The latest medical research on Dermatology

Autofluorescence (AF) - Raman spectroscopy is a technology that can detect residual basal cell carcinoma (BCC) on the resection margin of fresh surgically excised tissue specimens. The technology does not require tissue fixation, staining, labelling, or sectioning, and provides quantitative diagnosis maps of the surgical margins in 30 minutes.

To determine the accuracy of the AF-Raman instrument to detect incomplete excisions of BCC during Mohs micrographic surgery, using histology as reference standard.

Skin layers from 130 patients undergoing Mohs surgery at the Nottingham University Hospitals NHS Trust (September 2022 to July 2023) were investigated with the AF-Raman instrument. The layers were measured fresh, immediately after excision. The AF-Raman results and the intra-operative assessment by Mohs surgeons were compared to a post-operative consensus-derived reference produced by three dermatopathologists. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

The AF-Raman analysis was successfully completed for 125 out of the 130 layers. The AF-Raman analysis covered 91% of the specimen surface area on average, with the lowest being 87% for eyelid and the highest being 94% for forehead specimens. The AF-Raman instrument identified positive margins in 24 out of 36 BCC-positive cases, resulting in a 67% sensitivity (95% confidence intervals (CI): 49%-82%) and negative margins in 65 out of 89 BCC-negative cases, resulting in a 73% specificity (95% CI 63%-82%). Only one out of the 12 false negative cases was caused by misclassification by the AF-Raman algorithm. The other 11 false negatives cases were produced because no valid Raman signal was recorded at the location of the residual BCC due to either occlusion by blood or poor contact between tissue and cassette window. The intra-operative diagnosis by Mohs surgeons identified positive margins in 31 out of 36 BCC-positive cases, 86% sensitivity (95% CI: 70%-95%), and negative margins in 79 out of 89 BCC-negative cases, 89% specificity (95% CI: 81%-95%).

This study shows that the AF-Raman instrument has potential for intra-operative microscopic assessment of surgical margins in surgery of BCC. Further improvements are required for tissue processing to ensure complete coverage of the surgical specimens. ClinicalTrials.gov ID NCT03482622.

NCT04300296.

To evaluate the efficacy and safety of secukinumab 300 mg over 32 weeks in adult patients with biopsy-proven cutaneous LP (CLP), mucosal LP (MLP) or lichen planopilaris (LPP), inadequately controlled by topical corticosteroids.

PRELUDE was a, randomised, double-blind, placebo-controlled, Phase 2 proof-of-concept study that enrolled patients with CLP, MLP or LPP. Eligible patients were randomised to eithersecukinumab 300 mg every 4 weeks for 32 weeks (SECQ4W), or placebo for 16 weeks followed by secukinumab 300 mg every 2 weeks (SECQ2W) for 16 weeks. The primary endpoint was achievement of the newly designed Investigator's Global Assessment (IGA) score ≤2 at Week 16.

Overall, 111 patients were randomised (n=37 each) to CLP, MLP and LPP cohorts. As the proof-of-concept criteria were not met for any of the 3 cohorts, the primary objective was not met. A numerically higher proportion of patients achieved IGA ≤2 response at Week 16 with SECQ4W vs. placebo in the MLP (37.5% [95% credibility interval (Crl): 20.3-57.2] vs. 23.1% [95% Crl: 6.5-49.2]) and LPP cohorts (37.5% [95% Crl: 20.2-57.3] vs. 30.8% [95% Crl: 10.8-57.6]). In the LPP cohort, a sustained response for IGA ≤2 from Week 16 to Week 32 was achieved with SECQ4W (Week 16: 37.5%; Week 32: 45.8%), and a substantial improvement was observed in IGA ≤2 response in patients of this cohort switching from placebo (Week 16: 30.8%) to SECQ2W after Week 16 (Week 32: 63.6%). The safety profile was consistent with the known profile of secukinumab and showed no new or unexpected signals.

PRELUDE is the first randomised controlled basket trial evaluating interleukin-17A inhibition with secukinumab across 3 subtypes of LP. Secukinumab was well-tolerated and safe, showing different response rates across the 3 subtypes, with numerical IGA improvements in MLP and LPP, and no response in CLP. The study raises the question of a differential role of interleukin-17A across LP subtypes. The novel IGA score showed significant correlation with patient as well as physician reported outcome measurements.