Prospective Evaluation of Magnetic Resonance Imaging and [18F]Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography at Diagnosis and Before Maintenance Therapy in Symptomatic Patients With Multiple Myeloma Included in the IFM/DFCI 2009 Trial: Results of the IMAJEM Study

Purpose Magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) are important imaging techniques in multiple myeloma (MM). We conducted a prospective trial in patients with MM aimed at comparing MRI and PET-CT with respect to the detection of bone lesions at diagnosis and the prognostic value of the techniques. Patients and Methods One hundred thirty-four patients received a combination of lenalidomide, bortezomib, and dexamethasone (RVD) with or without autologous stem-cell transplantation, followed by lenalidomide maintenance. PET-CT and MRI were performed at diagnosis, after three cycles of RVD, and before maintenance therapy. The primary end point was the detection of bone lesions at diagnosis by MRI versus PET-CT. Secondary end points included the prognostic impact of MRI and PET-CT regarding progression-free (PFS) and overall survival (OS). Results At diagnosis, MRI results were positive in 127 of 134 patients (95%), and PET-CT results were positive in 122 of 134 patients (91%; P = .33). Normalization of MRI after three cycles of RVD and before maintenance was not predictive of PFS or OS. PET-CT became normal after three cycles of RVD in 32% of the patients with a positive evaluation at baseline, and PFS was improved in this group (30-month PFS, 78.7% v 56.8%, respectively). PET-CT normalization before maintenance was described in 62% of the patients who were positive at baseline. This was associated with better PFS and OS. Extramedullary disease at diagnosis was an independent prognostic factor for PFS and OS, whereas PET-CT normalization before maintenance was an independent prognostic factor for PFS. Conclusion There is no difference in the detection of bone lesions at diagnosis when comparing PET-CT and MRI. PET-CT is a powerful tool to evaluate the prognosis of de novo myeloma.

Inclusion of populations at risk of advanced melanoma in an opportunistic targeted screening project involving general practitioners

OBJECTIVE

The study objective was to measure the rates of inclusion of populations at risk of advanced melanoma in a pilot targeted screening project involving general practitioners.

DESIGN

This cross-sectional database study compared the inclusion rates of patients who signed inclusion in a targeted screening project with those of patients who did not, during a period in which both groups of patients consulted investigators.

SETTING

Data were extracted from the national healthcare insurance records in western France from 11 April to 30 October 2011.

PATIENTS

Patients, older than 18, considered for the data extraction had consulted one of the 78 participating GPs during the study period, and were affiliated with the national healthcare insurance.

MAIN OUTCOME MEASURES

Inclusion in the screening was the main outcome measure. Patients at risk of advanced melanoma were characterized by male gender, age over 50, low income, rural residence, farmer, and presence of chronic disease.

RESULTS

A total of 57,279 patients consulted GPs during the inclusion period and 2711 (4.73%) were included in the targeted screening. Populations at risk of advanced melanoma were less included: men (OR = 0.67; 95%CI [0.61-0.73]; p < 0.001), older than 50 (OR = 0.67; 95%CI [0.60-0.74]; p < 0.001), low income (OR = 0.65; 95%CI [0.55-0.77]; p < 0.001), farmer (OR = 0.23; 95%CI [0.17-0.30]; p < 0.001) and presence of a chronic disease (OR = 0.87; 95%CI [0.77-0.98]; p < 0.028).

CONCLUSION

This study demonstrated inequalities in the inclusion of patients in a melanoma screening. Patients at risk of advanced cancer were screened less often. Further studies should focus on GPs ability to identify and screen these patients. KEY POINTS Advanced melanoma is more frequently diagnosed in men, older patients and socioeconomically disadvantaged populations, which leads to survival inequalities. • Despite the involvement of general practitioners, the implementation of targeted melanoma screening did not avoid inclusion inequalities. • Men, older patients, patients suffering from chronic diseases, and low-income patients were less likely to benefit from screening. • The display of a conventional or an alarmist poster in the waiting room did not statistically reduce these inclusion inequalities.

Profile of vemurafenib-induced severe skin toxicities

BACKGROUND

Vemurafenib, a BRAF inhibitor, is commonly associated with skin toxicity. The impact of severe forms is unknown.

OBJECTIVE

To determine the rate of permanent vemurafenib discontinuation due to grade 3-4 skin toxicity, features of these toxicities, their recurrence rate after a switch to dabrafenib and their impact on overall survival.

METHODS

Retrospective cohort study of 131 patients treated with vemurafenib for melanoma between November 2010 and December 2014. Data on skin toxicities, the need for vemurafenib adjustment and the impact of switching to dabrafenib were collected. Regarding survival analysis, a conditional landmark analysis was performed to correct lead-time bias.

RESULTS

Among the 131 vemurafenib-treated patients, 26% developed grade 3-4 skin toxicity. Forty-four percent of them permanently discontinued their treatment, mainly due to rash and classic skin adverse reactions (Steven-Johnson syndrome, Drug Reaction with Eosinophilia and Systemic Symptoms). Conversely, photosensitivity and carcinomas rarely required treatment adjustment. Grade 3-4 rashes were associated with clinical or biological abnormalities in 94% of patients. Among the 10 patients who subsequently switched to dabrafenib, skin toxicity recurred only in one patient. Overall survival was significantly prolonged in case of severe skin toxicity emerging within the first 4 (P = 0.014) and 8 weeks (P = 0.038) on vemurafenib, with only a trend at 12 weeks (P = 0.052). Median overall survival was also prolonged in case of severe rash.

CONCLUSION

In this study, vemurafenib was continued in 56% of patients with grade 3-4 skin toxicity, which was associated with prolonged overall survival when emerging within the first 4 and 8 weeks of treatment. While developing severe skin adverse reactions permanently contraindicates vemurafenib use, other rashes should lead to retreatment attempts with dose reduction. In case of recurrence, dabrafenib seems to be an interesting option. For other skin toxicities, including photosensitivity and cutaneous carcinoma, treatment adjustment is usually not needed.

Development of brain metastases in patients with metastatic melanoma while receiving ipilimumab

Ipilimumab is a monoclonal antibody blocking the inhibitory molecule CTLA4 expressed by activated T lympocytes, used for the treatment of metastatic melanoma. Recent studies have shown its potential efficacy on brain metastases.

OBJECTIVES

To assess the development of brain metastases under ipilimumab and identify clinical, histological or evolving criteria related to the appearance of these metastases. A retrospective study was conducted in 52 patients treated with 4 cycles of ipilimumab 3 mg/kg every 3 weeks for unresectable stage III or stage IV melanoma between January 2011 and July 2013 in a Department of Dermato-Oncology. As no data has been find in the literature, the results were compared to our other cohort of patients treated with vemurafenib during the same period. Ten patients (21.7 %) developed brain metastases under ipilimumab in a median time of 6.58 months after treatment initiation. The multivariate analysis showed a lower rate of brain metastases in patients with acral lentiginous melanoma and melanoma of unknown primary site. The median survival after diagnosis of brain metastases was of 2.5 months. There was no significant difference with vemurafenib-treated patients in terms of incidence rate of brain metastasis, time of development and survival after diagnosis of cerebral metastases. This was the first study focused on the development of brain metastases under treatment with ipilimumab 3 mg/kg. Although ipilimumab is used for the treatment of brain metastases, it paradoxically did not seem to reduce the risk of developing brain metastases.

Proposal for an annual skin examination by a general practitioner for patients at high risk for melanoma: a French cohort study

OBJECTIVE

To evaluate the efficacy of a targeted screening for melanoma in high-risk patients following the receipt of a mailed invitation to an annual skin examination by a general practitioner (GP).

METHODS

A prospective cohort study was conducted in a primary care setting in western France. A total of 3897 patients at elevated risk of melanoma (identified using the Self-Assessment of Melanoma Risk Score) consented to participate in a targeted melanoma screening project in 2011. One year later, the participants were invited by mail to consult their GP for an annual skin examination. Efficacy of the procedure was evaluated according to patient participation and the number of melanomas detected. The consultation dates and results were collected during the 12 months postreminder and were analysed using SAS. Analyses of whether participation decreased compared with that during the year of inclusion and whether populations at risk for thick melanoma showed reduced participation in the screening were performed.

RESULTS

Of the 3745 patients who received the mailed invitation, 61% underwent a skin examination. The participation of patients at risk for thick melanoma (any patient over 60 years of age and men over 50 years of age) was significantly greater than that of the patients in the other subgroups (72.4% vs 49.6%, p<0.001; and 66% vs 52.4%, p<0.001, respectively). The patients referred to the dermatologist after 1 year were more compliant compared with those referred during the first year (68.8% vs 59.1%, p=0.003). Six melanomas were detected within 1 year postreminder; therefore, the incidence of melanoma in the study population was 160/100 000.

CONCLUSIONS

This study confirms the benefits of developing a targeted screening strategy in primary care. In particular, after the annual reminder, patient participation and the diagnosis of melanoma remained high in the patients at elevated risk of thick melanomas.

TRIAL REGISTRATION NUMBER

NCT01610531.

Adoptive T cell therapy combined with intralesional administrations of TG1042 (adenovirus expressing interferon-γ) in metastatic melanoma patients

Tumor immune escape has recently been shown to be related to the development of an immune tolerance state of the microenvironment. Cytokines activating the immune system such as IFN-γ can be used to reverse the immune escape and thus to potentiate the efficacy of immunotherapy. A clinical study was conducted in 18 stage IIIc/IV melanoma patients treated with tumor-infiltrating lymphocytes (TILs) in combination with intratumoral TG1042 injection (adenovirus expressing IFN-γ). The primary objective was to investigate the safety of treatment. Secondary objectives were to study the clinical response and translational research. The treatment was well tolerated. Among the 13 patients evaluable for tumor response, 38.5% had an overall objective response (OOR = CR + PR) and disease control rate (DCR = CR + PR + S) of 46%. The clinical response of the 37 targeted lesions led to an OOR of 51% and a DCR of 75%. Translational research on predictive markers did not significantly differ between responder and non-responder patients. However, specifically regarding injected lesions, the clinical response correlated with CD3-/CD56+ NK cells which could be activated by TG1042. Further larger studies of this combined immunotherapy are needed to confirm our findings. Intralesional TG1042 combined with antigen-selected TILs should be discussed.

[The role of the expansion cohort in phase I trials in oncology: guidelines of the phase I HUB]

At the end of the dose escalation step of phase I trials in oncology, it is increasingly frequent to include patients in expansion cohorts. However, the objective of the expansion cohorts, the number of patients included and their justification are insufficiently explained in the protocols. These cohorts are sometimes of considerable size. The aim of this article is to outline the methodology of expansion cohorts in order to provide recommendations for their planning in practice. This work has been undertaken in collaboration with the statisticians of the early phase investigation centers (CLIP(2)), supported by INCA. First, we have outlined the recent articles published on the expansion cohorts in phase I. We then proposed recommendations, in terms of objectives and number of patients to be included, to guide investigators and facilitate the use of these expansion cohorts in practice. Manji et al. have identified 149 phase I clinical trials using expansion cohorts in oncology with a review of the literature between 2006 and 2011 (Manji et al., 2013). Objectives of the expansion cohort were reported in 111 trials (74%). In these trials, safety was the most reported objective (80% of trials), followed by efficacy (45%). According to this review, the number of patients included in these cohorts was insufficiently justified. This result was confirmed by the study of literature that we conducted over the period 2011-2014. We propose to define the number of patients to be included in expansion cohorts in terms of (1) their objectives, (2) the statistical criteria and (3) the clinical context of the trial. The toxicity study remains the primary objective to evaluate in the expansion phase. In some contexts, the activity study is considered as co-primary objective, either for identifying preliminary signs of activity in studies like screening, or for studying the activity when the target population is known. This study is then considered as phase I/II, and experience plans of phase II can be adapted for planning expansion cohorts. Recommendations for the size of expansion cohorts are proposed. Despite the exploratory character of the expansion cohort, a justification of their size based on assumptions statistically defined is recommended in order to provide an interpretable conclusion and to quantify the risk of errors.

0.5% levobupivacaine versus 0.5% ropivacaine: Are they different in ultrasound-guided sciatic block?

Context and Aims:

Little is known about onset and duration of sciatic block after 0.5% levobupivacaine (Levo) versus 0.5% ropivacaine (Ropi) for ultrasound-guided technique. We assessed these parameters in the ultrasound-guided block, to know for the practice.

Setting and Design:

A comparative randomized double-blind study was conducted in the University Hospital.

Materials and Methods:

Were included 35 adults of ASA I-II, scheduled for foot surgery, presenting clear imaging of their sciatic nerve at mid-thigh. A volume of 20 mL of either 0.5% Levo or 0.5% Ropi were injected around the sciatic nerve at mid-thigh using ultrasound guidance (out of the plane) followed by placement of a catheter to use, if necessary, for perioperative analgesia. A femoral single shot block was systematically performed to block the saphenous nerve. The onset times until complete foot block (primary outcome) and the sensory and motor block duration (secondary outcome) were assessed using Wilcoxon test. Values were expressed as medians (1^st-3^rd quartile).

Results:

Except for two delayed sciatic blocks in each group, the onset time otherwise was 35 min (20-60) in Ropi versus 40 min (30-60) in Levo, P = 0.5. Sensory block lasted longer in Levo, 17 h (14-27) compared with 15 h (10-17) in Ropi, P = 0.04. No significant between-group difference was found with motor block durations, 15 h (12-18) in Levo and 15 h (12-16) in Ropi, P = 0.3.

Conclusion:

No difference of onset times was found in ultrasound-guided sciatic block whether using Levo or Ropi. Levo induced a longer-lasting sensory block.

Younger age at the time of first metastasis in BRAF-mutated compared to BRAF wild-type melanoma patients

The relationship between BRAF mutations and the patient clinical profile is still under question. The objective of the present study was to correlate the BRAF mutation status in primary and metastatic melanomas with the clinicopathological profile, disease-free (DFS) and overall survival (OS). A total of 367 melanoma samples from 278 patients were screened for their BRAF status using a combination of allele-specific amplification and DNA sequencing. Two or three tissue samples from the same patient were available for 74 patients. The clinicopathological characteristics were tested for their association with the BRAF mutation using the Fisher's or Pearson's χ2 test. Log-rank tests and Cox models were used for survival analyses. BRAF mutation was found in 152 samples (41.4%). Ten of the 74 patients with several tissue samples (13.5%) had discordant BRAF mutation results. BRAF-mutated patients were significantly younger at the time of primary melanoma and first diagnosis of metastasis than BRAF wild-type patients but with no difference in DFS and OS. According to our results, a primary melanoma with BRAF mutation is not associated with a more aggressive illness.

Targeted melanoma prevention intervention: a cluster randomized controlled trial

PURPOSE

Targeted interventions to reduce the risk and increase the early detection of melanoma have the potential to save lives. We aimed to assess the effect of such an intervention on patient prevention behavior.

METHODS

We conducted a pilot clustered randomized controlled trial, comparing a targeted screening and education intervention with a conventional information-based campaign in 20 private surgeries in western France. In the intervention group, 10 general practitioners identified patients at elevated risk for melanoma with a validated assessment tool, the Self-Assessment Melanoma Risk Score (SAMScore), examined their skin, and counseled them using information leaflets. In the control group, 10 general practitioners displayed a poster and the leaflets in their waiting room and examined patients' skin at their own discretion. The main outcome measures were sunbathing and skin self-examinations among patients at elevated risk, assessed 5 months later with a questionnaire.

RESULTS

Analyses were based on 173 patients. Compared with control patients, intervention patients were more likely to remember the campaign (81.4% vs 50.0%, P = .0001) and to correctly identify their elevated risk of melanoma (71.1% vs 42.1%, P = .001). Furthermore, intervention patients had higher levels of prevention behaviors: they were less likely to sunbathe in the summer (24.7% vs 40.8%, P = .048) and more likely to have performed skin self-examinations in the past year (52.6% vs 36.8%, P = .029). The intervention was not associated with any clear adverse effects, although there were trends whereby intervention patients were more likely to worry about melanoma and to consult their general practitioner again about the disease.

CONCLUSIONS

The combination of use of the SAMScore and general practitioner examination and counseling during consultations is an efficient way to promote patient behaviors that may reduce melanoma risk. Extending the duration of follow-up and demonstrating an impact on morbidity and mortality remain major issues for further research.

A recall program for the outcome of conventional root canal treatment performed in a teaching hospital

OBJECTIVES

This study investigated the long-term survival and the prognostic factors of endodontic treatments performed in a dental teaching hospital. The aim was to calculate the probabilities of success or failure according to the follow-up extent and to assess the time allowed for a complete periapical healing.

MATERIALS AND METHODS

A cohort of 185 teeth were re-examined 1-4 years after treatment. The outcome was assessed on the basis of radiographic and clinical criteria as success, uncertain or failure. A survival analysis using the Cox model was used (i) to explore tooth survival and periapical healing over the time and (ii) to highlight the predictive factors of treatment outcome.

RESULTS

After 2 years, the appearance of an apical periodontitis remained lower than 3.5%, whereas only 22.8% of periapical healed cases were notified. The prognosis factors are: (i) for teeth with initial healthy periapical conditions, coronal leakage (p = 0.002) with the higher risk of failure (RR = 19.77), absence of correspondence filling length/shaping = 0.026), type of teeth (p = 0.041) and (ii) for teeth with apical periodontitis, number of root canals (p = 0.000,91), correspondence filling length/shaping length (p = 0.017) and over-filling (p = 0.09). New periapical lesions or tooth loss were recorded after 2 years. Half of the successful cases of periapical healing were observed during the follow-up from 2-4 years.

CONCLUSIONS

This longitudinal study shows that coronal leakage is responsible for late failure and that periapical healing is long to achieve. Therefore, endodontic treatments may require a follow-up of over 2 years.

Non-homogeneous effect of levodopa on inhibitory circuits in Parkinson's disease and dyskinesia

INTRODUCTION

Levodopa-induced dyskinesia in patients with Parkinson's disease (PD) has been shown to be associated with an abnormal plasticity in the motor cortex. We investigated whether changes in the excitability of inhibitory and excitatory motor circuits could underlie maladaptive mechanisms associated with dyskinesia.

METHODS

Using single and paired transcranial magnetic stimulation (TMS), we studied motor threshold, silent period (SP) duration, intracortical facilitation (ICF), short intracortical inhibition (SICI) and low- and high-intensity long intracortical inhibition (LICI) in 10 dyskinetic and 10 non-dyskinetic patients, matched for disease and treatment duration, before (OFF state) and after (ON state) levodopa, and in 10 healthy controls.

RESULTS

In the OFF state, the two groups of patients showed similar motor cortex excitability with a reduced SICI compared to controls. LICI was weaker and increasing stimulation intensity had a lower effect on SP duration in dyskinetic patients than in controls. In dyskinetic patients, in contrast to non-dyskinetic patients, levodopa failed to increase SICI and SP duration, and potentiated to a lesser extent the effect of increasing the stimulation intensity on LICI. Although levodopa improved motor symptoms to a similar extent in both dyskinetic and non-dyskinetic patients, it failed to activate effectively the excitability of the inhibitory systems in dyskinetic patients.

DISCUSSION

These findings suggest that dyskinesia is associated with an abnormal effect of levodopa on cortical motor inhibitory circuits.

Topical corticosteroid phobia in atopic dermatitis: a study of its nature, origins and frequency

BACKGROUND

Topical corticosteroids remain the mainstay of atopic dermatitis therapy. Many atopic dermatitis therapeutic failures appear to be attributable to poor adherence to treatment due to topical corticosteroid phobia.

OBJECTIVES

To assess the facets, origins and frequency of fear of topical corticosteroid use among patients with atopic dermatitis.

METHODS

A questionnaire comprising 69 items, generated from information gathered during interviews with 21 patients and 15 health professionals, was given to consecutive patients consulting at the outpatient dermatology departments of five regional university hospitals or with 53 dermatologists in private practice.

RESULTS

A total of 208 questionnaires were analysed (including 144 from parents and 87 from adult patients, 27 of whom were also parents); 80·7% of the respondents reported having fears about topical corticosteroids and 36% admitted nonadherence to treatment. A correlation was found between topical corticosteroid phobia and the need for reassurance, the belief that topical corticosteroids pass through the skin into the bloodstream, a prior adverse event, inconsistent information about the quantity of cream to apply, a desire to self-treat for the shortest time possible or poor treatment adherence. Topical corticosteroid phobia was not correlated with atopic dermatitis severity.

CONCLUSION

Topical corticosteroid phobia is a genuine and complex phenomenon, common among French patients with atopic dermatitis, that has an important impact on treatment compliance.

Is primary melanoma ulceration a factor of good response to adoptive immunotherapy?

BACKGROUND

Primary melanoma ulceration is a factor of poor prognosis at the local and regional stage. The physiopathological mechanisms which explain its prognostic impact are still little known. However, two recent studies suggest that it could be a predictive factor of good response to a non-specific immunotherapy (interferon-alpha) and to an active immunotherapy (vaccine).

OBJECTIVE

The aim of this study was to determine whether ulceration could be a factor of good prognosis in the context of an adoptive immunotherapy with tumour infiltrating lymphocytes (TIL) in stage III regional lymph node metastatic melanoma (sixth American Joint Committee on Cancer staging system) and whether it was associated with an improvement in the effectiveness of this treatment compared with the control group.

METHODS

We have included all the patients treated in open prospective randomized TIL vs. control protocols in our unit from 1997 to 2009. Clinical data were derived retrospectively from patient files. Statistical analysis was performed using log-rank tests, Cox models and tests for interaction.

RESULTS

A total of 144 patients were included. In the group of 80 patients treated with TIL, primary melanoma ulceration remained a pejorative factor for relapse-free and overall survival in univariate and multivariate analysis. The presence of ulceration did not change the effectiveness of TIL treatment in comparison with the control group with regards to relapse-free and overall survival.

CONCLUSION

Our study demonstrates that primary melanoma ulceration does not have any impact on the response to TIL adoptive immunotherapy and thus does not confirm its positive prognostic value suggested by two other immunotherapy approaches.

Absence of modulation of CD4+CD25 regulatory T cells in CTCL patients treated with bexarotene

Cutaneous T-cell lymphoma (CTCL) are a heterogeneous group of lymphoproliferative disorders, characterized by the infiltration of the epidermis by mature and activated malignant CD4+ T-lymphocytes. Retinoids such as retinoic acid and synthetic analogues have long been used alone or in combination with other therapies for CTCL. Bexarotene, the first synthetic highly selective RXR retinoid, was approved for the treatment of all stages of CTCL in patients refractory to at least one systemic therapy. Recently, six cases in which the initiation of bexarotene therapy for CTCL was associated with the progression of internal disease despite improvement of cutaneous signs and symptoms were reported. Moreover, it has been established that retinoids promote the generation of CD4+ Foxp3+ regulatory T cells, raising the question of an induction of regulatory T-cells by bexarotene. The aim of this work was to determine if bexarotene induces an increase of functional regulatory T cells which could play a role in the development of secondary extra-cutaneous lymphomas. Regulatory T cells were studied both in cutaneous biopsy specimens using an immunohistochemical analysis of CD4, CD25 and Foxp3 and in blood where proportion and functionality of circulating CD4+CD25(high) T-cells were determined. The study was performed in 10 patients [five patients with Sézary syndrome (SS) and five mycosis fungoïdes (MF)], treated for 6 months with bexarotene. Four healthy donors were used as controls for phenotypic and functional analysis on PBL. We found that the frequency of CD4+CD25(high) Treg cells was not significantly different before starting bexarotene and after 6 months of treatment in CTCL patients. However, we observed that the frequency of CD4+CD25(high) Treg cells before the beginning of the treatment was significantly increased compared to healthy donors. In addition, functional assays demonstrated that Foxp3 expressing CD4+CD25(high) T-cells were capable of suppressing autologous CD4 + CD25- T-cell proliferation. In the present work, we detected the presence of functional circulating CD4+CD25(high) Foxp3+ regulatory T-cells in CTCL patients, with an increased frequency compared to healthy donors. The treatment with bexarotene does not seem to affect the regulatory T-cell compartment.

About the cutaneous targets of bexarotene in CTCL patients

There are several approved therapies for cutaneous T-cell lymphoma (CTCL). The retinoids are one of the major biologic response modifiers used in CTCL, producing good response rates but few complete responses. Bexarotene has been demonstrated to act on malignant T-cells by inducing their apoptosis, but nothing is known about its role on keratinocytes and Langerhans cells. Immunohistochemical analysis using CD1a, HLA-DR, ICAM-1 (activation markers), CD95 and CD40 (apoptosis markers) was conducted on frozen sections of bexarotene-exposed cutaneous explants and skin biopsy specimens from patients treated with bexarotene. None of the studied markers was significantly modulated both on cutaneous explants and on skin biopsy specimens after treatment with bexarotene, compared to controls. Langerhans cells and keratinocytes do not appear to play a central role in the therapeutic control of CTCL by bexarotene therapy. The main bexarotene's target thus remains T-cells by inducing their apoptosis, a mechanism that is different from the other retinoids used in CTCL.

Effects of lumbar artificial disc design on intervertebral mobility: in vivo comparison between mobile-core and fixed-core

Although in theory, the differences in design between fixed-core and mobile-core prostheses should influence motion restoration, in vivo kinematic differences linked with prosthesis design remained unclear. The aim of this study was to investigate the rationale that the mobile-core design seems more likely to restore physiological motion since the translation of the core could help to mimic the kinematic effects of the natural nucleus. In vivo intervertebral motion characteristics of levels implanted with the mobile-core prosthesis were compared with untreated levels of the same population, levels treated by a fixed-core prosthesis, and normal levels (data from literature). Patients had a single-level implantation at L4L5 or L5S1 including 72 levels with a mobile-core prosthesis and 33 levels with a fixed-core prosthesis. Intervertebral mobility characteristics included the range of motion (ROM), the motion distribution between flexion and extension, the prosthesis core translation (CT), and the intervertebral translation (VT). A method adapted to the implanted segments was developed to measure the VT: metal landmarks were used instead of the bony landmarks. The reliability assessment of the VT measurement method showed no difference between three observers (p < 0.001), a high level of agreement (ICC = 0.908) and an interobserver precision of 0.2 mm. Based on this accurate method, this in vivo study demonstrated that the mobile-core prosthesis replicated physiological VT at L4L5 levels but not at L5S1 levels, and that the fixed-core prosthesis did not replicate physiological VT at any level by increasing VT. As the VT decreased when the CT increased (p < 0.001) it was proven that the core mobility minimized the VT. Furthermore, some physiologic mechanical behaviors seemed to be maintained: the VT was higher at implanted the L4L5 level than at the implanted L5S1 level, and the CT appeared lower at the L4L5 level than at the L5S1 level. ROM and motion distribution were not different between the mobile-core prosthesis and the fixed-core prosthesis implanted levels. This study validated in vivo the concept that a mobile-core helps to restore some physiological mechanical characteristics of the VT at the implanted L4L5 level, but also showed that the minimizing effect of core mobility on the VT was not sufficient at the L5S1 level.