Factors associated with enrolment in clinical trials among women with early-stage breast cancer.

BACKGROUND: Clinical trials allow development of innovative treatments and ameliorate the quality of clinical care in oncology. Data show that only a minority of patients are enrolled in clinical trials. We assessed enrolment in clinical trials and its correlates among women with early breast cancer. METHODS: We included 9516 patients with stage I-III breast cancer from the multicenter, prospective CANTO study (NCT01993498), followed-up until year 4 (Y4) post-diagnosis. We assessed factors associated with enrolment using multivariable logistic regression. In exploratory, propensity score matched analyses, we used multiple linear regression to evaluate the relationship of enrolment in clinical trials with the European Organisation for Research and Treatment of Cancer Quality Of Life (QoL) questionnaire (EORTC QLQ-C30) Summary Score and described clinical outcomes (distant disease event, invasive disease event, and death by any cause) according to enrolment. RESULTS: Overall, 1716 patients (18%) were enrolled in a clinical trial until Y4 post-diagnosis of breast cancer. Socioeconomic factors were not associated with enrolment. Centres of intermediate volume were most likely to enrol patients in clinical trials [versus low volume, odds ratio 1.45 (95% confidence interval (CI) 1.08-1.95), P = 0.0124]. Among 2118 propensity score matched patients, enrolment was associated with better QoL at Y4 (adjusted mean difference versus not enrolled 1.37, 95% CI 0.03-2.71, P = 0.0458), and clinical outcomes (enrolled versus not enrolled, distant disease event 7.3% versus 10.1%, P = 0.0206; invasive disease event 8.2% versus 10.5%, P = 0.0732; death by any cause 2.8% versus 3.7%, P = 0.2707). CONCLUSIONS: In this large study, one in five patients enrolled on a clinical trial until Y4 after diagnosis of early breast cancer. Geographical and centre-related factors were significantly associated with enrolment in clinical trials. Inclusion in clinical trials seemed associated with improved QoL and clinical outcomes. Access to innovation for early-stage breast cancer patients should be encouraged and facilitated by overcoming organizational and geographical barriers to recruitment.

Enrollment of older metastatic breast cancer patients in first-line clinical trials: 9-year experience of the large-scale real-life multicenter French ESME cohort.

PURPOSE: Older cancer patients are underrepresented in clinical trials. We aimed to evaluate the enrollment of older women aged 70 years old (yo) or over with metastatic breast cancer (MBC) in clinical trials. METHODS: We used the national Epidemio-Strategy and Medical Economics MBC Data Platform, a French multi-center real-life database. We selected MBC women over 70yo, without central nervous system metastases, with at least one line of systemic treatment, between January 1st, 2008 and December 31st, 2016, and had no other cancer in the 5 years before MBC. The primary objective was to evaluate the proportion of patients enrolled in clinical trials according to their age. Secondary objective was to identify variables associated with enrollment in older ones. RESULTS: 5552 women were aged ≥ 70 (median 74yo; IQR 72-77). 14,611 were less than 70. Of the older ones, 239 (4%) were enrolled in a clinical trial during first line of treatment, compared with 1529 (10.5%) for younger ones. Multivariable analysis of variables predicting for enrollment during first line of treatment in older patients were younger age (OR 0.50 [95%CI 0.33-0.76] for the 80-85yo class; OR 0.17 [95%CI 0.06-0.39] for the 85yo and more class), good ECOG Performance Status (PS 0-1) (OR 0.15 [95%CI 0.08-0.27] for the PS 2-4 class), HER2 + disease (OR 1.78 [95%CI 1.27-2.48]), type of treatment (chemotherapy/targeted therapy/immunotherapy OR 5.01 [95%CI 3.13-8.18]), and period (OR 1.65 [95%CI 1.22-2.26] for 2012-2016, compared to 2008-2011). CONCLUSION: In this large database, few older MBC patients were enrolled in a trial compared with younger ones.

Myopathy with MTCYB mutation mimicking Multiple Acyl-CoA Dehydrogenase Deficiency.

We describe two patients with mitochondrial DNA mutations in the gene encoding cytochrome b (m.15579A>G, p.Tyr278Cys and m.15045G>A p.Arg100Gln), which presented as a pure myopathic form (exercise intolerance), with an onset in childhood. Diagnosis was delayed, because acylcarnitine profile showed an increase in medium and long-chain acylcarnitines, suggestive of multiple acyl-CoA dehydrogenase deficiency, riboflavin transporter deficiency or FAD metabolism disorder. Implication of cytochrome b in fatty acid oxidation, and physiopathology of the mutations are discussed.

Multiple acyl-CoA dehydrogenase deficiency (MADD) as a cause of late-onset treatable metabolic disease.

INTRODUCTION: Late-onset multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare, treatable, beta-oxidation disorder responsible for neuromuscular symptoms in adults. This case series describes the clinical and biochemical features of 13 French patients with late-onset MADD. METHODS AND RESULTS: Thirteen ambulant patients (eight women, five men), with a median age at onset of 27 years, initially experienced exercise intolerance (n=9), isolated muscle weakness (n=1) and a multisystemic pattern with either central nervous system or hepatic dysfunction (n=3). During the worsening period, moderate rhabdomyolysis (n=5), a pseudomyasthenic pattern (n=5) and acute respiratory failure (n=1) have been observed. Weakness typically affected the proximal limbs and axial muscles, and there was sometimes facial asymmetry (n=3). Moderate respiratory insufficiency was noted in one case. Median baseline creatine kinase was 190IU/L. Lactacidemia was sometimes moderately increased at rest (3/10) and after exercise (1/3). The acylcarnitine profile was characteristic, with increases in all chain-length acylcarnitine species. Electromyography revealed a myogenic pattern, while muscle biopsy showed lipidosis, sometimes with COX-negative fibers (n=2). The mitochondrial respiratory chain was impaired in five cases, with coenzyme Q10 decreased in two cases. All patients harbored mutations in the ETFDH gene (four homozygous, seven compound heterozygous, two single heterozygous), with nine previously unidentified mutations. All patients were good responders to medical treatment, but exercise intolerance and/or muscular weakness persisted in 11 of them. CONCLUSION: Late-onset forms of MADD may present as atypical beta-oxidation disorders. Acylcarnitine profiling and muscle biopsy remain the most decisive investigations for assessing the diagnosis. These tests should thus probably be performed more widely, particularly in unexplained cases of neuromuscular and multisystemic disorders.

Port catheter versus peripherally inserted central catheter for postoperative chemotherapy in early breast cancer: a retrospective analysis of 448 patients.

PURPOSE: We aimed to compare the complication rate between port catheters (PC) and peripherally inserted central catheters (PICC) for the administration of postoperative chemotherapy for breast cancer. METHODS: All patients treated from January 2010 to August 2012 at the Centre Henri Becquerel for early breast cancer requiring postoperative chemotherapy were retrospectively screened. The primary endpoint was the occurrence of a major complication related to the central venous catheter. Major complications were defined as any grade 3 event according to CTCAE 4.0, delay in chemotherapy >7 days, change of the device, life-threatening event, event requiring a hospitalization, or a prolongation of hospitalization. RESULTS: A total of 448 patients were included; 290 had a PC and 158 a PICC. Overall, 31 major complications related to the central venous catheter were observed: 13 for patients with a PC (4.5%) and 18 for patients with a PICC (11.4%). In univariate analysis, having a PICC was the only factor significantly associated with a higher risk of major complications (HR = 2.83, p = 0.0027). We observed a trend for a higher risk of major complications for patients older than 60 years or with BMI >25 (p = 0.06). In multivariate analysis, having a PICC was the only predictive factor of major complications (HR = 2.89, p = 0.004). CONCLUSIONS: In univariate and multivariate analysis, having a PICC instead of a PC was the only predictive factor of device-related major complication. If confirmed prospectively by the NCT02095743 ongoing trial, this result might modify the management of adjuvant chemotherapy administration.

[Nutritional management of patients with head and neck cancer treated with radiation]. / Prise en charge nutritionnelle des patients atteints de cancer de la tête et du cou traité par irradiation.

Radiotherapy and chemotherapy are standard treatment of head and neck cancer alone or associated to surgical treatment. Early (during treatment or the following weeks) and late side effects contribute to malnutrition in this population at risk. In this context, nutritional support adapted by dietary monitoring and enteral nutrition (nasogastric tube or gastrostomy) are often necessary. The early identification of the patients with high malnutrition risk and requiring enteral nutrition is necessary to improve the tolerance and efficacy of treatment.

Impact of geriatric risk factors on pegylated liposomal doxorubicin tolerance and efficacy in elderly metastatic breast cancer patients: final results of the DOGMES multicentre GINECO trial.

BACKGROUND: Metastatic breast cancer chemotherapy in the elderly is considered effective in carefully selected patients, but there is little data regarding its effect in vulnerable patients. METHODS: We evaluated tumour response (primary endpoint), feasibility and outcomes after six courses of an adapted dose of pegylated liposomal doxorubicin (PLD) (40 mg/m(2) every 28 days) as first-line chemotherapy for hormone-resistant MBC. RESULTS: Of 60 patients >70 years (median 77 years), 15% had performance status ≥2 and 73% had visceral metastases. Geriatric assessment included: ≥2 comorbidities, 42%; ≥1 deficiency in Activities of Daily Living (ADL), 10% and Instrumental ADL (IADL), 82%; living in residential homes, 12%; albumin <35 g/L, 17%; body mass index (BMI) <21, 20%; depression, 17%; and lymphocytes ≤1 × 10(3)/mm(3), 27%. Complete response, partial response and stable disease were observed in 5%, 15% and 60%, respectively, but only 48% completed six cycles. Treatment discontinuations were mostly due to disease progression (18%) and non-haematological (NH) toxicities (22%). Eight patients died during treatment (three possibly related to PLD), and 15 had unplanned hospital admissions. Exploratory analyses to identify geriatric covariates associated with treatment outcomes revealed severe haematological toxicities significantly correlated with lymphocytes ≤1 × 10(3)/mm(3). NH toxicities correlated with age ≥80 years and living in residential homes. Progression-free survival (median 6.1 months) decreased with age, deficiency in IADL, cardiac dysfunction and living in residential homes. Overall survival (median 15.7 months) also decreased with living in residential homes. CONCLUSION: Despite manageable haematological toxicities and expected response rates, PLD feasibility was poor in unselected elderly patients.

French version of the Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog) version 3.

PURPOSE: Impairment of cognitive function, a common complaint in patients receiving chemotherapy, is usually measured through neuropsychological tests. Patient self-evaluation of cognitive difficulties is an important complement to those tests. The Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog) is a self-report questionnaire with potential to be used in standard clinical practice as a tool for evaluating patient's cognitive function before, during, and after chemotherapy. The purpose of our study was to conduct linguistic validation of the French version of the FACT-Cog. METHODS: Both qualitative and quantitative methods were used in this study. After undergoing a rigorous translation methodology, the French FACT-Cog version was pretested in France with 35 cancer patients undergoing chemotherapy treatment. Interviews were conducted with all patients to ascertain their understanding of each item. The validation of the final version was conducted among 63 cancer patients, and sociodemographic information was collected as well as brief measure of cognitive function and depression score. RESULTS: Patient comments obtained through the cognitive debriefing interviews indicated that patients understand the French FACT-Cog items as they are intended and that the measure is culturally appropriate. Internal consistency reliability of the subscales, evaluated using Cronbach's coefficient alpha, was high for all four subscales: Perceived Cognitive Impairments = 0.93, Impact On QOL = 0.85, Comments From Others = 0.70, and Perceived Cognitive Abilities = 0.89. All item-total correlations for each subscale were greater than 0.20, and most were greater than 0.50. CONCLUSIONS: Results from this study effectively demonstrate that the French FACT-Cog is a reliable instrument for the self-reporting of cognitive abilities in patients undergoing chemotherapy.

Severe clinical toxicities are correlated with survival in patients with advanced renal cell carcinoma treated with sunitinib and sorafenib.

BACKGROUND: In advanced renal cell carcinoma (RCC), sunitinib and sorafenib tyrosine kinase inhibitors (TKI) are associated with several clinical side effects, with no definitive established data concerning their clinical impact. METHODS: From June 2006 to June 2008, main clinical TKI-induced toxicities, including digestive, cardiac, dermatologic and asthenia were retrospectively collected using the NCI-CTC version 3.0 in patients treated with TKI for an RCC. RESULTS: The median overall survival was significantly improved in patients with grade 3-4 clinical toxicities (36 vs 12 months, P=0.009). In multivariate analysis, the Memorial Sloan-Kettering Cancer Center risk groups (good vs intermediate or poor) and clinical toxicities (grade 3-4 vs 1-2) were identified as independent prognostic factors of better survival (P=0.002 and P=0.02, respectively). The Charlson comorbidity index score (>7 vs <7) was identified as independent predictive factor of severe clinical TKI-induced toxicities (P=0.02). CONCLUSION: In this unselected patients of RCC, clinical TKI-related severe toxicities were more frequent in patients with comorbidities and were associated with better survival.

Comprehensive cDNA study and quantitative analysis of mutant HADHA and HADHB transcripts in a French cohort of 52 patients with mitochondrial trifunctional protein deficiency.

BACKGROUND: Deficiency of mitochondrial trifunctional protein (MTP) is caused by mutations in the HADHA and HADHB genes, which have been mostly delineated at the genomic DNA level and have not been always elucidated. AIM: To identify mutations in a French cohort of 52 MTP deficient patients and the susceptibility of mutations generating premature termination codons (PTCs) to the nonsense mRNA mediated decay (NMD). METHODS: Mutation screening in fibroblasts was performed at the cDNA level and real-time RT-PCR was used to compare the levels of the different PTC-bearing mRNAs before and after a treatment of fibroblasts by emetine, a translation inhibitor. RESULTS: A mutation detection rate of 100% was achieved. A total of 22 novel mutations were identified, including a large-sized genomic deletion in HADHB gene. A high proportion of all identified mutations were non-sense, frameshift and splicing mutations, generating (PTCs), distributed essentially on HADHA coding regions. We could demonstrate that the majority of mutations resulting in PTCs conform to the established rules governing the susceptibility to NMD. CONCLUSION: Our results emphasize the value of cDNA analysis in the characterization of HADHA and HADHB mutations and further strengthen the model of haploinsufficiency as a major pathomechanism in MTP defects.

[Multiple acyl-CoA dehydrogenase deficiency (MADD): a curable cause of genetic muscular lipidosis]. / Déficit multiple en acyl-CoA déshydrogénases : une cause traitable de lipidose musculaire d'origine génétique.

INTRODUCTION: Multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare genetic disease involving fatty acid oxidation. It is due to the deficiency of one of the two electron transporters: electron transfer flavoprotein (ETF) or electron transfer flavoprotein ubiquinone oxydoreductase (ETF-QO). Symptoms begin more often in childhood or in young adulthood with a multisystemic disease with encephalopathy or muscular weakness. CASE REPORTS: We report here two adult cases with ETF-QO deficiency, confirmed by mutation analysis (ETFDH gene), revealed by a muscular weakness associated with muscle lipidosis. One of our patients presented an acute encephalopathy with vomiting ten years before the onset of muscular symptoms. The second patient exhibited a slowly progressive pelvic girdle muscle weakness. Diagnosis was established by characteristic abnormalities of acylcarnitine profile by tandem mass spectrometry. For both patients, a dramatic clinical improvement was observed under treatment with riboflavine and L-carnitine. CONCLUSION: Since it is a treatable disorder, this diagnosis must be considered by performing an acylcarnitine profile in all patients presenting with an unexplained muscular weakness.

[Pneumocystis pneumonia in two breast cancer patients treated with docetaxel: an unusual adverse event of chemotherapy]. / Deux observations de pneumocystose chez des patientes traitées par docétaxel pour un cancer du sein : une complication inhabituelle de la chimiothérapie.

We report two cases of pneumocystis pneumonia in patients receiving chemotherapy for breast cancer. These case series emphasize the frailty of the patients as the causative role for occurrence of this uncommon complication of chemotherapy in breast cancer. We remind the importance of screening for unusual adverse events in frail patients receiving chemotherapy.

Cardiofaciocutaneous (CFC) syndrome associated with muscular coenzyme Q10 deficiency.

The cardiofaciocutaneous (CFC) syndrome is characterized by congenital heart defect, developmental delay, peculiar facial appearance with bitemporal constriction, prominent forehead, downslanting palpebral fissures, curly sparse hair and abnormalities of the skin. CFC syndrome phenotypically overlaps with Noonan and Costello syndromes. Mutations of several genes (PTPN11, HRAS, KRAS, BRAF, MEK1 and MEK2), involved in the mitogen-activated protein kinase (MAPK) pathway, have been identified in CFC-Costello-Noonan patients. Coenzyme Q10 (CoQ10), a lipophilic molecule present in all cell membranes, functions as an electron carrier in the mitochondrial respiratory chain, where it transports electrons from complexes I and II to complex III. CoQ10 deficiency is a rare treatable mitochondrial disorder with various neurological (cerebellar ataxia, myopathy, epilepsy, mental retardation) and extraneurological (cardiomyopathy, nephropathy) signs that are responsive to CoQ10 supplementation. We report the case of a 4-year-old girl who presented a CFC syndrome, confirmed by the presence of a pathogenic R257Q BRAF gene mutation, together with a muscular CoQ10 deficiency. Her psychomotor development was severely impaired, hindered by muscular hypotonia and ataxia, both improving remarkably after CoQ10 treatment. This case suggests that there is a functional connection between the MAPK pathway and the mitochondria. This could be through the phosphorylation of a nuclear receptor essential for CoQ10 biosynthesis. Another hypothesis is that K-Ras, one of the proteins composing the MAPK pathway, might be recruited into the mitochondria to promote apoptosis. This case highlights that CoQ10 might contribute to the pathogenesis of CFC syndrome.

Methylmalonic and propionic acidaemias: management and outcome.

Organic acidurias comprise many various disorders. Methylmalonic aciduria (MMA) and propionic aciduria (PA) are the most frequent diseases and the two organic acidurias for which we have better knowledge of the long-term outcome. Comparing the outcome of patients born before and after 1990, it appears that better neonatal and long-term management have improved the survival rate. Less than 20% of the patients died in either the neonatal period or before the age of 10 years. However, most surviving patients showed poor nutritional status with growth retardation and about 40% present some kind of visceral or neurological impairment. The developmental outcome may have improved in MMA patients, with IQ higher than 75 in about 40% patients aged more than 4 years. Conversely, poor intellectual development is the rule in PA patterns, with 60% having an IQ less than 75 and requiring special education. Successful liver and/or renal transplantations, in a few patients, have resulted in better quality of life but have not necessarily prevented neurological and various visceral complications. These results emphasize the need for permanent metabolic follow-up whatever the therapeutic strategy.

In situ lipolytic regulation in subjects born small for gestational age.

OBJECTIVE: Subjects born small for gestational age (SGA) who are prone to develop insulin resistance in adulthood display an abnormal development pattern of the adipose tissue during fetal and postnatal life. Since the lipolytic activity of the adipose tissue is critical in the development of insulin resistance, the purpose of this study was to investigate whether SGA itself might affect lipolysis regulation. STUDY DESIGN: We studied the effect of catecholamines, by local injection of isoproterenol, and the effect of insulin, using two-step infusion at 8 and 40 mU/m2/min, on the in situ lipolysis of the subcutaneous abdominal adipose tissue of 23 subjects born SGA and 23 born appropriate for gestational age (AGA), using the microdialysis technique. RESULTS: Under isoproterenol infusion, the increase in dialysate glycerol concentration was significantly 1.5-fold higher in the SGA than in the AGA group (P=0.02) and induced a 20% increase in the plasma FFA concentration (P=0.04), whereas no significant increase was observed in the AGA group. The antilipolytic action of insulin on dialysate glycerol concentration was similar in both groups throughout the insulin infusion. CONCLUSION: Subjects born SGA demonstrated a hyperlipolytic reactivity to catecholamines, which might be regarded as an additional deleterious component of the insulin resistance associated with SGA. In contrast, being born SGA does not directly affect the antilipolytic action of insulin, showing that it does not play a major role in causing the long-term metabolic complications associated with reduced fetal growth.

Progression despite replacement of a myopathic form of coenzyme Q10 defect.

The authors report 7 years of follow-up evaluation of a patient with coenzyme Q10 (CoQ10) deficiency. Initial symptoms of exercise intolerance and hyperlactatemia improved markedly with substitutive treatment. However, CoQ(10) supplementation did not prevent the onset of a cerebellar syndrome. A switch to idebenone treatment resulted in clinical and metabolic worsening, which disappeared with subsequent CoQ10 treatment. CoQ10 defects may cause progressive neurologic disease despite supplementation.

Anti-Müllerian hormone levels in serum from human foetuses and children: pattern and clinical interest.

Serum anti-Müllerian hormone (AMH) determination has been used to investigate gonadal development and abnormal sexual differentiation, but until recently, it was based on assays developed by specialized laboratories. A short time ago, a sensitive assay kit was developed commercially (Immunotech-Beckman Coulter) for clinical use. With this method, we established usual levels of serum AMH in fetuses, newborns, and pre-pubertal children, and evaluated the clinical value of this assay. AMH measurement required only 25 microl of sample and could be performed within 3 h. In females, AMH emerged after birth at low levels (median: 4 ng/ml). In males, AMH levels remained stable during fetal life (median: 44.4 ng/ml), peaked in the first months of life to reach a median of 124.7 ng/ml, then fell with wide individual variations. Cord blood AMH levels at birth may be useful to investigate ambiguous genitalia suspected prenatally. In children with isolated microphallus or hypospadias, decreased AMH values are in favor of testis dysfunction. When testes cannot be palpated, a single determination of serum AMH levels can distinguish between anorchia and cryptorchidism.

Exploration of glucose homeostasis during fasting in growth hormone-deficient children.

In order to define more precisely the risk of hypoglycaemia in GH-deficient children and to clarify the role of growth hormone (GH) in glucose homeostasis, a 24-h fast was monitored in 10 GH-deficient children aged 1.1-6.5 y. Asymptomatic hypoglycaemia (blood glucose < or = 2.6 mmol/l) occurred in 9/10 children, 2 of whom prematurely interrupted the test. Blood glucose profile was not reproducible between children and had no correlation with age (p = 0.48). Gluconeogenesis was considered as non-altered as read from the normal plasma lactate and pyruvate concentrations throughout the test. Plasma ketone body concentrations increased during the test, but were lower than expected with respect to the decrease of blood glucose. This suggests insufficient ketogenesis which could exacerbate hypoglycaemia in GH-deficient children if brain glucose utilization were not alleviated by ketone body oxidization, as is normally the case. The positive glucose response after glucagon stimulation in 6/10 patients indicated normal hepatic glycogen content. However, these responses were unexpected following the prolonged fast and its concomitant hypoglycaemia, and would therefore tend to suggest a defect in glycogenolysis. These results confirm the tendency to hypoglycaemia, even after infancy, in GH-deficient children. These hypoglycaemias may occur by different types of malfunctioning, such as insufficient ketogenesis or a defect in glycogenolysis. These hypotheses require confirmation by a more systematic study of the metabolic and hormonal changes that occur during fasting in both GH-deficient and normal children.

In vivo functional investigations of lactic acid in patients with respiratory chain disorders.

OBJECTIVE: To assess the prevalence of in vivo detectable abnormalities of lactate metabolism in mitochondrial disorders. DESIGN: Retrospective study in a metabolic investigation unit. PATIENTS: 28 patients with a respiratory chain disorder identified from biochemical or genetic analyses, or both, and 133 age matched controls. Controls were children in whom causes of secondary hyperlactataemia and/or disorders, affecting the energy pathways could be excluded. METHODS: Lactate and pyruvate were measured in blood, together with other intermediary metabolism indices, before and one hour after four meals each day. Lactate and creatinine in a 24 hour urine sample collected at the same time were analysed. When basal hyperlactataemia was not evident, an intravenous glucose or pyruvate loading test was performed as a provocative test. RESULTS: Abnormal lactate metabolism was found in 25 of 28 patients thus demonstrating the potential usefulness of these investigations in the diagnosis of mitochondrial disease. Moderate lactate accumulation was present in relatively mild disease, associated with a mitochondrial DNA mutation and combined respiratory complexes deficiency. By contrast, high lactate concentrations were observed in very young children, with severe disease, isolated complex deficiency, and no apparent mitochondrial DNA defect.

A point mutation in the glycerol kinase gene associated with a deletion in the dystrophin gene in a familial X-linked muscular dystrophy: non-contiguous gene syndrome involving Becker muscular dystrophy and glycerol kinase loci.

We report a family with an X-linked recessive muscular dystrophy characterised by exercise-induced myalgia, recurrent pigmenturia and mild proximal muscle involvement. Immunocytochemical and immunoblotting analysis in muscle, using the antibody directed against the rod domain of dystrophin, revealed a loss of immunoreactivity, but the immunolabelling using the antibodies directed against the COOH and NH2 domains of dystrophin were almost normal. The immunoreactions for alpha-sarcoglycan, gamma-sarcoglycan and beta-dystroglycan were normal. In the five male patients of this family with increased serum creatine kinase levels (from x8 to x50), mass spectrometry screening of the urine revealed a large increase in glycerol elimination which was quantified by enzymatic assay (from x14 to x39). An in-frame deletion of the dystrophin gene (exons 13-29) was found in the same five males and in three carrier females. All the deleted chromosomes also carried a missense mutation at nucleotide 947 of the Xp glycerol kinase (GK) gene resulting in a Thr to Met substitution at codon 278. These findings indicate that the two mutations cosegregate on the same chromosome in this family. This is the first reported case of two physically independent mutations, within the DMD and GK genes, which are contiguous but several hundred kilobases apart.