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Purpose of review Treatment options for mitochondrial myopathies remain limited despite rapid advances in the understanding of the molecular basis of these conditions. Existing therapies continue to be evaluated and novel treatment strategies are starting to appear on the horizon. Recent findings Exercise training continues to show promise as a method of improving exercise tolerance and enhancing oxidative capacity. Coenzyme Q10 deficiency appears to be a relatively common finding in mitochondrial disorders and is likely to benefit from exogenous supplementation. Large-scale randomized clinical trials to evaluate these treatment options are now underway and this represents one of the most important developments in recent years. Activation of the peroxisome proliferator-activated receptor/peroxisome proliferator-activated receptor-gamma coactivator-1alpha pathway has been shown to induce mitochondrial biogenesis leading to a delayed onset of myopathy and prolonged lifespan in mouse models. A ketogenic diet has also been found to induce mitochondrial biogenesis in mice with mitochondrial myopathy. Summary Therapeutic trials of exercise training and coenzyme Q10 supplementation should continue to be offered to patients with mitochondrial myopathies pending the results of evaluation in randomized clinical trials. Further investigation of peroxisome proliferator-activated receptor/peroxisome proliferator-activated receptor-gamma coactivator-1alpha pathway activation, ketogenic diets and other new strategies is required.

259 Background: Androgen deprivation therapy has been the standard of care for advanced prostate cancer for many years. However recent studies have reported a survival benefit for upfront docetaxel chemotherapy in men with hormone sensitive prostate cancer. The GenTax trial was a single institution phase II study investigating clinical outcome and gene profiling for patients with treatment naïve prostate cancer treated with either docetaxel chemotherapy plus androgen deprivation therapy (D+ADT) or androgen deprivation therapy alone (ADT). We report on updated clinical outcome data for this trial. Methods: Patients with newly diagnosed T3/T4, PSA ≥ 50ng/ml or Gleason score ≥ 8, or metastatic disease were enrolled. Patients were randomised to ADT or D+ADT (docetaxel 75mg/m2 q21 days for 6 cycles). Data were analysed for overall survival, toxicities, time to second line treatment and number of subsequent treatments. Results: 30 patients were randomly assigned to ADT (n = 15) or D+ADT (n = 15) between 10/13/2005 and 12/02/2009. 7 patients in each arm had metastatic disease. Grade 3-4 toxicities were infrequent in D+ADT arm and were not noted in the ADT arm. There were no significant differences between treatment arms for overall survival (log rank p = 0.977) or time to second line treatment (log rank p = 0.954). Median overall survival was 98 months (95% CI 72.3 - 123.7) for ADT and 87 months (95% CI 71.5 - 102.5) for D+ADT. Median time to second line treatment was 45 months (95% CI 13.4 - 76.6) for ADT and 46 months (95% CI 13.2 – 78.8) for D+ADT. Number of subsequent treatments ranged from 0-6 (mean 2.40) for ADT-only and 0-5 (mean 2.13) for D+ADT. Conclusions: The combination of docetaxel and ADT in the hormone sensitive setting is well tolerated, as previously reported. This study was not sufficiently powered to detect statistically significant differences in survival. Patients proceeded to receive a number of subsequent lines of therapy although the order in which these were given was variable. There is a need to establish optimal sequencing of treatments in the upfront docetaxel era. Clinical trial information: 2004-004874-96.

Optimal margins for wide local excision (WLE) have not been clearly established. Larger margins lead to lower recurrence rates but at the expense of cosmetic appearance. NICE guidelines recommend a 2 mm margin for ductal carcinoma in-situ (DCIS), whilst the British Association of Surgical Oncology (BASO) recommend units develop local guidelines. There are presently no specific guidelines for invasive cancer. We surveyed members of the Association of Breast Surgeons (ABS) in order to establish current practice nationally. We hypothesised that larger units may accept narrower excision margins to the benefit of better cosmesis.A postal questionnaire was sent to all ABS members in October 2010. This consisted of questions about the current practice of the surgeon and their unit. 481 questionnaires were posted in total, all questionnaires returned by April 2011 were analysed.Questionnaire response rate was 60% (281). Surgeons operating on over 50 cancers per year accepted smaller margins than those operating on less than 50 (p0.02). Acceptable adequate anterior and radial margins ranged from 0 to 10 mm for DCIS and 0 to 5 mm for invasive cancer. A variety of approaches to re-excising anterior margins were reported.This survey suggests that substantial variations exist in current practice with regard to the approach to WLE. Operator workload appears to influence what is deemed to be an acceptable margin. There is a need for standardised national and international guidelines.

Background Spinocerebellar ataxia syndromes presenting in adulthood have a broad range of causes, and despite extensive investigation remain undiagnosed in up to ∼50% cases. Mutations in the mitochondrially encoded MTATP6 gene typically cause infantile-onset Leigh syndrome and, occasionally, have onset later in childhood. The authors report two families with onset of ataxia in adulthood (with pyramidal dysfunction and/or peripheral neuropathy variably present), who are clinically indistinguishable from other spinocerebellar ataxia patients. Methods Genetic screening study of the MTATP6 gene in 64 pedigrees with unexplained ataxia, and case series of two families who had MTATP6 mutations. Results Three pedigrees had mutations in MTATP6 , two of which have not been reported previously and are detailed in this report. These families had the m.9185T>C and m.9035T>C mutations, respectively, which have not previously been associated with adult-onset cerebellar syndromes. Other investigations including muscle biopsy and respiratory chain enzyme activity were non-specific or normal. Conclusions MTATP6 sequencing should be considered in the workup of undiagnosed ataxia, even if other investigations do not suggest a mitochondrial DNA disorder.

Inherited ataxias are heterogeneous disorders affecting both children and adults. The primary cause can be identified in about half of the patients and only very few can receive causative therapy.The authors performed sequencing of known Coenzyme Q10 (CoQ10) deficiency genes in 22 patients with unexplained recessive or sporadic ataxia.CABC1/ADCK3 mutations were detected in four patients and two siblings presenting with cerebellar ataxia, epilepsy and muscle symptoms. Spasticity, dystonia, tremor and migraine were variably present; cognitive impairment was severe in early childhood cases, but was absent in adults. In contrast to previous reports, two of the patients had a later-onset, very mild phenotype and remained ambulatory in their late forties. Muscle biopsy revealed lipid accumulation, mitochondrial proliferation and cytochrome c oxidase-deficient fibres, but no typical ragged red fibres. Respiratory-chain enzyme activities and CoQ10 were decreased in severely affected patients but remained normal in a mildly affected patient at 46 years of age.These observations highlight the importance of screening for a potentially treatable cause, CABC1/ADCK3 mutations, not only in severe childhood-onset ataxia, but also in patients with mild cerebellar ataxia in adult life.

Inherited ataxias are heterogeneous disorders affecting both children and adults. The primary cause can be identified in about half of the children and the hit rate is even lower in adults. In 22 patients with unexplained recessive or sporadic ataxia sequencing of known coenzyme Q10 (CoQ10) deficiency genes detected CABC1/ADCK3 mutations in six patients (four families), who presented with cerebellar ataxa, epilepsy, spasticity and muscle symptoms. Two patients had a later onset (15 and 27 years) with mild disease. It is extremely important to screen for CABC1/ADCK3 mutations in ataxia, because is potentially treatable and it can present in adult life.