Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation

The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.

A SUMOylation-defective MITF germline mutation predisposes to melanoma and renal carcinoma

So far, no common environmental and/or phenotypic factor has been associated with melanoma and renal cell carcinoma (RCC). The known risk factors for melanoma include sun exposure, pigmentation and nevus phenotypes; risk factors associated with RCC include smoking, obesity and hypertension. A recent study of coexisting melanoma and RCC in the same patients supports a genetic predisposition underlying the association between these two cancers. The microphthalmia-associated transcription factor (MITF) has been proposed to act as a melanoma oncogene; it also stimulates the transcription of hypoxia inducible factor (HIF1A), the pathway of which is targeted by kidney cancer susceptibility genes. We therefore proposed that MITF might have a role in conferring a genetic predisposition to co-occurring melanoma and RCC. Here we identify a germline missense substitution in MITF (Mi-E318K) that occurred at a significantly higher frequency in genetically enriched patients affected with melanoma, RCC or both cancers, when compared with controls. Overall, Mi-E318K carriers had a higher than fivefold increased risk of developing melanoma, RCC or both cancers. Codon 318 is located in a small-ubiquitin-like modifier (SUMO) consensus site (ΨKXE) and Mi-E318K severely impaired SUMOylation of MITF. Mi-E318K enhanced MITF protein binding to the HIF1A promoter and increased its transcriptional activity compared to wild-type MITF. Further, we observed a global increase in Mi-E318K-occupied loci. In an RCC cell line, gene expression profiling identified a Mi-E318K signature related to cell growth, proliferation and inflammation. Lastly, the mutant protein enhanced melanocytic and renal cell clonogenicity, migration and invasion, consistent with a gain-of-function role in tumorigenesis. Our data provide insights into the link between SUMOylation, transcription and cancer.

Significant contribution of large BRCA1 gene rearrangements in 120 French breast and ovarian cancer families

Genetic linkage data have shown that alterations of the BRCA1 gene are responsible for the majority of hereditary breast-ovarian cancers. However, BRCA1 germline mutations are found much less frequently than expected, especially as standard PCR-based mutation detection approaches focus on point and small gene alterations. In order to estimate the contribution of large gene rearrangements to the BRCA1 mutation spectrum, we have extensively analysed a series of 120 French breast-ovarian cancer cases. Thirty-eight were previously found carrier of a BRCA1 point mutation, 14 of a BRCA2 point mutation and one case has previously been reported as carrier of a large BRCA1 deletion. The remaining 67 cases were studied using the BRCA1 bar code approach on combed DNA which allows a panoramic view of the BRCA1 region. Three additional rearrangements were detected: a recurrent 23.8 kb deletion of exons 8-13, a 17.2 kb duplication of exons 3-8 and a 8.6 kb duplication of exons 18-20. Thus, in our series, BRCA1 large rearrangements accounted for 3.3% (4/120) of breast-ovarian cancer cases and 9.5% (4/42) of the BRCA1 gene mutation spectrum, suggesting that their screening is an important step that should be now systematically included in genetic testing surveys.

A phase III randomized trial comparing adjuvant concomitant chemoradiotherapy versus standard adjuvant chemotherapy followed by radiotherapy in operable node-positive breast cancer: final results

PURPOSE

To compare concomitant and sequential adjuvant chemoradiotherapy regimens in node-positive, operable breast cancer patients.

METHODS AND MATERIALS

This was a randomized, French, multicenter, phase III trial enrolling 638 eligible women with prior breast surgery and positive axillary dissection. Patients in Arm A received 500 mg/m2 5-fluorouracil, 12 mg/m2 mitoxantrone, and 500 mg/m2 cyclophosphamide, with concomitant radiotherapy (50 Gy +/- 10-20-Gy boost). Patients in Arm B received 500 mg/m2 5-fluorouracil, 60 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide, with subsequent radiotherapy. Chemotherapy was administered on Day 1 every 21 days for 4 cycles.

RESULTS

Median treatment durations were 64 and 126 days (Arms A and B, respectively), with no significant difference in overall or disease-free survival. Five-year locoregional relapse-free survival favored patients with conservative surgery (two thirds of the population), with less local and/or regional recurrence in Arm A than in Arm B (3% vs. 9%; p = 0.01). Multivariate analysis in this subgroup showed a 2.8-fold increased risk of locoregional recurrence with sequential chemoradiotherapy, independent of other prognostic factors (p = 0.027). Febrile neutropenia and Grade 3-4 leukopenia were significantly more frequent in Arm A. Subclinical left ventricular ejection fraction events at 1 year were more frequent with concomitant radiotherapy (p = 0.02).

CONCLUSIONS

Concomitant radiotherapy with adjuvant fluorouracil, mitoxantrone, and cyclophosphamide has significantly better locoregional control in node-positive breast cancer after conservative surgery and 50% shorter treatment, albeit with slightly more acute toxicity. With mitoxantrone no longer available for adjuvant breast cancer treatment, alternative concomitant chemoradiotherapy studies are needed.

Rapid hyperfractionated radiotherapy. Clinical results in 178 advanced squamous cell carcinomas of the head and neck

The authors present a series of 178 patients with Stage III or IV squamous cell carcinoma of the head and neck treated by rapid irradiation using multiple and small fractions per day. An initial group of 91 patients (G1) received a total dose of 72 Gy in 80 sessions and 10 days, according to the following split course schedule: J1 to J5, 36 Gy in 40 sessions, eight daily fractions of .9 Gy separated by 2 hours; J6 to J20, rest period; J21 to J25, same as in J1 except that the spinal cord was shielded. This protocol was altered for the following 87 patients (G2) by lessening the total dose to 60 to 66 Gy and the number of fractions to 60. The rest period was lengthened to 4 weeks. All patients but five completed the whole program and the minimal follow-up period was 24 months. At the end of irradiation, 121 patients achieved a total remission, but local recurrences occurred in 56%. Moreover, acute intolerance was considered as severe in 34% of G1 patients, and included extensive mucosal necrosis and bleeding. Although this rate was significantly reduced in G2 patients, late complications were observed in 20 of the 25 survivors, and included trismus, cervical sclerosis, and recurrent laryngeal edema. The crude survival rate is 13% at 2 years. Although this study was not randomized, this particular type of accelerated and hyperfractionated combination of irradiation did not really improve the clinical results in advanced carcinoma of the head and neck. Other schedules and probably other tumors, less extended, should be tested.

The contribution of large genomic deletions at the CDKN2A locus to the burden of familial melanoma

Mutations in two genes encoding cell cycle regulatory proteins have been shown to cause familial cutaneous malignant melanoma (CMM). About 20% of melanoma-prone families bear a point mutation in the CDKN2A locus at 9p21, which encodes two unrelated proteins, p16^INK4a and p14^ARF. Rare mutations in CDK4 have also been linked to the disease. Although the CDKN2A gene has been shown to be the major melanoma predisposing gene, there remains a significant proportion of melanoma kindreds linked to 9p21 in which germline mutations of CDKN2A have not been identified through direct exon sequencing. The purpose of this study was to assess the contribution of large rearrangements in CDKN2A to the disease in melanoma-prone families using multiplex ligation-dependent probe amplification. We examined 214 patients from independent pedigrees with at least two CMM cases. All had been tested for CDKN2A and CDK4 point mutation, and 47 were found positive. Among the remaining 167 negative patients, one carried a novel genomic deletion of CDKN2A exon 2. Overall, genomic deletions represented 2.1% of total mutations in this series (1 of 48), confirming that they explain a very small proportion of CMM susceptibility. In addition, we excluded a new gene on 9p21, KLHL9, as being a major CMM gene.

Single brain metastasis of non-small cell lung carcinoma. Study of survival among 54 patients

We studied 54 patients treated for non-small cell lung carcinoma with single brain metastasis presenting between 1980 and 1985. Better survival was obtained in cases of patients presenting a fair neurological condition who were treated by surgery. Histological condition and date of onet of metastasis had no significant influence on survival. Combined treatment of both primary lung tumour and brain metastasis was a favourable prognosis element, and surgical resection of both locations led to the best results in terms of duration and quality of survival.

Superimposition of computed tomography and single photon emission tomography immunoscintigraphic images in the pelvis: validation in patients with colorectal or ovarian carcinoma recurrence

A method of superimposing computed tomography (CT) and immunoscintigraphic (IS) single photon emission tomography (SPET) slices is presented and has been applied to 10 patients with suspected cancer recurrence. IS was performed with carcinoembryonic antigen (CEA)-specific indium-111 monoclonal antibodies (MoAbs) in 5 patients with colorectal cancer, and with OC125 111In-MoAbs in 5 patients with ovarian cancer. All patients had an abnormal CT image result in the pelvis, which was interpreted 5 times as recurrence, once as doubtful and four times as scar fibrosis. Recurrence was subsequently proven in all patients. Bone scintigraphy (BS) SPET was recorded at the same time as IS. No special technique was used during BS, IS or CT acquisition. CT images were fed into a computer using a CCD camera. Using the internal anatomical landmarks provided by the pelvic bone structures seen on CT and BS, an operator had to select corresponding fiducial points, which were used by the software to register the images. The final results were CT-BS and CT-IS superimposed images. CT-BS images were used for quality control. In all patients, the inspection of CT-BS and CT-IS showed that the registration process is accurate and assists in the co-interpretation of CT and IS images.

An entire exon 3 germ-line rearrangement in the BRCA2 gene: pathogenic relevance of exon 3 deletion in breast cancer predisposition

Background

Germ-line mutations in the BRCA1 and BRCA2 genes are major contributors to hereditary breast/ovarian cancer. Large rearrangements are less frequent in the BRCA2 gene than in BRCA1. We report, here, the first total deletion of exon 3 in the BRCA2 gene that was detected during screening of 2058 index cases from breast/ovarian cancer families for BRCA2 large rearrangements. Deletion of exon 3, which is in phase, does not alter the reading frame. Low levels of alternative transcripts lacking exon 3 (Δ3 delta3 transcript) have been reported in normal tissues, which raises the question whether deletion of exon 3 is pathogenic.

Methods

Large BRCA2 rearrangements were analysed by QMPSF (Quantitative Multiplex PCR of Short Fluorescent Fragments) or MLPA (Multiplex Ligation-Dependent Probe Amplification). The exon 3 deletion was characterized with a "zoom-in" dedicated CGH array to the BRCA2 gene and sequencing. To determine the effect of exon 3 deletion and assess its pathogenic effect, three methods of transcript quantification were used: fragment analysis of FAM-labelled PCR products, specific allelic expression using an intron 2 polymorphism and competitive quantitative RT-PCR.

Results

Large rearrangements of BRCA2 were detected in six index cases out of 2058 tested (3% of all deleterious BRCA2 mutations). This study reports the first large rearrangement of the BRCA2 gene that includes all of exon 3 and leads to an in frame deletion of exon 3 at the transcriptional level. Thirty five variants in exon 3 and junction regions of BRCA2 are also reported, that contribute to the interpretation of the pathogenicity of the deletion. The quantitative approaches showed that there are three classes of delta3 BRCA2 transcripts (low, moderate and exclusive). Exclusive expression of the delta3 transcript by the mutant allele and segregation data provide evidence for a causal effect of the exon 3 deletion.

Conclusion

This paper highlights that large rearrangements and total deletion of exon 3 in the BRCA2 gene could contribute to hereditary breast and/or ovarian cancer. In addition, our findings suggest that, to interpret the pathogenic effect of any variants of exon 3, both accurate transcript quantification and co-segregation analysis are required.

A one-step prescreening for point mutations and large rearrangement in BRCA1 and BRCA2 genes using quantitative polymerase chain reaction and high-resolution melting curve analysis

High-resolution melting (HRM) of DNA is a versatile method for mutation scanning that monitors the fluorescence of double-strand DNA with saturating dye. Performing HRM on a real-time thermocycler enables semiquantitative analysis (quantitative polymerase chain reaction, qPCR) to be associated to HRM analysis for detection of both large gene rearrangements and point mutations (qPCR-HRM). We evaluated this method of mutation screening for the two major breast and ovarian cancer susceptibility genes BRCA1 and BRCA2. Screening of these two genes is time-consuming and must include exploration of large rearrangements that represent 5% to 15% of the alterations observed in these genes. To assess the reliability of the HRM technology, 201 known nucleotide variations scattered over all amplicons were tested. The sensitivity of qPCR was evaluated by analyzing seven large rearrangements. All previously identified variants tested were detected by qPCR-HRM. A retrospective study was done with 45 patients: qPCR-HRM allowed all the variants previously tested by denaturing high-performance liquid chromatography to be identified. qPCR analysis showed three cases of allele dropout (due to a 104-bp deletion, SNP primer mismatch, and an Alu insertion). A prospective study was done with 165 patients allowing 22 deleterious mutations, 16 unclassified variants, and 2 rearrangements to be detected. qPCR-HRM is a simple, sensitive, and fast method that does not require modified PCR primers. Thus, this method allows in one step the detection of point mutation, gene rearrangements, and prevention of missing a mutation due to primer mismatch.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

Interaction of human cyclophilin hCyp-18 with short peptides suggests the existence of two functionally independent subsites

The binding of peptides, derived from the model substrate Suc-Ala-Ala-Pro-Phe-pNA, to the human cyclophilin hCyp-18 was investigated. HCyp-18 is able to bind 2-4-mer peptides as well as shorter para-nitroaniline (pNA) derivatives and pNA surrogates. Although Suc-Ala-Phe-pNA binds hCyp-18, only proline-containing peptides are able to block efficiently the peptidyl-prolyl cis/trans isomerase activity. Competition experiments strongly suggest the existence of two independent subsites: a S1' 'proline' subsite and a S2'-S3' 'pNA' subsite. The interaction at S2'-S3' requires either a Phe-pNA C-terminus or a Phe-pNA surrogate bearing an H-bond acceptor able to bind Trp121 and Arg148 simultaneously.

Hyperfractionated radiotherapy with or without misonidazole: results of a prospective randomized study in stage III-IV squamous cell carcinoma of the head and neck

From 1979 to 1980, 52 patients with Stage III-IV squamous cell carcinoma of the head and neck were included in a prospective randomized study on hyperfractionated radiotherapy with or without misonidazole. The radiotherapeutic schedule consisted of two weeks of treatment split by a rest-period of one month, 6 X 1.1 Gy fractions per day for 5 consecutive days (total dose: 2 X 33 Gy/30 f/5 d). Total dose of misonidazole was 12 g/m2 administered daily in 1.2 g/m2 fractions. The overall tolerance of misonidazole was good, with a neuropathy rate of 5.7%. Local control, recurrence and 3 year survival rates did not statistically differ between the two groups. The randomized trials published at the present time, including our own, suggest that misonidazole has no beneficial effect with classical, concentrated or multiple fractions per day radiotherapy.

GENESIS: a French national resource to study the missing heritability of breast cancer

Background

Less than 20 % of familial breast cancer patients who undergo genetic testing for BRCA1 and BRCA2 carry a pathogenic mutation in one of these two genes. The GENESIS (GENE SISter) study was designed to identify new breast cancer susceptibility genes in women attending cancer genetics clinics and with no BRCA1/2 mutation.

Methods

The study involved the French national network of family cancer clinics. It was based on enrichment in genetic factors of the recruited population through case selection relying on familial criteria, but also on the consideration of environmental factors and endophenotypes like mammary density or tumor characteristics to assess potential genetic heterogeneity. One of the initial aims of GENESIS was to recruit affected sibpairs. Siblings were eligible when index cases and at least one affected sister were diagnosed with infiltrating mammary or ductal adenocarcinoma, with no BRCA1/2 mutation. In addition, unrelated controls and unaffected sisters were recruited. The enrolment of patients, their relatives and their controls, the collection of the clinical, epidemiological, familial and biological data were centralized by a coordinating center.

Results

Inclusion of participants started in February 2007 and ended in December 2013. A total of 1721 index cases, 826 affected sisters, 599 unaffected sisters and 1419 controls were included. 98 % of participants completed the epidemiological questionnaire, 97 % provided a blood sample, and 76 % were able to provide mammograms. Index cases were on average 59 years old at inclusion, were born in 1950, and were 49.7 years of age at breast cancer diagnosis. The mean age at diagnosis of affected sisters was slightly higher (51.4 years). The representativeness of the control group was verified.

Conclusions

The size of the study, the availability of biological specimens and the clinical data collection together with the detailed and complete epidemiological questionnaire make this a unique national resource for investigation of the missing heritability of breast cancer, by taking into account environmental and life style factors and stratifying data on endophenotypes to decrease genetic heterogeneity.

Neoadjuvant chemotherapy and irradiation in multiple synchronous squamous cell carcinoma of the upper aero digestive tract

Twenty-four patients with multiple, synchronous carcinoma of the head and neck, lung or esophagus, were treated with induction chemotherapy followed by irradiation to involved areas. Chemotherapy regimen consisted of cisplatinum either alone, or in combination with 5-FU or etoposide. Subsequently, external radiotherapy, 60-65 Gy and 70-75 Gy to the mediastinum and the head and neck areas, respectively, was carried out. Following chemotherapy, three patients (12.5%) had a complete clinical remission in both cervical and mediastinal sites. That rate was significantly increased by radiotherapy (66%). Tolerance was fair or mild even though half of the patients needed a rest break during irradiation. Follow-up ranges from 24 to 38 months. The median survival is 12 months and the actuarial survival rates are 45% and 5% at 12 and 24 months, respectively. It is suggested that induction chemotherapy will not drastically improve the overall prognosis of multiple squamous cell carcinoma of the upper aero digestive tract and that external irradiation remains a major part of treatment which should not be reduced in treated volumes, or in total dose delivered.

Squamous cell carcinoma of the upper aero-digestive tract in women

Between 1970 and 1985, 95 women presenting carcinomas of the oral cavity, pharynx or larynx, were treated at the Institut Jean-Godinot. Classification of these patients according to age shows a bimodal curve and the existence of two different populations. The main difference between groups appears to be the existence or not of tobacco intoxication. According to this criteria, the two groups of patients are statistically different in mean age (nonusers 16 years older than users, p less than 0.01) and in the site of the primary, with an excess of carcinomas of the oral cavity in the nonusers group (p less than 0.01). In contrast, no difference was found in the locoregional extension of the tumor (TNM), in the modalities and result of treatment or in the evolution and survival of patients.

The use of a concomitant electron boost (field in the field technique) in large cervical node metastases over a shortened period

Seven patients with large cervical node metastases were treated at the Institut Jean-Godinot using a particular scheme of accelerated irradiation. Conventional Cobalt-60 radiotherapy was prophylactically delivered to extended volumes of the neck (50 Gy in 25 fractions over 5 weeks). Within the fields of cobalt irradiation, an electron beam field was added to increase the daily dose from 2 to 3 Gy (Fletcher's field in the field technique). The increment of dose was limited to nodal area. Since no interval separated the two irradiations, involved areas were considered to receive 70 Gy in 25 fractions over 5 weeks and non-clinically involved areas to receive 50 Gy in 25 fractions over 5 weeks. In all the cases, the malignant mass diameter exceeded 5 cm. Acute tolerance was good and no major late injury was observed during the 18 months minimum follow-up period. At the end of the treatment, a complete disappearance of the tumor was observed in six out of seven cases. At the present time, four patients are still alive without evidence of disease. Slight acceleration of irradiation by the use of a concomitant electron boost is easily feasible and may provide an improvement in local control and therapeutic ratio of large cervical malignant masses in the neck.

[Intraoperative radiotherapy of ORL cancers. Review of the literature]

An optimal treatment of head and neck carcinoma is to be targeted at obtaining a good local control of the disease. Intraoperative radiotherapy is one of the means of increasing the irradiation dose in the tumoral volume. It appears particularly suitable for initial treatment of locally advanced head and neck lesions and treatment of recurrence of non irradiated tumors.

[Cancer of the esophagus after mediastinal radiotherapy for Hodgkin's disease. Apropos of a case]

Malignant solid tumors induced by radiotherapy for Hodgkin's disease are uncommon. We report one case of thoracic esophageal squamous carcinoma diagnosed 19 years after mediastinal irradiation. The criteria usually accepted for the diagnosis of radiation cancer were all present in this case. An oesophagectomy was performed and the patient made a good recovery from the operation.

[Partial regression of Barret esophagus with high grade dysplasia and adenocarcinoma after photocoagulation and endocurietherapy under antisecretory treatment]

Barrett's oesophagus is a premalignant condition. The possibility of eradicating at least partially the metaplastic epithelium has been reported recently. In this case report, a patient with Barrett's oesophagus complicated by high grade dysplasia and focal adenocarcinoma was treated by Nd:Yag laser then high dose rate intraluminal irradiation while on omeprazole 40 mg/day. A partial eradication of Barrett's oesophagus and a transient tumoural regression were obtained. Histologically, residual specialized-type glandular tissue was observed beneath regenerative squamous epithelium. Four months after intraluminal irradiation, a local tumoural recurrence was detected while the area of restored squamous epithelium was unchanged on omeprazole 40 mg/day. This indicates that physical destruction of Barrett's oesophagus associated with potent antisecretory treatment can induce a regression of the metaplastic epithelium, even in presence of high grade dysplasia. The persistence of specialized-type glands beneath the squamous epithelium raises important issues about its potential malignant degeneration.