Comparison between MRI and choline-PET trans-perineal target biopsies and saturation biopsies for detection and topography of intra-prostatic recurrence after primary radiation therapy for prostate cancer.

INTRODUCTION: Biochemical recurrence of prostate cancer after radiation therapy occurs in 5 to 50% of cases depending on the radiation technique used. The diagnosis of recurrence of prostate adenocarcinoma must be made accurately. The aim of this study was to compare transperineal saturation and target biopsies to index lesion (IL) as defined on MRI and 18FCholine PET-CT (PETc) for detection of intra-prostatic recurrence after primary radiation therapy for prostate cancer. MATERIALS AND METHODS: Thirty-eight patients with an history of prostate radiation for prostate cancer and biochemical recurrence were retrospectively included between March 2013 and June 2017. All patients had PETc and multiparametric MRI (MRI) defining IL. All patients had transperineal saturation biopsies and target biopsies the IL. RESULTS: Among 38 patients with biochemical recurrence, 33 (87%) had biopsy proven recurrence in the prostate. The sensitivity and specificity of MRI were 32% (SD:19%) and 91% respectively (SD:7%). The sensitivity and specificity of PETc were 33% (SD:22%) and 78% respectively (SD:12%). Saturation trans-perineal and target biopsies allowed detection of disease recurrence in 79% and 84% of patients, respectively. CONCLUSION: In case of positive imaging, both trans-perineal prostate saturation and target biopsies offer good performance to confirm intraprostatic recurrence. However, MRI and PETc low sensitivity to detect all sites of local recurrence of prostate cancer after radiation still justify the completion of systematic saturation biopsies. LEVEL OF EVIDENCE: 3.

R-CHOP appears to be the best first-line treatment for second primary diffuse large B cell lymphoma: a cancer registry study.

Second primary diffuse large B cell lymphoma (spDLBCL) is defined as a metachronous tumor occurring after a first primary cancer. To date, while R-CHOP is the standard first-line treatment for de novo DLBCL, no available data show that R-CHOP is the optimal treatment for spDLBCL. This exploratory study aimed to investigate treatment of spDLBCL. From 2008 to 2015, the Poitou-Charentes general cancer registry recorded 68 cases of spDLBCL ≤ 80 years old, having received a first-line treatment with either R-CHOP (78%) or other regimens (22%). Patients without R-CHOP have worse overall survival in univariate (HR 2.89 [1.33-6.24], P = 0.007) and multivariate (HR 2.98 [1.34-6.67], P = 0.008) analyses. Patients without R-CHOP more frequently had PS > 1 (67% vs. 28%, P = 0.007) and prior chemotherapy (60% vs. 26%, P = 0.02), which suggests that both of these factors influence a clinician's decision to not use R-CHOP. Prior chemotherapy had no prognostic impact in univariate and multivariate analyses; this result could call into question the risk-benefit balance of not using R-CHOP to prevent toxicity. In our study, one DLBCL out of ten occurred after a first primary cancer, and as regards de novo DLBCL, R-CHOP appeared to be the best first-line treatment. Larger series are needed to confirm these results.

Glioma-grade diagnosis using in-phase and out-of-phase T1-weighted magnetic resonance imaging: A prospective study.

PURPOSE: The purpose of this prospective study was to determine whether chemical shift gradient-echo magnetic resonance imaging (MRI) could predict glioma grade. MATERIALS AND METHODS: A total of 69 patients with 69 gliomas were prospectively included. There were 41 men and 28 women with a mean age of 50±(SD) years (range: 16-82years). All patients had MRI of the brain including chemical shift gradient-echo sequence, further referred to as in- and out-of phase sequence (IP/OP). Intravoxel fat content was estimated by signal loss ratio (SLR=[IP-OP]/2IP), between in- and out-of-phase images, using a region of interest placed on the viable portion of the gliomas. Association between SLR and glioma grade was searched for using Wilcoxon and Mann-Whitney U tests and diagnostic capabilities using area under the receiver operating characteristic (AUROC) curves. RESULTS: A significant association was found between SLR value and glioma grade (P<0.0001). SLR>9‰ allowed complete discrimination between grade III and grade II glioma with 100% specificity (95% CI: 85-100%), 100% sensitivity (95% CI: 78-100%) and 100% accuracy (95% CI: 90-100%) (AUROC=1). A SLR>20‰ allowed discriminating between grade IV and grade III glioma with 75% specificity (95% CI: 57-89%), 73% sensitivity (95% CI: 45-92%) and 72% accuracy (95% CI: 57-84%) (AUC=0.825, 95% CI: 0.702-0.948). The AUROC for the diagnosis of high-grade glioma (grade III and IV vs. grade II) was 1. CONCLUSION: Chemical shift gradient echo MRI provides accurate grading of gliomas. This simple method should be used as a biomarker to predict glioma grade.

Intra peritoneal abdominal fat area measured from computed tomography is an independent factor of severe acute pancreatitis.

PURPOSE: The purpose of this study was to search for a possible relationship between acute pancreatitis (AP) severity and visceral fat (VF) surface on contrast-enhanced computed tomography (CECT). MATERIAL AND METHOD: A total of 112 patients with AP who underwent CECT within 2 to 3 days after the beginning of AP were included. There were 68 mean and 44 women, with a mean age of 56.3±21.6 (SD) years (range: 19-98 years). AP was regarded as mild for patients with an hospital stay up to 5 days and severe for those with an hospital stay greater than 5 days. VF surface was measured on CECT at the level of L4-L5 and of the umbilicus. Association between AP severity and VF surface, computed tomography severity index (CTSI), modified CTSI (mCTSI) and other variables were searched for using uni- and multivariate analysis. RESULTS: At univariate analysis, the VF surface at the level of L4 was greater in patients with severe AP (129.3±68.6 [SD] cm2; range: 21.8-355.8 cm2) than in patients with mild AP (100.1±68.4 [SD] cm2; range:13.2-333 cm2) (P=0.006). Similarly, the VF surface at the umbilicus was greater in patients with severe AP (161.1±76.1 [SD] cm2; range: 31.3-376.7cm2) than in those with mild AP (128.4±74.3cm2; range: 12.8-323.1cm2) (P=0.024). CTSI and mCTSI were also associated to AP severity. At multivariate analysis, only VF surface either measured at the umbilical or at the L4-L5 level was associated with AP severity (P=0.017 and 0.006, respectively). CONCLUSION: VF surface at the level of L4-L5 on CECT is an independent factor of AP severity. VF surface at the level of L4-L5 on CECT is an independent factor of AP severity. These results are in line with recent data on the role of abdominal fat in the genesis of inflammatory response, which is associated with severe forms of AP.

Treatment compliance with European guidelines and prognosis of Clostridium difficile infection according to age.

OBJECTIVE: Age>65 years is associated with the recurrence and poor prognosis of Clostridium difficile infection (CDI). Data on elderly patients (≥75 years) is scarce, and little is known about compliance with European guidelines in terms of specific treatment. We aimed to analyze the treatment and prognosis of CDI in two groups of patients aged

Chart for renal tumor microwave ablation from human study.

PURPOSE: To define microwave ablation (MWA) charts according to time and power in human renal tumors and to compare them to the charts given by the HS AMICA manufacturer. MATERIALS AND METHODS: A total of 54 patients with 54 renal cancers who underwent MWA were included. There were 36 men and 18 women with a mean age of 72.5±10[SD] years (range: 40-91years). The system used for MWA was HS AMICA with the Amica-probe V4 applicator. The following variables (antero-posterior diameter, transverse diameter, cranio-caudal diameter and volume were measured on computed tomography examinations performed one month after MWA. The dimensions of the ablation zone were correlated with power (40 or 60W) and exposure time (5, 10 and 15min) used for MWA. Actual ablation dimensions were compared to the manufacturer's data. RESULTS: The variation of diameters, with a longer ablation time, was linear at 40W with a volume increase of 30% for each additional 5minutes. At 60W, a more pronounced variation (volume increase of 112%) was observed. Compared to the manufacturer's chart, significantly larger ablation zones were obtained (P<0.05), the differences being mainly marked for the antero-posterior diameter (≥1cm). CONCLUSION: MWA using AMICA generator produces reproducible ablation area for given time and power in renal tumor ablation. The charts presented here should be used instead of the manufacturer's chart, which is based on porcine liver and is significantly different.

Left atrial volume assessed by ECG-gated computed tomography: Variations according to age, gender and time during the cardiac cycle.

PURPOSE: The purpose of this study was to retrospectively assess the accuracy of the maximal left atrial volume (LAVmax) measured at 75% of the cardiac cycle compared to the 40% measurements and to evaluate this volume according to age and gender. PATIENTS AND METHOD: A total of 150 patients with a mean age of 50±17 (SD) years (range: 21-79 years) were analyzed. There were 78 men and 72 women. LAVmax were measured from retrospective triphasic cardiac-gated multi-detector computed tomography (MDCT) data at the 40% (LAV40) and 75% (LAV75) of the RR cycle phases by a semi-automatic method. RESULTS: LAV40was 50.7±14mL/m2 and LAV75 was 42.5±13mL/m2. The difference was statistically significant. Considering the reference range of LAVmax reported in the literature, 33% of the patients had enlarged LA with LAV40 and only 17% with LAV75. These volumes were positively influenced by age but not by gender. The relationship between LAV75 and LAV40 was: LAV75=0.908 LAV40-3.486 (r2=0.92) or LAV40=1.1×LAV75+3.8 (r2=0.92). CONCLUSION: LAVmax measured at the 75% of the cardiac cycle phase significantly underestimates actual LAV leading to reconsider normal values. LAV40 can be computed from the measured value of LAV75 obtained on prospective ECG-gated MDCT.

Prognostic factors for parotid metastasis of cutaneous squamous cell carcinoma of the head and neck.

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) develops on the head in 80% of cases. Parotid metastasis (PM) is rare, but treatment, which associates surgery and radiation therapy, is heavy and prognosis poor. MATERIAL AND METHODS: All cases of parotidectomy for PM of CSCC of the head and neck between 2005 and 2015 were studied retrospectively. Epidemiologic, oncologic and therapeutic data were analyzed. Overall and specific survival were calculated following Kaplan-Meier. Log-rank and Cox models were used to identify prognostic factors for PM. OBJECTIVES: The principal study objective was to identify factors for survival in PM from CSCC of the head and neck. RESULTS: Thirty-five patients were included. Mean time to onset of PM was 13months. Overall 1-, 2- and 5-year survival was respectively 70, 66 and 59%. Independent prognostic factors comprised immunodepression, age at treatment, positive CSCC margins, macroscopic facial nerve involvement, and metastatic cervical adenopathies. CONCLUSION: The study confirmed an association of several independent prognostic factors at the stage of parotid lymph-node metastasis, related to patient, primary CSCC and PM. Complete primary resection is essential to reduce the risk of PM. Intensified radiologic and clinical surveillance should enable early diagnosis.

Percutaneous microwave ablation of renal cancers under CT guidance: safety and efficacy with a 2-year follow-up.

AIM: To evaluate the safety and efficiency of percutaneous microwave ablation (MWA) of renal cell carcinomas (RCC) carried out under computed tomography (CT) guidance. MATERIALS AND METHODS: A retrospective study was performed on RCC that was either histologically proven or diagnosed at imaging (Bosniak IV cyst) and treated by MWA under general anaesthesia with CT guidance. Indications for percutaneous ablation were based on the American Urological Association recommendations. Twenty-four months post-procedure follow-up was performed. RESULTS: Sixty-two patients presenting one or more RCC (84 tumours ranging from 10-48 mm in diameter; mean diameter: 25.6 mm) were included. Technical success was achieved for 78 tumours (58 patients). For four patients, the treatment was stopped due to gas dissection failure. At 3 months, six residual tumours were observed (8%). At 6 months, two recurrences and one residual tumour (3.8%) were observed; all were retreated with complete success. At 12 months, local control of the disease was achieved in 94% of cases (100% in cases where treatment was performed). Two cases of distal metastasis were observed after 12 and 24 months. At 24 months, one patient presented with a contralateral tumour. The complication rate was 4.8% including one grade III complication and two grade II complications according to the Clavien-Dindo classification. At 2 years, the cumulative disease-free survival rate and overall survival were 95% and 97%, respectively. CONCLUSION: MWA ablation under CT guidance to treat RCC is safe and provides a high rate of effectiveness at 24 months.

Relationships between macular pigment optical density and lacquer cracks in high myopia.

PURPOSE: A low concentration of macular carotenoid pigment (lutein and zeaxanthin) is a significant risk factor for macular degeneration. The goal of this paper is to investigate the relationship between macular pigment optical density (MPOD) and lacquer cracks (LC) in high myopia. METHODS: This is a prospective comparative observational study (NCT02205632) including high myopic patients with or without LC. High myopia was defined as a refractive error greater than 6 diopters of myopia or axial length greater than 26mm. All patients underwent best-corrected visual acuity in logMAR, MPOD measurement, multicolor imaging, SD-OCT, autofluorescence and axial length measurement. MPOD was calculated using heterochromatic flicker photometry. Group 1 was defined as eyes without LC and group 2 as eyes with LC. RESULTS: Forty-five eyes of 32 patients with a mean age of 51.3 years were included in group 1, and 15 eyes of 13 patients aged 54.1 in group 2 (P=0.56). Mean spherical equivalent was -10.11 diopters in group 1 and -15.11 in group 2 (P=0.0004). Mean visual acuity was +0.08 logMAR (0.8 in decimal notation) in group 1 and +0.11 logMAR (0.8 in decimal notation) in group 2 (P=0.061). Axial length was 27.8mm in group 1 and 29.2 in group 2 (P=0.0052). Central macular thickness was lower in group 1 (295µm) than in group 2 (305µm) (P<0.0001), and macular choroidal thickness did not differ between the two groups (P=0.094). Mean MPOD in group 2 was 0.52 and 0.63 in group 1 (P=0.042). Differences in axial length were not related to MPOD measurements (P=0.74). CONCLUSION: A lower rate of MPOD was observed in cases of LC in high myopia. Further studies are needed to investigate if dietary carotenoids could have a protective effect in reducing the risk of LC.

Preoperative detection of hepatic metastases from colorectal cancer: Prospective comparison of contrast-enhanced ultrasound and multidetector-row computed tomography (MDCT).

PURPOSE: The goal of this study was to prospectively compare the sensitivity of contrast-enhanced ultrasound (CEUS) with that of multiphase multidetector-row computed tomography (MDCT) in the preoperative detection of hepatic metastases. MATERIALS AND METHOD: Forty-eight patients, with a mean age of 62years old (range: 43-85years) were prospectively included. All patients underwent CEUS following intravenous administration of 2.4mL of an ultrasound contrast agent (Sonovue(®), Bracco, Milan, Italy) and multiphase MDCT. Intraoperative ultrasound examination (IOUS) was used as the standard of reference. RESULTS: A total of 158 liver metastases were identified by IOUS, 127 by preoperative MDCT (sensitivity; 80.4%) and 102 by CEUS (sensitivity, 64.5%). The 15.9% difference in sensitivity between CEUS and MDCT was statistically significant (P=0.002). There was a disagreement between IOUS and CEUS in 23 patients (47%) and in 13 patients (27%) between IOUS and MDCT. MDCT identified one or more additional metastases in 10 patients (20%) resulting in a change in the surgical strategy. CONCLUSION: Based on an unselected patient cohort and using multiphase MDCT, CEUS is significantly inferior to MDCT for the preoperative detection of hepatic metastases of colorectal cancer.

Prevalence of macular complications associated with high myopia by multimodal imaging.

PURPOSE: To describe the prevalence of macular complications in patients with visual acuity decrease related to high myopia (HM). To establish correlations between these complications and demographic or anatomical characteristics. MATERIALS AND METHODS: Cross-sectional observational study including HM patients undergoing best-corrected visual acuity (BCVA), fundus examination, macular SD-OCT, and fluorescein angiography in the case of suspicion of choroidal neovascularization (CNV). The presence of anatomical criteria (staphyloma, subfoveal choroidal thickness [CT]) and macular complications (CNV, lacquer cracks, central chorioretinal atrophy, dome-shaped macula with serous retinal detachment [SRD], retinal foveoschisis, macular hole and epiretinal membrane) was investigated. RESULTS: A total of 87 eyes of 47 patients were included (39 eyes without macular complication and 48 eyes with macular complications). In the case of macular complications, decrease in BCVA was related to CNV in 33%, macular hole in 25%, chorioretinal atrophy in 19%, foveoschisis in 11%, lacquer crack in 6%, to a dome-shape macula with serous retinal detachment in 4% and epiretinal membrane in 2%. After adjusting for interocular correlation and degree of myopia, staphyloma (P=0.0023), choroidal thinning (P=0.0036), and extrafoveal chorioretinal atrophy (P=0.042) were significantly associated with macular complications. CONCLUSIONS: High myopic patients with staphyloma or choroidal thinning should undergo regular comprehensive retinal screening for retinal complications.

Multiple myeloma: the quality of care is linked to geographical and organisational determinants. A study in a French registry.

Multiple myeloma is a haematological malignancy whose care is spread over several specialities and provided by centres that various sizes, which raises the issue of equal opportunities in care access. Incident cases of myeloma between 2008 and 2010 were exhaustively identified by the Poitou-Charentes Cancer Registry. To ascertain the quality of care, the diagnosis, staging, and treatment administered were compared to international recommendations. Three hundred and sixty-seven patients were included. The diagnostic procedure exhibited 98% compliance, the staging 58%, and treatment 89%. Concerning diagnostic and staging, non-compliance with recommendations was associated to the failure to perform collegiate case assessments in multidisciplinary team (MDT) meetings [OR 2.15 (1.15-4.04)], care provided at a secondary centre, and a distance between home and the centre of 5-25 km [2.16 (1.06-4.40)] and 25-50 km [2.86 (1.37-6.01)]. Regarding treatment, non-compliance with recommendations was associated with care provided at a secondary centre [5.28 (2.03-13.75)]. Finally, diagnosis, staging and treatment quality improved over time. This study underlines the need to improve the organisation of the healthcare offer, so that patients can receive the best possible care. MDT seems to be the main means to improve quality of care.

Vaccination coverage in French 17-year-old young adults: an assessment of mandatory and recommended vaccination statuses.

We aimed to assess vaccination coverage (VC) in 17-year-old French young adults (YAs) participating in one mandatory Day of Defence and Citizenship (DDC). Between June 2010 and May 2011, YAs participating in 43 randomly selected mandatory sessions of the DDC programme in Poitou-Charentes (France) were asked to provide their personal vaccination record. Tetanus, diphtheria, polio, hepatitis B, Haemophilus influenzae b, pertussis, measles, mumps and rubella vaccination status were assessed at ages 2, 6, 13 and 17 years. Of 2610 participants, 2111 (81%) supplied documents for evaluation. Of these, 1838 (87%, M:F sex ratio 0·96) were aged 17 years (9% of the global population of this age in the area). The assessment of the 17-year-olds demonstrated the following rates of complete vaccination: diphtheria-tetanus-polio 83%; measles, mumps and rubella 83%; pertussis 69%; H. influenzae b 61%; human papillomavirus 47%; and hepatitis B 40%. At age 6 years, only 46% had received two doses of the vaccine against measles. The YAs were not aware of their status but were in favour of vaccination. VC in YAs is insufficient, particularly for hepatitis B, pertussis and measles. Combined vaccines and the simplification of vaccination schedules should improve VC. Preventive messages should focus on YAs.

Surveillance of waiting times for access to treatment: a registry-based computed approach in breast cancer care.

The current study set out to automatically generate waiting times for access to surgery, chemotherapy and radiotherapy, and to analyse their determinants for non-metastatic breast cancer patients. We used data from the Poitou-Charentes regional cancer registry of women diagnosed with stages I-III breast carcinoma between 2008 and 2010. Waiting times were automatically computed from a previously validated algorithm modelling the care trajectory and then compared with national guidelines. The population of this study included 1082 patients. The compliance with guidelines ranged from 52.4% (access to adjuvant chemotherapy) to 89.2% (access to adjuvant radiotherapy). Younger age, a higher TNM stage, a lower grade, having a triple negative tumour, being the subject of multidisciplinary meetings and being a patient at a public hospital were associated with longer waiting times. The main result was the significant heterogeneity between geographical areas of treatment for all waiting times studied. The original, reproducible use of a registry-based automated algorithm to generate waiting times will help to follow these indicators routinely and efficiently.

Multicolumn spinal cord stimulation for significant low back pain in failed back surgery syndrome: design of a national, multicentre, randomized, controlled health economics trial (ESTIMET Study).

BACKGROUND: Many studies have demonstrated the efficacy of spinal cord stimulation (SCS) for chronic neuropathic radicular pain over recent decades, but despite global favourable outcomes in failed back surgery syndrome (FBSS) with leg pain, the back pain component remains poorly controlled by neurostimulation. Technological and scientific progress has led to the development of new SCS leads, comprising a multicolumn design and a greater number of contacts. The efficacy of multicolumn SCS lead configurations for the treatment of the back pain component of FBSS has recently been suggested by pilot studies. However, a randomized controlled trial must be conducted to confirm the efficacy of new generation multicolumn SCS. Évaluation médico-économique de la STImulation MEdullaire mulTi-colonnes (ESTIMET) is a multicentre, randomized study designed to compare the clinical efficacy and health economics aspects of mono- vs. multicolumn SCS lead programming in FBSS patients with radicular pain and significant back pain. MATERIALS AND METHODS: FBSS patients with a radicular pain VAS score≥50mm, associated with a significant back pain component were recruited in 14 centres in France and implanted with multicolumn SCS. Before the lead implantation procedure, they were 1:1 randomized to monocolumn SCS (group 1) or multicolumn SCS (group 2). Programming was performed using only one column for group 1 and full use of the 3 columns for group 2. Outcome assessment was performed at baseline (pre-implantation), and 1, 3, 6 and 12months post-implantation. The primary outcome measure was a reduction of the severity of low back pain (bVAS reduction≥50%) at the 6-month visit. Additional outcome measures were changes in global pain, leg pain, paraesthesia coverage mapping, functional capacities, quality of life, neuropsychological aspects, patient satisfaction and healthcare resource consumption. TRIAL STATUS: Trial recruitment started in May 2012. As of September 2013, all 14 study centres have been initiated and 112/115 patients have been enrolled. Preliminary results are expected to be published in 2015. TRIAL REGISTRATION: Clinical trial registration information-URL: www.clinicaltrials.gov. Unique identifier NCT01628237.

A prospective study evaluating sleep quality in Failed Back Surgery Syndrome patients treated by multicolumn spinal cord stimulation: study design protocol and presentation of the study population.

BACKGROUND AND PURPOSE: One of the main consequences of chronic pain syndrome is major impairment of the quality of sleep. Chronic pain and insomnia are independently linked to significant reductions in quality of life and psychiatric morbidity. Recent studies have suggested the efficacy of spinal cord stimulation (SCS) for the treatment of the back pain component in failed back surgery syndrome (FBSS) patients using a multicolumn lead. The main aim of this pilot study is to assess the influence and potential benefits of SCS on sleep quality in refractory FBSS patients implanted with multicolumn SCS and enrolled in the French multicentre ESTIMET study. METHODS: This is a single-centre, comparative, exploratory, pilot study. Sixteen FBSS patients enrolled in the ESTIMET study and implanted with multicolumn SCS will be monitored for 6months after implantation. Sleep parameters will be recorded by polysomnography, Psychomotor Vigilance Test and Osler tests, actigraphy, sleepiness scales, and sleep quality testing. Sleep will be evaluated before (at the inclusion visit) and after SCS implantation (at the 6-month visit). Secondary objectives will also assess the impact of SCS lead programming (mono vs. multicolumn SCS) and the influence of position-adaptive stimulation at night on sleep quality. TRIAL STATUS: The first patient of this ancillary study was enrolled on 21 May, 2012 and recruitment has now been achieved. Primary endpoint findings are expected to be available in 2015. CONCLUSION: By providing an analysis of the quality of sleep in chronic pain patients who are candidates for implanted neurostimulation, this new approach focuses on an important aspect of quality of life often overlooked in these poly-medication patients. It could show a real clinical benefit and underestimation of these analgesic innovative expensive techniques, where medico-economic analysis, would or would not promote access.

"MAST" prospective study: value of minimal access spine technologies technique for multicolumn spinal cord stimulation surgical lead implantation in the context of a French multicentre randomized controlled trial (ESTIMET study).

BACKGROUND AND PURPOSE: Spinal cord stimulation (SCS) has been demonstrated to be an effective treatment for postoperative persistent leg pain after spine surgery, but treatment of the back pain component remains much more difficult, as it comprises mixed neuropathic and mechanical pain mechanisms. Moreover, these patients could present damaged tissues at the site of SCS lead implantation as a result of previous spine surgery. It can therefore be logically assumed that minimizing the surgical invasiveness of SCS implantation would be beneficial for these patients. Several studies have demonstrated the value of Minimal Access Spine Technologies (MAST) in spine surgery, but only a few case reports have been published concerning the use of MAST techniques for SCS. Therefore, we were prompted to conduct a second ESTIMET ancillary study to prospectively analyse the potential impact and benefits of MAST technique during SCS lead implantation versus an open surgical approach. METHODS: This is a multicentre, comparative, ancillary study conducted in 61 patients among the 115 enrolled patients ESTIMET study. One arm comprises patients undergoing multicolumn lead implantation via a Conventional Open Approach (COA) and the other arm comprises patients implanted by a MAST approach. Patients will be followed for 12 months after lead implantation. The following data will be collected: elevation of muscle enzymes (serum CPK), scar size, blood loss, infection rate, operating time and global, leg, back and scar NPRS. TRIAL STATUS: The first patient of this ancillary study was enrolled on 21 May 2012 and recruitment has now been achieved. Primary endpoint findings are expected to be available in 2015. CONCLUSION: Minimally invasive techniques have now been used for spine surgery for the past 12 years, and could also be useful in the context of SCS lead implantation, especially in patients with chronic back pain prior to implantation.