P14.58 Efficacy and safety of lomustine versus fotemustine as first and second line treament in relapsed glioblastoma patients

BACKGROUND

Glioblastoma (GB) is the most aggressive primary brain tumour. Despite the survival benefit associated with adjuvant therapy, most of patients (pts) relapse after initial therapy. Nitrosoureas (NU) are the standard treatment at relapse in Europe. Both fotemustine (FM) (Addeo schema) and lomustine (LM) (administered orally every 6 weeks) are used in this context.

MATERIAL AND METHODS

This retrospective cohort study included pts diagnosed with GB treated with NU at relapse in four Catalonia hospitals from 2010 to 2020. Clinical and pathological data were collected from medical records. We analysed 6months-progression-free survival (6m-PFS), progression-free survival (PFS) and overall survival (OS) from the start of NU to progression or death respectively. Differences in toxicity grade using CTCAE v5.0 were analysed globally as ‘non-toxicity’, ‘mild toxicity (grade 1 or 2)’ and ‘high toxicity (grade 3 or 4)’.

RESULTS

We identified 236 GB pts with a median age of 58 years old. 29% of the pts presented MGMT promotor methylation and only 3%(n=7) had IDH mutation. After a median follow-up of 20 months, 94% of the pts were dead at the time of the analyses. At first line, 83 pts were treated with FM and 18 with LM. Pts treated with FM had better performance status (PS) than those treated with LM (p=.010). Median PFS was 2 months and 6m-PFS was 12% vs 6% in FM and LM group respectively (p=.87). Median OS was 3 months with LM vs 6 months with FM, with no statistically significant differences even adjusted for prognostic factors (p=.79 HR:0.9 CI 95% 0.41–1.96).At second line, 78 were treated with FM and 24 with LM, no differences between groups. Median PFS was 2 months in both groups and median OS was 3 vs 5 months for pts treated with LM vs FM respectively, with no significant differences. 6m-PFS was 13% for LM vs 0% for the FM group (p=.39).Pts received a mean of 1.7 cycles (every 6 weeks) and 4.1 cycles (every 2 weeks) in LM and FM group, respectively. Thrombocytopenia was the most common serious side-effect, with a higher proportion of grade 1–2 toxicity in the FM group (p=.03) that also required more treatment delays (p=.01).

CONCLUSION

Despite being retrospective study and a few pts were treated with LM, there were no differences neither in PFS nor in OS in pts treated with LM vs FM at first or second line. Higher G1-2 thrombocytopenia was shown in the FM group probably due to a higher number of hematology samples collected.

Exclusion of mosaicism in Spanish haemophilia A families with inversion of intron 22

Inversion of intron 22, the most frequent mutation event in haemophilia A (HA), was tested in our HA families to diagnose the females at risk of being carriers, to trace the origin of the mutation and to investigate the presence of germinal or somatic mosaicism. A total of 166 females belonging to 54 families with inversion, were analysed. All but one of the mothers tested were carriers and the inversion originated almost exclusively in male germ cells. Somatic or germline mosaicisms were excluded in 53 of these women and in 20 grandfathers, suggesting that such mosaicisms may be a rare event in families with inversion of intron 22.

Is thiopurine methyltransferase genetic polymorphism a major factor for withdrawal of azathioprine in rheumatoid arthritis patients?

OBJECTIVE

To determine whether the presence of thiopurine methyltransferase (TPMT) alleles associated with reduced or absent activity of thiopurine methyltransferase is a major factor for withdrawal of azathioprine (AZA) in rheumatoid arthritis (RA) patients.

METHODS

The TPMT genotype, including the variable number of tandem repeats (VNTR) pattern in the 5' untranslated region, was analysed in 111 patients with long-standing RA. Azathioprine (AZA) therapy was used in 40 patients (36%) as a disease-modifying anti-rheumatic drug.

RESULTS

Seven out of 111 RA patients (6.3%) were carriers of a mutant allele, TPMT3A (G(460)-->A, A(719)-->G) being the mutant allele observed most frequently. In the group of 40 AZA-treated patients, therapy was discontinued in six patients because of side-effects and in 26 patients because of lack of efficacy. Three patients presented moderate side-effects and were homozygous for the wild-type TPMT allele, whereas the remaining three patients, who developed gastrointestinal effects with severe nausea and vomiting, were TPMT3A carriers.

CONCLUSION

In this observational study, the absence of response, probably due to the low-dose scheme used, was the major cause of AZA withdrawal in our series of RA patients. TPMT genotyping may allow the use of high doses of AZA in patients with normal TPMT alleles to improve the efficacy of this immunosuppressive drug. Our data support the relationship between gastrointestinal intolerance and thiopurine metabolic imbalance.

Modifier genes in haemophilia: their expansion in the human genome

Mutations in factor VIII and IX genes have a determinant effect on the severity of haemophilia. Modulation of clinical manifestations depends on other genetic factors, including modifier genes. In the context of haemophilia, such genes could be the ones involved in thrombophilia. Factor V Leiden and prothrombin 20210A were studied as possible phenotypic modifiers. Inhibitor development after therapeutic factor replacement depends on the type of mutation and on the genetic factors related to the immune response of each patient. The study of all these variants in haemophiliacs constitutes an important step in prevention, prognosis and therapeutic alternatives of the disease.

BRCA2 mutation analysis of 87 Spanish breast/ovarian cancer families

BACKGROUND

It is estimated that about 5% -10% of breast cancer (BC) cases is due to inherited predisposition. Early works reported that 45%-50% of site-specific BC families had BRCA1 mutations and 25%-35% BRCA2 mutations. However, these percentages could have been overestimated and likely vary among the populations studied.

PATIENTS AND METHODS

We analysed the BRCA2 gene in 87 Spanish breast/ovarian cancer families in which the BRCA1 mutation screening was negative.

RESULTS

We detected 15 (17.2%) disease-causing mutations and 11 polymorphisms and unclassified variants. Four mutations were recurrent, and five were novel. Seven (47%) mutations were found in site-specific female BC families, five (33%) in families with OC cases, and three (20%) mutations in families with male BC cases. There was incomplete penetrance of the mutations in some families, and considerable phenotypic variations with respect to the age of diagnosis and cancer types.

CONCLUSIONS

The percentage of mutations detected reinforces the possibility that some of these families have mutations in genes other than BRCA1 or BRCA2 that confer lower BC risks.

[Clinical and pathological characteristics and clinical course of patients with breast cancer and BRCA1/BRCA2 mutations]

BACKGROUND

Clinico-pathological differences between BRCA1 or BRCA2 mutation-associated breast cancer (BC) and sporadic BC are little known.

PATIENT AND METHODS

We analysed the clinico-pathological characteristics and clinical follow-up of 30 patients with BC. BRCA1 and BRCA2 mutations were detected by SSCP and PTT.

RESULTS

There were no differences in age, size or nodal status at the time of diagnosis. Mammography features were more heterogeneous in BRCA2 than in BRCA1 BC. All BRCA1 mutation-associated BC corresponded to infiltrating ductal carcinomas (20% medullary carcinomas) with a more aggressive pathological behavior. The frequency of local recurrences was 14% in BRCA1 and 20% in BRCA2. Contralateral BC and ovarian cancer (OC) were observed in 27% and 20% of BRCA1 cases, respectively, and 6% and 6% of BRCA2 cases. The median follow-up in BRCA1 and BRCA2 BC was 131 and 54 months, respectively.

CONCLUSIONS

There were no differences in age at diagnosis and stage between BRCA1 and BRCA2 breast cancer. The mammographic pattern in BRCA2 was more heterogeneous. BRCA1 mutations were associated with more aggressive histopathologic findings and a higher risk of a second BC and OC.

The R71G BRCA1 is a founder Spanish mutation and leads to aberrant splicing of the transcript

In a BRCA1 screening in familial breast cancer carried out in different centres in Spain, France, and United Kingdom, a missense mutation 330A>G which results in a Arg to Gly change at codon 71 (R71G) was independently identified in 6 families, all of them with Spanish ancestors. This residue coincides with the -2 position of the exon 5 donor splice site. We further investigated the effect of this base substitution on the splicing of BRCA1 mRNA. The sequence analysis of the cDNA indicated that 22 bp of exon 5 were deleted, creating with the first bases of exon 6 a termination codon at position 64, which results in a truncated protein. The BRCA1 haplotype of the R71G carrier patients and Spanish controls was analysed by use of six microsatellites located within or near BRCA1. Our results are consistent with the possibility that these families shared a common ancestry with BRCA1 R71G being a founder mutation of Spanish origin.

Conditions for single-strand conformation polymorphism (SSCP) analysis of BRCA1 gene using an automated electrophoresis unit

The single-strand conformation polymorphism procedure has been applied in routine testing for hereditary diseases and cancer. However, temperature, running time, gel composition, fragment length, etc. can influence its sensitivity. Mutation detection in the clinical setting depends on the development of automated technology, especially for large genes such as the breast cancer gene BRCA1. We analysed DNA samples with BRCA1 mutations in an automated system (GenePhor System; Amersham-Pharmacia Biotech, Uppsala, Sweden). The concentrations of DNA template and PCR primers, the effect of chilling after denaturation, and the temperature and time of the electrophoresis were investigated. All band-shifts were detected by electrophoresis at 5 degrees C for 2 h 15 min. Concentrations of DNA and samples used in the PCR did not affect the SSCP pattern, but chilling the PCR product in ice after denaturation was required. The type and position of mutation in the fragments did not influence the probability of a mobility shift, although SSCP analysis was more sensitive for fragments shorter than 350 bp. This automated SSCP method meets the requirements of fast turnaround and sensitivity and can be readily adapted to the screening of large genes such as BRCA1.

[Aplasia after azathioprine administration: role of the thiopurine methyltransferase genetic polymorphism]

BACKGROUND

Azathioprine is an immunosuppressor drug widely used in the treatment of autoimmune diseases. Adverse effects during treatment are related to the activity of thiopurine methyltransferase (TPMT), an enzyme which plays a role in azathioprine metabolism. The presence of the allelic variants of the TPMT gene allows us to classify patients into three different groups: high, moderate and low risk of myelosuppression after receiving standard doses of azathioprine.

PATIENTS AND METHODS

Study of the allelic variants of the TPMT gene in the positions 460 and 719 with PCR methods in a patient with Crohn's disease, who developed aplasia after receiving azathioprine. The study was extended to his relatives.

RESULTS

The patient under study carried the most frequent variant allele of the TPMT gene associated with low enzymatic activity. The mother and one sister of the patient were also carriers of this allelic variant.

CONCLUSIONS

Genotyping the allelic variants of the TPMT gene is a useful method to identify patients at moderate or high risk of myelosuppression after administration of azathioprine.

Allelic variants of the thiopurine S-methyltransferase deficiency in patients with ulcerative colitis and in healthy controls

OBJECTIVE

Thiopurine S-methyltransferase (TPMT) is a cytosolic enzyme that catalyzes the inactivation of mercaptopurine, azathioprine, and thioguanine. The genetic polymorphisms in the TPMT gene that regulate TPMT activity are inherited as an autosomal recessive trait and patients with genetically determined low levels of TPMT activity develop severe myelosuppression when treated with standard doses of the above-mentioned drugs. We have analyzed the frequencies of the allelic variants of the TPMT gene in a white European population of healthy blood donors from Spain and The Netherlands, and in a group of patients suffering from ulcerative colitis (UC) with a similar genetic background.

METHODS

Two hundred and thirteen unrelated healthy individuals (HC) and 146 UC patients were typed for the polymorphic sites at positions 460 (G-->A) and 719 (A-->G) of the TPMT gene using specific polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) methods.

RESULTS

There were no significant differences between the allele frequencies observed in the group of UC patients and those of the control group (10% of cases were heterozygous carriers of a TPMT mutant allele). The most frequent mutant allele in both UC and HC groups was TPMT3A (A460-->G719) (60% of carriers). TPMT3B (A460-->A719) and TPMT3C (G460-->G719) alleles were more often found in our study than in previously reported studies, reflecting the different genetic backgrounds of the European populations analyzed.

CONCLUSIONS

Genotyping methods provide a simple and reliable screening to identify patients with a high risk of developing severe bone marrow toxicity if treated with thiopurine drugs. In UC patients, TPMT genotype should be determined before the initiation of azathioprine therapy.

Carboplatin-gemcitabine treatment of patients with transitional cell carcinoma of the bladder and impaired renal function

INTRODUCTION

Bladder cancer is a frequently occurring tumour in Spain and usually affects elderly patients with renal impairment. The development of new combination therapies for such patients is thus of vital importance.

PATIENTS AND METHODS

Between 1997 and 1998, 17 patients with locally advanced non-surgical or metastatic bladder tumours were treated at our centres. Treatment consisted of 1,000 mg/m(2) of gemcitabine administered on days 1 and 8, and carboplatin (area under the concentration curve = 5) on day 1, every 21 days.

RESULTS

The mean age of the patients [4 females (26%) and 13 males] was 69 years (range: 54-78 years). The average Karnofsky performance status was 80% (range: 50-100%). Mean creatinine clearance was 45.4 ml/min (range: 21-55 ml/min). There were 2 complete responses, 7 partial responses (RO: 56%; range 31-81%), 6 patients had stable disease and 1 disease progression. Haematological toxicities were as follows: grade I anaemia in 2 patients, grade III in 3; grade I granulocytopenia in 2 patients, grade III-IV in 4 patients; grade III thrombocytopenia in 3 patients. Toxic death occurred in the course of one grade IV neutropenic event. Non-haematological toxicities were as follows: grade I-II vomiting in 3 patients and grade III in 1. One patient had grade III hepatic toxicity. One patient had grade III renal toxicity, and 3 patients grade II alopecia.

CONCLUSIONS

The above-mentioned treatment has low toxicity, is easy to administer and offers promising results in this group of patients.

BRCA2 germ-line mutations in Spanish male breast cancer patients

BACKGROUND

Mutations in the BRCA2 gene account for the majority of the families with male and female breast cancer cases, and a number of BRCA2 mutations have been reported in males with breast cancer. The aim of this study was to characterise BRCA2 germ-line mutations in Spanish male breast cancer patients.

PATIENTS AND METHODS

We screened DNA from 11 affected men and 6 women with breast cancer (BC) who had an affected male relative (father or brother). Exons 2-9 and 12-27 were screened by SSCP, and exons 10 and 11 were screened by PTT. PCR products with a variant band were sequenced.

RESULTS

Three BRCA2 frameshift mutations were identified (17.6%): the 3374delA in codon 1049 (exon 11), 6857delAA in codon 2010 (exon 11), and 9254delATCAT in codon 3009 (exon 23). These mutations were present in patients with affected first-degree relatives (3 of 9, 33%). The proportion of male patients with a family history of BC in at least one first-degree relative was 53%.

CONCLUSIONS

There is an association between BRCA2 mutations and male breast cancer, especially in those with a family history of BC. The high prevalence of BRCA2 mutations among males should be considered when estimating risk for female relatives. All new male cases of BC should be regarded as being possibly inherited and should be fully investigated.

BRCA1 mutation analysis in 83 Spanish breast and breast/ovarian cancer families

A group of 83 Spanish BC/OC families were analysed for BRCA1 germ-line mutations. Analysis of the entire coding sequence was carried out by SSCP and PTT. We identified 5 frameshift mutations: 185delAG (2 times), 189insTGTC, 1241delAC, and 5537delA and 3 missense mutations in BRCA1: 330A > G, 1240C > T, and 5263G > A. The 185delAG mutation was identified in 2 families. One of them was the only Gypsy family participating in our study. All carriers shared the known founder haplotype, although they did not have any Jewish ancestry. Three frameshift mutations were found among the 14 families with 3 or more BC cases and 1 or more OC, which results in a higher percentage (21.4%) of BRCA1 mutations in this group of high risk families. Two missense mutations were found in families with 2 or 3 BC and no OC, indicating a low proportion (4.8%) of mutations in these families. There was no association between bilateral BC and a mutation carrier status. The frequency of BRCA1 involvement is lower than that of any other country hitherto reviewed. Our results highlight the influence of geographical and ethnic origin of the population studied.

Two contiguously located germline BRCA1 mutations in a Spanish early-onset breast cancer family

We identified two BRCA1 mutations in a high risk breast cancer family: the missense 1240 C > T (Thr > Ile) and the 1241delAC at codon 374, which results in a stop at codon 376. Both were contiguously located in the same BRCA1 gene, in a motif of 11 amino acids, which is highly conserved across human, canine and murine species. The presence of missense mutations in this motif in breast-cancer families suggests an important functional role for this protein region and a potential deleterious effect of the 1240C > T mutation.

Prevalence of BRCA1 and BRCA2 Jewish mutations in Spanish breast cancer patients

We screened the 185delAG and 5382insC (BRCA1) and the 6174delT (BRCA2) mutation in 298 Spanish women with breast cancer. Two women (one with Sephardic ancestors) presented the 185delAG mutation and the same haplotype reported in Ashkenazim with this mutation. This suggests a common origin of the 185delAG in both Sephardic and Ashkenazi populations.

[The identification of a new mutation in the BRCA2 gene by protein truncation analysis in a Spanish family with hereditary breast cancer]

The BRCA2 mutations are implicated in a high percentage of hereditary breast cancer cases. We report a novel mutation in a Spanish breast cancer family. We analyzed DNA samples of the proband and of the living first and second degree relatives. Exon 11 of BRCA2 gene were screened by the protein truncation test and direct sequencing. We identified a novel mutation, 6857 delAA, in three affected women, diagnosed of breast cancer at 29, 51 and 45 years of age, respectively, and in a healthy male. The BRCA2 mutation seems to be implicated in the development of early-onset breast cancer cases in this family. Identification of this novel mutation adds to the information on BRCA2 gene in hereditary breast cancer in Spanish population.

[Mutations in the BRCA1 gene in young Spanish women with breast cancer]

BACKGROUND

Germline mutations in the BRCA1 gene have been associated with familial breast/ovarian cancer. Furthermore, women diagnosed of early-onset breast cancer have a higher probability of being carriers of BRCA1 mutations. Our aim was to know prevalence of BRCA1 mutations in women with breast cancer diagnosed before 40 years.

PATIENTS AND METHODS

We analyzed genomic DNA samples of 159 women with early-onset breast cancer. Ten fragments of BRCA1 gene covering the 36% of cases with mutations described in the literature were screened. Analysis involved polymerase chain reaction (PCR), single-strand conformation polymorphisms (SSCP) and direct sequencing.

RESULTS

Three germline BRCA1 mutations were identified, one of them not previously described. Two mutations were found in women with familial history of breast cancer. Five additional rare variants and polymorphisms were also detected.

CONCLUSIONS

The absence of recurrent mutations or mutations detected in other countries, except for the 185delAG mutation, present in Ashkenazim population, shows the influence of ethnic and geographic origin of population studied, and illustrates the difficulties of establishing DNA-based screening tests for hereditary breast cancer.

Inversion of intron 22 in isolated cases of severe hemophilia A

Inversion involving intron 22 is the commonest type of mutation causing severe hemophilia A (HA). We investigated 15 families with isolated cases and 5 families with two or three brothers as the only affected members with hemophilia A, in order to determine the carrier status of the mothers, the origin of the mutation and the presence of germinal mosaicism. Our results show that all mothers tested were carriers of the inversion. In addition, three families whose unique hemophilic member was not available for analysis, were screened for the inversion. In one of these last families, the mother was diagnosed as a carrier and her sister and her niece as non-carriers. DNA haplotype analysis in 8 families with grandparents available for study demonstrated that the inversion originated almost exclusively in male germ cells. These findings have important relevance for genetic counselling in families with an isolated case or to exclude germinal mosaicism. Inversion analysis should constitute the first step in molecular diagnosis of severe hemophilia A.

Alanine as a lipogenic precursor in isolated hepatocytes from obese Zucker rats

Isolated hepatocytes from obese Zucker rats showed an increased capacity for lipid synthesis measured as the incorporation of 3H2O into lipid fractions. In addition lipid synthesis from 1 mM U-14C-alanine was elevated as compared to those isolated from their lean counterparts. On these lines, the amino acid was a better lipogenic substrate than U-14C-lactate at 5 mM concentration. Insulin increased lipid synthesis from the amino acid in the lean animals while showed no effects on this parameter in the obese. While the hepatocytes from the lean animals used to a similar extent U-14C-alanine carbon from 14CO2 production, lipid synthesis and 14C-glycogen incorporation, those from the obese animals showed a decreased oxidation and glycogen incorporation while an augmented lipid synthesis. The total amount of the amino acid taken up by the obese animals was also significantly elevated. Conversely, the metabolic fate of U-14C-leucine was very similar between the two groups. It can be concluded that in the obese Zucker rat alanine is a very important amino acid which contributes to sustain the high liver hyperlipogenesis previously described.

Amino acid metabolism enzyme activities in the obese Zucker rat

Hepatic serine dehydratase activity was significantly lower in the obese Zucker rats. In both skeletal muscle and kidney adenylate deaminase showed a lower activity in the obese animals. In the small intestine the activity of glutamate dehydrogenase was increased while that of glutamine synthetase was reduced. No changes were found in the enzymatic activities of white adipose tissue while those found in brown adipose tissue were lower for glutamine synthetase. Starvation resulted in increase in liver serine dehydratase in the lean animals and in aspartate transaminase in both lean and obese. Kidney aspartate transaminase and glutamine synthetase were increased with starvation in the lean rats while kidney adenylate deaminase and small intestine glutamine synthetase and branched-chain amino acid transaminase were increased with starvation in the obese animals. In brown adipose tissue starvation caused an increase in branched-chain amino acid transaminase in the lean rats while it significantly lowered the adenylate deaminase and increased branched-chain amino acid transaminase in the obese rats.

Amino acid metabolism in several tissues of the obese Zucker rat as indicated by the tissue accumulation of alpha-amino[1-14C]isobutyrate

Measurements of the tissue accumulation of alpha-amino[1-14C]isobutyrate [1-14C]AIB in lean (+/?) and obese (fa/fa) Zucker rats showed an augmented tissue/plasma ratio in the liver of the obese animals. In contrast, brown adipose tissue AIB accumulation was lower in the fa/fa animals. In response to a 24 h starvation period AIB accumulation was significantly elevated in the liver and plasma of the lean animals and was unchanged in the liver of the fa/fa animals. The circulating concentration of alanine and branched-chain amino acids was elevated in the fa/fa animals as compared to their lean counterparts. These observations suggest that amino acid uptake is not involved in the impaired muscle development observed in the obese Zucker rat and that the ability of brown adipose tissue for amino acid utilization is decreased in the obese animals suggesting that this may partially explain the impaired thermoregulatory capacity observed in brown adipose tissue of obese Zucker rats.

[Efficacy of sucralfate in the prophylaxis of diarrhea secondary to acute radiation-induced enteritis. Preliminary results of a double-blind randomized trial]

BACKGROUND

Pelvic radiation therapy is usually associated with intestinal symptoms, especially diarrhea. Sucralfate has been demonstrated to be effective in peptic ulcers, and seems to provide some benefits in chemotherapy induced mucositis and radiogenic rectitis and enteritis.

METHODS

Thirty-four patients between 20-80 years of age, without diarrea and with a Karnofsky index greater than 60%, undergoing whole pelvic irradiation (46 Gy total dose, 2 Gy/day, 5 days/week) have been randomized to receive: sucralfate (1g/6h) (18 patients) or placebo (16 patients) during the treatment period and 3 weeks later.

RESULTS

The statistical analysis of the clinical records show that patients receiving sucralfate do better during the whole treatment period (p = 0.03), and they need other complementary measures against diarrhea, as diet (p = 0.03) or pharmacologic support (p = 0.002), later in the course of the radiotherapy. Nevertheless, the incidence and severity of diarrea and other associated simptoms show no differences between both groups.

CONCLUSIONS

Sucralfate increases the enteric tolerance during pelvic irradiation in cancer patients.