[Allogenic bone marrow transplantation in multiple myeloma. Analysis of 12 consecutive cases]

BACKGROUND

Allogeneic bone marrow transplantation (BMT) is the only potentially curative treatment in multiple myeloma (MM).

METHODS

From january 1986 to december 1993, 12 cases (10 males and 2 females) underwent BMT in the authors' institution. The mean age of the series was 39 years (range 23-49). The situation of the myeloma on initiation of the conditioning was: complete remission (CR) in 2 cases, objective response in 5 cases, partial response in 1 case and treatment resistance in 4 cases. The conditioning schedule included cyclophosphamide (120 mg/kg) and total body irradiation (10-14 Gy) with or without melfalan at high doses in 11 patients and busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 1 case. The prophylaxis of graft versus host disease (GVHD) was carried out with methotrexate and cyclosporine A (CsA) in 7 cases, CsA plus prednisone in 2 cases and 3 patients received CsA plus bone marrow partially depleted of T lymphocytes by elutriation.

RESULTS

The situation of the myeloma with regard to response following transplantation was: unevaluable in 1 case, resistant in 1 case, objective response in 2 cases and CR in 8 cases. Seven out of the 10 patients at risk presented grades II-IV GVHD. Four of the 8 patients who were in CR following transplantation died due to post transplant complications and 2 out of the 6 relapsed 9 months after the transplant while 2 remain in CR at 5 and 8 years after the transplant, respectively. Nine patients died due to infection in 2 cases, GVHD and infection in 4 cases, GVHD and hemorrhage in 1 case and progression and infection in 2 cases. Of the 3 surviving patients, 1 relapsed at 14 months after the transplant and two remain in CR at 5 and 8 years post transplantation.

CONCLUSIONS

Bone marrow transplantation conditioning gives place to a high number of complete remission in multiple myeloma. However, the incidence of acute grade II-IV graft versus host disease and mortality due to complications related to the transplantation are very high. Nonetheless, a proportion of patients may achieve curation with bone marrow transplantation.

Analysis of the clinical relevance of the breakpoint location within M-BCR and the type of chimeric mRNA in chronic myelogenous leukemia

It has been suggested that the breakpoint location within the M-BCR segment of chromosome 22 and the type of chimeric mRNA BCR/ABL (b2a2 or b3a2) are associated with differences in the clinical and hematological characteristics of chronic myelogenous leukemia (CML). To assist in clarifying this matter, in a series of Ph-positive CML patients the relationship of both the breakpoint location within M-BCR (n = 71) and the type of chimeric mRNA BCR/ABL (n = 40) with the chronic phase duration, patients' survival, and thrombopoietic activity was analyzed. Median survival for patients with breakpoints in zones 1+2+3 (n = 38) and zones 4+5 (n = 31) was 62 and 75 months, respectively, the difference being not significant; patients with breaks in zones 1+2 (n = 19) and zones 3+4+5 (n = 50) had a median survival of 50 and 67 months, respectively (P also not significant). Moreover, no significant differences were found in the survival of patients with b2a2 (n = 16) and b3a2 (n = 24) mRNA junctions. Finally, no differences were observed in the platelet or megakaryocyte counts between patients with breakpoints in extremes 5' and 3' nor between patients with b2a2 and b3a2 mRNA. The above results are in agreement with those reported in most recent studies, confirming the lack of clinical relevance of molecular pattern in CML.

[Bone marrow transplantation from unrelated donors in chronic myeloid leukemia: the results in 15 patients]

BACKGROUND

Bone marrow transplantation (BMT) from a histocompatible donor is the only curative treatment in chronic myeloid leukemia (CML). Only a minority of patients dispose of an adequate donor from among his/her relatives. The remaining transplant receptors must look to unrelated donors (URD). The experience of the Escuela de Hematología Farreras Valentí (Farreras Valentí School of Hematology, Barcelona, Spain) in BMT from URD in CML in the first chronic phase is herein reported.

METHODS

Fifteen patients (9 males and 6 females, median age 33 years; range 14-48 years) were transplanted from October 1988 to May 1994. Serologic identity was expressed in the A, B and D loci in 9 cases and minor incompatibility in 6. Conditioning included total body irradiation and cyclophosphamide in 14 patients and busulphan plus cyclophosphamide in 1. Partial and selective T lymphocyte depletion was performed by elutriation in 7 cases.

RESULTS

Primary implant failure was detected in 2 out of 14 risk patients (14%) and secondary failure was observed in 3 out of 12 cases (25%). The actuarial probability of acute graft versus host disease (GVHD) was 55 +/- 15% at 7 weeks with a probability of appearance with an intensity of II-IV of 31 +/- 13%. Five out of 7 patients with a survival of greater than 100 days, developed chronic GVHD (71%). Ten presented fatal complications. In 5 cases, death was due to pulmonary problems. Recurrence of CML was not observed in any of the patients in the series. The probability of disease free survival at 2 years was 30 +/- 12%.

CONCLUSIONS

Bone marrow transplantation from an unrelated donor is an effective treatment for a proportion of patients with chronic myeloid leukemia although severe complications are frequent and originate a high mortality.

P53 tumor suppressor gene in chronic myelogenous leukemia: a sequential study

Loss of the p53 gene alleles was investigated in 26 patients with Ph+, BCR/ABL+ chronic myeloid leukemia (CML) by means of the polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis using the restriction enzyme AccII. In all cases, peripheral blood and/or bone marrow samples were obtained at different times during the chronic phase of the disease and at blast crisis, and in some of them also at the accelerated phase. Of the 12 cases considered informative, 11 evolved into myeloid type blast crisis and one into a lymphoid blast crisis, whereas only two showed an i(17q) chromosome at cytogenetic study. In four of the 12 informative cases, a loss of one p53 gene allele was observed, in all cases coincident with the development of the accelerated phase or blast crisis. One patient with a deleted p53 gene allele, in whom it was possible to analyze the gene structure in the three CML evolutive phases (chronic and accelerated phases and blast crisis), showed loss of the p53 gene allele in both the accelerated and the blastic phase, but not during the chronic phase. On the other hand, one of the two cases with an i(17q) chromosome exhibited one allelic deletion of the p53 gene. Thus, the relatively frequent monoallelic deletion of the p53 gene coincident with the appearance of the blast crisis registered in the present study would support a possible role of the p53 gene alterations in the evolution of CML to its final stages.

[Intravenous amphotericin B as prevention of deep mycoses in allogeneic bone marrow transplantation]

BACKGROUND

To evaluate the efficacy of i.v. amphotericin B (AmB) as prophylaxis of deep mycosis (DM) in allogenic bone marrow transplantation (BMT).

METHODS

From July 1991 to May 1993, 45 consecutive patients treated by allogenic BMT with no previous history of systemic mycosis and with normal renal function were administered prophylactic AmB at a dose of 0.5 mg/kg/48 h from day + 1 BMT until hemoperipheral recovery (group A). These were compared with an historic control group made up of 45 consecutive patients submitted to BMT from January 1990 to June 1991 who did not receive prophylactic AmB (group B). During the neutropenic phase all the patients remained in isolation units with laminar flow of filtered air and were administered oral non absorbable antibiotic therapy and diet of low bacterial content. The incidence of DM and the dose of AmB administered during the first 120 days post BMT were evaluated.

RESULTS

In the first 30 days following BMT 3 (7%) cases of DM were observed in group A and 3 (7%) in group B. Four (9%) additional cases were found from days 30 to 120 in group A and 3 (7%) in group B. In 3 (7%) patients of the group which received prophylaxis and in 4 (9%) of the control group Candida spp. was isolated. In 3 (7%) patients from group A and 1 (2%) patient from group B the infection was due to Aspergillus. Although the patients from group A received therapeutic AmB less frequently (78% vs 91%) and later (13 [SD +/- 5.9] vs 9.2 [SD +/- 4.6] days) than those of group B (p < 0.002) the mean dose of AmB per patient treated was similar in both groups (11.3 [SD +/- 8.8] vs 11.8 [SD +/- 7] mg/kg).

CONCLUSIONS

The prophylactic use of systemic amphotericin during the neutropenic phase of bone marrow transplantation does not reduce either the incidence of deep mycosis or the mean dose of amphotericin administered.

[Pulmonary cavitation as the initial manifestation of Hodgkin's disease]

Most of the patients with Hodgkin's disease (HD), have lymph nodes in the anterior mediastinum. Nonetheless, it is exceptional for one of these adenopathies to be cavitated at diagnosis. The case of a patient with HD presenting a cavitated anterior mediastinal mass as one of the initial symptoms. The differential diagnosis of localized masses in the anterior mediastinum and cavitated images in conventional thoracic radiology is discussed.

Different response to recombinant human granulocyte-macrophage colony-stimulating factor in primary and secondary graft failure after bone marrow transplantation

The efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) in graft failure after bone marrow transplantation (BMT) has been evaluated in 25 patients. rhGM-CSF was administered intravenously at a dose of 5 or 10 micrograms/kg. Fourteen patients (seven allogeneic BMT [allo-BMT], seven autologous BMT [ABMT]) were treated for primary bone marrow failure (no granulocyte recovery after BMT), and 11 cases (all allo-BMT) received rhGM-CSF for secondary bone marrow failure (absolute neutrophil count lower than 0.5 x 10(9)/L after a previously sustained granulocyte recovery). Two allo-BMT and three ABMT patients with primary bone marrow failure achieved a granulocyte response to rhGM-CSF. In contrast, nine patients with primary graft failure did not respond to rhGM-CSF (four ABMT, three HLA-identical T-depleted BMT, one minor mismatch BMT, one unrelated BMT). Ten of 11 allo-BMT patients treated for secondary bone marrow failure attained an ANC higher than 0.5 x 10(9)/L, but most became severely neutropenic again at a median time of 4 weeks. The possible cause triggering graft failure (graft-vs.-host disease [GVHD], cytomegalovirus [CMV] infection) remained unsolved in most of these cases. Actuarial probability of survival of the entire series was 16 +/- 9% at 15 months. The severity of graft failure and the presence of other concomitant complications in most of our patients may justify these poor results. In conclusion, rhGM-CSF had less efficacy in patients with primary bone marrow failure than in those with secondary bone marrow failure. In the latter setting, measures addressed to correct the initial cause of graft failure are mandatory.

[Immunophenotyping study of bone marrow fractions obtained by elutriation in allogeneic bone marrow transplantation]

PURPOSE

Bone marrow transplantation (BMT) is an effective treatment for acute and chronic leukaemias. Lymphocyte depletion of donor bone marrow for preventing GVHD has been associated with a higher incidence of relapse after allogeneic BMT. This association suggests an antileukaemic effect of donor lymphocytes. In vitro studies show that cytotoxic T lymphocytes (CD3+ CD56+) and NK cells (CD3-CD56+) have an antileukaemic effect. To know which specific subpopulation of lymphocytes are depleted by counterflow centrifugation or elutriation, we analysed B, T, NK cells and hematopoietic precursors in the marrow fractions after this procedure.

PATIENTS AND METHODS

Eight patients (6 CML, 1 ALL, 1 B-CLL) received an allogeneic BMT with lymphocyte depletion of the bone marrow graft using elutriation. After a Percoll gradient, donor marrow mononuclear cells (MNC) were separated with this method in five fractions (F1 to F5).

RESULTS

Lymphocyte depletion of donor marrow was in average of 1.7 log. This depletion was also selective, the last fraction containing higher number of cytotoxic T lymphocytes and NK cells than the other fractions. Recovery of CD34+ cells in the four fractions concerning to post-Percoll marrow was 84%, most of them being in the last fraction.

CONCLUSIONS

The use of elutriation for lymphocyte depletion is a good method for graft manipulation with the feasibility to adjust a lymphocyte/Kg. dose. Elutriation may be effective in reducing the incidence and severity of graft versus host disease and preserving the antileukaemic effect.

Immunophenotypic characteristics of blast crisis of chronic myeloid leukaemia: correlations with clinico-biological features and survival

Blast cells from 40 patients with Philadelphia-positive chronic myeloid leukaemia (CML) in blast crisis were analysed by immunophenotypic methods. In 27 cases, BCR gene studies were also performed. By light microscopy morphology and cytochemistry the cases were classified as follows: undifferentiated (n = 7; 17.5%), myeloid (n = 27; 67.5%), and lymphoid (n = 6; 15%). On the basis of the immunological markers, the cases were reclassified as: myeloid (n = 17; 42.5%), megakaryoblastic (n = 17; 42.5%), and lymphoid (n = 6; 15%). The seven cases initially considered as undifferentiated by morphological and conventional cytochemical criteria were classified as myeloid (four cases) and megakaryoblastic (three cases) by marker analysis. The monoclonal antibody anti-myeloperoxidase (anti-MPO) was the most sensitive myeloid associated marker in these cases, being positive in five of them. A significant proportion (27%) of non-lymphoid blast crisis cases were CD7-positive, and myeloid markers were positive in the four lymphoid CML-CB cases studied. Analysis of the clinico-haematological characteristics on the various subgroups of patients showed that patients with lymphoid blast crisis had shorter duration of the chronic phase, more frequent extramedullary blastic involvement, more favourable response to therapy, and longer survival. Finally, a trend for an association between megakaryoblastic involvement of blast crisis and breakpoint localization in the 3' extreme of the M-bcr segment was also noted.

Ph-positive chronic myeloid leukemia mimicking essential thrombocythemia and terminating into megakaryoblastic blast crisis: report of two cases with molecular studies

Two patients with chronic myeloid leukemia (CML) presenting with the hematologic features of essential thrombocythemia (ET) are reported. At diagnosis they showed extremely high platelet counts (4985 and 2800 x 10(9)/l, respectively) and moderate leukocytosis (21 and 17 x 10(9)/l, respectively). In both cases, in addition to the Philadelphia chromosome (Ph), a rearrangement within the major breakpoint cluster region on chromosome 22 was demonstrated, with the breakpoint in the 3' extreme. In patient 1 the disease initially responded to radioactive phosphorus and hydroxyurea, but during the evolutive course a progressive increase in the white blood cell counts was noted, reaching values typical of the chronic phase of CML, and the patient eventually died from blast crisis 45 months after diagnosis. In patient 2, although good control of the platelet counts was achieved with hydroxyurea, the disease also evolved into a blast crisis four months after diagnosis. In both cases monoclonal antibodies and electron microscopy studies demonstrated the megakaryocytic nature of the blast cells. The above features are not consistent with the present and similar cases being Ph-positive ET. Instead, they should be regarded as a special form of CML characterized by a marked protagonism of the megakaryocytic component.

Prognosis of chronic myeloid leukemia: studies from the Barcelona Group

Individual and multicenter efforts have facilitated the recognition of different parameters with prognostic value at presentation of chronic myeloid leukemia (CML). Interest is currently focused on the prognostic evaluation of features obtained from molecular analysis, and isolation of data with evolutive predictive value. The site of breakpoint within the M-BCR has been suggested as a prognostic factor in some studies. A recent analysis from our group failed to demonstrate differences in either duration of chronic phase or survival between patients with 5' and 3' breakpoints. We have confirmed in a sequential study that a decrease in the expression of some myeloid differentiation antigens of the blood granulocytes can be a prognostic indicator along CML evolution. Our more recent study, separating blast crises on immunological and molecular grounds, confirms lymphoid cases as a distinct subgroup and shows a trend for an association between megakaryoblastic blast crisis and 3' location of the breakpoint.

Sequential study of myeloid differentiation antigens of neutrophil granulocytes in different phases of chronic myeloid leukaemia: natural history and prognostic significance

In an attempt to contribute to the knowledge of the natural history of Philadelphia-chromosome-positive chronic myeloid leukaemia (CML) and its prognosis, we analyzed sequentially the myeloid differentiation antigens of peripheral blood neutrophil granulocytes (NG) in different evolutive stages of the disease. Four monoclonal antibodies (CD15, CD24, 31D8, and 13F6) were used, and a total number of 116 sequential studies were performed in 43 patients. At diagnosis, there is a significant decrease of NG expressing myeloid differentiation antigens, which recover to nearly normal levels after initial control of the disease. The onset reduction is probably due to the circulation of incompletely mature NG. In accelerated/blastic phase NG expressing myeloid differentiation antigens decrease again, probably due to a true antigen loss. This reduction could herald by a few months the development of accelerated/blastic phase. In such a case, its predictive strength is higher than that of the well recognized initial prognostic parameters in CML. These results indicate that the sequential study of NG myeloid differentiation antigens may contribute to both a better understanding of the natural history of CML and the evolutive prognosis of this disease.

[Systemic chronic candidiasis following typhlitis caused by Candida albicans]

Typhlitis is an infrequent infectious complication which may appear during a period of intense granulocytopenia, generally in patients with acute leukemia. The most common causal germs are Gram negative bacilli although the importance of Candida sp. as an etiologic agent of this disease is ever more frequent. The case of a 14 years old patient with acute lymphoblastic leukemia who, after chemotherapy treatment, presented typhlitis by Candida albicans followed by chronic systemic candidiasis (CSC) is described. The role that Candida albicans may play in some cases of typhlitis is discussed as is the relation between the appearance of typhlitis and the posterior development of CSC.

Mitoxantrone and intermediate-dose cytosine arabinoside for poor-risk acute leukemias: response to treatment and factors influencing outcome

Mitoxantrone (MIT, 12 mg/m2, i.v. 5 days) and intermediate-dose cytosine arabinoside (IDAC 1 g/m2/12 h, i.v. 3 days) was given to 43 patients with poor-risk acute leukemias (AL). Moderate or severe toxicity was infrequent. The proportion of complete remissions (CR) in the main patient categories was as follows: 15/18 (85 per cent) in acute myeloid leukemia (AML) in the first relapse, 2/6 in ALL in the first relapse, 0/2 in AML in relapse after bone marrow transplantation (BMT), 2/7 in AML refractory to first-line treatment (REF-AL), and 1/6 in postmyelodysplastic (PMD-AL) plus secondary AL (S-AL). The mortality rate during induction was 23 per cent. Median duration of CR was 24 weeks. The multivariate prognostic factor analysis on CR obtention showed that data concerning treatment for the first relapse and platelet count higher than the median of the series were favourable. On the contrary, PMD-AL, S-AL and REF-AL were unfavourable situations. A percentage of marrow erythroblasts superior to the median was a favourable prognostic factor for survival. Finally, the duration of CR after MIT-IDAC was directly related to the duration of previous CR. In conclusion, MIT-IDAC was highly effective to attain CR in AML in the first relapse. However, due to the poor long-term results in these patients, additional measures are recommended after CR.

[Molecular analysis of chronic Philadelphia chromosome negative myeloid leukemia: study of 6 cases]

BACKGROUND

Patients with Philadelphia negative (Ph-) chronic myeloid leukemia (CML) constitute a small proportion of the total number of patients with CML. Molecular analysis of these cases has permitted recognition that some cases present a breakpoint in the bcr region of chromosome 22, that is, the alteration constituting the substrate of the Ph chromosome. To date, the number of patients analyzed to this regard is low.

METHODS

Six patients with Ph negative CML who constituted part of a series of 96 patients diagnosed with CML over a period of 6 years were studied. Analysis of the BCR gene in the DNA of the leuko-concentrate of peripheral blood was carried out with the Southern Blot technique, using the 3' and 5' probes and Transprobe and the restriction enzymes Bgl II, Eco RI, Hind III and Bam HI. The principal clinical-hematological characteristics of the patients were analyzed.

RESULTS

Breakpoints were observed in the bcr region of chromosome 22 in 3 of the 6 patients, all of whom presented typical CML clinical-hematological features.

CONCLUSIONS

Half of the patients with Philadelphia negative (Ph-) chronic myeloid leukemia (CML) have a breakpoint in the bcr region of chromosome 22, a similar molecular pattern to the Ph positive CML and their clinical-hematological profile is indistinguishable from those with CML.

Specific cutaneous lesions in a CD8+ peripheral T-cell lymphoma

Histopathologic, immunohistochemical, and ultrastructural studies were carried out on cutaneous lesions of a 43-year-old man with an aggressive peripheral T-cell lymphoma involving the lung, central nervous system, bone marrow, and skin. Some results are distinctive and not previously reported, such as extremely strong epidermotropism, aberrant CD8+ immunophenotype with lack of one pan T antigen (CD5), and giant cytoplasmic granules. We discuss these features comparing them with other hematologic malignancies usually involving the skin, such as cutaneous T-cell lymphoma, adult T-cell leukemia/lymphoma, angiocentric lymphomas, and malignant histiocytosis.

The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.

Low frequency of ras oncogene mutations in Philadelphia-positive acute leukemia and report of a novel mutation H61 Leu in a single case

Activating ras mutations are frequent (25-60%) in chronic myelomonocytic leukemia (CMML) and in acute myeloid leukemia (AML) (30%), in contrast to chronic myeloid leukemia (CML) in which the incidence is very low (0-3%). This might reflect that the leukemic cell in CML is at a level of differentiation in which ras gene activation is not involved or, alternatively, might be due to the presence in CML of the bcrlabl fused gene. We have analyzed the presence of point mutations in codons 12, 13, 59, 61 and 63 of N-, K-, and H-ras genes, in 26 cases of Philadelphia-chromosome-positive, bcrlabl-positive acute leukemia (Ph+ AL), and in eight CMML cases by using the polymerase chain reaction. Aberrant ras genes were detected in a single Ph+ AL case, and in four out of eight CMML patients. The Ph+ AL showing altered ras allele had an unusual point mutation in H-ras gene, substituting leucine for glutamine. This mutation has not been previously found in any hematological disease. Our findings suggest that ras mutations are probably not involved in the pathogenesis of those leukemias in which blast cells contain bcrlabl oncogene activation.

[Molecular genetics in the diagnosis of acute leukemia and chronic lymphoproliferative syndromes in 121 cases]

BACKGROUND

The introduction of biology and molecular genetics in the hematological laboratory has brought about a new and spectacular advance in the study of cloning and cytological characterization of malignant hemopathies. The principal aim of the present study was to analyze the contribution of this new technology in the diagnosis of acute leukemia (AL) and chronic lymphoproliferative syndromes (CLS) through analysis of lymphoid clonality and genetic rearrangement proper to the lymphoid differentiation of the B and T cells.

METHODS

The genetic rearrangement of the heavy chain immunoglobulins (IgH) and the beta (beta) and gamma (gamma) chains of the T receptor (TRC) in 121 patients with the following malignant hemopathies: acute myeloid leukemia (AML), 28 cases; acute lymphoblastic leukemia (ALL), 27 cases; and CLS, 66 cases. The Southern method was used.

RESULTS

Clonality analysis: presence of genetic rearrangement (clonality) in all the cases of lymphoblastic AL (ALL) and CLS and in 5 of 28 cases of AML (3 IgH and 2 TRC). Strain analysis: presence of absolute coincidence (exclusive rearrangement of the IgH or TRC genes in proliferations of the B or T strain, respectively) in 18 of 27 cases (67%) of ALL, in 14 of 15 cases (93%) of T-CLS and in all cases (100%) of B-CLS.

CONCLUSIONS

In malignant hemopathies the analysis of genetic rearrangement constitutes a method of great practical use for determining the presence of lymphoid clonality and is a good complement to conventional morphological and immunophenotypic procedures for cytological characterization of the same.

alpha Interferon in chronic lymphocytic leukaemia

The role of alpha interferon in patients with chronic lymphocytic leukaemia (CLL) has yet to be well established. In studies carried out to date, a significantly higher response rate has been observed in previously untreated patients compared to those who have received prior chemotherapy. Patients with early-stage CLL also respond better than patients with advanced disease. Responses to alpha interferon are transient and complete responses are rare. It is not yet known whether alpha interferon can induce clonal remission, and response is usually measured in terms of the reduction in peripheral blood lymphocyte levels. In one study, a normalization of immunoglobulin levels was observed, and in another there was an increase in the absolute number of granulocytes. Further studies are needed to investigate the role of combined therapy with alpha interferon and cytotoxic agents or other cytokines, and to assess the ability of alpha interferon to prolong response duration after remission induction with chemotherapy. Toxicity is tolerable when alpha interferon is given in a low dose (e.g., 2 million units (MU)/m2 three times a week) and low doses have been shown to be as effective as high doses in CLL patients.

Treatment of early stage-B chronic lymphocytic leukemia with alpha-2b interferon after chlorambucil reduction of the tumoral mass

Eleven patients with early CLL (two in Rai's stage 0, seven in stage I, and two in stage II) received aIFN (3 MU subcutaneously three times a week for a median of 8 months; range, 4-12) after their tumor mass had been reduced with intermittent chlorambucil. Following chlorambucil/aIFN administration, a significant reduction in blood lymphocyte counts (from 25.1 +/- 12.0 x 10(9)/l to 6.3 +/- 5.32 x 10(9)/l; p less than 0.001) and in CD 19-positive cells (from 21.0 +/- 12.0 x 10(9)/l to 3.8 +/- 2.3 x 10(9)/l; p less than 0.001) was observed. Three of seven patients with stage-I and one of two with stage-II disease moved to stage 0, and a complete response (CR) was observed in two patients with stage-I at diagnosis. Overall, there were eight patients who, after treatment, had either a CR (2 cases) or stage-0 disease (6 cases), which compares favorably with two patients with stage-0 disease before entering the study (p = 0.015). In five patients (including the two who achieved a CR) aIFN further improved the disease status achieved with chlorambucil.

Multiple K-ras codon 12 mutations in cholangiocarcinomas demonstrated with a sensitive polymerase chain reaction technique

By using a modified polymerase chain reaction strategy, we have devised an approach to detect a K-ras oncogene mutated at codon 12 in the presence of 1000 normal alleles. This is a considerable improvement in sensitivity on previous assays. Application of this assay to 15 cholangiocarcinomas showed that all contained a K-ras mutation to codon 12 and that nine of the tumors contained two or more mutations. In 11 cases, mutations were present in less than 10% of the cells in the sample. In common with pancreatic adenocarcinomas, in which 75 to 95% of cases contain a mutation in K-ras, cholangiocarcinomas show a very high frequency of ras gene mutation, but within a tumor only a fraction of cells contain a ras mutation. The presence of multiple mutations and the low frequency of mutant alleles in the samples argue against K-ras mutations being the initiating genetic lesion in this tumor, but suggest that ras gene mutation is involved in the stepwise progression of neoplastic cells to full malignancy.