Stefan Schwartz

Successful treatment of cerebral aspergillosis with a novel triazole (voriconazole) in a patient with acute leukaemia

Invasive aspergillosis is an increasing problem in patients with acute leukaemia, bone marrow transplantation, immunosuppression after solid organ transplantation, or acquired immunodeficiency syndrome. Despite available antifungal treatment, the mortality approaches 100% in patients with dissemination of the infection into the central nervous system (CNS). Using a novel triazole, voriconazole, we successfully treated an Aspergillus brain abscess in a patient with acute leukaemia. Drug levels above the minimal fungicidal concentration for Aspergillus species were detected in cerebrospinal fluid (CSF) specimens, and the treatment achieved an objective response.

Prognostic significance of additional chromosome abnormalities in adult patients with Philadelphia chromosome positive acute lymphoblastic leukaemia

The clinical and biological significance of additional chromosome aberrations was investigated in a large series of 66 adult patients with Philadelphia (Ph) chromosome positive acute lymphoblastic leukaemia (ALL). Additional chromosome changes were observed in 71% of the cases. 9p abnormalities were identified in 26%, and monosomy 7 as well as hyperdiploid karyotypes >50 were both found in 17% of cases. 9p anomalies were characterized by a low complete remission (CR) rate (58%) and an extremely short median remission duration (MRD; 100 d). In patients with monosomy 7, the poor treatment outcome was confirmed (CR rate 55%; MRD 113 d). In contrast, all patients with hyperdiploid karyotypes >50 achieved CR, and the overall survival was superior to all other Ph‐positive ALL patients except those without additional chromosome aberrations. Exclusive rearrangement of the minor breakpoint cluster region of the BCR gene and lack of coexpression of myeloid‐associated antigens in cases with 9p anomalies as well as a high frequency of rearrangements of the major breakpoint cluster region of the BCR gene in patients with monosomy 7 (89%) further substantiated that additional chromosome aberrations may characterize distinct subgroups of Ph‐positive ALL. Moreover, the necessity of the complementing use of chromosome banding analyses, polymerase chain reaction (PCR) assays, and fluorescence in situ hybridizations in the accurate identification of Ph‐positive patients has become evident due to variant Ph translocations in 3%, and negative PCR assays in 4% of the cases.

Expression of the C-Kit Receptor (CD117) is a Feature of Almost All Subtypes of De Novo Acute Myeloblastic Leukemia (AML), Including Cytogenetically Good-Risk AML, and Lacks Prognostic Significance

Because of conflicting reports on the prognosis of patients with c-kit receptor positive AML and lacking correlations with cytogenetic analyses, we prospectively evaluated the c-kit receptor expression in 917 AML patients (750 adult patients; 167 children) using flow cytometry and compared the results to the immunophenotype, morphological and cytogenetic findings as well as clinical outcome. Expression of the c-kit receptor was present in 63% of all AML investigated. Among these an immature immunophenotype was more frequent and 30% had a CD34+/CD15- and 37% a CD34+/CD14- phenotype, whereas only 9% and 10% showed these phenotypes in the c-kit receptor negative group, respectively. C-kit receptor expression ranged average in M0 and M1 subtypes (69% versus 70%) but was less pronounced among M5 subtypes (21%). Results of karyotyping were available in 280 patients. C-kit receptor expression occurred in 37 of 42 (88%) patients with favorable cytogenetic abnormalities such as t(8;21), t(15;17) or inv(16) which exceeded the expression rate in patients with intermediate risk, poor risk or other abnormalities. Information about the clinical outcome was available in 228 patients treated according to the protocols of two German multicenter trials (AML-BFM, AMLCG). We found no difference of CR-rate or event-free survival (EFS) in adults with or without c-kit receptor expression. Children with c-kit receptor negative AML had a lower CR-rate and EFS, but also a lower median age and a higher frequency of M5 subtype as compared to children with c-kit receptor expression. In conclusion, analysis of c-kit receptor expression may help to identify phenotypically immature AML but fails to identify myeloid differentiation of leukemic blasts in approximately one third of patients. We found no evidence of an adverse prognosis in AML patients with c-kit receptor expression. Analysis for c-kit receptor expression does not appear to add information to established prognostic parameters in AML.

Detection by monoclonal antibodies of the Wilms' tumor (WT1) nuclear protein in patients with acute leukemia

The WT1 gene encodes a transcriptional regulator which during embryogenesis is involved in growth control and differentiation of diverse tissues. It is also expressed in few human malignancies, including acute leukemia. We tested 3 different monoclonal antibodies (MAbs H2, H7, HC17) and the polyvalent serum WTC‐19 for WT1 protein detection in mononuclear cell (MNC) preparations of 104 newly diagnosed acute leukemia patients. Using RT‐PCR, these MNC preparations were also analyzed for WT1 gene expression. MAbs H2, H7 and HC17 and the polyclonal WTC‐19 exhibited nuclear immunoreactivity in 63 of 99, 28 of 56, 38 of 60 and 22 of 43 WT1 gene‐expressing leukemia samples, respectively. With these antibodies, no WT1 immunoreactivity was found in MNCs from blood of healthy volunteers, from CD34+progenitor cell‐enriched leukapheresis products of patients conditioned for peripheral stem cell harvest or from reactive bone marrow. Contrary to WTC‐19, all MAbs reacted highly specifically with the WT1 protein (0.71 vs. 1.0). The WT1 protein was heterogeneously detected in leukemia blast preparations by all antibodies, irrespective of cell morphology. Very few HL60 cells and blasts from newly diagnosed leukemia patients interspersed among normal blood MNCs (50 blasts among 5 × 105MNCs) were easy to identify by indirect immunofluorescence using MAbs H2 and HC17. Taken together, MAbs H2 and HC17 were superior to MAb H7 and the polyvalent WTC‐19 in detecting the WT1 nuclear protein. Int. J. Cancer 70:518–523.

Poor efficacy of amphotericin B-based therapy in CNS aspergillosis

Recently, improved response and survival rates in patients treated with voriconazole and neurosurgery for central nervous system (CNS) aspergillosis have been reported. We assessed retrospectively the outcome in 17 patients with definite or probable CNS aspergillosis treated with amphotericin B alone (n = 15) or in combination with 5‐fluorocytosine (n = 3) or itraconazole (n = 2). Four patients underwent neurosurgery. The mortality rate was 100% with a median survival of only 10 days (range: 3–60) after onset of first symptoms or first radiological evidence of CNS aspergillosis. In conclusion, treatment with amphotericin B and itraconazole has negligible efficacy in CNS aspergillosis.

Clinical presentation of invasive aspergillosis

Summary. Invasive aspergillosis has increasingly been recognised to cause significant morbidity and mortality in immunocompromised patients. Fever unresponsive to broad‐spectrum antibiotics is the earliest and most common sign of an invasive fungal infection. As invasive Aspergillus infections are usually acquired by inhalation of Aspergillus conidia, symptoms of a pulmonary infection such as cough, rales and marked pleuritic chest pain can be noted early in the course, whereas hemoptysis typically comes late after neutrophil recovery. Aspergillus infections of the upper respiratory tract may also involve the nasal cavity or sinuses resulting in nasal obstruction, epistaxis, facial pain, periorbital swelling and even palate destruction. Primary cutaneous infections present as non‐purulent ulcerations and may be seen in association with implantable intravenous devices. Other sites of infections, such as the central nervous system, originate from dissemination of molds and may be suspected when focal neurological findings or meningism develop. The recognition of symptoms associated with invasive aspergillosis in patients at risk should prompt further diagnostic procedures, as an early diagnosis and immediate institution of antifungal therapy might improve the treatment outcome in this life‐threatening condition.

Possible regulation of Wilms' tumour gene 1 (WT1) expression by the paired box genes PAX2 and PAX8 and by the haematopoietic transcription factor GATA-1 in human acute myeloid leukaemias

Summary. Overexpression of the embryonic transcription factor, Wilms’ tumour protein 1 (WT1), is common in acute myeloid leukaemias (AML). Mutations of Wilms’ tumour gene 1 (WT1) in AML are rare and WT1 expression may be increased by other transcription factors. PAX2, PAX8 and GATA‐1 are known physiological regulators of WT1. In the present study, we analysed either bone marrow or blood samples of 43 AML patients for the expression levels of WT1, PAX2, PAX8 and GATA‐1 by real‐time reverse transcription polymerase chain reaction (LightCycler). Bone marrow samples of patients without haematological malignancies and stem cell preparation samples from healthy donors and lymphoma patients served as controls. PAX2 expression was found in 11 of 43 AML samples, with a clear correlation of PAX2 with WT1 expression levels observed. PAX8 expression was found in two additional samples. GATA‐1 expression was detectable in 41 of 43 AML samples and also in all control samples; no significant differences between these groups were observed and no correlation of GATA‐1 expression with WT1 expression levels was apparent. In conclusion, PAX2, and possibly PAX8, appears to be a candidate for the upregulation of WT1 in a proportion of AML, whereas GATA‐1 expression cannot be explained as an inducer of WT1. In two‐thirds of leukaemias from our series, the basis of WT1 upregulation cannot be explained by the simple upregulation of the known WT1 activators.

Morphological and cytochemical findings in 150 cases of T‐lineage acute lymphoblastic leukaemia in adults

We evaluated the morphological findings in 150 consecutive cases of T‐lineage acute lymphocytic leukaemia (T‐ALL). Cytochemistry including PAS staining and acid phosphatase reaction proved of limited value for the diagnosis of ALL.

Common clonal T‐cell origin in a patient with T‐prolymphocytic leukaemia and associated cutaneous T‐cell lymphomas

Summary. An unusual course was observed in a patient with indolent T‐prolymphocytic leukaemia (T‐PLL) who subsequently developed mycosis fungoides (Mf), lymphomatoid papulosis (LyP) and cutaneous CD30+ anaplastic large cell lymphoma (ALCL). Polymerase chain reaction analysis demonstrated identical monoclonal T‐cell receptor‐β and ‐γ gene rearrangements in all the different clinical entities. Furthermore, cytogenetic studies revealed the same aberrant clone with trisomy of chromosome 8 in T‐PLL and ALCL cells. This unique observation suggests that in T‐PLL, the leukaemic cells might undergo secondary transformation, subsequently resulting in different phenotypes of cutaneous T‐cell lymphoma.

Intramedullary abscess in a patient with disseminated Scedosporium apiospermum infection

A 35-year-old man was admitted with a relapsed acute lymphoblastic leukaemia (ALL). The initial diagnosis had been made 4 years earlier and at that time a proven invasive pulmonary aspergillosis had been successfully treated with voriconazole. Following initial chemotherapy, the patient entered complete remission. Following relapse, re-induction chemotherapy was given. During this chemotherapy, disseminated bluish-red cutaneous lesions developed over the entire trunk and head, despite oral itraconazole prophylaxis. The lesions initially had a clear vesicle, but subsequently developed central necrosis (top). A skin biopsy showed filamentous fungal elements (bottom left). Despite amphotericin B, liposomal amphotericin B, allogeneic granulocyte transfusions and, finally, voriconazole therapy, the fungal infection progressed with a microbiologically confirmed intraocular mycosis, orbital cellulitis and an intramedullary abscess (bottom right, arrow). Microbiological testing ultimately detected Scedosporium apiospermum. Despite sensitivity to voriconazole (and resistance to itraconazole, fluconazole, flucytosine and amphotericin B), confirmed by in vitro testing, and recovery from neutropenia, the patient developed multiple brain abscesses and died of progressive fungal infection. Scedosporium is a rare filamentous fungus subdivided into two species: S. prolificans and S. apiospermum. Because of its broad resistance to antifungal agents, infections in immunocompromised patients are often fatal.