Biomedical subjects

M Santoro

Publications and source records attributed to M Santoro.

At least 109 records · Page 6Linked to original sources

PubMed1998

Identification and characterization of a novel RING-finger gene (RNF4) mapping at 4p16.3.

We have isolated a new human RING-finger gene (RNF4) that encodes a 190-amino-acid protein. RNF4, in addition to the carboxyl-terminally located RING-finger motif, contains two putative nuclear localization signals and stretches of acidic amino acids that are similar to the activation domains of some transcription factors. RNF4 was expressed at low levels in all human tissues examined, with the notable exception of very high expression in the testis. The mouse homolog of RNF4 was abundantly expressed in embryonic tissues from the earliest days postgestation and exhibited a ubiquitous pattern of expression as assessed by in situ hybridization. We have mapped RNF4 to 4p16.3, a chromosome region associated with several genetic and neoplastic diseases. RNF4 spans 47 kb, is composed of eight exons, and maps immediately proximal to the anonymous locus D4S183, between the huntingtin (HD) and the fibroblast growth factor receptor 3 (FGFR3) genes.

Amino Acid Sequence↗

PubMed1998

Ion trap mass spectrometry for the characterization of N-methyl-1- (3,4-methylene-dioxyphenyl)-2-butanamine and N-ethyl-3,4- methylenedioxyamphetamine, two widely distributed street drugs.

The potential of ion trap mass spectrometry has been evaluated for the characterization and distinction of two isomeric amphetamines drugs, namely N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and N-ethyl-3,4-methylenedioxyamphetamine. Whereas the electron impact spectra of the two molecules lack specificity, collisional experiments on the ionic species at m/z 72 allows unequivocal distinction between the two isomers. Analogous results are achieved by positive ion chemical ionization and collisional experiments on the protonated molecules. All the different approaches have been successfully applied to the gas chromatography/mass spectrometry analysis of a tablet of illicit drug.

3,4-Methylenedioxyamphetamine↗

PubMed1998

Molecular biology of the MEN2 gene.

Cancer is a genetic disease caused by 'gain of function' mutations of oncogenes and 'loss of function' mutations of tumour suppressors and of genes involved in DNA repair mechanisms. The RET gene encodes a tyrosine kinase receptor for molecules belonging to the glial cell line-derived neurotrophic factor (GDNF) family. RET is a paradigmatic example of how different mutations of a single gene can lead to different neoplastic phenotypes. Indeed, gene rearrangements, often caused by chromosomal inversions, activate the oncogenic potential of RET in a fraction of human thyroid papillary carcinomas. On the other hand, different point mutations activate RET in familial multiple endocrine neoplasia syndromes familial medullary thyroid carcinoma (FMTC), MEN-2A and MEN-2B. Little information is so far available on the biochemical mechanisms by which the potent transforming and mitogenic signals of RET are delivered to the nucleus. However, recent data indicate coupling to the Shc-Ras-MAPK pathway as a necessary step in RET signal transduction.

Carcinoma, Papillary↗

PubMed1998

Avascular osteonecrosis in patients treated for Hodgkin's disease.

The aim of this study is to assess the risk of avascular osteonecrosis (AVN) of the femoral head in patients treated for Hodgkin's disease (HD), in relation to the type of treatment they have received. For this purpose, a cohort of 1391 patients treated for HD at University of Rome between 1972 and 1996 was divided into 2 groups according to their initial treatment. The first group contained 784 patients treated, at the onset of HD, either with chemotherapy (CT) containing steroids, combined in some cases with subdiaphragmatic radiotherapy (RT), or with subdiaphragmatic RT combined with CT without steroids. The second group was made up of 607 patients who had received, initially, supradiaphragmatic RT alone or supradiaphragmatic RT combined with CT without steroids. For the purpose of this study, only the 784 patients belonging to the first group were observed for the appearance of AVN, which occurred in 9 cases. The period of time which elapsed between the end of treatment and the radiological evidence of AVN ranged from 23 to 97 months, with an average of 35 months. Because the number of cases of AVN was so small, the pathogenesis of this complication could not be identified.

Adolescent↗

PubMed1998

Primary non-Hodgkin's lymphoma of the liver: case report.

This paper describes a rare occurrence of primary lymphoma of the liver in a young female and demonstrates the possibility of making the correct diagnosis by ultrasonically guided fine needle aspiration biopsy. A 32-year old female suffering from upper abdominal pain, hepatomegaly, nausea, anorexia and weight loss for almost 2 months was admitted to our Department. After a clinical and instrumental (lab exams, ultrasonography, computed tomography) evaluation, we reached the correct diagnosis of hepatic primary non-Hodgkin's lymphoma by means of ultrasonically guided fine needle aspiration biopsy. Two weeks after hospitalization the patient was treated with 8 cycles of CHOP chemotherapy and then with alpha-2b interferon immunotherapy. The hepatic ultrasonography and CT abdominal scan showed the complete absence of the lymphomatous lesions 36 months later. Up to February 1998, the patient was well and led a normal life. We conclude that the CHOP chemotherapy plus interferon immunotherapy were effective and well tolerated with a complete response 38 months following diagnosis.

Adult↗

PubMed1998

Glial cell line-derived neurotrophic factor differentially stimulates ret mutants associated with the multiple endocrine neoplasia type 2 syndromes and Hirschsprung's disease.

Ret is a receptor tyrosine kinase involved in several neoplastic and developmental diseases affecting the thyroid gland and tissues of neuroectodermal origin. Different ret mutations are associated with different disease phenotypes. Gain-of-function of ret is caused by gene rearrangements in thyroid papillary carcinomas and by point mutations in multiple endocrine neoplasia (MEN) type 2A syndrome (MEN2A), in familial medullary thyroid carcinoma (FMTC), and in the more severe MEN2B syndrome. Conversely, Hirschsprung's disease (HSCR) is associated with loss of function of ret. Recently, it has been shown that glial cell line-derived neurotrophic factor (GDNF), by binding to the accessory molecule GDNFR-alpha, acts as a functional ligand of Ret and stimulates its tyrosine kinase and biological activity. To ascertain whether the biological effects of ret mutations are modulated by GDNF, we have investigated the responsiveness to GDNF of ret mutants in cell lines coexpressing GDNFR-alpha and MEN2A-, MEN2B-, FMTC-, or HSCR-associated ret mutants. Here, we show that triggering of GDNF affected only ret/MEN2B, i.e. it stimulated ret/MEN2B mitogenic and kinase activities, as well as its ability to phosphorylate Shc, a bona fide Ret substrate. In contrast, ret mutants associated with MEN2A or FMTC (carrying Cys634 or Cys620 mutations) were unresponsive to GDNF. HSCR mutations, by affecting either the extracellular or the intracellular Ret domain, impaired responsiveness to GDNF. These data suggest that the phenotype of human diseases caused by ret mutations can be differentially influenced by GDNF.

3T3 Cells↗

PubMed1998

The ret/ptc1 oncogene is activated in familial adenomatous polyposis-associated thyroid papillary carcinomas.

Familial adenomatous polyposis (FAP) is caused by germ-line mutations of the apc gene, and it is associated with an increased risk of developing papillary thyroid carcinomas. We have previously reported that a significant fraction of sporadic human papillary thyroid carcinomas is characterized by gene rearrangements affecting the ret protooncogene. These rearrangements generate chimeric transforming oncogenes designated ret/ptc. By a combined immunohistochemical and RT-PCR approach, we analyzed, for ret/ptc oncogene activation, papillary thyroid carcinomas occurred in two FAP kindreds, both showing typical apc gene mutations. Kindred 1 had seven members affected by FAP, and among these, three patients showed papillary thyroid carcinomas. Kindred 2 had two patients, mother and daughter, affected by colonic polyposis; the 20-yr-old daughter showed also a papillary carcinoma. Here we report that ret/ptc1 oncogene was activated in two of the three papillary carcinomas of FAP kindred 1 and in the papillary carcinoma of FAP kindred 2. These findings document that loss of function of apc coexists with gain of function of ret in some papillary thyroid carcinomas, suggesting that ret/ptc1 oncogene activation could be a progression step in the development of FAP-associated thyroid tumors.

Adenomatous Polyposis Coli↗

PubMed1998

TPA induces a block of differentiation and increases the susceptibility to neoplastic transformation of a rat thyroid epithelial cell line.

The PC Cl 3 cell line is a well-characterized epithelial cell line of rat thyroid origin. This cell line retains in vitro the typical markers of thyroid differentiation: thyroglobulin (TG) synthesis and secretion, iodide uptake, thyroperoxidase (TPO) expression, and dependency on TSH for growth. Although the differentiated phenotype of thyroid cells has been relatively well described, the molecular mechanisms that regulate both differentiation and neoplastic transformation of thyroid cells still need to be investigated in detail. Protein kinase C (PKC), the target of tetradecanoylphorbol acetate (TPA), regulates growth and differentiation of several cell types. Here we show that treatment of PC Cl 3 cells with TPA induces an acute block of thyroid differentiation. TPA-treated PC Cl 3 cells are unable to trap iodide and the expression levels of thyroglobulin, TSH receptor, and TPO genes are drastically reduced by TPA treatment. This differentiation block is not caused by a reduced expression of one of the master genes of thyroid differentiation, the thyroid transcription factor 1 (TTF-1). TPA-treated PC Cl 3 cells display an increased growth rate indicating that, in addition to the differentiation block, TPA also significantly affects the growth regulation of thyroid cells. Finally, TPA treatment dramatically increases the number of transformation foci induced in PC Cl 3 cells by retroviruses carrying v-Ki-ras, v-Ha-ras, and v-mos oncogenes. These findings support the notion that the PKC pathway can influence proliferation, differentiation, and neoplastic transformation of thyroid cells in culture.

Animals↗

PubMed1998

Expression of the RET/PTC1 oncogene impairs the activity of TTF-1 and Pax-8 thyroid transcription factors.

The most frequent genetic alterations described thus far in human papillary thyroid carcinomas are somatic rearrangements of the RET proto-oncogene, which generate the chimeric RET/PTC oncogenes. We recently found that the expression of the RET/PTC1 oncogene blocked the expression of the thyroid-differentiated phenotype in rat thyroid epithelial cell line PC CI 3 (PC). Here, we show that this block occurs at a transcriptional level; indeed, the thyroid-specific thyroglobulin and thyroperoxidase gene promoters were inactive in PC-PTC cells. Specific transcription factors, namely, TTF-1 and Pax-8, regulate the expression of differentiated functions in thyroid cells. Here, we show that Pax-8 is expressed at reduced levels in PC-PTC cells and that its adoptive overexpression is unable to restore the activity of target promoters. In contrast, TTF-1 expression is unaltered in PC-PTC cells; however, by using a synthetic promoter that contains its specific target sequence, we demonstrate that TTF-1 is inactive in PC-PTC cells. We conclude that the RET/PTC1 oncogene alters the expression of the thyroid-differentiated phenotype by at least two different mechanisms, ie., down-regulation of Pax-8 protein and mRNA expression and impaired function of TTF-1 and Pax-8, which occurs at a posttranslational level.

Animals↗

PubMed1998

RET/PTC oncogene activation defines a subset of papillary thyroid carcinomas lacking evidence of progression to poorly differentiated or undifferentiated tumor phenotypes.

Malignant tumors of the thyroid gland vary considerably in aggressiveness, ranging from a well-differentiated, clinically indolent, to an undifferentiated, often lethal phenotype. Undifferentiated (anaplastic) thyroid tumors are supposed to be derived, through a process of progression, from previously differentiated neoplasms. A common genetic alteration in thyroid tumors is the rearrangement of the tyrosine kinase-encoding RET proto-oncogene, leading to the generation of chimeric RET/PTC oncogenes. To define the characteristics of the thyroid tumor subset with RET rearrangements, we have investigated its activation by a combined immunohistochemistry and reverse transcription-PCR approach in a series of 316 well-characterized thyroid tumors representative of the main diagnostic groups. RET activation was detected in 81 of 201 (40.3%) papillary carcinomas. It correlated with tumors exhibiting the "classic" morphological features of papillary cancer or with the microcarcinoma subtype (P = 0.017). RET activation in papillary carcinoma was not associated with clinical markers (such as large tumor size, extrathyroidal extension, or metastases) of increased morbidity. Follicular-type neoplasms (61 adenomas and 22 carcinomas), as well as the aggressive poorly differentiated (15 cases) or undifferentiated (anaplastic) carcinomas (17 cases), were negative. This study demonstrates that all thyroid carcinomas harboring activating RET rearrangements exhibit a well-differentiated phenotype, that of papillary carcinoma, and indicates that the subset of RET/PTC-positive papillary carcinomas do not progress to more aggressive, less differentiated tumor phenotypes.

Adolescent↗

PubMed1998

The risk of non-Hodgkin's lymphoma after Hodgkin's disease, with special reference to splenic treatment.

BACKGROUND AND OBJECTIVE: One of the consequences of the enormous improvement in survival rates of patients treated for Hodgkin's disease (HD) is the emergence in the long term of treatment-related complications, particularly secondary cancers. This study was undertaken to observe the occurrence of non-Hodgkin's lymphoma (NHL) in patients treated for HD and to identify the etiological role of various risk factors, especially spleen irradiation, in the pathogenesis of this illness. DESIGN AND METHODS: From 1972 to 1996, the Department of Radiation Oncology and the Hematology Section of "La Sapienza" University of Rome observed and analyzed the occurrence of NHL in 1,391 patients treated for HD. The average follow-up period was 84 months. For a more accurate calculation of the risk of the occurrence of NHL, the patients were first divided into 3 groups according to their initial treatment and also according to the total treatment they had received. Then, in order to establish the possible connection between NHL and splenic treatment the patients were also divided into 3 subgroups according to whether they had undergone splenectomy, splenic irradiation or neither of these. Two different methods of statistical analysis were used: (a) the cumulative risk (confidence interval) was evaluated in relation to treatment (initial and at the time of salvage) and (b) the Cox model was applied to identify the variables which play a role in the appearance of NHL. The cumulative risk of developing NHL was assessed using the Kaplan and Meier method. A multivariate analysis was performed using the Cox Proportional Hazard Model. RESULTS: A total of 20 cases of NHL were observed, appearing between 17 and 206 months after initial treatment. The cumulative risk was 0.8%, 1.8%, 2.6% and 3.5% at 5, 10, 15 and 20 years respectively. According to the multivariate analysis, significant risk factors were splenic irradiation and age (> 40 years). Splenic irradiation (vs no splenectomy/no splenic irradiation) showed a relative risk of 5.69, p = 0.0280, while age over 40 showed a relative risk of 3.05, p = 0.0152. INTERPRETATION AND CONCLUSIONS: From the results of this study, if appears that there is a possibility that splenic irradiation and age over 40 increase the risk of NHL in HD patients. Further studies are needed to investigate in greater depth the role of spleen irradiation in the occurrence of this illness.

Adult↗

PubMed1998

The risk of acute leukemia in patients treated for Hodgkin's disease is significantly higher aft [see bined modality programs than after chemotherapy alone and is correlated with the extent of radiotherapy and type and duration of chemotherapy: a case-control study.

BACKGROUND AND OBJECTIVE: Patients treated for Hodgkin's disease have an increased risk of developing subsequent acute leukemia. This co-operative study was conducted to assess the relative risk associated with several candidate factors including age, splenectomy, combined modality therapy and cumulative drug dose including alkylating agents and nitrosurea derivatives. DESIGN AND METHODS: This study evaluated the risk of acute leukemia according to pretreatment variables and therapy modalities among 1659 patients treated for Hodgkin's disease and followed for a median time of 10 years. Both case-control and actuarial risk studies were performed. Median age was 34 years (range: 12-83); 53% of patients were splenectomized. As to the overall therapy, 348 patients (21%) were given radiotherapy (RT) alone, 375 (23%) chemotherapy (CT) alone (including MOPP, MOPP + ABVD or MOPP + ABVD + lomustine); 936 (56%) received both CT and RT, either as primary or salvage treatment. RESULTS: The overall 15-year actuarial risk of leukemia was 4.2%; the hazard function curve showed two peaks of risk at the 3th and the 8th year from the initiation of therapy and no leukemia beyond the 12th year of follow-up. Risk of leukemia was 0.3% after RT alone, 2.8% after CT alone (2.2% after MOPP; 4.4% after MOPP + ABVD + lomustine), and 5.4% in patients given combined modality therapy (10.2% for RT + MOPP; 15.6% for RT + MOPP + lomustine). No leukemia occurred after ABVD alone and the risk was low (0.6%) when neither mechlorethamine nor lomustine were utilized. Patients who had received extended radiotherapy including abdomen and pelvis in addition to MOPP showed a significantly higher risk of leukemia compared to those given limited RT + MOPP (P = 0.01). Case-control analysis indicated advanced stage, type and duration (> 8 months) of CT and extension of RT as significant risk factors for leukemia. Compared to RT alone, the odds ratio was 5.9 after MOPP + extended RT, and 8 when a lomustine-containing regimen was used, as well. Neither age nor splenectomy were independent risk factors for leukemia; splenectomy was influential only when patients had been given MOPP chemotherapy, as well. INTERPRETATIONS AND CONCLUSIONS: Both case-control and actuarial analyses indicated that: a) combined modality therapy with MOPP and extensive RT (including abdomen and pelvis), and the use of lomustine added to the leukemogenic risk of MOPP alone; b) programs without mechlorethamine, procarbazine and lomustine were almost devoid of leukemogenic risk.

Abdomen↗

PubMed1997

Expression of the neoplastic phenotype by human thyroid carcinoma cell lines requires NFkappaB p65 protein expression.

We have investigated the role of the NFkappaB complex in the process of thyroid carcinogenesis by analysing thyroid carcinoma cell lines. A significant increase in p65 NFkappaB mRNA and protein expression, compared to normal thyroid cultures or tissue, was found in all of the cancer cell lines. Conversely, only a modest increase in the p50 NFkappaB mRNA and protein was found in most, but not all carcinoma cell lines. The block of p65 protein synthesis with specific antisense oligonucleotides greatly reduced the ability of two undifferentiated carcinoma cell lines to form colonies in agar and reduced their growth rate. On the other hand, no effect was observed in the same cell lines when treated with p50 specific antisense oligonucleotides. These inhibitory effects seem to be mediated by the suppression of c-myc gene expression, since treatment with antisense oligonucleotides for p65 gene interfered negatively with c-myc gene expression. Our results indicate that activation of the NFkappaB complex by overexpression of p65 plays a critical role in the process of thyroid cell transformation.

Down-Regulation↗

PubMed1997

Neoplastic transformation of rat thyroid cells requires the junB and fra-1 gene induction which is dependent on the HMGI-C gene product.

The expression of the high mobility group I (HMGI)-C chromatin component was shown previously to be essential for the establishment of the neoplastic phenotype in retrovirally transformed thyroid cell lines. To identify possible targets of the HMGI-C gene product, we have analyzed the AP-1 complex in normal, fully transformed and antisense HMGI-C-expressing rat thyroid cells. We show that neoplastic transformation is associated with a drastic increase in AP-1 activity, which reflects multiple compositional changes. The strongest effect is represented by the dramatic junB and fra-1 gene induction, which is prevented in cell lines expressing the antisense HMGI-C. These results indicate that the HMGI-C gene product is essential for the junB and fra-1 transcriptional induction associated with neoplastic transformation. The inhibition of Fra-1 protein synthesis by stable transfection with a fra-1 antisense RNA vector significantly reduces the malignant phenotype of the transformed thyroid cells, indicating a pivotal role for the fra-1 gene product in the process of cellular transformation.

Animals↗

PubMed1997

Thyroid cell transformation inhibits the expression of a novel rat protein tyrosine phosphatase.

We have isolated a rat thyroid cDNA encoding a novel rat receptor-type tyrosine phosphatase protein. This gene, on the basis of its homology to another tyrosine phosphatase, the recently isolated human DEP-1/HPTPeta, has been named r-PTPeta. In rat thyroid cells the r-PTPeta gene acts as a differentiation marker. Indeed, the block of thyroid cell differentiation induced by viral and cellular oncogenes is associated with the inhibition or marked reduction of the expression of this gene, and its expression is positively regulated by thyrotropin, the physiological stimulator of thyroid cell growth.

Amino Acid Sequence↗

PubMed1997

Expression of the RET receptor tyrosine kinase and GDNFR-alpha in normal and leukemic human hematopoietic cells and stromal cells of the bone marrow microenvironment.

The RET proto-oncogene product is a receptor tyrosine kinase representing the signal-transducing molecule of a multisubunit surface receptor complex for the glial cell line-derived neurotrophic factor (GDNF), in which a novel glycosyl-phosphatidylinositol (PI)-linked protein (termed GDNFR-alpha) acts as the ligand-binding component. We have analyzed expression of RET and GDNFR-alpha in purified normal hematolymphopoietic cells, leukemia/lymphoma cell lines, and 154 primary samples from patients with hematopoietic malignancies encompassing different lineages and differentiation stages. Relatively low amounts of RET mRNA were found in early CD34+ hematopoietic progenitors, but RET transcripts appeared to increase after myelomonocytic maturation. No expression of RET was found in peripheral blood and tissue B and T lymphocytes. Analysis of human myelomonocytic cell lines was overall consistent with results obtained on purified normal cells. Accordingly, RET expression was mainly confined to acute myeloid leukemias (AMLs) displaying either monocytic (French-American-British M4 and M5) or intermediate-mature myeloid (M2 and M3) phenotypes, being less frequently detected in early myeloid (M0 and M1) AMLs. In contrast, RET mRNA was sporadically detected in B-cell tumors, whereas, among T-cell malignancies, RET transcripts were mainly detected in cells of postthymic and mature T-cell phenotype. RET broad detection in primary tumors was not paralleled by the mutual expression of GDNFR-alpha, which was detected only in 2 isolated primary samples and in 3 leukemia/lymphoma cell lines. However, GDNFR-alpha transcripts, in the absence of RET mRNA, were found in normal bone marrow stromal cells (BMSC), in BM fibroblasts, and in two osteoblast cell lines previously described to support normal hematopoiesis. In the presence of GDNF-receptors derived from BMSC by PI-specific phospholipase C cleavage, GDNF efficiently bound RET-expressing AML blasts and was functionally active by reducing their clonogenic growth and triggering the monocytic maturation of leukemic cells.

Adipose Tissue↗

PubMed1997

The different RET-activating capability of mutations of cysteine 620 or cysteine 634 correlates with the multiple endocrine neoplasia type 2 disease phenotype.

Distinct point mutations of RET, a tyrosine-kinase receptor encoding gene, are responsible for the inheritance of multiple endocrine neoplasia type 2 syndromes (MEN2A and MEN2B) and familial medullary thyroid carcinoma (FMTC). In particular, MEN2A is a more complex and aggressive disease than FMTC, being characterized by pheochromocytomas and parathyroid alterations, in addition to medullary thyroid carcinomas. The mutations associated with MEN2A and FMTC affect one of five cysteine residues mapping in the extracellular domain of the Ret protein. However, recent studies have indicated that MEN2A and FMTC disease phenotypes correlate with the position of mutations in RET. Mutations of Cys-634 are more frequent in families with MEN2A, whereas Cys-620 mutations are very rarely found in MEN2A patients and, in contrast, are frequently found in FMTC patients. We have reported previously that mutations of Cys-634 constitutively activate the RET transforming potential by causing a disulfide bridge-mediated homodimerization. Here, we report that the mutation Cys-620 --> Tyr is able to cause a constitutive dimerization of Ret, with consequent activation of its kinase and transforming activities, to a lower extent than mutation of Cys-634. We suggest that the difference in ability to activate RET shown by mutations associated with FMTC and MEN2A represents the molecular basis of the phenotypic diversity between the two syndromes.

3T3 Cells↗

PubMed1997

Acute nonlymphocytic leukemia: onset after treatment for Hodgkin's disease.

This study was undertaken to examine the influence of various factors on the occurrence of acute nonlymphocytic leukemia (ANLL) in a group of longterm survivors of Hodgkin's disease (HD). From 1972 to 1992, 1045 patients with HD were assessed and treated at the Department of Radiation Oncology, the Institute of Radiology, and the Department of Human Biopathology, Hematology Section, University of Rome "La Sapienza". The average follow-up was 72 months. For a more accurate calculation of the risk of ANLL occurrence, the patients were first divided into three subgroups according to initial treatment and then according to the total treatment they had received. Moreover, to establish the probable connection between leukemia and splenic treatment the patients were also divided into three subgroups (splenectomy, splenic irradiation, and no splenectomy/no splenic irradiation). Sixteen cases of ANLL were recorded, giving an overall risk of 0.2% at 5 years and 3.4% at 20 years. In 12 patients overt leukemia was preceded by a myelodys-plastic syndrome. Five cases had evaluable chromosome analysis. Clonal chromosome abnormalities were demonstrated in two patients, whereas three patients showed an apparently normal karyotype. Bone marrow agar cultures were analyzed in two patients and were abnormal in both cases. In the radiotherapy (RT) group, the cumulative risk was 0.4% at 10 years and 3.2% at 15 and 20 years: in the chemotherapy (CT) group it was 1.2% at 10, 15, and 20 years; in the combined group it was 3.7% at 10 years and 4.9% at 15 and 20 years. In the multivariate analysis, MOPP treatment with or without RT is a statistically significant variable for ANLL occurrence (p = 0.009). This study demonstrates that splenic treatment does not lead to ANLL. Treatment with MOPP alone and with MOPP plus RT can increase the risk of ANLL.

Adult↗