec, usually used in chronic myeloid leukaemia. Here we report a patient with hypereosinophilic syndrome associated to peculiar morphology of neutrophilic series and the 4q12 deletion. He presented clinical and haematological remission since the introduction of imatinib mesylate therapy.

Is t(14;18)(q32;q21) a constant finding in follicular lymphoma? An interphase FISH study on 63 patients.

The translocation (14;18)(q32;q21) is the hallmark of follicular lymphoma (FL). However, conventional cytogenetics and PCR techniques fail to detect it in at least 10% of cases. In order to evaluate the true incidence of this translocation in FL, we analyzed 63 patients with FL, and 17 patients with diffuse large cell lymphoma (DLCL) corresponding to suspected FL transformations using interphase fluorescence in situ hybridization (FISH). Colocalized signals related to the translocation were observed in 19-92% of cells (median = 51%), corresponding to positivity over the threshold in all (63/63) cases. Similarly, 16/17 possibly secondary DLCL displayed the translocation. Although some cytogenetic changes might be missed by this FISH assay (such as rare insertion, or translocations with other chromosomal partners), our results stress t(14;18)(q32;q21) as an almost constant finding in FL. Our sensitive interphase FISH assay should be of great value to define FL more accurately, namely in patients included into therapeutic trials. Furthermore, this approach could be of interest in (re)defining some types of FL, especially the grade 3 FL which frequently lack t(14;18).

Is there any significance for intracellular crystals in plasma cells from patients with monoclonal gammopathies?

Several plasma cells morphological changes have been described in monoclonal gammopathies, including intracytoplasmic crystals. We report one case of indolent kappa-chain multiple myeloma with renal insufficiency, featuring plasma cells with Auer-rod-like intracytoplasmic inclusions. The relationship between such aberrations and those found in multiple-myeloma-associated adult Fanconi syndrome is discussed. The significance of intracellular storage and crystallisation of immunoglobulin within plasma cells remains partially unknown.

[Chronic lymphoid hemopathies in adults: chronic lymphocytic leukaemia and the phase of dissemination of small cell lymphomas]. / Les héopathies lymphoïdes chroniques de l'adulte: la leucémie lymphoïde chronique et le phase de dissémination des lymphomes à petites cellules.

Chronic lymphocytic leukaemia is the most frequent haematological cancer in adult patients, and its incidence raises with aging. Diagnosis needs several clinical and biological data, but hemogram together with the morphological and immunophenotypic analysis of the lymphoid cells take the major place. If the diagnosis is performed easily in about 65% of the patients, various clinicobiological entities were reported in the past few years that must be identified, at least because some are of adverse prognosis. Moreover, the other chronic lymphoid neoplasms, corresponding to the various low and intermediate grade non-Hodgkin's lymphomas (mainly of follicular type, marginal zone, mantle cell zone), may disseminate within the blood and the bone marrow. Those circulating lymphoma cells must be identified at diagnosis in order to perform the accurate diagnosis and to avoid an erroneous diagnosis of atypical chronic lymphocytic leukaemia. Up to 90% of lymphoid malignancies are B cell disorders, contrasting with only a few cases of T cell origin: some of those latter cases cannot be neglected however, as they may be observed in Western countries. Most recent classifications (REAL and WHO) defined all hematological malignancies: each entity referred to clinical, morphological, immunological, cytogenetic, and molecular findings. The basis of these classifications is pathophysiological, trying in each disorder to define a normal counterpart to the pathological clone. Reviewing main steps of the immune response in the normal patient, corresponding to those involving B cells, it is possible indeed to localize and demonstrate a function for many of the cells that expand in lymphoid malignancies.

Increased apoptosis in mononucleated cells but not in CD34+ cells in blastic forms of myelodysplastic syndromes.

INTRODUCTION: Myelodysplastic syndromes are characterized by peripheral refractory cytopenias together with normo or hyper cellular marrow. Increased apoptosis has been shown to be involved in the process leading to this paradox. MATERIALS AND METHODS: Early apoptosis detection, based on the modification of mitochondrial transmembrane potential (deltapsim), was performed on bone marrow cells from 42 MDS patients (21 RA, four RARS, 10 RAEB, two RAEB-t, three sAML, and two CMML) and seven normal healthy donors. Phosphatidylserine (PS) expression, a late/intermediate marker of the apoptotic cascade, was also quantified. Apoptosis was analysed by flow cytometry both on unsorted mononuclear cells and on progenitor cells after CD34+ magnetic cell sorting. RESULTS: A significant increase of apoptosis of MNC was observed in RA, RARS, RAEB and to a lower extent in RAEB-t and AML samples. In the progenitor compartment, RA and RARS samples presented a high level of apoptosis, whereas a switch to a low level of apoptosis was detected in the blastic forms RAEB, RAEB-t and sAML. Fas (CD95/APO-1), a member of the death domain receptor family, has been reported to be overexpressed on MDS CD34+ marrow cells. A functional assay of Fas cross-linking using the CH11 antibody on CD34+ marrow cells was performed on samples of 17 MDS patients; 8/17 were found to be sensitive to Fas-induced apoptosis. However, no correlation was observed with the level of in vivo spontaneous apoptosis. CONCLUSION: This study demonstrates increased apoptosis of MNC in all MDS subgroups as measured by deltapsim collapse. Moreover, while important apoptosis is still observed at the progenitor level in early MDS, blastic forms show a clear reduction of apoptosis. Study of Fas functionality modulates the implication of this receptor in the pathophysiology of the disease.

Chromosome 13 abnormalities identified by FISH analysis and serum beta2-microglobulin produce a powerful myeloma staging system for patients receiving high-dose therapy.

A careful prognostic evaluation of patients referred for high-dose therapy (HDT) is warranted to identify those who maximally benefit from HDT as well as those who clearly fail current HDT and are candidates for more innovative treatments. In a series of 110 patients with myeloma who received HDT as first-line therapy, times to event (disease progression and death) were studied through proportional hazard models, in relation to different prognostic factors, including a chromosome 13 fluorescence in situ hybridization (FISH) analysis using a D13S319 probe. Delta13 was detected in 42 patients (38%). Follow-up time among surviving patients and survival time were 48 +/- 3 and 51 +/- 7 months, respectively (median +/- SE). In the univariate analysis, Delta13 was the most powerful adverse prognostic factor for all times to event, especially for the survival time (P <.0001) and was followed by beta2-microglobulin (beta2m) levels 2.5 mg/L or higher (P =.0001). The comparison of survival prognostic models including beta2m 2.5 mg/L or greater and another factor favored the Delta13/beta2m combination. In 22 patients (20%) with no unfavorable factor, the median survival time was not reached at 111 months. In contrast, among 55 patients (50%) with one unfavorable factor and 33 patients (30%) with 2 unfavorable factors, median survival times were 47.3 +/- 4.6 months and 25.3 +/- 3.2 months, respectively (P <.0001). We conclude that delta13, adequately detected by FISH analysis, is a very strong factor related to poor survival, especially when associated with a beta2m level of 2.5 mg/L or higher. Routine FISH Delta13 assessment is strongly recommended for patients considered for HDT.

Comparison of four serum-free, cytokine-free media for analysis of endogenous erythroid colony growth in polycythemia vera and essential thrombocythemia.

INTRODUCTION: The assay of endogenous erythroid colony formation (EEC), a characteristic of polycythemia vera and essential thrombocythemia, is not standardized. In this multicentric study, we tested four semisolid, serum-free, cytokine-free media based on either methylcellulose (M1, M2) or collagen (C1, C2) commercialized for the EEC assay. MATERIALS AND METHODS: Bone marrow mononuclear cells (BMMC) from 73 individuals (62 patients with either polycythemia vera (26), essential thrombocythemia (19), secondary polyglobuly (17) or chronic myeloid leukemia (2) and 11 healthy donors) were grown in parallel in the four media without, or with 0.01 U/ml erythropoietin (EPo). RESULTS: In all four media EEC formation was specific, as it was not observed in cultures of patients with secondary polyglobuly or chronic myeloid leukemia, nor of healthy donors. Analysis of fresh or MGG-stained collagen gel cultures allowed detection of EEC formation significantly more frequently than methylcellulose-based media; addition of 0.01 U/ml of EPo had little or no effect on EEC formation. Collagen-based medium C1 gave better results than the other media tested: the 'C1' EEC assay was positive for 68.2% of polycythemia vera cultures with significantly higher median EEC numbers (6.5/10(5) BMMC for patients with one major criteria of polycythemia vera and 19 and 21/10(5) BMMC for patients with two or three major criteria, respectively). Medium C1 was also better for essential thrombocythemia cultures with 47.4% of positive results but with a low median EEC number (6.7/10(5) BMMC). When associated with the ELISA dosage of serum EPo, the 'C1' EEC assay allowed confirmation or elimination of the diagnosis of polycythemia vera for 91% (20/22) of polyglobulic patients. CONCLUSION: We propose that serum-free collagen-based culture systems be considered to standardize the EEC assay, now part of the new criteria of polycythemia vera.

[Acquired von Willebrand disease and lymphoproliferative syndromes]. / Maladie de Willebrand acquise et syndromes lymphoprolifératifs.

OBJECTIVE: Acquired von Willebrand disease occurs in patients with or without cutaneous and mucosal bleeding who have no personal or family history of the disease. The clinical course of these patients is poorly known due to the rarity of acquired von Willebrand factor (vWF) deficit. We conducted this study to assess the clinical course of acquired vWF deficit secondary to lymphoproliferative syndromes. PATIENTS AND METHODS: We report the clinical course of acquired von Willebrand disease in 6 patients with monoclonal gammapathy of undetermined significance, multiple myeloma, chronic lymphoid leukemia, Wadenstöm's macroglobulinemia, or lymphoma who were followed for 1 to 11 years. RESULTS: Acquired von Willebrand disease was suspected in non-thrombocytopenic patients with a lymphoproliferative syndrome who developed a hemorrhagic syndrome. The vWF anomaly was symptomatic in 4 of 6 patients at diagnosis. Patients were given symptomatic treatment with vWF replacement therapy as needed and specific treatment for their lymphoproliferative syndrome. Administration of DDAVP was sufficient in 3 out of 4 patients to allow invasive procedures but was unable to control digestive ulcer bleeding that required infusion of factor VIII-vWF concentrate. For 2 patients, chemotherapy was initiated due to threatening massive hemorrhage. The result was spectacular. The 4 other patients have been asymptomatic without treatment for 3, 5, 6 and 11 years during which time their lymphoproliferative syndrome has been quiescent. CONCLUSION: The clinical features and laboratory findings are similar in patients with congenital or acquired von Willebrand disease, but specific and etiologic chemotherapy is indicated for patients with acquired disease.

Use of pathology-specific peripheral blood CD34 thresholds to predict leukapheresis CD34 content with optimal accuracy: a bicentric analysis of 299 leukaphereses.

CD34+ cell counts in peripheral blood (PB) and corresponding numbers of CD34+ cells and colony-forming units-granulocyte/macrophage (CFU-GM) in 299 leukapheresis products of 209 patients undergoing PB progenitor cell (PBPC) mobilization for autologous transplantation in two different centers were analyzed and compared according to diagnosis: non-Hodgkin lymphoma (NHL, 94 leukaphereses), multiple myeloma (MM, 75), Hodgkin's disease (HD, 37), solid tumors (35), and chronic myeloid leukemia (CML, 32). Without separating disease entities, correlations between PB CD34+ cell counts and leukapheresis content of CD34+ cells (r>0.83, P<0.01) and CFU-GM (r>0.81, P<0.01) were excellent. In both centers, a PB CD34 threshold ensuring a leukapheresis yield > 10(6) CD34/kg was determined. This threshold was higher in center 1 than in center 2, and its predictive accuracy (91.4%, i.e., prediction correct 91.4% of the time) was significantly lower than in center 2 (98.4%, P=0.02). When data were analyzed by pathology, PB CD34+ cell counts and leukapheresis content of CD34+ cells and CFU-GM remained well correlated, and in both centers PB CD34 thresholds predictive of a yield > 10(6) CD34/kg per leukapheresis could be determined for each pathology. For most patients, pathology-specific PB CD34 thresholds could be obtained directly from the equation of the PB CD34/leukapheresis CD34 correlation curve; they varied depending on both pathology and center (range: 7-20 x 10(6) CD34/l). Pathology-specific thresholds predicted a leukapheresis yield > or = 10(6) CD34/kg accurately 100% of the time for MM patients in center 2 and HD and solid tumor patients of both centers, resulting in overall rates of accurate prediction of sufficient graft CD34 content of 96.6% in center 1 and 98.9% in center 2.

[Monoclonal gammopathies of undetermined significance]. / Les gammapathies monoclonales de signification indéterminée.

INTRODUCTION: Monoclonal gammopathy of undetermined significance is an asymptomatic disorder associated with serum monoclonal immunoglobulin spike. Its incidence is about 1% in patients of 50 years of age, and rapidly increases in elderly patients. CURRENT KNOWLEDGE AND KEY POINTS: Within the 20 years following diagnosis, about 25% of patients will evolve towards either multiple myeloma (for patients with IgG or IgA) or malignant lymphoproliferative disorder (for patients with IgM). Definition, circumstances associated with a transient monoclonal spike, and currently available parameters used for differential diagnosis with either multiple myeloma or malignant lymphoproliferative disorder are successively discussed. One part of the most usual biological parameters is of prognostic value, and is reviewed in more detail. Recent data concerning immunophenotype, cytogenetics and molecular biology of plasma cells reinforce the link between the asymptomatic condition and multiple myeloma. In monoclonal gammopathy of undetermined significance, some plasma cells resemble normal or reactive plasma cells, whereas others mimic those found in multiple myeloma. FUTURE PROSPECTS AND PROJECTS: The most recent biological data are also discussed in order to evaluate whether some would help to discriminate those patients who will remain asymptomatic lifelong from those who will evolve towards multiple myeloma.

Mature plasma cells as indicator of better prognosis in multiple myeloma. New methodology for the assessment of plasma cell morphology.

The relationship between plasmablastic cells and outcome in multiple myeloma (MM) has been established for nearly 15 years. But the assessment of these cells is not easy to perform and it allows the identification of only a small proportion of patients. We investigated the plasma cell morphology using a progressive evaluation of consecutive criteria: nucleolus, chromatin and nuclear-cellular ratio (N/C). The combination of these three items produces a subclassification where four cellular subtypes identify 93% of the plasma cells, and these subtypes are related to the outcome. The interest of this methodology is to be based on the mature plasma cells that are easier to identify than the plasmablastic cells. These new cell subtypes introduce a new classification for patients: Group 1 includes patients with at least 66% mature plasma cells (P000). Both Group 2 and 3 have less than 66% P000 and are separated by their degree of maturation (Proplasma I > or = Proplasma II + plasmablastic). The distinction of these three groups of patients is highly related to the prognosis (P < 10(-4)). These results have been confirmed on a second group of patients coming from a different institution. In conclusion, we propose a new methodology for the plasma cell evaluation in MM, that is based on the morphological criteria and that has the advantage of identifying an intermediate (30%) subgroup of patients with a prognostic significance.

Transient leukemoid disorder in a newborn with Down syndrome followed 19 months later by an acute myeloid leukemia: demonstration of the same structural change in both instances with clonal evolution.

A transient leukemoid disorder (TLD) was observed in a newborn with Down syndrome (DS), demonstrating a clonal abnormality: 47,XX,der(X;15)(p10;q10),+21(c). Spontaneous remission was observed, but 19 months later an acute leukemia from the myeloid series was discovered. Cytogenetic study revealed the same structural change as at birth, with karyotypic evolution corresponding to addition of one chromosome 8 and a fourth chromosome 21. These findings demonstrate, at least in our patient, that TLD and the subsequent acute leukemia are closely related and that TLD, closely related to DS, must be viewed as a preleukemic disorder undergoing spontaneous remission. A review of literature data shows that most cytogenetic studies reported so far are related to either TLD or acute leukemia in DS. Serial studies performed in the same patient are quite infrequent and, to the best of our knowledge, there is only one other report demonstrating a cytogenetic relation between TLD and the subsequent acute leukemia.